Add lua 5.4.0 test suite

118 files changed, 59816 insertions, 0 deletions

diff --git a/test/external/lua-5.4.0-tests/all.lua b/test/external/lua-5.4.0-tests/all.lua
new file mode 100644
index 0000000..db074dd
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/all.lua
@@ -0,0 +1,321 @@
+#!../lua
+-- $Id: testes/all.lua $
+-- See Copyright Notice at the end of this file
+
+
+local version = "Lua 5.4"
+if _VERSION ~= version then
+  io.stderr:write("This test suite is for ", version,
+                  ", not for ", _VERSION, "\nExiting tests")
+  return
+end
+
+
+_G.ARG = arg   -- save arg for other tests
+
+
+-- next variables control the execution of some tests
+-- true means no test (so an undefined variable does not skip a test)
+-- defaults are for Linux; test everything.
+-- Make true to avoid long or memory consuming tests
+_soft = rawget(_G, "_soft") or false
+-- Make true to avoid non-portable tests
+_port = rawget(_G, "_port") or false
+-- Make true to avoid messages about tests not performed
+_nomsg = rawget(_G, "_nomsg") or false
+
+
+local usertests = rawget(_G, "_U")
+
+if usertests then
+  -- tests for sissies ;)  Avoid problems
+  _soft = true
+  _port = true
+  _nomsg = true
+end
+
+-- tests should require debug when needed
+debug = nil
+
+
+if usertests then
+  T = nil    -- no "internal" tests for user tests
+else
+  T = rawget(_G, "T")  -- avoid problems with 'strict' module
+end
+
+
+--[=[
+  example of a long [comment],
+  [[spanning several [lines]]]
+
+]=]
+
+print("\n\tStarting Tests")
+
+do
+  -- set random seed
+  local random_x, random_y = math.randomseed()
+  print(string.format("random seeds: %d, %d", random_x, random_y))
+end
+
+print("current path:\n****" .. package.path .. "****\n")
+
+
+local initclock = os.clock()
+local lastclock = initclock
+local walltime = os.time()
+
+local collectgarbage = collectgarbage
+
+do   -- (
+
+-- track messages for tests not performed
+local msgs = {}
+function Message (m)
+  if not _nomsg then
+    print(m)
+    msgs[#msgs+1] = string.sub(m, 3, -3)
+  end
+end
+
+assert(os.setlocale"C")
+
+local T,print,format,write,assert,type,unpack,floor =
+      T,print,string.format,io.write,assert,type,table.unpack,math.floor
+
+-- use K for 1000 and M for 1000000 (not 2^10 -- 2^20)
+local function F (m)
+  local function round (m)
+    m = m + 0.04999
+    return format("%.1f", m)      -- keep one decimal digit
+  end
+  if m < 1000 then return m
+  else
+    m = m / 1000
+    if m < 1000 then return round(m).."K"
+    else
+      return round(m/1000).."M"
+    end
+  end
+end
+
+local Cstacklevel
+
+local showmem
+if not T then
+  local max = 0
+  showmem = function ()
+    local m = collectgarbage("count") * 1024
+    max = (m > max) and m or max
+    print(format("    ---- total memory: %s, max memory: %s ----\n",
+          F(m), F(max)))
+  end
+  Cstacklevel = function () return 0 end   -- no info about stack level
+else
+  showmem = function ()
+    T.checkmemory()
+    local total, numblocks, maxmem = T.totalmem()
+    local count = collectgarbage("count")
+    print(format(
+      "\n    ---- total memory: %s (%.0fK), max use: %s,  blocks: %d\n",
+      F(total), count, F(maxmem), numblocks))
+    print(format("\t(strings:  %d, tables: %d, functions: %d, "..
+                 "\n\tudata: %d, threads: %d)",
+                 T.totalmem"string", T.totalmem"table", T.totalmem"function",
+                 T.totalmem"userdata", T.totalmem"thread"))
+  end
+
+  Cstacklevel = function ()
+    local _, _, ncalls, nci = T.stacklevel()
+    return ncalls  + nci   -- number of free slots in the C stack
+  end
+end
+
+
+local Cstack = Cstacklevel()
+
+--
+-- redefine dofile to run files through dump/undump
+--
+local function report (n) print("\n***** FILE '"..n.."'*****") end
+local olddofile = dofile
+local dofile = function (n, strip)
+  showmem()
+  local c = os.clock()
+  print(string.format("time: %g (+%g)", c - initclock, c - lastclock))
+  lastclock = c
+  report(n)
+  local f = assert(loadfile(n))
+  local b = string.dump(f, strip)
+  f = assert(load(b))
+  return f()
+end
+
+dofile('main.lua')
+
+do
+  local next, setmetatable, stderr = next, setmetatable, io.stderr
+  -- track collections
+  local mt = {}
+  -- each time a table is collected, remark it for finalization
+  -- on next cycle
+  mt.__gc = function (o)
+     stderr:write'.'    -- mark progress
+     local n = setmetatable(o, mt)   -- remark it
+   end
+   local n = setmetatable({}, mt)    -- create object
+end
+
+report"gc.lua"
+local f = assert(loadfile('gc.lua'))
+f()
+
+dofile('db.lua')
+assert(dofile('calls.lua') == deep and deep)
+olddofile('strings.lua')
+olddofile('literals.lua')
+dofile('tpack.lua')
+assert(dofile('attrib.lua') == 27)
+dofile('gengc.lua')
+assert(dofile('locals.lua') == 5)
+dofile('constructs.lua')
+dofile('code.lua', true)
+if not _G._soft then
+  report('big.lua')
+  local f = coroutine.wrap(assert(loadfile('big.lua')))
+  assert(f() == 'b')
+  assert(f() == 'a')
+end
+dofile('cstack.lua')
+dofile('nextvar.lua')
+dofile('pm.lua')
+dofile('utf8.lua')
+dofile('api.lua')
+assert(dofile('events.lua') == 12)
+dofile('vararg.lua')
+dofile('closure.lua')
+dofile('coroutine.lua')
+dofile('goto.lua', true)
+dofile('errors.lua')
+dofile('math.lua')
+dofile('sort.lua', true)
+dofile('bitwise.lua')
+assert(dofile('verybig.lua', true) == 10); collectgarbage()
+dofile('files.lua')
+
+if #msgs > 0 then
+  local m = table.concat(msgs, "\n  ")
+  warn("#tests not performed:\n  ", m, "\n")
+end
+
+print("(there should be two warnings now)")
+warn("@on")
+warn("#This is ", "an expected", " warning")
+warn("@off")
+warn("******** THIS WARNING SHOULD NOT APPEAR **********")
+warn("******** THIS WARNING ALSO SHOULD NOT APPEAR **********")
+warn("@on")
+warn("#This is", " another one")
+
+-- no test module should define 'debug'
+assert(debug == nil)
+
+local debug = require "debug"
+
+print(string.format("%d-bit integers, %d-bit floats",
+        string.packsize("j") * 8, string.packsize("n") * 8))
+
+debug.sethook(function (a) assert(type(a) == 'string') end, "cr")
+
+-- to survive outside block
+_G.showmem = showmem
+
+
+assert(Cstack == Cstacklevel(),
+  "should be at the same C-stack level it was when started the tests")
+
+end   --)
+
+local _G, showmem, print, format, clock, time, difftime,
+      assert, open, warn =
+      _G, showmem, print, string.format, os.clock, os.time, os.difftime,
+      assert, io.open, warn
+
+-- file with time of last performed test
+local fname = T and "time-debug.txt" or "time.txt"
+local lasttime
+
+if not usertests then
+  -- open file with time of last performed test
+  local f = io.open(fname)
+  if f then
+    lasttime = assert(tonumber(f:read'a'))
+    f:close();
+  else   -- no such file; assume it is recording time for first time
+    lasttime = nil
+  end
+end
+
+-- erase (almost) all globals
+print('cleaning all!!!!')
+for n in pairs(_G) do
+  if not ({___Glob = 1, tostring = 1})[n] then
+    _G[n] = undef
+  end
+end
+
+
+collectgarbage()
+collectgarbage()
+collectgarbage()
+collectgarbage()
+collectgarbage()
+collectgarbage();showmem()
+
+local clocktime = clock() - initclock
+walltime = difftime(time(), walltime)
+
+print(format("\n\ntotal time: %.2fs (wall time: %gs)\n", clocktime, walltime))
+
+if not usertests then
+  lasttime = lasttime or clocktime    -- if no last time, ignore difference
+  -- check whether current test time differs more than 5% from last time
+  local diff = (clocktime - lasttime) / lasttime
+  local tolerance = 0.05    -- 5%
+  if (diff >= tolerance or diff <= -tolerance) then
+    warn(format("#time difference from previous test: %+.1f%%",
+                  diff * 100))
+  end
+  assert(open(fname, "w")):write(clocktime):close()
+end
+
+print("final OK !!!")
+
+
+
+--[[
+*****************************************************************************
+* Copyright (C) 1994-2016 Lua.org, PUC-Rio.
+*
+* Permission is hereby granted, free of charge, to any person obtaining
+* a copy of this software and associated documentation files (the
+* "Software"), to deal in the Software without restriction, including
+* without limitation the rights to use, copy, modify, merge, publish,
+* distribute, sublicense, and/or sell copies of the Software, and to
+* permit persons to whom the Software is furnished to do so, subject to
+* the following conditions:
+*
+* The above copyright notice and this permission notice shall be
+* included in all copies or substantial portions of the Software.
+*
+* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+*****************************************************************************
+]]
+
diff --git a/test/external/lua-5.4.0-tests/api.lua b/test/external/lua-5.4.0-tests/api.lua
new file mode 100644
index 0000000..9447e42
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/api.lua
@@ -0,0 +1,1462 @@
+-- $Id: testes/api.lua $
+-- See Copyright Notice in file all.lua
+
+if T==nil then
+  (Message or print)('\n >>> testC not active: skipping API tests <<<\n')
+  return
+end
+
+local debug = require "debug"
+
+local pack = table.pack
+
+
+function tcheck (t1, t2)
+  assert(t1.n == (t2.n or #t2) + 1)
+  for i = 2, t1.n do assert(t1[i] == t2[i - 1]) end
+end
+
+
+local function checkerr (msg, f, ...)
+  local stat, err = pcall(f, ...)
+  assert(not stat and string.find(err, msg))
+end
+
+
+print('testing C API')
+
+a = T.testC("pushvalue R; return 1")
+assert(a == debug.getregistry())
+
+
+-- absindex
+assert(T.testC("settop 10; absindex -1; return 1") == 10)
+assert(T.testC("settop 5; absindex -5; return 1") == 1)
+assert(T.testC("settop 10; absindex 1; return 1") == 1)
+assert(T.testC("settop 10; absindex R; return 1") < -10)
+
+-- testing alignment
+a = T.d2s(12458954321123.0)
+assert(a == string.pack("d", 12458954321123.0))
+assert(T.s2d(a) == 12458954321123.0)
+
+a,b,c = T.testC("pushnum 1; pushnum 2; pushnum 3; return 2")
+assert(a == 2 and b == 3 and not c)
+
+f = T.makeCfunc("pushnum 1; pushnum 2; pushnum 3; return 2")
+a,b,c = f()
+assert(a == 2 and b == 3 and not c)
+
+-- test that all trues are equal
+a,b,c = T.testC("pushbool 1; pushbool 2; pushbool 0; return 3")
+assert(a == b and a == true and c == false)
+a,b,c = T.testC"pushbool 0; pushbool 10; pushnil;\
+                      tobool -3; tobool -3; tobool -3; return 3"
+assert(a==false and b==true and c==false)
+
+
+a,b,c = T.testC("gettop; return 2", 10, 20, 30, 40)
+assert(a == 40 and b == 5 and not c)
+
+t = pack(T.testC("settop 5; return *", 2, 3))
+tcheck(t, {n=4,2,3})
+
+t = pack(T.testC("settop 0; settop 15; return 10", 3, 1, 23))
+assert(t.n == 10 and t[1] == nil and t[10] == nil)
+
+t = pack(T.testC("remove -2; return *", 2, 3, 4))
+tcheck(t, {n=2,2,4})
+
+t = pack(T.testC("insert -1; return *", 2, 3))
+tcheck(t, {n=2,2,3})
+
+t = pack(T.testC("insert 3; return *", 2, 3, 4, 5))
+tcheck(t, {n=4,2,5,3,4})
+
+t = pack(T.testC("replace 2; return *", 2, 3, 4, 5))
+tcheck(t, {n=3,5,3,4})
+
+t = pack(T.testC("replace -2; return *", 2, 3, 4, 5))
+tcheck(t, {n=3,2,3,5})
+
+t = pack(T.testC("remove 3; return *", 2, 3, 4, 5))
+tcheck(t, {n=3,2,4,5})
+
+t = pack(T.testC("copy 3 4; return *", 2, 3, 4, 5))
+tcheck(t, {n=4,2,3,3,5})
+
+t = pack(T.testC("copy -3 -1; return *", 2, 3, 4, 5))
+tcheck(t, {n=4,2,3,4,3})
+
+do   -- testing 'rotate'
+  local t = {10, 20, 30, 40, 50, 60}
+  for i = -6, 6 do
+    local s = string.format("rotate 2 %d; return 7", i)
+    local t1 = pack(T.testC(s, 10, 20, 30, 40, 50, 60))
+    tcheck(t1, t)
+    table.insert(t, 1, table.remove(t))
+  end
+
+  t = pack(T.testC("rotate -2 1; return *", 10, 20, 30, 40))
+  tcheck(t, {10, 20, 40, 30})
+  t = pack(T.testC("rotate -2 -1; return *", 10, 20, 30, 40))
+  tcheck(t, {10, 20, 40, 30})
+
+  -- some corner cases
+  t = pack(T.testC("rotate -1 0; return *", 10, 20, 30, 40))
+  tcheck(t, {10, 20, 30, 40})
+  t = pack(T.testC("rotate -1 1; return *", 10, 20, 30, 40))
+  tcheck(t, {10, 20, 30, 40})
+  t = pack(T.testC("rotate 5 -1; return *", 10, 20, 30, 40))
+  tcheck(t, {10, 20, 30, 40})
+end
+
+
+-- testing warnings
+T.testC([[
+  warningC "#This shold be a"
+  warningC " single "
+  warning "warning"
+  warningC "#This should be "
+  warning "another one"
+]])
+
+
+-- testing message handlers
+do
+  local f = T.makeCfunc[[
+    getglobal error
+    pushstring bola
+    pcall 1 1 1   # call 'error' with given handler
+    pushstatus
+    return 2     # return error message and status
+  ]]
+
+  local msg, st = f(string.upper)   -- function handler
+  assert(st == "ERRRUN" and msg == "BOLA")
+  local msg, st = f(string.len)     -- function handler
+  assert(st == "ERRRUN" and msg == 4)
+
+end
+
+t = pack(T.testC("insert 3; pushvalue 3; remove 3; pushvalue 2; remove 2; \
+                  insert 2; pushvalue 1; remove 1; insert 1; \
+      insert -2; pushvalue -2; remove -3; return *",
+      2, 3, 4, 5, 10, 40, 90))
+tcheck(t, {n=7,2,3,4,5,10,40,90})
+
+t = pack(T.testC("concat 5; return *", "alo", 2, 3, "joao", 12))
+tcheck(t, {n=1,"alo23joao12"})
+
+-- testing MULTRET
+t = pack(T.testC("call 2,-1; return *",
+     function (a,b) return 1,2,3,4,a,b end, "alo", "joao"))
+tcheck(t, {n=6,1,2,3,4,"alo", "joao"})
+
+do  -- test returning more results than fit in the caller stack
+  local a = {}
+  for i=1,1000 do a[i] = true end; a[999] = 10
+  local b = T.testC([[pcall 1 -1 0; pop 1; tostring -1; return 1]],
+                    table.unpack, a)
+  assert(b == "10")
+end
+
+
+-- testing globals
+_G.a = 14; _G.b = "a31"
+local a = {T.testC[[
+  getglobal a;
+  getglobal b;
+  getglobal b;
+  setglobal a;
+  return *
+]]}
+assert(a[2] == 14 and a[3] == "a31" and a[4] == nil and _G.a == "a31")
+
+
+-- testing arith
+assert(T.testC("pushnum 10; pushnum 20; arith /; return 1") == 0.5)
+assert(T.testC("pushnum 10; pushnum 20; arith -; return 1") == -10)
+assert(T.testC("pushnum 10; pushnum -20; arith *; return 1") == -200)
+assert(T.testC("pushnum 10; pushnum 3; arith ^; return 1") == 1000)
+assert(T.testC("pushnum 10; pushstring 20; arith /; return 1") == 0.5)
+assert(T.testC("pushstring 10; pushnum 20; arith -; return 1") == -10)
+assert(T.testC("pushstring 10; pushstring -20; arith *; return 1") == -200)
+assert(T.testC("pushstring 10; pushstring 3; arith ^; return 1") == 1000)
+assert(T.testC("arith /; return 1", 2, 0) == 10.0/0)
+a = T.testC("pushnum 10; pushint 3; arith \\; return 1")
+assert(a == 3.0 and math.type(a) == "float")
+a = T.testC("pushint 10; pushint 3; arith \\; return 1")
+assert(a == 3 and math.type(a) == "integer")
+a = assert(T.testC("pushint 10; pushint 3; arith +; return 1"))
+assert(a == 13 and math.type(a) == "integer")
+a = assert(T.testC("pushnum 10; pushint 3; arith +; return 1"))
+assert(a == 13 and math.type(a) == "float")
+a,b,c = T.testC([[pushnum 1;
+                  pushstring 10; arith _;
+                  pushstring 5; return 3]])
+assert(a == 1 and b == -10 and c == "5")
+mt = {__add = function (a,b) return setmetatable({a[1] + b[1]}, mt) end,
+      __mod = function (a,b) return setmetatable({a[1] % b[1]}, mt) end,
+      __unm = function (a) return setmetatable({a[1]* 2}, mt) end}
+a,b,c = setmetatable({4}, mt),
+        setmetatable({8}, mt),
+        setmetatable({-3}, mt)
+x,y,z = T.testC("arith +; return 2", 10, a, b)
+assert(x == 10 and y[1] == 12 and z == nil)
+assert(T.testC("arith %; return 1", a, c)[1] == 4%-3)
+assert(T.testC("arith _; arith +; arith %; return 1", b, a, c)[1] ==
+               8 % (4 + (-3)*2))
+
+-- errors in arithmetic
+checkerr("divide by zero", T.testC, "arith \\", 10, 0)
+checkerr("%%0", T.testC, "arith %", 10, 0)
+
+
+-- testing lessthan and lessequal
+assert(T.testC("compare LT 2 5, return 1", 3, 2, 2, 4, 2, 2))
+assert(T.testC("compare LE 2 5, return 1", 3, 2, 2, 4, 2, 2))
+assert(not T.testC("compare LT 3 4, return 1", 3, 2, 2, 4, 2, 2))
+assert(T.testC("compare LE 3 4, return 1", 3, 2, 2, 4, 2, 2))
+assert(T.testC("compare LT 5 2, return 1", 4, 2, 2, 3, 2, 2))
+assert(not T.testC("compare LT 2 -3, return 1", "4", "2", "2", "3", "2", "2"))
+assert(not T.testC("compare LT -3 2, return 1", "3", "2", "2", "4", "2", "2"))
+
+-- non-valid indices produce false
+assert(not T.testC("compare LT 1 4, return 1"))
+assert(not T.testC("compare LE 9 1, return 1"))
+assert(not T.testC("compare EQ 9 9, return 1"))
+
+local b = {__lt = function (a,b) return a[1] < b[1] end}
+local a1,a3,a4 = setmetatable({1}, b),
+                 setmetatable({3}, b),
+                 setmetatable({4}, b)
+assert(T.testC("compare LT 2 5, return 1", a3, 2, 2, a4, 2, 2))
+assert(T.testC("compare LE 2 5, return 1", a3, 2, 2, a4, 2, 2))
+assert(T.testC("compare LT 5 -6, return 1", a4, 2, 2, a3, 2, 2))
+a,b = T.testC("compare LT 5 -6, return 2", a1, 2, 2, a3, 2, 20)
+assert(a == 20 and b == false)
+a,b = T.testC("compare LE 5 -6, return 2", a1, 2, 2, a3, 2, 20)
+assert(a == 20 and b == false)
+a,b = T.testC("compare LE 5 -6, return 2", a1, 2, 2, a1, 2, 20)
+assert(a == 20 and b == true)
+
+
+do  -- testing lessthan and lessequal with metamethods
+  local mt = {__lt = function (a,b) return a[1] < b[1] end,
+              __le = function (a,b) return a[1] <= b[1] end,
+              __eq = function (a,b) return a[1] == b[1] end}
+  local function O (x)
+    return setmetatable({x}, mt)
+  end
+
+  local a, b = T.testC("compare LT 2 3; pushint 10; return 2", O(1), O(2))
+  assert(a == true and b == 10)
+  local a, b = T.testC("compare LE 2 3; pushint 10; return 2", O(3), O(2))
+  assert(a == false and b == 10)
+  local a, b = T.testC("compare EQ 2 3; pushint 10; return 2", O(3), O(3))
+  assert(a == true and b == 10)
+end
+
+-- testing length
+local t = setmetatable({x = 20}, {__len = function (t) return t.x end})
+a,b,c = T.testC([[
+   len 2;
+   Llen 2;
+   objsize 2;
+   return 3
+]], t)
+assert(a == 20 and b == 20 and c == 0)
+
+t.x = "234"; t[1] = 20
+a,b,c = T.testC([[
+   len 2;
+   Llen 2;
+   objsize 2;
+   return 3
+]], t)
+assert(a == "234" and b == 234 and c == 1)
+
+t.x = print; t[1] = 20
+a,c = T.testC([[
+   len 2;
+   objsize 2;
+   return 2
+]], t)
+assert(a == print and c == 1)
+
+
+-- testing __concat
+
+a = setmetatable({x="u"}, {__concat = function (a,b) return a.x..'.'..b.x end})
+x,y = T.testC([[
+  pushnum 5
+  pushvalue 2;
+  pushvalue 2;
+  concat 2;
+  pushvalue -2;
+  return 2;
+]], a, a)
+assert(x == a..a and y == 5)
+
+-- concat with 0 elements
+assert(T.testC("concat 0; return 1") == "")
+
+-- concat with 1 element
+assert(T.testC("concat 1; return 1", "xuxu") == "xuxu")
+
+
+
+-- testing lua_is
+
+function B(x) return x and 1 or 0 end
+
+function count (x, n)
+  n = n or 2
+  local prog = [[
+    isnumber %d;
+    isstring %d;
+    isfunction %d;
+    iscfunction %d;
+    istable %d;
+    isuserdata %d;
+    isnil %d;
+    isnull %d;
+    return 8
+  ]]
+  prog = string.format(prog, n, n, n, n, n, n, n, n)
+  local a,b,c,d,e,f,g,h = T.testC(prog, x)
+  return B(a)+B(b)+B(c)+B(d)+B(e)+B(f)+B(g)+(100*B(h))
+end
+
+assert(count(3) == 2)
+assert(count('alo') == 1)
+assert(count('32') == 2)
+assert(count({}) == 1)
+assert(count(print) == 2)
+assert(count(function () end) == 1)
+assert(count(nil) == 1)
+assert(count(io.stdin) == 1)
+assert(count(nil, 15) == 100)
+
+
+-- testing lua_to...
+
+function to (s, x, n)
+  n = n or 2
+  return T.testC(string.format("%s %d; return 1", s, n), x)
+end
+
+local null = T.pushuserdata(0)
+local hfunc = string.gmatch("", "")    -- a "heavy C function" (with upvalues)
+assert(debug.getupvalue(hfunc, 1))
+assert(to("tostring", {}) == nil)
+assert(to("tostring", "alo") == "alo")
+assert(to("tostring", 12) == "12")
+assert(to("tostring", 12, 3) == nil)
+assert(to("objsize", {}) == 0)
+assert(to("objsize", {1,2,3}) == 3)
+assert(to("objsize", "alo\0\0a") == 6)
+assert(to("objsize", T.newuserdata(0)) == 0)
+assert(to("objsize", T.newuserdata(101)) == 101)
+assert(to("objsize", 124) == 0)
+assert(to("objsize", true) == 0)
+assert(to("tonumber", {}) == 0)
+assert(to("tonumber", "12") == 12)
+assert(to("tonumber", "s2") == 0)
+assert(to("tonumber", 1, 20) == 0)
+assert(to("topointer", 10) == null)
+assert(to("topointer", true) == null)
+assert(to("topointer", nil) == null)
+assert(to("topointer", "abc") ~= null)
+assert(to("topointer", string.rep("x", 10)) ==
+       to("topointer", string.rep("x", 10)))    -- short strings
+do    -- long strings
+  local s1 = string.rep("x", 300)
+  local s2 = string.rep("x", 300)
+  assert(to("topointer", s1) ~= to("topointer", s2))
+end
+assert(to("topointer", T.pushuserdata(20)) ~= null)
+assert(to("topointer", io.read) ~= null)           -- light C function
+assert(to("topointer", hfunc) ~= null)        -- "heavy" C function
+assert(to("topointer", function () end) ~= null)   -- Lua function
+assert(to("topointer", io.stdin) ~= null)   -- full userdata
+assert(to("func2num", 20) == 0)
+assert(to("func2num", T.pushuserdata(10)) == 0)
+assert(to("func2num", io.read) ~= 0)     -- light C function
+assert(to("func2num", hfunc) ~= 0)  -- "heavy" C function (with upvalue)
+a = to("tocfunction", math.deg)
+assert(a(3) == math.deg(3) and a == math.deg)
+
+
+print("testing panic function")
+do
+  -- trivial error
+  assert(T.checkpanic("pushstring hi; error") == "hi")
+
+  -- using the stack inside panic
+  assert(T.checkpanic("pushstring hi; error;",
+    [[checkstack 5 XX
+      pushstring ' alo'
+      pushstring ' mundo'
+      concat 3]]) == "hi alo mundo")
+
+  -- "argerror" without frames
+  assert(T.checkpanic("loadstring 4") ==
+      "bad argument #4 (string expected, got no value)")
+
+
+  -- memory error
+  T.totalmem(T.totalmem()+10000)   -- set low memory limit (+10k)
+  assert(T.checkpanic("newuserdata 20000") == "not enough memory")
+  T.totalmem(0)          -- restore high limit
+
+  -- stack error
+  if not _soft then
+    local msg = T.checkpanic[[
+      pushstring "function f() f() end"
+      loadstring -1; call 0 0
+      getglobal f; call 0 0
+    ]]
+    assert(string.find(msg, "stack overflow"))
+  end
+
+  -- exit in panic still close to-be-closed variables
+  assert(T.checkpanic([[
+    pushstring "return {__close = function () Y = 'ho'; end}"
+    newtable
+    loadstring -2
+    call 0 1
+    setmetatable -2
+    toclose -1
+    pushstring "hi"
+    error
+  ]],
+  [[
+    getglobal Y
+    concat 2         # concat original error with global Y
+  ]]) == "hiho")
+
+
+end
+
+-- testing deep C stack
+if not _soft then
+  print("testing stack overflow")
+  collectgarbage("stop")
+  checkerr("XXXX", T.testC, "checkstack 1000023 XXXX")   -- too deep
+  -- too deep (with no message)
+  checkerr("^stack overflow$", T.testC, "checkstack 1000023 ''")
+  local s = string.rep("pushnil;checkstack 1 XX;", 1000000)
+  checkerr("overflow", T.testC, s)
+  collectgarbage("restart")
+  print'+'
+end
+
+local lim = _soft and 500 or 12000
+local prog = {"checkstack " .. (lim * 2 + 100) .. "msg", "newtable"}
+for i = 1,lim do
+  prog[#prog + 1] = "pushnum " .. i
+  prog[#prog + 1] = "pushnum " .. i * 10
+end
+
+prog[#prog + 1] = "rawgeti R 2"   -- get global table in registry
+prog[#prog + 1] = "insert " .. -(2*lim + 2)
+
+for i = 1,lim do
+  prog[#prog + 1] = "settable " .. -(2*(lim - i + 1) + 1)
+end
+
+prog[#prog + 1] = "return 2"
+
+prog = table.concat(prog, ";")
+local g, t = T.testC(prog)
+assert(g == _G)
+for i = 1,lim do assert(t[i] == i*10); t[i] = undef end
+assert(next(t) == nil)
+prog, g, t = nil
+
+-- testing errors
+
+a = T.testC([[
+  loadstring 2; pcall 0 1 0;
+  pushvalue 3; insert -2; pcall 1 1 0;
+  pcall 0 0 0;
+  return 1
+]], "x=150", function (a) assert(a==nil); return 3 end)
+
+assert(type(a) == 'string' and x == 150)
+
+function check3(p, ...)
+  local arg = {...}
+  assert(#arg == 3)
+  assert(string.find(arg[3], p))
+end
+check3(":1:", T.testC("loadstring 2; return *", "x="))
+check3("%.", T.testC("loadfile 2; return *", "."))
+check3("xxxx", T.testC("loadfile 2; return *", "xxxx"))
+
+-- test errors in non protected threads
+function checkerrnopro (code, msg)
+  local th = coroutine.create(function () end)  -- create new thread
+  local stt, err = pcall(T.testC, th, code)   -- run code there
+  assert(not stt and string.find(err, msg))
+end
+
+if not _soft then
+  checkerrnopro("pushnum 3; call 0 0", "attempt to call")
+  print"testing stack overflow in unprotected thread"
+  function f () f() end
+  checkerrnopro("getglobal 'f'; call 0 0;", "stack overflow")
+end
+print"+"
+
+
+-- testing table access
+
+do   -- getp/setp
+  local a = {}
+  local a1 = T.testC("rawsetp 2 1; return 1", a, 20)
+  assert(a == a1)
+  assert(a[T.pushuserdata(1)] == 20)
+  local a1, res = T.testC("rawgetp -1 1; return 2", a)
+  assert(a == a1 and res == 20)
+end
+
+
+do  -- using the table itself as index
+  local a = {}
+  a[a] = 10
+  local prog = "gettable -1; return *"
+  local res = {T.testC(prog, a)}
+  assert(#res == 2 and res[1] == prog and res[2] == 10)
+
+  local prog = "settable -2; return *"
+  local res = {T.testC(prog, a, 20)}
+  assert(a[a] == 20)
+  assert(#res == 1 and res[1] == prog)
+
+  -- raw
+  a[a] = 10
+  local prog = "rawget -1; return *"
+  local res = {T.testC(prog, a)}
+  assert(#res == 2 and res[1] == prog and res[2] == 10)
+
+  local prog = "rawset -2; return *"
+  local res = {T.testC(prog, a, 20)}
+  assert(a[a] == 20)
+  assert(#res == 1 and res[1] == prog)
+
+  -- using the table as the value to set
+  local prog = "rawset -1; return *"
+  local res = {T.testC(prog, 30, a)}
+  assert(a[30] == a)
+  assert(#res == 1 and res[1] == prog)
+
+  local prog = "settable -1; return *"
+  local res = {T.testC(prog, 40, a)}
+  assert(a[40] == a)
+  assert(#res == 1 and res[1] == prog)
+
+  local prog = "rawseti -1 100; return *"
+  local res = {T.testC(prog, a)}
+  assert(a[100] == a)
+  assert(#res == 1 and res[1] == prog)
+
+  local prog = "seti -1 200; return *"
+  local res = {T.testC(prog, a)}
+  assert(a[200] == a)
+  assert(#res == 1 and res[1] == prog)
+end
+
+a = {x=0, y=12}
+x, y = T.testC("gettable 2; pushvalue 4; gettable 2; return 2",
+                a, 3, "y", 4, "x")
+assert(x == 0 and y == 12)
+T.testC("settable -5", a, 3, 4, "x", 15)
+assert(a.x == 15)
+a[a] = print
+x = T.testC("gettable 2; return 1", a)  -- table and key are the same object!
+assert(x == print)
+T.testC("settable 2", a, "x")    -- table and key are the same object!
+assert(a[a] == "x")
+
+b = setmetatable({p = a}, {})
+getmetatable(b).__index = function (t, i) return t.p[i] end
+k, x = T.testC("gettable 3, return 2", 4, b, 20, 35, "x")
+assert(x == 15 and k == 35)
+k = T.testC("getfield 2 y, return 1", b)
+assert(k == 12)
+getmetatable(b).__index = function (t, i) return a[i] end
+getmetatable(b).__newindex = function (t, i,v ) a[i] = v end
+y = T.testC("insert 2; gettable -5; return 1", 2, 3, 4, "y", b)
+assert(y == 12)
+k = T.testC("settable -5, return 1", b, 3, 4, "x", 16)
+assert(a.x == 16 and k == 4)
+a[b] = 'xuxu'
+y = T.testC("gettable 2, return 1", b)
+assert(y == 'xuxu')
+T.testC("settable 2", b, 19)
+assert(a[b] == 19)
+
+--
+do   -- testing getfield/setfield with long keys
+  local t = {_012345678901234567890123456789012345678901234567890123456789 = 32}
+  local a = T.testC([[
+    getfield 2 _012345678901234567890123456789012345678901234567890123456789
+    return 1
+  ]], t)
+  assert(a == 32)
+  local a = T.testC([[
+    pushnum 33
+    setglobal _012345678901234567890123456789012345678901234567890123456789
+  ]])
+  assert(_012345678901234567890123456789012345678901234567890123456789 == 33)
+  _012345678901234567890123456789012345678901234567890123456789 = nil
+end
+
+-- testing next
+a = {}
+t = pack(T.testC("next; return *", a, nil))
+tcheck(t, {n=1,a})
+a = {a=3}
+t = pack(T.testC("next; return *", a, nil))
+tcheck(t, {n=3,a,'a',3})
+t = pack(T.testC("next; pop 1; next; return *", a, nil))
+tcheck(t, {n=1,a})
+
+
+
+-- testing upvalues
+
+do
+  local A = T.testC[[ pushnum 10; pushnum 20; pushcclosure 2; return 1]]
+  t, b, c = A([[pushvalue U0; pushvalue U1; pushvalue U2; return 3]])
+  assert(b == 10 and c == 20 and type(t) == 'table')
+  a, b = A([[tostring U3; tonumber U4; return 2]])
+  assert(a == nil and b == 0)
+  A([[pushnum 100; pushnum 200; replace U2; replace U1]])
+  b, c = A([[pushvalue U1; pushvalue U2; return 2]])
+  assert(b == 100 and c == 200)
+  A([[replace U2; replace U1]], {x=1}, {x=2})
+  b, c = A([[pushvalue U1; pushvalue U2; return 2]])
+  assert(b.x == 1 and c.x == 2)
+  T.checkmemory()
+end
+
+
+-- testing absent upvalues from C-function pointers
+assert(T.testC[[isnull U1; return 1]] == true)
+assert(T.testC[[isnull U100; return 1]] == true)
+assert(T.testC[[pushvalue U1; return 1]] == nil)
+
+local f = T.testC[[ pushnum 10; pushnum 20; pushcclosure 2; return 1]]
+assert(T.upvalue(f, 1) == 10 and
+       T.upvalue(f, 2) == 20 and
+       T.upvalue(f, 3) == nil)
+T.upvalue(f, 2, "xuxu")
+assert(T.upvalue(f, 2) == "xuxu")
+
+
+-- large closures
+do
+  local A = "checkstack 300 msg;" ..
+            string.rep("pushnum 10;", 255) ..
+            "pushcclosure 255; return 1"
+  A = T.testC(A)
+  for i=1,255 do
+    assert(A(("pushvalue U%d; return 1"):format(i)) == 10)
+  end
+  assert(A("isnull U256; return 1"))
+  assert(not A("isnil U256; return 1"))
+end
+
+
+
+-- testing get/setuservalue
+-- bug in 5.1.2
+checkerr("got number", debug.setuservalue, 3, {})
+checkerr("got nil", debug.setuservalue, nil, {})
+checkerr("got light userdata", debug.setuservalue, T.pushuserdata(1), {})
+
+-- testing multiple user values
+local b = T.newuserdata(0, 10)
+for i = 1, 10 do
+  local v, p = debug.getuservalue(b, i)
+  assert(v == nil and p)
+end
+do   -- indices out of range
+  local v, p = debug.getuservalue(b, -2)
+  assert(v == nil and not p)
+  local v, p = debug.getuservalue(b, 11)
+  assert(v == nil and not p)
+end
+local t = {true, false, 4.56, print, {}, b, "XYZ"}
+for k, v in ipairs(t) do
+  debug.setuservalue(b, v, k)
+end
+for k, v in ipairs(t) do
+  local v1, p = debug.getuservalue(b, k)
+  assert(v1 == v and p)
+end
+
+assert(not debug.getuservalue(4))
+
+debug.setuservalue(b, function () return 10 end, 10)
+collectgarbage()   -- function should not be collected
+assert(debug.getuservalue(b, 10)() == 10)
+
+debug.setuservalue(b, 134)
+collectgarbage()   -- number should not be a problem for collector
+assert(debug.getuservalue(b) == 134)
+
+
+-- test barrier for uservalues
+do
+  local oldmode = collectgarbage("incremental")
+  T.gcstate("atomic")
+  assert(T.gccolor(b) == "black")
+  debug.setuservalue(b, {x = 100})
+  T.gcstate("pause")  -- complete collection
+  assert(debug.getuservalue(b).x == 100)  -- uvalue should be there
+  collectgarbage(oldmode)
+end
+
+-- long chain of userdata
+for i = 1, 1000 do
+  local bb = T.newuserdata(0, 1)
+  debug.setuservalue(bb, b)
+  b = bb
+end
+collectgarbage()     -- nothing should not be collected
+for i = 1, 1000 do
+  b = debug.getuservalue(b)
+end
+assert(debug.getuservalue(b).x == 100)
+b = nil
+
+
+-- testing locks (refs)
+
+-- reuse of references
+local i = T.ref{}
+T.unref(i)
+assert(T.ref{} == i)
+
+Arr = {}
+Lim = 100
+for i=1,Lim do   -- lock many objects
+  Arr[i] = T.ref({})
+end
+
+assert(T.ref(nil) == -1 and T.getref(-1) == nil)
+T.unref(-1); T.unref(-1)
+
+for i=1,Lim do   -- unlock all them
+  T.unref(Arr[i])
+end
+
+function printlocks ()
+  local f = T.makeCfunc("gettable R; return 1")
+  local n = f("n")
+  print("n", n)
+  for i=0,n do
+    print(i, f(i))
+  end
+end
+
+
+for i=1,Lim do   -- lock many objects
+  Arr[i] = T.ref({})
+end
+
+for i=1,Lim,2 do   -- unlock half of them
+  T.unref(Arr[i])
+end
+
+assert(type(T.getref(Arr[2])) == 'table')
+
+
+assert(T.getref(-1) == nil)
+
+
+a = T.ref({})
+
+collectgarbage()
+
+assert(type(T.getref(a)) == 'table')
+
+
+-- colect in cl the `val' of all collected userdata
+tt = {}
+cl = {n=0}
+A = nil; B = nil
+local F
+F = function (x)
+  local udval = T.udataval(x)
+  table.insert(cl, udval)
+  local d = T.newuserdata(100)   -- create garbage
+  d = nil
+  assert(debug.getmetatable(x).__gc == F)
+  assert(load("table.insert({}, {})"))()   -- create more garbage
+  collectgarbage()   -- force a GC during GC
+  assert(debug.getmetatable(x).__gc == F)  -- previous GC did not mess this?
+  local dummy = {}    -- create more garbage during GC
+  if A ~= nil then
+    assert(type(A) == "userdata")
+    assert(T.udataval(A) == B)
+    debug.getmetatable(A)    -- just access it
+  end
+  A = x   -- ressucita userdata
+  B = udval
+  return 1,2,3
+end
+tt.__gc = F
+
+-- test whether udate collection frees memory in the right time
+do
+  collectgarbage();
+  collectgarbage();
+  local x = collectgarbage("count");
+  local a = T.newuserdata(5001)
+  assert(T.testC("objsize 2; return 1", a) == 5001)
+  assert(collectgarbage("count") >= x+4)
+  a = nil
+  collectgarbage();
+  assert(collectgarbage("count") <= x+1)
+  -- udata without finalizer
+  x = collectgarbage("count")
+  collectgarbage("stop")
+  for i=1,1000 do T.newuserdata(0) end
+  assert(collectgarbage("count") > x+10)
+  collectgarbage()
+  assert(collectgarbage("count") <= x+1)
+  -- udata with finalizer
+  collectgarbage()
+  x = collectgarbage("count")
+  collectgarbage("stop")
+  a = {__gc = function () end}
+  for i=1,1000 do debug.setmetatable(T.newuserdata(0), a) end
+  assert(collectgarbage("count") >= x+10)
+  collectgarbage()  -- this collection only calls TM, without freeing memory
+  assert(collectgarbage("count") >= x+10)
+  collectgarbage()  -- now frees memory
+  assert(collectgarbage("count") <= x+1)
+  collectgarbage("restart")
+end
+
+
+collectgarbage("stop")
+
+-- create 3 userdatas with tag `tt'
+a = T.newuserdata(0); debug.setmetatable(a, tt); na = T.udataval(a)
+b = T.newuserdata(0); debug.setmetatable(b, tt); nb = T.udataval(b)
+c = T.newuserdata(0); debug.setmetatable(c, tt); nc = T.udataval(c)
+
+-- create userdata without meta table
+x = T.newuserdata(4)
+y = T.newuserdata(0)
+
+checkerr("FILE%* expected, got userdata", io.input, a)
+checkerr("FILE%* expected, got userdata", io.input, x)
+
+assert(debug.getmetatable(x) == nil and debug.getmetatable(y) == nil)
+
+d=T.ref(a);
+e=T.ref(b);
+f=T.ref(c);
+t = {T.getref(d), T.getref(e), T.getref(f)}
+assert(t[1] == a and t[2] == b and t[3] == c)
+
+t=nil; a=nil; c=nil;
+T.unref(e); T.unref(f)
+
+collectgarbage()
+
+-- check that unref objects have been collected
+assert(#cl == 1 and cl[1] == nc)
+
+x = T.getref(d)
+assert(type(x) == 'userdata' and debug.getmetatable(x) == tt)
+x =nil
+tt.b = b  -- create cycle
+tt=nil    -- frees tt for GC
+A = nil
+b = nil
+T.unref(d);
+n5 = T.newuserdata(0)
+debug.setmetatable(n5, {__gc=F})
+n5 = T.udataval(n5)
+collectgarbage()
+assert(#cl == 4)
+-- check order of collection
+assert(cl[2] == n5 and cl[3] == nb and cl[4] == na)
+
+collectgarbage"restart"
+
+
+a, na = {}, {}
+for i=30,1,-1 do
+  a[i] = T.newuserdata(0)
+  debug.setmetatable(a[i], {__gc=F})
+  na[i] = T.udataval(a[i])
+end
+cl = {}
+a = nil; collectgarbage()
+assert(#cl == 30)
+for i=1,30 do assert(cl[i] == na[i]) end
+na = nil
+
+
+for i=2,Lim,2 do   -- unlock the other half
+  T.unref(Arr[i])
+end
+
+x = T.newuserdata(41); debug.setmetatable(x, {__gc=F})
+assert(T.testC("objsize 2; return 1", x) == 41)
+cl = {}
+a = {[x] = 1}
+x = T.udataval(x)
+collectgarbage()
+-- old `x' cannot be collected (`a' still uses it)
+assert(#cl == 0)
+for n in pairs(a) do a[n] = undef end
+collectgarbage()
+assert(#cl == 1 and cl[1] == x)   -- old `x' must be collected
+
+-- testing lua_equal
+assert(T.testC("compare EQ 2 4; return 1", print, 1, print, 20))
+assert(T.testC("compare EQ 3 2; return 1", 'alo', "alo"))
+assert(T.testC("compare EQ 2 3; return 1", nil, nil))
+assert(not T.testC("compare EQ 2 3; return 1", {}, {}))
+assert(not T.testC("compare EQ 2 3; return 1"))
+assert(not T.testC("compare EQ 2 3; return 1", 3))
+
+-- testing lua_equal with fallbacks
+do
+  local map = {}
+  local t = {__eq = function (a,b) return map[a] == map[b] end}
+  local function f(x)
+    local u = T.newuserdata(0)
+    debug.setmetatable(u, t)
+    map[u] = x
+    return u
+  end
+  assert(f(10) == f(10))
+  assert(f(10) ~= f(11))
+  assert(T.testC("compare EQ 2 3; return 1", f(10), f(10)))
+  assert(not T.testC("compare EQ 2 3; return 1", f(10), f(20)))
+  t.__eq = nil
+  assert(f(10) ~= f(10))
+end
+
+print'+'
+
+
+
+-- testing changing hooks during hooks
+_G.t = {}
+T.sethook([[
+  # set a line hook after 3 count hooks
+  sethook 4 0 '
+    getglobal t;
+    pushvalue -3; append -2
+    pushvalue -2; append -2
+  ']], "c", 3)
+local a = 1   -- counting
+a = 1   -- counting
+a = 1   -- count hook (set line hook)
+a = 1   -- line hook
+a = 1   -- line hook
+debug.sethook()
+t = _G.t
+assert(t[1] == "line")
+line = t[2]
+assert(t[3] == "line" and t[4] == line + 1)
+assert(t[5] == "line" and t[6] == line + 2)
+assert(t[7] == nil)
+
+
+-------------------------------------------------------------------------
+do   -- testing errors during GC
+  warn("@off")
+  collectgarbage("stop")
+  local a = {}
+  for i=1,20 do
+    a[i] = T.newuserdata(i)   -- creates several udata
+  end
+  for i=1,20,2 do   -- mark half of them to raise errors during GC
+    debug.setmetatable(a[i],
+      {__gc = function (x) error("@expected error in gc") end})
+  end
+  for i=2,20,2 do   -- mark the other half to count and to create more garbage
+    debug.setmetatable(a[i], {__gc = function (x) load("A=A+1")() end})
+  end
+  a = nil
+  _G.A = 0
+  collectgarbage()
+  assert(A == 10)  -- number of normal collections
+  collectgarbage("restart")
+  warn("@on")
+end
+-------------------------------------------------------------------------
+-- test for userdata vals
+do
+  local a = {}; local lim = 30
+  for i=0,lim do a[i] = T.pushuserdata(i) end
+  for i=0,lim do assert(T.udataval(a[i]) == i) end
+  for i=0,lim do assert(T.pushuserdata(i) == a[i]) end
+  for i=0,lim do a[a[i]] = i end
+  for i=0,lim do a[T.pushuserdata(i)] = i end
+  assert(type(tostring(a[1])) == "string")
+end
+
+
+-------------------------------------------------------------------------
+-- testing multiple states
+T.closestate(T.newstate());
+L1 = T.newstate()
+assert(L1)
+
+assert(T.doremote(L1, "X='a'; return 'a'") == 'a')
+
+
+assert(#pack(T.doremote(L1, "function f () return 'alo', 3 end; f()")) == 0)
+
+a, b = T.doremote(L1, "return f()")
+assert(a == 'alo' and b == '3')
+
+T.doremote(L1, "_ERRORMESSAGE = nil")
+-- error: `sin' is not defined
+a, _, b = T.doremote(L1, "return sin(1)")
+assert(a == nil and b == 2)   -- 2 == run-time error
+
+-- error: syntax error
+a, b, c = T.doremote(L1, "return a+")
+assert(a == nil and c == 3 and type(b) == "string")   -- 3 == syntax error
+
+T.loadlib(L1)
+a, b, c = T.doremote(L1, [[
+  string = require'string'
+  a = require'_G'; assert(a == _G and require("_G") == a)
+  io = require'io'; assert(type(io.read) == "function")
+  assert(require("io") == io)
+  a = require'table'; assert(type(a.insert) == "function")
+  a = require'debug'; assert(type(a.getlocal) == "function")
+  a = require'math'; assert(type(a.sin) == "function")
+  return string.sub('okinama', 1, 2)
+]])
+assert(a == "ok")
+
+T.closestate(L1);
+
+
+L1 = T.newstate()
+T.loadlib(L1)
+T.doremote(L1, "a = {}")
+T.testC(L1, [[getglobal "a"; pushstring "x"; pushint 1;
+             settable -3]])
+assert(T.doremote(L1, "return a.x") == "1")
+
+T.closestate(L1)
+
+L1 = nil
+
+print('+')
+-------------------------------------------------------------------------
+-- testing to-be-closed variables
+-------------------------------------------------------------------------
+print"testing to-be-closed variables"
+
+do
+  local openresource = {}
+
+  local function newresource ()
+    local x = setmetatable({10}, {__close = function(y)
+      assert(openresource[#openresource] == y)
+      openresource[#openresource] = nil
+      y[1] = y[1] + 1
+    end})
+    openresource[#openresource + 1] = x
+    return x
+  end
+
+  local a, b = T.testC([[
+    call 0 1   # create resource
+    pushnil
+    toclose -2  # mark call result to be closed
+    toclose -1  # mark nil to be closed (will be ignored)
+    return 2
+  ]], newresource)
+  assert(a[1] == 11 and b == nil)
+  assert(#openresource == 0)    -- was closed
+
+  -- repeat the test, but calling function in a 'multret' context
+  local a = {T.testC([[
+    call 0 1   # create resource
+    toclose 2 # mark it to be closed
+    return 2
+  ]], newresource)}
+  assert(type(a[1]) == "string" and a[2][1] == 11)
+  assert(#openresource == 0)    -- was closed
+
+  -- closing by error
+  local a, b = pcall(T.makeCfunc[[
+    call 0 1   # create resource
+    toclose -1 # mark it to be closed
+    error       # resource is the error object
+  ]], newresource)
+  assert(a == false and b[1] == 11)
+  assert(#openresource == 0)    -- was closed
+
+  -- non-closable value
+  local a, b = pcall(T.makeCfunc[[
+    newtable   # create non-closable object
+    toclose -1 # mark it to be closed (should raise an error)
+    abort  # will not be executed
+  ]])
+  assert(a == false and
+    string.find(b, "non%-closable value"))
+
+  local function check (n)
+    assert(#openresource == n)
+  end
+
+  -- closing resources with 'settop'
+  local a = T.testC([[
+    pushvalue 2
+    call 0 1   # create resource
+    toclose -1 # mark it to be closed
+    pushvalue 2
+    call 0 1   # create another resource
+    toclose -1 # mark it to be closed
+    pushvalue 3
+    pushint 2   # there should be two open resources
+    call 1 0
+    pop 1       # pop second resource from the stack
+    pushvalue 3
+    pushint 1   # there should be one open resource
+    call 1 0
+    pop 1       # pop second resource from the stack
+    pushint *
+    return 1    # return stack size
+  ]], newresource, check)
+  assert(a == 3)   -- no extra items left in the stack
+
+  -- non-closable value
+  local a, b = pcall(T.makeCfunc[[
+    pushint 32
+    toclose -1
+  ]])
+  assert(not a and string.find(b, "(C temporary)"))
+
+end
+
+
+-------------------------------------------------------------------------
+-- testing memory limits
+-------------------------------------------------------------------------
+print("memory-allocation errors")
+
+checkerr("block too big", T.newuserdata, math.maxinteger)
+collectgarbage()
+local f = load"local a={}; for i=1,100000 do a[i]=i end"
+T.alloccount(10)
+checkerr("not enough memory", f)
+T.alloccount()          -- remove limit
+
+-- test memory errors; increase limit for number of allocations one
+-- by one, so that we get memory errors in all allocations of a given
+-- task, until there is enough allocations to complete the task without
+-- errors.
+
+function testamem (s, f)
+  collectgarbage(); collectgarbage()
+  local M = 0
+  local a,b = nil
+  while true do
+    T.alloccount(M)
+    a, b = pcall(f)
+    T.alloccount()  -- remove limit
+    if a and b then break end       -- stop when no more errors
+    if not a and not    -- `real' error?
+      (string.find(b, "memory") or string.find(b, "overflow")) then
+      error(b, 0)   -- propagate it
+    end
+    M = M + 1   -- increase allocation limit
+  end
+  print(string.format("limit for %s: %d allocations", s, M))
+  return b
+end
+
+
+-- doing nothing
+b = testamem("doing nothing", function () return 10 end)
+assert(b == 10)
+
+-- testing memory errors when creating a new state
+
+b = testamem("state creation", T.newstate)
+T.closestate(b);  -- close new state
+
+testamem("empty-table creation", function ()
+  return {}
+end)
+
+testamem("string creation", function ()
+  return "XXX" .. "YYY"
+end)
+
+testamem("coroutine creation", function()
+           return coroutine.create(print)
+end)
+
+
+-- testing to-be-closed variables
+testamem("to-be-closed variables", function()
+  local flag
+  do
+    local x <close> =
+              setmetatable({}, {__close = function () flag = true end})
+    flag = false
+    local x = {}
+  end
+  return flag
+end)
+
+
+-- testing threads
+
+-- get main thread from registry (at index LUA_RIDX_MAINTHREAD == 1)
+mt = T.testC("rawgeti R 1; return 1")
+assert(type(mt) == "thread" and coroutine.running() == mt)
+
+
+
+function expand (n,s)
+  if n==0 then return "" end
+  local e = string.rep("=", n)
+  return string.format("T.doonnewstack([%s[ %s;\n collectgarbage(); %s]%s])\n",
+                              e, s, expand(n-1,s), e)
+end
+
+G=0; collectgarbage(); a =collectgarbage("count")
+load(expand(20,"G=G+1"))()
+assert(G==20); collectgarbage();  -- assert(gcinfo() <= a+1)
+
+testamem("running code on new thread", function ()
+  return T.doonnewstack("x=1") == 0  -- try to create thread
+end)
+
+
+-- testing memory x compiler
+
+testamem("loadstring", function ()
+  return load("x=1")  -- try to do load a string
+end)
+
+
+local testprog = [[
+local function foo () return end
+local t = {"x"}
+a = "aaa"
+for i = 1, #t do a=a..t[i] end
+return true
+]]
+
+-- testing memory x dofile
+_G.a = nil
+local t =os.tmpname()
+local f = assert(io.open(t, "w"))
+f:write(testprog)
+f:close()
+testamem("dofile", function ()
+  local a = loadfile(t)
+  return a and a()
+end)
+assert(os.remove(t))
+assert(_G.a == "aaax")
+
+
+-- other generic tests
+
+testamem("gsub", function ()
+  local a, b = string.gsub("alo alo", "(a)", function (x) return x..'b' end)
+  return (a == 'ablo ablo')
+end)
+
+testamem("dump/undump", function ()
+  local a = load(testprog)
+  local b = a and string.dump(a)
+  a = b and load(b)
+  return a and a()
+end)
+
+local t = os.tmpname()
+testamem("file creation", function ()
+  local f = assert(io.open(t, 'w'))
+  assert (not io.open"nomenaoexistente")
+  io.close(f);
+  return not loadfile'nomenaoexistente'
+end)
+assert(os.remove(t))
+
+testamem("table creation", function ()
+  local a, lim = {}, 10
+  for i=1,lim do a[i] = i; a[i..'a'] = {} end
+  return (type(a[lim..'a']) == 'table' and a[lim] == lim)
+end)
+
+testamem("constructors", function ()
+  local a = {10, 20, 30, 40, 50; a=1, b=2, c=3, d=4, e=5}
+  return (type(a) == 'table' and a.e == 5)
+end)
+
+local a = 1
+close = nil
+testamem("closure creation", function ()
+  function close (b)
+   return function (x) return b + x end
+  end
+  return (close(2)(4) == 6)
+end)
+
+testamem("using coroutines", function ()
+  local a = coroutine.wrap(function ()
+              coroutine.yield(string.rep("a", 10))
+              return {}
+            end)
+  assert(string.len(a()) == 10)
+  return a()
+end)
+
+do   -- auxiliary buffer
+  local lim = 100
+  local a = {}; for i = 1, lim do a[i] = "01234567890123456789" end
+  testamem("auxiliary buffer", function ()
+    return (#table.concat(a, ",") == 20*lim + lim - 1)
+  end)
+end
+
+testamem("growing stack", function ()
+  local function foo (n)
+    if n == 0 then return 1 else return 1 + foo(n - 1) end
+  end
+  return foo(100)
+end)
+
+do   -- testing failing in 'lua_checkstack'
+  local res = T.testC([[rawcheckstack 500000; return 1]])
+  assert(res == false)
+  local L = T.newstate()
+  T.alloccount(0)   -- will be unable to reallocate the stack
+  res = T.testC(L, [[rawcheckstack 5000; return 1]])
+  T.alloccount()
+  T.closestate(L)
+  assert(res == false)
+end
+
+do   -- closing state with no extra memory
+  local L = T.newstate()
+  T.alloccount(0)
+  T.closestate(L)
+  T.alloccount()
+end
+
+do   -- garbage collection with no extra memory
+  local L = T.newstate()
+  T.loadlib(L)
+  local res = (T.doremote(L, [[
+    _ENV = require"_G"
+    local T = require"T"
+    local a = {}
+    for i = 1, 1000 do a[i] = 'i' .. i end    -- grow string table
+    local stsize, stuse = T.querystr()
+    assert(stuse > 1000)
+    local function foo (n)
+      if n > 0 then foo(n - 1) end
+    end
+    foo(180)    -- grow stack
+    local _, stksize = T.stacklevel()
+    assert(stksize > 180)
+    a = nil
+    T.alloccount(0)
+    collectgarbage()
+    T.alloccount()
+    -- stack and string table could not be reallocated,
+    -- so they kept their sizes (without errors)
+    assert(select(2, T.stacklevel()) == stksize)
+    assert(T.querystr() == stsize)
+    return 'ok'
+  ]]))
+  assert(res == 'ok')
+  T.closestate(L)
+end
+
+print'+'
+
+-- testing some auxlib functions
+local function gsub (a, b, c)
+  a, b = T.testC("gsub 2 3 4; gettop; return 2", a, b, c)
+  assert(b == 5)
+  return a
+end
+
+assert(gsub("alo.alo.uhuh.", ".", "//") == "alo//alo//uhuh//")
+assert(gsub("alo.alo.uhuh.", "alo", "//") == "//.//.uhuh.")
+assert(gsub("", "alo", "//") == "")
+assert(gsub("...", ".", "/.") == "/././.")
+assert(gsub("...", "...", "") == "")
+
+
+-- testing luaL_newmetatable
+local mt_xuxu, res, top = T.testC("newmetatable xuxu; gettop; return 3")
+assert(type(mt_xuxu) == "table" and res and top == 3)
+local d, res, top = T.testC("newmetatable xuxu; gettop; return 3")
+assert(mt_xuxu == d and not res and top == 3)
+d, res, top = T.testC("newmetatable xuxu1; gettop; return 3")
+assert(mt_xuxu ~= d and res and top == 3)
+
+x = T.newuserdata(0);
+y = T.newuserdata(0);
+T.testC("pushstring xuxu; gettable R; setmetatable 2", x)
+assert(getmetatable(x) == mt_xuxu)
+
+-- testing luaL_testudata
+-- correct metatable
+local res1, res2, top = T.testC([[testudata -1 xuxu
+   	 			  testudata 2 xuxu
+				  gettop
+				  return 3]], x)
+assert(res1 and res2 and top == 4)
+
+-- wrong metatable
+res1, res2, top = T.testC([[testudata -1 xuxu1
+			    testudata 2 xuxu1
+			    gettop
+			    return 3]], x)
+assert(not res1 and not res2 and top == 4)
+
+-- non-existent type
+res1, res2, top = T.testC([[testudata -1 xuxu2
+			    testudata 2 xuxu2
+			    gettop
+			    return 3]], x)
+assert(not res1 and not res2 and top == 4)
+
+-- userdata has no metatable
+res1, res2, top = T.testC([[testudata -1 xuxu
+			    testudata 2 xuxu
+			    gettop
+			    return 3]], y)
+assert(not res1 and not res2 and top == 4)
+
+-- erase metatables
+do
+  local r = debug.getregistry()
+  assert(r.xuxu == mt_xuxu and r.xuxu1 == d)
+  r.xuxu = nil; r.xuxu1 = nil
+end
+
+print'OK'
+
diff --git a/test/external/lua-5.4.0-tests/attrib.lua b/test/external/lua-5.4.0-tests/attrib.lua
new file mode 100644
index 0000000..b1076c7
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/attrib.lua
@@ -0,0 +1,515 @@
+-- $Id: testes/attrib.lua $
+-- See Copyright Notice in file all.lua
+
+print "testing require"
+
+assert(require"string" == string)
+assert(require"math" == math)
+assert(require"table" == table)
+assert(require"io" == io)
+assert(require"os" == os)
+assert(require"coroutine" == coroutine)
+
+assert(type(package.path) == "string")
+assert(type(package.cpath) == "string")
+assert(type(package.loaded) == "table")
+assert(type(package.preload) == "table")
+
+assert(type(package.config) == "string")
+print("package config: "..string.gsub(package.config, "\n", "|"))
+
+do
+  -- create a path with 'max' templates,
+  -- each with 1-10 repetitions of '?'
+  local max = _soft and 100 or 2000
+  local t = {}
+  for i = 1,max do t[i] = string.rep("?", i%10 + 1) end
+  t[#t + 1] = ";"    -- empty template
+  local path = table.concat(t, ";")
+  -- use that path in a search
+  local s, err = package.searchpath("xuxu", path)
+  -- search fails; check that message has an occurrence of
+  -- '??????????' with ? replaced by xuxu and at least 'max' lines
+  assert(not s and
+         string.find(err, string.rep("xuxu", 10)) and
+         #string.gsub(err, "[^\n]", "") >= max)
+  -- path with one very long template
+  local path = string.rep("?", max)
+  local s, err = package.searchpath("xuxu", path)
+  assert(not s and string.find(err, string.rep('xuxu', max)))
+end
+
+do
+  local oldpath = package.path
+  package.path = {}
+  local s, err = pcall(require, "no-such-file")
+  assert(not s and string.find(err, "package.path"))
+  package.path = oldpath
+end
+
+
+do  print"testing 'require' message"
+  local oldpath = package.path
+  local oldcpath = package.cpath
+
+  package.path = "?.lua;?/?"
+  package.cpath = "?.so;?/init"
+
+  local st, msg = pcall(require, 'XXX')
+
+  local expected = [[module 'XXX' not found:
+	no field package.preload['XXX']
+	no file 'XXX.lua'
+	no file 'XXX/XXX'
+	no file 'XXX.so'
+	no file 'XXX/init']]
+
+  assert(msg == expected)
+
+  package.path = oldpath
+  package.cpath = oldcpath
+end
+
+print('+')
+
+
+-- The next tests for 'require' assume some specific directories and
+-- libraries.
+
+if not _port then --[
+
+local dirsep = string.match(package.config, "^([^\n]+)\n")
+
+-- auxiliary directory with C modules and temporary files
+local DIR = "libs" .. dirsep
+
+-- prepend DIR to a name and correct directory separators
+local function D (x)
+  x = string.gsub(x, "/", dirsep)
+  return DIR .. x
+end
+
+-- prepend DIR and pospend proper C lib. extension to a name
+local function DC (x)
+  local ext = (dirsep == '\\') and ".dll" or ".so"
+  return D(x .. ext)
+end
+
+
+local function createfiles (files, preextras, posextras)
+  for n,c in pairs(files) do
+    io.output(D(n))
+    io.write(string.format(preextras, n))
+    io.write(c)
+    io.write(string.format(posextras, n))
+    io.close(io.output())
+  end
+end
+
+function removefiles (files)
+  for n in pairs(files) do
+    os.remove(D(n))
+  end
+end
+
+local files = {
+  ["names.lua"] = "do return {...} end\n",
+  ["err.lua"] = "B = 15; a = a + 1;",
+  ["synerr.lua"] = "B =",
+  ["A.lua"] = "",
+  ["B.lua"] = "assert(...=='B');require 'A'",
+  ["A.lc"] = "",
+  ["A"] = "",
+  ["L"] = "",
+  ["XXxX"] = "",
+  ["C.lua"] = "package.loaded[...] = 25; require'C'",
+}
+
+AA = nil
+local extras = [[
+NAME = '%s'
+REQUIRED = ...
+return AA]]
+
+createfiles(files, "", extras)
+
+-- testing explicit "dir" separator in 'searchpath'
+assert(package.searchpath("C.lua", D"?", "", "") == D"C.lua")
+assert(package.searchpath("C.lua", D"?", ".", ".") == D"C.lua")
+assert(package.searchpath("--x-", D"?", "-", "X") == D"XXxX")
+assert(package.searchpath("---xX", D"?", "---", "XX") == D"XXxX")
+assert(package.searchpath(D"C.lua", "?", dirsep) == D"C.lua")
+assert(package.searchpath(".\\C.lua", D"?", "\\") == D"./C.lua")
+
+local oldpath = package.path
+
+package.path = string.gsub("D/?.lua;D/?.lc;D/?;D/??x?;D/L", "D/", DIR)
+
+local try = function (p, n, r, ext)
+  NAME = nil
+  local rr, x = require(p)
+  assert(NAME == n)
+  assert(REQUIRED == p)
+  assert(rr == r)
+  assert(ext == x)
+end
+
+a = require"names"
+assert(a[1] == "names" and a[2] == D"names.lua")
+
+_G.a = nil
+local st, msg = pcall(require, "err")
+assert(not st and string.find(msg, "arithmetic") and B == 15)
+st, msg = pcall(require, "synerr")
+assert(not st and string.find(msg, "error loading module"))
+
+assert(package.searchpath("C", package.path) == D"C.lua")
+assert(require"C" == 25)
+assert(require"C" == 25)
+AA = nil
+try('B', 'B.lua', true, "libs/B.lua")
+assert(package.loaded.B)
+assert(require"B" == true)
+assert(package.loaded.A)
+assert(require"C" == 25)
+package.loaded.A = nil
+try('B', nil, true, nil)   -- should not reload package
+try('A', 'A.lua', true, "libs/A.lua")
+package.loaded.A = nil
+os.remove(D'A.lua')
+AA = {}
+try('A', 'A.lc', AA, "libs/A.lc")  -- now must find second option
+assert(package.searchpath("A", package.path) == D"A.lc")
+assert(require("A") == AA)
+AA = false
+try('K', 'L', false, "libs/L")     -- default option
+try('K', 'L', false, "libs/L")     -- default option (should reload it)
+assert(rawget(_G, "_REQUIREDNAME") == nil)
+
+AA = "x"
+try("X", "XXxX", AA, "libs/XXxX")
+
+
+removefiles(files)
+
+
+-- testing require of sub-packages
+
+local _G = _G
+
+package.path = string.gsub("D/?.lua;D/?/init.lua", "D/", DIR)
+
+files = {
+  ["P1/init.lua"] = "AA = 10",
+  ["P1/xuxu.lua"] = "AA = 20",
+}
+
+createfiles(files, "_ENV = {}\n", "\nreturn _ENV\n")
+AA = 0
+
+local m, ext = assert(require"P1")
+assert(ext == "libs/P1/init.lua")
+assert(AA == 0 and m.AA == 10)
+assert(require"P1" == m)
+assert(require"P1" == m)
+
+assert(package.searchpath("P1.xuxu", package.path) == D"P1/xuxu.lua")
+m.xuxu, ext = assert(require"P1.xuxu")
+assert(AA == 0 and m.xuxu.AA == 20)
+assert(ext == "libs/P1/xuxu.lua")
+assert(require"P1.xuxu" == m.xuxu)
+assert(require"P1.xuxu" == m.xuxu)
+assert(require"P1" == m and m.AA == 10)
+
+
+removefiles(files)
+
+
+package.path = ""
+assert(not pcall(require, "file_does_not_exist"))
+package.path = "??\0?"
+assert(not pcall(require, "file_does_not_exist1"))
+
+package.path = oldpath
+
+-- check 'require' error message
+local fname = "file_does_not_exist2"
+local m, err = pcall(require, fname)
+for t in string.gmatch(package.path..";"..package.cpath, "[^;]+") do
+  t = string.gsub(t, "?", fname)
+  assert(string.find(err, t, 1, true))
+end
+
+do  -- testing 'package.searchers' not being a table
+  local searchers = package.searchers
+  package.searchers = 3
+  local st, msg = pcall(require, 'a')
+  assert(not st and string.find(msg, "must be a table"))
+  package.searchers = searchers
+end
+
+local function import(...)
+  local f = {...}
+  return function (m)
+    for i=1, #f do m[f[i]] = _G[f[i]] end
+  end
+end
+
+-- cannot change environment of a C function
+assert(not pcall(module, 'XUXU'))
+
+
+
+-- testing require of C libraries
+
+
+local p = ""   -- On Mac OS X, redefine this to "_"
+
+-- check whether loadlib works in this system
+local st, err, when = package.loadlib(DC"lib1", "*")
+if not st then
+  local f, err, when = package.loadlib("donotexist", p.."xuxu")
+  assert(not f and type(err) == "string" and when == "absent")
+  ;(Message or print)('\n >>> cannot load dynamic library <<<\n')
+  print(err, when)
+else
+  -- tests for loadlib
+  local f = assert(package.loadlib(DC"lib1", p.."onefunction"))
+  local a, b = f(15, 25)
+  assert(a == 25 and b == 15)
+
+  f = assert(package.loadlib(DC"lib1", p.."anotherfunc"))
+  assert(f(10, 20) == "10%20\n")
+
+  -- check error messages
+  local f, err, when = package.loadlib(DC"lib1", p.."xuxu")
+  assert(not f and type(err) == "string" and when == "init")
+  f, err, when = package.loadlib("donotexist", p.."xuxu")
+  assert(not f and type(err) == "string" and when == "open")
+
+  -- symbols from 'lib1' must be visible to other libraries
+  f = assert(package.loadlib(DC"lib11", p.."luaopen_lib11"))
+  assert(f() == "exported")
+
+  -- test C modules with prefixes in names
+  package.cpath = DC"?"
+  local lib2, ext = require"lib2-v2"
+  assert(string.find(ext, "libs/lib2-v2", 1, true))
+  -- check correct access to global environment and correct
+  -- parameters
+  assert(_ENV.x == "lib2-v2" and _ENV.y == DC"lib2-v2")
+  assert(lib2.id("x") == true)   -- a different "id" implementation
+
+  -- test C submodules
+  local fs, ext = require"lib1.sub"
+  assert(_ENV.x == "lib1.sub" and _ENV.y == DC"lib1")
+  assert(string.find(ext, "libs/lib1", 1, true))
+  assert(fs.id(45) == 45)
+end
+
+_ENV = _G
+
+
+-- testing preload
+
+do
+  local p = package
+  package = {}
+  p.preload.pl = function (...)
+    local _ENV = {...}
+    function xuxu (x) return x+20 end
+    return _ENV
+  end
+
+  local pl, ext = require"pl"
+  assert(require"pl" == pl)
+  assert(pl.xuxu(10) == 30)
+  assert(pl[1] == "pl" and pl[2] == ":preload:" and ext == ":preload:")
+
+  package = p
+  assert(type(package.path) == "string")
+end
+
+print('+')
+
+end  --]
+
+print("testing assignments, logical operators, and constructors")
+
+local res, res2 = 27
+
+a, b = 1, 2+3
+assert(a==1 and b==5)
+a={}
+function f() return 10, 11, 12 end
+a.x, b, a[1] = 1, 2, f()
+assert(a.x==1 and b==2 and a[1]==10)
+a[f()], b, a[f()+3] = f(), a, 'x'
+assert(a[10] == 10 and b == a and a[13] == 'x')
+
+do
+  local f = function (n) local x = {}; for i=1,n do x[i]=i end;
+                         return table.unpack(x) end;
+  local a,b,c
+  a,b = 0, f(1)
+  assert(a == 0 and b == 1)
+  A,b = 0, f(1)
+  assert(A == 0 and b == 1)
+  a,b,c = 0,5,f(4)
+  assert(a==0 and b==5 and c==1)
+  a,b,c = 0,5,f(0)
+  assert(a==0 and b==5 and c==nil)
+end
+
+a, b, c, d = 1 and nil, 1 or nil, (1 and (nil or 1)), 6
+assert(not a and b and c and d==6)
+
+d = 20
+a, b, c, d = f()
+assert(a==10 and b==11 and c==12 and d==nil)
+a,b = f(), 1, 2, 3, f()
+assert(a==10 and b==1)
+
+assert(a<b == false and a>b == true)
+assert((10 and 2) == 2)
+assert((10 or 2) == 10)
+assert((10 or assert(nil)) == 10)
+assert(not (nil and assert(nil)))
+assert((nil or "alo") == "alo")
+assert((nil and 10) == nil)
+assert((false and 10) == false)
+assert((true or 10) == true)
+assert((false or 10) == 10)
+assert(false ~= nil)
+assert(nil ~= false)
+assert(not nil == true)
+assert(not not nil == false)
+assert(not not 1 == true)
+assert(not not a == true)
+assert(not not (6 or nil) == true)
+assert(not not (nil and 56) == false)
+assert(not not (nil and true) == false)
+assert(not 10 == false)
+assert(not {} == false)
+assert(not 0.5 == false)
+assert(not "x" == false)
+
+assert({} ~= {})
+print('+')
+
+a = {}
+a[true] = 20
+a[false] = 10
+assert(a[1<2] == 20 and a[1>2] == 10)
+
+function f(a) return a end
+
+local a = {}
+for i=3000,-3000,-1 do a[i + 0.0] = i; end
+a[10e30] = "alo"; a[true] = 10; a[false] = 20
+assert(a[10e30] == 'alo' and a[not 1] == 20 and a[10<20] == 10)
+for i=3000,-3000,-1 do assert(a[i] == i); end
+a[print] = assert
+a[f] = print
+a[a] = a
+assert(a[a][a][a][a][print] == assert)
+a[print](a[a[f]] == a[print])
+assert(not pcall(function () local a = {}; a[nil] = 10 end))
+assert(not pcall(function () local a = {[nil] = 10} end))
+assert(a[nil] == undef)
+a = nil
+
+a = {10,9,8,7,6,5,4,3,2; [-3]='a', [f]=print, a='a', b='ab'}
+a, a.x, a.y = a, a[-3]
+assert(a[1]==10 and a[-3]==a.a and a[f]==print and a.x=='a' and not a.y)
+a[1], f(a)[2], b, c = {['alo']=assert}, 10, a[1], a[f], 6, 10, 23, f(a), 2
+a[1].alo(a[2]==10 and b==10 and c==print)
+
+a.aVeryLongName012345678901234567890123456789012345678901234567890123456789 = 10
+local function foo ()
+  return a.aVeryLongName012345678901234567890123456789012345678901234567890123456789
+end
+assert(foo() == 10 and
+a.aVeryLongName012345678901234567890123456789012345678901234567890123456789 ==
+10)
+
+
+
+-- test of large float/integer indices 
+
+-- compute maximum integer where all bits fit in a float
+local maxint = math.maxinteger
+
+-- trim (if needed) to fit in a float
+while maxint ~= (maxint + 0.0) or (maxint - 1) ~= (maxint - 1.0) do
+  maxint = maxint // 2
+end
+
+maxintF = maxint + 0.0   -- float version
+
+assert(maxintF == maxint and math.type(maxintF) == "float" and
+       maxintF >= 2.0^14)
+
+-- floats and integers must index the same places
+a[maxintF] = 10; a[maxintF - 1.0] = 11;
+a[-maxintF] = 12; a[-maxintF + 1.0] = 13;
+
+assert(a[maxint] == 10 and a[maxint - 1] == 11 and
+       a[-maxint] == 12 and a[-maxint + 1] == 13)
+
+a[maxint] = 20
+a[-maxint] = 22
+
+assert(a[maxintF] == 20 and a[maxintF - 1.0] == 11 and
+       a[-maxintF] == 22 and a[-maxintF + 1.0] == 13)
+
+a = nil
+
+
+-- test conflicts in multiple assignment
+do
+  local a,i,j,b
+  a = {'a', 'b'}; i=1; j=2; b=a
+  i, a[i], a, j, a[j], a[i+j] = j, i, i, b, j, i
+  assert(i == 2 and b[1] == 1 and a == 1 and j == b and b[2] == 2 and
+         b[3] == 1)
+  a = {}
+  local function foo ()    -- assigining to upvalues
+    b, a.x, a = a, 10, 20
+  end
+  foo()
+  assert(a == 20 and b.x == 10)
+end
+
+-- repeat test with upvalues
+do
+  local a,i,j,b
+  a = {'a', 'b'}; i=1; j=2; b=a
+  local function foo ()
+    i, a[i], a, j, a[j], a[i+j] = j, i, i, b, j, i
+  end
+  foo()
+  assert(i == 2 and b[1] == 1 and a == 1 and j == b and b[2] == 2 and
+         b[3] == 1)
+  local t = {}
+  (function (a) t[a], a = 10, 20  end)(1);
+  assert(t[1] == 10)
+end
+
+-- bug in 5.2 beta
+local function foo ()
+  local a
+  return function ()
+    local b
+    a, b = 3, 14    -- local and upvalue have same index
+    return a, b
+  end
+end
+
+local a, b = foo()()
+assert(a == 3 and b == 14)
+
+print('OK')
+
+return res
+
diff --git a/test/external/lua-5.4.0-tests/big.lua b/test/external/lua-5.4.0-tests/big.lua
new file mode 100644
index 0000000..39e293e
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/big.lua
@@ -0,0 +1,82 @@
+-- $Id: testes/big.lua $
+-- See Copyright Notice in file all.lua
+
+if _soft then
+  return 'a'
+end
+
+print "testing large tables"
+
+local debug = require"debug" 
+
+local lim = 2^18 + 1000
+local prog = { "local y = {0" }
+for i = 1, lim do prog[#prog + 1] = i  end
+prog[#prog + 1] = "}\n"
+prog[#prog + 1] = "X = y\n"
+prog[#prog + 1] = ("assert(X[%d] == %d)"):format(lim - 1, lim - 2)
+prog[#prog + 1] = "return 0"
+prog = table.concat(prog, ";")
+
+local env = {string = string, assert = assert}
+local f = assert(load(prog, nil, nil, env))
+
+f()
+assert(env.X[lim] == lim - 1 and env.X[lim + 1] == lim)
+for k in pairs(env) do env[k] = undef end
+
+-- yields during accesses larger than K (in RK)
+setmetatable(env, {
+  __index = function (t, n) coroutine.yield('g'); return _G[n] end,
+  __newindex = function (t, n, v) coroutine.yield('s'); _G[n] = v end,
+})
+
+X = nil
+co = coroutine.wrap(f)
+assert(co() == 's')
+assert(co() == 'g')
+assert(co() == 'g')
+assert(co() == 0)
+
+assert(X[lim] == lim - 1 and X[lim + 1] == lim)
+
+-- errors in accesses larger than K (in RK)
+getmetatable(env).__index = function () end
+getmetatable(env).__newindex = function () end
+local e, m = pcall(f)
+assert(not e and m:find("global 'X'"))
+
+-- errors in metamethods 
+getmetatable(env).__newindex = function () error("hi") end
+local e, m = xpcall(f, debug.traceback)
+assert(not e and m:find("'newindex'"))
+
+f, X = nil
+
+coroutine.yield'b'
+
+if 2^32 == 0 then   -- (small integers) {   
+
+print "testing string length overflow"
+
+local repstrings = 192          -- number of strings to be concatenated
+local ssize = math.ceil(2.0^32 / repstrings) + 1   -- size of each string
+
+assert(repstrings * ssize > 2.0^32)  -- it should be larger than maximum size
+
+local longs = string.rep("\0", ssize)   -- create one long string
+
+-- create function to concatenate 'repstrings' copies of its argument
+local rep = assert(load(
+  "local a = ...; return " .. string.rep("a", repstrings, "..")))
+
+local a, b = pcall(rep, longs)   -- call that function
+
+-- it should fail without creating string (result would be too large)
+assert(not a and string.find(b, "overflow"))
+
+end   -- }
+
+print'OK'
+
+return 'a'
diff --git a/test/external/lua-5.4.0-tests/bitwise.lua b/test/external/lua-5.4.0-tests/bitwise.lua
new file mode 100644
index 0000000..59781f5
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/bitwise.lua
@@ -0,0 +1,346 @@
+-- $Id: testes/bitwise.lua $
+-- See Copyright Notice in file all.lua
+
+print("testing bitwise operations")
+
+require "bwcoercion"
+
+local numbits = string.packsize('j') * 8
+
+assert(~0 == -1)
+
+assert((1 << (numbits - 1)) == math.mininteger)
+
+-- basic tests for bitwise operators;
+-- use variables to avoid constant folding
+local a, b, c, d
+a = 0xFFFFFFFFFFFFFFFF
+assert(a == -1 and a & -1 == a and a & 35 == 35)
+a = 0xF0F0F0F0F0F0F0F0
+assert(a | -1 == -1)
+assert(a ~ a == 0 and a ~ 0 == a and a ~ ~a == -1)
+assert(a >> 4 == ~a)
+a = 0xF0; b = 0xCC; c = 0xAA; d = 0xFD
+assert(a | b ~ c & d == 0xF4)
+
+a = 0xF0.0; b = 0xCC.0; c = "0xAA.0"; d = "0xFD.0"
+assert(a | b ~ c & d == 0xF4)
+
+a = 0xF0000000; b = 0xCC000000;
+c = 0xAA000000; d = 0xFD000000
+assert(a | b ~ c & d == 0xF4000000)
+assert(~~a == a and ~a == -1 ~ a and -d == ~d + 1)
+
+a = a << 32
+b = b << 32
+c = c << 32
+d = d << 32
+assert(a | b ~ c & d == 0xF4000000 << 32)
+assert(~~a == a and ~a == -1 ~ a and -d == ~d + 1)
+
+assert(-1 >> 1 == (1 << (numbits - 1)) - 1 and 1 << 31 == 0x80000000)
+assert(-1 >> (numbits - 1) == 1)
+assert(-1 >> numbits == 0 and
+       -1 >> -numbits == 0 and
+       -1 << numbits == 0 and
+       -1 << -numbits == 0)
+
+assert((2^30 - 1) << 2^30 == 0)
+assert((2^30 - 1) >> 2^30 == 0)
+
+assert(1 >> -3 == 1 << 3 and 1000 >> 5 == 1000 << -5)
+
+
+-- coercion from strings to integers
+assert("0xffffffffffffffff" | 0 == -1)
+assert("0xfffffffffffffffe" & "-1" == -2)
+assert(" \t-0xfffffffffffffffe\n\t" & "-1" == 2)
+assert("   \n  -45  \t " >> "  -2  " == -45 * 4)
+assert("1234.0" << "5.0" == 1234 * 32)
+assert("0xffff.0" ~ "0xAAAA" == 0x5555)
+assert(~"0x0.000p4" == -1)
+
+assert(("7" .. 3) << 1 == 146)
+assert(0xffffffff >> (1 .. "9") == 0x1fff)
+assert(10 | (1 .. "9") == 27)
+
+do
+  local st, msg = pcall(function () return 4 & "a" end)
+  assert(string.find(msg, "'band'"))
+
+  local st, msg = pcall(function () return ~"a" end)
+  assert(string.find(msg, "'bnot'"))
+end
+
+
+-- out of range number
+assert(not pcall(function () return "0xffffffffffffffff.0" | 0 end))
+
+-- embedded zeros
+assert(not pcall(function () return "0xffffffffffffffff\0" | 0 end))
+
+print'+'
+
+
+package.preload.bit32 = function ()     --{
+
+-- no built-in 'bit32' library: implement it using bitwise operators
+
+local bit = {}
+
+function bit.bnot (a)
+  return ~a & 0xFFFFFFFF
+end
+
+
+--
+-- in all vararg functions, avoid creating 'arg' table when there are
+-- only 2 (or less) parameters, as 2 parameters is the common case
+--
+
+function bit.band (x, y, z, ...)
+  if not z then
+    return ((x or -1) & (y or -1)) & 0xFFFFFFFF
+  else
+    local arg = {...}
+    local res = x & y & z
+    for i = 1, #arg do res = res & arg[i] end
+    return res & 0xFFFFFFFF
+  end
+end
+
+function bit.bor (x, y, z, ...)
+  if not z then
+    return ((x or 0) | (y or 0)) & 0xFFFFFFFF
+  else
+    local arg = {...}
+    local res = x | y | z
+    for i = 1, #arg do res = res | arg[i] end
+    return res & 0xFFFFFFFF
+  end
+end
+
+function bit.bxor (x, y, z, ...)
+  if not z then
+    return ((x or 0) ~ (y or 0)) & 0xFFFFFFFF
+  else
+    local arg = {...}
+    local res = x ~ y ~ z
+    for i = 1, #arg do res = res ~ arg[i] end
+    return res & 0xFFFFFFFF
+  end
+end
+
+function bit.btest (...)
+  return bit.band(...) ~= 0
+end
+
+function bit.lshift (a, b)
+  return ((a & 0xFFFFFFFF) << b) & 0xFFFFFFFF
+end
+
+function bit.rshift (a, b)
+  return ((a & 0xFFFFFFFF) >> b) & 0xFFFFFFFF
+end
+
+function bit.arshift (a, b)
+  a = a & 0xFFFFFFFF
+  if b <= 0 or (a & 0x80000000) == 0 then
+    return (a >> b) & 0xFFFFFFFF
+  else
+    return ((a >> b) | ~(0xFFFFFFFF >> b)) & 0xFFFFFFFF
+  end
+end
+
+function bit.lrotate (a ,b)
+  b = b & 31
+  a = a & 0xFFFFFFFF
+  a = (a << b) | (a >> (32 - b))
+  return a & 0xFFFFFFFF
+end
+
+function bit.rrotate (a, b)
+  return bit.lrotate(a, -b)
+end
+
+local function checkfield (f, w)
+  w = w or 1
+  assert(f >= 0, "field cannot be negative")
+  assert(w > 0, "width must be positive")
+  assert(f + w <= 32, "trying to access non-existent bits")
+  return f, ~(-1 << w)
+end
+
+function bit.extract (a, f, w)
+  local f, mask = checkfield(f, w)
+  return (a >> f) & mask
+end
+
+function bit.replace (a, v, f, w)
+  local f, mask = checkfield(f, w)
+  v = v & mask
+  a = (a & ~(mask << f)) | (v << f)
+  return a & 0xFFFFFFFF
+end
+
+return bit
+
+end  --}
+
+
+print("testing bitwise library")
+
+local bit32 = require'bit32'
+
+assert(bit32.band() == bit32.bnot(0))
+assert(bit32.btest() == true)
+assert(bit32.bor() == 0)
+assert(bit32.bxor() == 0)
+
+assert(bit32.band() == bit32.band(0xffffffff))
+assert(bit32.band(1,2) == 0)
+
+
+-- out-of-range numbers
+assert(bit32.band(-1) == 0xffffffff)
+assert(bit32.band((1 << 33) - 1) == 0xffffffff)
+assert(bit32.band(-(1 << 33) - 1) == 0xffffffff)
+assert(bit32.band((1 << 33) + 1) == 1)
+assert(bit32.band(-(1 << 33) + 1) == 1)
+assert(bit32.band(-(1 << 40)) == 0)
+assert(bit32.band(1 << 40) == 0)
+assert(bit32.band(-(1 << 40) - 2) == 0xfffffffe)
+assert(bit32.band((1 << 40) - 4) == 0xfffffffc)
+
+assert(bit32.lrotate(0, -1) == 0)
+assert(bit32.lrotate(0, 7) == 0)
+assert(bit32.lrotate(0x12345678, 0) == 0x12345678)
+assert(bit32.lrotate(0x12345678, 32) == 0x12345678)
+assert(bit32.lrotate(0x12345678, 4) == 0x23456781)
+assert(bit32.rrotate(0x12345678, -4) == 0x23456781)
+assert(bit32.lrotate(0x12345678, -8) == 0x78123456)
+assert(bit32.rrotate(0x12345678, 8) == 0x78123456)
+assert(bit32.lrotate(0xaaaaaaaa, 2) == 0xaaaaaaaa)
+assert(bit32.lrotate(0xaaaaaaaa, -2) == 0xaaaaaaaa)
+for i = -50, 50 do
+  assert(bit32.lrotate(0x89abcdef, i) == bit32.lrotate(0x89abcdef, i%32))
+end
+
+assert(bit32.lshift(0x12345678, 4) == 0x23456780)
+assert(bit32.lshift(0x12345678, 8) == 0x34567800)
+assert(bit32.lshift(0x12345678, -4) == 0x01234567)
+assert(bit32.lshift(0x12345678, -8) == 0x00123456)
+assert(bit32.lshift(0x12345678, 32) == 0)
+assert(bit32.lshift(0x12345678, -32) == 0)
+assert(bit32.rshift(0x12345678, 4) == 0x01234567)
+assert(bit32.rshift(0x12345678, 8) == 0x00123456)
+assert(bit32.rshift(0x12345678, 32) == 0)
+assert(bit32.rshift(0x12345678, -32) == 0)
+assert(bit32.arshift(0x12345678, 0) == 0x12345678)
+assert(bit32.arshift(0x12345678, 1) == 0x12345678 // 2)
+assert(bit32.arshift(0x12345678, -1) == 0x12345678 * 2)
+assert(bit32.arshift(-1, 1) == 0xffffffff)
+assert(bit32.arshift(-1, 24) == 0xffffffff)
+assert(bit32.arshift(-1, 32) == 0xffffffff)
+assert(bit32.arshift(-1, -1) == bit32.band(-1 * 2, 0xffffffff))
+
+assert(0x12345678 << 4 == 0x123456780)
+assert(0x12345678 << 8 == 0x1234567800)
+assert(0x12345678 << -4 == 0x01234567)
+assert(0x12345678 << -8 == 0x00123456)
+assert(0x12345678 << 32 == 0x1234567800000000)
+assert(0x12345678 << -32 == 0)
+assert(0x12345678 >> 4 == 0x01234567)
+assert(0x12345678 >> 8 == 0x00123456)
+assert(0x12345678 >> 32 == 0)
+assert(0x12345678 >> -32 == 0x1234567800000000)
+
+print("+")
+-- some special cases
+local c = {0, 1, 2, 3, 10, 0x80000000, 0xaaaaaaaa, 0x55555555,
+           0xffffffff, 0x7fffffff}
+
+for _, b in pairs(c) do
+  assert(bit32.band(b) == b)
+  assert(bit32.band(b, b) == b)
+  assert(bit32.band(b, b, b, b) == b)
+  assert(bit32.btest(b, b) == (b ~= 0))
+  assert(bit32.band(b, b, b) == b)
+  assert(bit32.band(b, b, b, ~b) == 0)
+  assert(bit32.btest(b, b, b) == (b ~= 0))
+  assert(bit32.band(b, bit32.bnot(b)) == 0)
+  assert(bit32.bor(b, bit32.bnot(b)) == bit32.bnot(0))
+  assert(bit32.bor(b) == b)
+  assert(bit32.bor(b, b) == b)
+  assert(bit32.bor(b, b, b) == b)
+  assert(bit32.bor(b, b, 0, ~b) == 0xffffffff)
+  assert(bit32.bxor(b) == b)
+  assert(bit32.bxor(b, b) == 0)
+  assert(bit32.bxor(b, b, b) == b)
+  assert(bit32.bxor(b, b, b, b) == 0)
+  assert(bit32.bxor(b, 0) == b)
+  assert(bit32.bnot(b) ~= b)
+  assert(bit32.bnot(bit32.bnot(b)) == b)
+  assert(bit32.bnot(b) == (1 << 32) - 1 - b)
+  assert(bit32.lrotate(b, 32) == b)
+  assert(bit32.rrotate(b, 32) == b)
+  assert(bit32.lshift(bit32.lshift(b, -4), 4) == bit32.band(b, bit32.bnot(0xf)))
+  assert(bit32.rshift(bit32.rshift(b, 4), -4) == bit32.band(b, bit32.bnot(0xf)))
+end
+
+-- for this test, use at most 24 bits (mantissa of a single float)
+c = {0, 1, 2, 3, 10, 0x800000, 0xaaaaaa, 0x555555, 0xffffff, 0x7fffff}
+for _, b in pairs(c) do
+  for i = -40, 40 do
+    local x = bit32.lshift(b, i)
+    local y = math.floor(math.fmod(b * 2.0^i, 2.0^32))
+    assert(math.fmod(x - y, 2.0^32) == 0)
+  end
+end
+
+assert(not pcall(bit32.band, {}))
+assert(not pcall(bit32.bnot, "a"))
+assert(not pcall(bit32.lshift, 45))
+assert(not pcall(bit32.lshift, 45, print))
+assert(not pcall(bit32.rshift, 45, print))
+
+print("+")
+
+
+-- testing extract/replace
+
+assert(bit32.extract(0x12345678, 0, 4) == 8)
+assert(bit32.extract(0x12345678, 4, 4) == 7)
+assert(bit32.extract(0xa0001111, 28, 4) == 0xa)
+assert(bit32.extract(0xa0001111, 31, 1) == 1)
+assert(bit32.extract(0x50000111, 31, 1) == 0)
+assert(bit32.extract(0xf2345679, 0, 32) == 0xf2345679)
+
+assert(not pcall(bit32.extract, 0, -1))
+assert(not pcall(bit32.extract, 0, 32))
+assert(not pcall(bit32.extract, 0, 0, 33))
+assert(not pcall(bit32.extract, 0, 31, 2))
+
+assert(bit32.replace(0x12345678, 5, 28, 4) == 0x52345678)
+assert(bit32.replace(0x12345678, 0x87654321, 0, 32) == 0x87654321)
+assert(bit32.replace(0, 1, 2) == 2^2)
+assert(bit32.replace(0, -1, 4) == 2^4)
+assert(bit32.replace(-1, 0, 31) == (1 << 31) - 1)
+assert(bit32.replace(-1, 0, 1, 2) == (1 << 32) - 7)
+
+
+-- testing conversion of floats
+
+assert(bit32.bor(3.0) == 3)
+assert(bit32.bor(-4.0) == 0xfffffffc)
+
+-- large floats and large-enough integers?
+if 2.0^50 < 2.0^50 + 1.0 and 2.0^50 < (-1 >> 1) then
+  assert(bit32.bor(2.0^32 - 5.0) == 0xfffffffb)
+  assert(bit32.bor(-2.0^32 - 6.0) == 0xfffffffa)
+  assert(bit32.bor(2.0^48 - 5.0) == 0xfffffffb)
+  assert(bit32.bor(-2.0^48 - 6.0) == 0xfffffffa)
+end
+
+print'OK'
+
diff --git a/test/external/lua-5.4.0-tests/bwcoercion.lua b/test/external/lua-5.4.0-tests/bwcoercion.lua
new file mode 100644
index 0000000..cd735ab
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/bwcoercion.lua
@@ -0,0 +1,78 @@
+local tonumber, tointeger = tonumber, math.tointeger
+local type, getmetatable, rawget, error = type, getmetatable, rawget, error
+local strsub = string.sub
+
+local print = print
+
+_ENV = nil
+
+-- Try to convert a value to an integer, without assuming any coercion.
+local function toint (x)
+  x = tonumber(x)   -- handle numerical strings
+  if not x then
+    return false    -- not coercible to a number
+  end
+  return tointeger(x)
+end
+
+
+-- If operation fails, maybe second operand has a metamethod that should
+-- have been called if not for this string metamethod, so try to
+-- call it.
+local function trymt (x, y, mtname)
+  if type(y) ~= "string" then    -- avoid recalling original metamethod
+    local mt = getmetatable(y)
+    local mm = mt and rawget(mt, mtname)
+    if mm then
+      return mm(x, y)
+    end
+  end
+  -- if any test fails, there is no other metamethod to be called
+  error("attempt to '" .. strsub(mtname, 3) ..
+        "' a " .. type(x) .. " with a " .. type(y), 4)
+end
+
+
+local function checkargs (x, y, mtname)
+  local xi = toint(x)
+  local yi = toint(y)
+  if xi and yi then
+    return xi, yi
+  else
+    return trymt(x, y, mtname), nil
+  end
+end
+
+
+local smt = getmetatable("")
+
+smt.__band = function (x, y)
+  local x, y = checkargs(x, y, "__band")
+  return y and x & y or x
+end
+
+smt.__bor = function (x, y)
+  local x, y = checkargs(x, y, "__bor")
+  return y and x | y or x
+end
+
+smt.__bxor = function (x, y)
+  local x, y = checkargs(x, y, "__bxor")
+  return y and x ~ y or x
+end
+
+smt.__shl = function (x, y)
+  local x, y = checkargs(x, y, "__shl")
+  return y and x << y or x
+end
+
+smt.__shr = function (x, y)
+  local x, y = checkargs(x, y, "__shr")
+  return y and x >> y or x
+end
+
+smt.__bnot = function (x)
+  local x, y = checkargs(x, x, "__bnot")
+  return y and ~x or x
+end
+
diff --git a/test/external/lua-5.4.0-tests/calls.lua b/test/external/lua-5.4.0-tests/calls.lua
new file mode 100644
index 0000000..1701f15
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/calls.lua
@@ -0,0 +1,458 @@
+-- $Id: testes/calls.lua $
+-- See Copyright Notice in file all.lua
+
+print("testing functions and calls")
+
+local debug = require "debug"
+
+-- get the opportunity to test 'type' too ;)
+
+assert(type(1<2) == 'boolean')
+assert(type(true) == 'boolean' and type(false) == 'boolean')
+assert(type(nil) == 'nil'
+   and type(-3) == 'number'
+   and type'x' == 'string'
+   and type{} == 'table'
+   and type(type) == 'function')
+
+assert(type(assert) == type(print))
+function f (x) return a:x (x) end
+assert(type(f) == 'function')
+assert(not pcall(type))
+
+
+-- testing local-function recursion
+fact = false
+do
+  local res = 1
+  local function fact (n)
+    if n==0 then return res
+    else return n*fact(n-1)
+    end
+  end
+  assert(fact(5) == 120)
+end
+assert(fact == false)
+
+-- testing declarations
+a = {i = 10}
+self = 20
+function a:x (x) return x+self.i end
+function a.y (x) return x+self end
+
+assert(a:x(1)+10 == a.y(1))
+
+a.t = {i=-100}
+a["t"].x = function (self, a,b) return self.i+a+b end
+
+assert(a.t:x(2,3) == -95)
+
+do
+  local a = {x=0}
+  function a:add (x) self.x, a.y = self.x+x, 20; return self end
+  assert(a:add(10):add(20):add(30).x == 60 and a.y == 20)
+end
+
+local a = {b={c={}}}
+
+function a.b.c.f1 (x) return x+1 end
+function a.b.c:f2 (x,y) self[x] = y end
+assert(a.b.c.f1(4) == 5)
+a.b.c:f2('k', 12); assert(a.b.c.k == 12)
+
+print('+')
+
+t = nil   -- 'declare' t
+function f(a,b,c) local d = 'a'; t={a,b,c,d} end
+
+f(      -- this line change must be valid
+  1,2)
+assert(t[1] == 1 and t[2] == 2 and t[3] == nil and t[4] == 'a')
+f(1,2,   -- this one too
+      3,4)
+assert(t[1] == 1 and t[2] == 2 and t[3] == 3 and t[4] == 'a')
+
+function fat(x)
+  if x <= 1 then return 1
+  else return x*load("return fat(" .. x-1 .. ")", "")()
+  end
+end
+
+assert(load "load 'assert(fat(6)==720)' () ")()
+a = load('return fat(5), 3')
+a,b = a()
+assert(a == 120 and b == 3)
+print('+')
+
+function err_on_n (n)
+  if n==0 then error(); exit(1);
+  else err_on_n (n-1); exit(1);
+  end
+end
+
+do
+  function dummy (n)
+    if n > 0 then
+      assert(not pcall(err_on_n, n))
+      dummy(n-1)
+    end
+  end
+end
+
+dummy(10)
+
+function deep (n)
+  if n>0 then deep(n-1) end
+end
+deep(10)
+deep(180)
+
+
+print"testing tail calls"
+
+function deep (n) if n>0 then return deep(n-1) else return 101 end end
+assert(deep(30000) == 101)
+a = {}
+function a:deep (n) if n>0 then return self:deep(n-1) else return 101 end end
+assert(a:deep(30000) == 101)
+
+do   -- tail calls x varargs
+  local function foo (x, ...) local a = {...}; return x, a[1], a[2] end
+
+  local function foo1 (x) return foo(10, x, x + 1) end
+
+  local a, b, c = foo1(-2)
+  assert(a == 10 and b == -2 and c == -1)
+
+  -- tail calls x metamethods
+  local t = setmetatable({}, {__call = foo})
+  local function foo2 (x) return t(10, x) end
+  a, b, c = foo2(100)
+  assert(a == t and b == 10 and c == 100)
+
+  a, b = (function () return foo() end)()
+  assert(a == nil and b == nil)
+
+  local X, Y, A
+  local function foo (x, y, ...) X = x; Y = y; A = {...} end
+  local function foo1 (...) return foo(...) end
+
+  local a, b, c = foo1()
+  assert(X == nil and Y == nil and #A == 0)
+
+  a, b, c = foo1(10)
+  assert(X == 10 and Y == nil and #A == 0)
+
+  a, b, c = foo1(10, 20)
+  assert(X == 10 and Y == 20 and #A == 0)
+
+  a, b, c = foo1(10, 20, 30)
+  assert(X == 10 and Y == 20 and #A == 1 and A[1] == 30)
+end
+
+
+
+do   -- tail calls x chain of __call
+  local n = 10000   -- depth
+
+  local function foo ()
+    if n == 0 then return 1023
+    else n = n - 1; return foo()
+    end
+  end
+
+  -- build a chain of __call metamethods ending in function 'foo'
+  for i = 1, 100 do
+    foo = setmetatable({}, {__call = foo})
+  end
+
+  -- call the first one as a tail call in a new coroutine
+  -- (to ensure stack is not preallocated)
+  assert(coroutine.wrap(function() return foo() end)() == 1023)
+end
+
+print('+')
+
+
+do  -- testing chains of '__call'
+  local N = 20
+  local u = table.pack
+  for i = 1, N do
+    u = setmetatable({i}, {__call = u})
+  end
+
+  local Res = u("a", "b", "c")
+
+  assert(Res.n == N + 3)
+  for i = 1, N do
+    assert(Res[i][1] == i)
+  end
+  assert(Res[N + 1] == "a" and Res[N + 2] == "b" and Res[N + 3] == "c")
+end
+
+
+a = nil
+(function (x) a=x end)(23)
+assert(a == 23 and (function (x) return x*2 end)(20) == 40)
+
+
+-- testing closures
+
+-- fixed-point operator
+Z = function (le)
+      local function a (f)
+        return le(function (x) return f(f)(x) end)
+      end
+      return a(a)
+    end
+
+
+-- non-recursive factorial
+
+F = function (f)
+      return function (n)
+               if n == 0 then return 1
+               else return n*f(n-1) end
+             end
+    end
+
+fat = Z(F)
+
+assert(fat(0) == 1 and fat(4) == 24 and Z(F)(5)==5*Z(F)(4))
+
+local function g (z)
+  local function f (a,b,c,d)
+    return function (x,y) return a+b+c+d+a+x+y+z end
+  end
+  return f(z,z+1,z+2,z+3)
+end
+
+f = g(10)
+assert(f(9, 16) == 10+11+12+13+10+9+16+10)
+
+Z, F, f = nil
+print('+')
+
+-- testing multiple returns
+
+function unlpack (t, i)
+  i = i or 1
+  if (i <= #t) then
+    return t[i], unlpack(t, i+1)
+  end
+end
+
+function equaltab (t1, t2)
+  assert(#t1 == #t2)
+  for i = 1, #t1 do
+    assert(t1[i] == t2[i])
+  end
+end
+
+local pack = function (...) return (table.pack(...)) end
+
+function f() return 1,2,30,4 end
+function ret2 (a,b) return a,b end
+
+local a,b,c,d = unlpack{1,2,3}
+assert(a==1 and b==2 and c==3 and d==nil)
+a = {1,2,3,4,false,10,'alo',false,assert}
+equaltab(pack(unlpack(a)), a)
+equaltab(pack(unlpack(a), -1), {1,-1})
+a,b,c,d = ret2(f()), ret2(f())
+assert(a==1 and b==1 and c==2 and d==nil)
+a,b,c,d = unlpack(pack(ret2(f()), ret2(f())))
+assert(a==1 and b==1 and c==2 and d==nil)
+a,b,c,d = unlpack(pack(ret2(f()), (ret2(f()))))
+assert(a==1 and b==1 and c==nil and d==nil)
+
+a = ret2{ unlpack{1,2,3}, unlpack{3,2,1}, unlpack{"a", "b"}}
+assert(a[1] == 1 and a[2] == 3 and a[3] == "a" and a[4] == "b")
+
+
+-- testing calls with 'incorrect' arguments
+rawget({}, "x", 1)
+rawset({}, "x", 1, 2)
+assert(math.sin(1,2) == math.sin(1))
+table.sort({10,9,8,4,19,23,0,0}, function (a,b) return a<b end, "extra arg")
+
+
+-- test for generic load
+local x = "-- a comment\0\0\0\n  x = 10 + \n23; \
+     local a = function () x = 'hi' end; \
+     return '\0'"
+function read1 (x)
+  local i = 0
+  return function ()
+    collectgarbage()
+    i=i+1
+    return string.sub(x, i, i)
+  end
+end
+
+function cannotload (msg, a,b)
+  assert(not a and string.find(b, msg))
+end
+
+a = assert(load(read1(x), "modname", "t", _G))
+assert(a() == "\0" and _G.x == 33)
+assert(debug.getinfo(a).source == "modname")
+-- cannot read text in binary mode
+cannotload("attempt to load a text chunk", load(read1(x), "modname", "b", {}))
+cannotload("attempt to load a text chunk", load(x, "modname", "b"))
+
+a = assert(load(function () return nil end))
+a()  -- empty chunk
+
+assert(not load(function () return true end))
+
+
+-- small bug
+local t = {nil, "return ", "3"}
+f, msg = load(function () return table.remove(t, 1) end)
+assert(f() == nil)   -- should read the empty chunk
+
+-- another small bug (in 5.2.1)
+f = load(string.dump(function () return 1 end), nil, "b", {})
+assert(type(f) == "function" and f() == 1)
+
+
+x = string.dump(load("x = 1; return x"))
+a = assert(load(read1(x), nil, "b"))
+assert(a() == 1 and _G.x == 1)
+cannotload("attempt to load a binary chunk", load(read1(x), nil, "t"))
+cannotload("attempt to load a binary chunk", load(x, nil, "t"))
+
+assert(not pcall(string.dump, print))  -- no dump of C functions
+
+cannotload("unexpected symbol", load(read1("*a = 123")))
+cannotload("unexpected symbol", load("*a = 123"))
+cannotload("hhi", load(function () error("hhi") end))
+
+-- any value is valid for _ENV
+assert(load("return _ENV", nil, nil, 123)() == 123)
+
+
+-- load when _ENV is not first upvalue
+local x; XX = 123
+local function h ()
+  local y=x   -- use 'x', so that it becomes 1st upvalue
+  return XX   -- global name
+end
+local d = string.dump(h)
+x = load(d, "", "b")
+assert(debug.getupvalue(x, 2) == '_ENV')
+debug.setupvalue(x, 2, _G)
+assert(x() == 123)
+
+assert(assert(load("return XX + ...", nil, nil, {XX = 13}))(4) == 17)
+
+
+-- test generic load with nested functions
+x = [[
+  return function (x)
+    return function (y)
+     return function (z)
+       return x+y+z
+     end
+   end
+  end
+]]
+
+a = assert(load(read1(x)))
+assert(a()(2)(3)(10) == 15)
+
+
+-- test for dump/undump with upvalues
+local a, b = 20, 30
+x = load(string.dump(function (x)
+  if x == "set" then a = 10+b; b = b+1 else
+  return a
+  end
+end), "", "b", nil)
+assert(x() == nil)
+assert(debug.setupvalue(x, 1, "hi") == "a")
+assert(x() == "hi")
+assert(debug.setupvalue(x, 2, 13) == "b")
+assert(not debug.setupvalue(x, 3, 10))   -- only 2 upvalues
+x("set")
+assert(x() == 23)
+x("set")
+assert(x() == 24)
+
+-- test for dump/undump with many upvalues
+do
+  local nup = 200    -- maximum number of local variables
+  local prog = {"local a1"}
+  for i = 2, nup do prog[#prog + 1] = ", a" .. i end
+  prog[#prog + 1] = " = 1"
+  for i = 2, nup do prog[#prog + 1] = ", " .. i end
+  local sum = 1
+  prog[#prog + 1] = "; return function () return a1"
+  for i = 2, nup do prog[#prog + 1] = " + a" .. i; sum = sum + i end
+  prog[#prog + 1] = " end"
+  prog = table.concat(prog)
+  local f = assert(load(prog))()
+  assert(f() == sum)
+
+  f = load(string.dump(f))   -- main chunk now has many upvalues
+  local a = 10
+  local h = function () return a end
+  for i = 1, nup do
+    debug.upvaluejoin(f, i, h, 1)
+  end
+  assert(f() == 10 * nup)
+end
+
+-- test for long method names
+do
+  local t = {x = 1}
+  function t:_012345678901234567890123456789012345678901234567890123456789 ()
+    return self.x
+  end
+  assert(t:_012345678901234567890123456789012345678901234567890123456789() == 1)
+end
+
+
+-- test for bug in parameter adjustment
+assert((function () return nil end)(4) == nil)
+assert((function () local a; return a end)(4) == nil)
+assert((function (a) return a end)() == nil)
+
+
+print("testing binary chunks")
+do
+  local header = string.pack("c4BBc6BBBj",
+    "\27Lua",                                  -- signature
+    0x54,                                      -- version 5.4 (0x54)
+    0,                                         -- format
+    "\x19\x93\r\n\x1a\n",                      -- data
+    4,                                         -- size of instruction
+    string.packsize("j"),                      -- sizeof(lua integer)
+    string.packsize("n"),                      -- sizeof(lua number)
+    0x5678                                     -- LUAC_INT
+    -- LUAC_NUM may not have a unique binary representation (padding...)
+  )
+  local c = string.dump(function () local a = 1; local b = 3; return a+b*3 end)
+
+  assert(string.sub(c, 1, #header) == header)
+
+  -- corrupted header
+  for i = 1, #header do
+    local s = string.sub(c, 1, i - 1) ..
+              string.char(string.byte(string.sub(c, i, i)) + 1) ..
+              string.sub(c, i + 1, -1)
+    assert(#s == #c)
+    assert(not load(s))
+  end
+
+  -- loading truncated binary chunks
+  for i = 1, #c - 1 do
+    local st, msg = load(string.sub(c, 1, i))
+    assert(not st and string.find(msg, "truncated"))
+  end
+  assert(assert(load(c))() == 10)
+end
+
+print('OK')
+return deep
diff --git a/test/external/lua-5.4.0-tests/closure.lua b/test/external/lua-5.4.0-tests/closure.lua
new file mode 100644
index 0000000..cdeaeba
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/closure.lua
@@ -0,0 +1,270 @@
+-- $Id: testes/closure.lua $
+-- See Copyright Notice in file all.lua
+
+print "testing closures"
+
+local A,B = 0,{g=10}
+function f(x)
+  local a = {}
+  for i=1,1000 do
+    local y = 0
+    do
+      a[i] = function () B.g = B.g+1; y = y+x; return y+A end
+    end
+  end
+  local dummy = function () return a[A] end
+  collectgarbage()
+  A = 1; assert(dummy() == a[1]); A = 0;
+  assert(a[1]() == x)
+  assert(a[3]() == x)
+  collectgarbage()
+  assert(B.g == 12)
+  return a
+end
+
+local a = f(10)
+-- force a GC in this level
+local x = {[1] = {}}   -- to detect a GC
+setmetatable(x, {__mode = 'kv'})
+while x[1] do   -- repeat until GC
+  local a = A..A..A..A  -- create garbage
+  A = A+1
+end
+assert(a[1]() == 20+A)
+assert(a[1]() == 30+A)
+assert(a[2]() == 10+A)
+collectgarbage()
+assert(a[2]() == 20+A)
+assert(a[2]() == 30+A)
+assert(a[3]() == 20+A)
+assert(a[8]() == 10+A)
+assert(getmetatable(x).__mode == 'kv')
+assert(B.g == 19)
+
+
+-- testing equality
+a = {}
+
+for i = 1, 5 do  a[i] = function (x) return i + a + _ENV end  end
+assert(a[3] ~= a[4] and a[4] ~= a[5])
+
+do
+  local a = function (x)  return math.sin(_ENV[x])  end
+  local function f()
+    return a
+  end
+  assert(f() == f())
+end
+
+
+-- testing closures with 'for' control variable
+a = {}
+for i=1,10 do
+  a[i] = {set = function(x) i=x end, get = function () return i end}
+  if i == 3 then break end
+end
+assert(a[4] == undef)
+a[1].set(10)
+assert(a[2].get() == 2)
+a[2].set('a')
+assert(a[3].get() == 3)
+assert(a[2].get() == 'a')
+
+a = {}
+local t = {"a", "b"}
+for i = 1, #t do
+  local k = t[i]
+  a[i] = {set = function(x, y) i=x; k=y end,
+          get = function () return i, k end}
+  if i == 2 then break end
+end
+a[1].set(10, 20)
+local r,s = a[2].get()
+assert(r == 2 and s == 'b')
+r,s = a[1].get()
+assert(r == 10 and s == 20)
+a[2].set('a', 'b')
+r,s = a[2].get()
+assert(r == "a" and s == "b")
+
+
+-- testing closures with 'for' control variable x break
+for i=1,3 do
+  f = function () return i end
+  break
+end
+assert(f() == 1)
+
+for k = 1, #t do
+  local v = t[k]
+  f = function () return k, v end
+  break
+end
+assert(({f()})[1] == 1)
+assert(({f()})[2] == "a")
+
+
+-- testing closure x break x return x errors
+
+local b
+function f(x)
+  local first = 1
+  while 1 do
+    if x == 3 and not first then return end
+    local a = 'xuxu'
+    b = function (op, y)
+          if op == 'set' then
+            a = x+y
+          else
+            return a
+          end
+        end
+    if x == 1 then do break end
+    elseif x == 2 then return
+    else if x ~= 3 then error() end
+    end
+    first = nil
+  end
+end
+
+for i=1,3 do
+  f(i)
+  assert(b('get') == 'xuxu')
+  b('set', 10); assert(b('get') == 10+i)
+  b = nil
+end
+
+pcall(f, 4);
+assert(b('get') == 'xuxu')
+b('set', 10); assert(b('get') == 14)
+
+
+local w
+-- testing multi-level closure
+function f(x)
+  return function (y)
+    return function (z) return w+x+y+z end
+  end
+end
+
+y = f(10)
+w = 1.345
+assert(y(20)(30) == 60+w)
+
+
+-- testing closures x break
+do
+  local X, Y
+  local a = math.sin(0)
+
+  while a do
+    local b = 10
+    X = function () return b end   -- closure with upvalue
+    if a then break end
+  end
+  
+  do
+    local b = 20
+    Y = function () return b end   -- closure with upvalue
+  end
+
+  -- upvalues must be different
+  assert(X() == 10 and Y() == 20)
+end
+
+  
+-- testing closures x repeat-until
+
+local a = {}
+local i = 1
+repeat
+  local x = i
+  a[i] = function () i = x+1; return x end
+until i > 10 or a[i]() ~= x
+assert(i == 11 and a[1]() == 1 and a[3]() == 3 and i == 4)
+
+
+-- testing closures created in 'then' and 'else' parts of 'if's
+a = {}
+for i = 1, 10 do
+  if i % 3 == 0 then
+    local y = 0
+    a[i] = function (x) local t = y; y = x; return t end
+  elseif i % 3 == 1 then
+    goto L1
+    error'not here'
+  ::L1::
+    local y = 1
+    a[i] = function (x) local t = y; y = x; return t end
+  elseif i % 3 == 2 then
+    local t
+    goto l4
+    ::l4a:: a[i] = t; goto l4b
+    error("should never be here!")
+    ::l4::
+    local y = 2
+    t = function (x) local t = y; y = x; return t end
+    goto l4a
+    error("should never be here!")
+    ::l4b::
+  end
+end
+
+for i = 1, 10 do
+  assert(a[i](i * 10) == i % 3 and a[i]() == i * 10)
+end
+
+print'+'
+
+
+-- test for correctly closing upvalues in tail calls of vararg functions
+local function t ()
+  local function c(a,b) assert(a=="test" and b=="OK") end
+  local function v(f, ...) c("test", f() ~= 1 and "FAILED" or "OK") end
+  local x = 1
+  return v(function() return x end)
+end
+t()
+
+
+-- test for debug manipulation of upvalues
+local debug = require'debug'
+
+do
+  local a , b, c = 3, 5, 7
+  foo1 = function () return a+b end;
+  foo2 = function () return b+a end;
+  do
+    local a = 10
+    foo3 = function () return a+b end;
+  end
+end
+
+assert(debug.upvalueid(foo1, 1))
+assert(debug.upvalueid(foo1, 2))
+assert(not pcall(debug.upvalueid, foo1, 3))
+assert(debug.upvalueid(foo1, 1) == debug.upvalueid(foo2, 2))
+assert(debug.upvalueid(foo1, 2) == debug.upvalueid(foo2, 1))
+assert(debug.upvalueid(foo3, 1))
+assert(debug.upvalueid(foo1, 1) ~= debug.upvalueid(foo3, 1))
+assert(debug.upvalueid(foo1, 2) == debug.upvalueid(foo3, 2))
+
+assert(debug.upvalueid(string.gmatch("x", "x"), 1) ~= nil)
+
+assert(foo1() == 3 + 5 and foo2() == 5 + 3)
+debug.upvaluejoin(foo1, 2, foo2, 2)
+assert(foo1() == 3 + 3 and foo2() == 5 + 3)
+assert(foo3() == 10 + 5)
+debug.upvaluejoin(foo3, 2, foo2, 1)
+assert(foo3() == 10 + 5)
+debug.upvaluejoin(foo3, 2, foo2, 2)
+assert(foo3() == 10 + 3)
+
+assert(not pcall(debug.upvaluejoin, foo1, 3, foo2, 1))
+assert(not pcall(debug.upvaluejoin, foo1, 1, foo2, 3))
+assert(not pcall(debug.upvaluejoin, foo1, 0, foo2, 1))
+assert(not pcall(debug.upvaluejoin, print, 1, foo2, 1))
+assert(not pcall(debug.upvaluejoin, {}, 1, foo2, 1))
+assert(not pcall(debug.upvaluejoin, foo1, 1, print, 1))
+
+print'OK'
diff --git a/test/external/lua-5.4.0-tests/code.lua b/test/external/lua-5.4.0-tests/code.lua
new file mode 100644
index 0000000..34b0466
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/code.lua
@@ -0,0 +1,443 @@
+-- $Id: testes/code.lua $
+-- See Copyright Notice in file all.lua
+
+if T==nil then
+  (Message or print)('\n >>> testC not active: skipping opcode tests <<<\n')
+  return
+end
+print "testing code generation and optimizations"
+
+-- to test constant propagation
+local k0aux <const> = 0
+local k0 <const> = k0aux
+local k1 <const> = 1
+local k3 <const> = 3
+local k6 <const> = k3 + (k3 << k0)
+local kFF0 <const> = 0xFF0
+local k3_78 <const> = 3.78
+local x, k3_78_4 <const> = 10, k3_78 / 4
+assert(x == 10)
+
+local kx <const> = "x"
+
+local kTrue <const> = true
+local kFalse <const> = false
+
+local kNil <const> = nil
+
+-- this code gave an error for the code checker
+do
+  local function f (a)
+  for k,v,w in a do end
+  end
+end
+
+
+-- testing reuse in constant table
+local function checkKlist (func, list)
+  local k = T.listk(func)
+  assert(#k == #list)
+  for i = 1, #k do
+    assert(k[i] == list[i] and math.type(k[i]) == math.type(list[i]))
+  end
+end
+
+local function foo ()
+  local a
+  a = k3;
+  a = 0; a = 0.0; a = -7 + 7
+  a = k3_78/4; a = k3_78_4
+  a = -k3_78/4; a = k3_78/4; a = -3.78/4
+  a = -3.79/4; a = 0.0; a = -0;
+  a = k3; a = 3.0; a = 3; a = 3.0
+end
+
+checkKlist(foo, {3.78/4, -3.78/4, -3.79/4})
+
+
+-- testing opcodes
+
+-- check that 'f' opcodes match '...'
+function check (f, ...)
+  local arg = {...}
+  local c = T.listcode(f)
+  for i=1, #arg do
+    local opcode = string.match(c[i], "%u%w+")
+    -- print(arg[i], opcode)
+    assert(arg[i] == opcode)
+  end
+  assert(c[#arg+2] == undef)
+end
+
+
+-- check that 'f' opcodes match '...' and that 'f(p) == r'.
+function checkR (f, p, r, ...)
+  local r1 = f(p)
+  assert(r == r1 and math.type(r) == math.type(r1))
+  check(f, ...)
+end
+
+
+-- check that 'a' and 'b' has the same opcodes
+function checkequal (a, b)
+  a = T.listcode(a)
+  b = T.listcode(b)
+  assert(#a == #b)
+  for i = 1, #a do
+    a[i] = string.gsub(a[i], '%b()', '')   -- remove line number
+    b[i] = string.gsub(b[i], '%b()', '')   -- remove line number
+    assert(a[i] == b[i])
+  end
+end
+
+
+-- some basic instructions
+check(function ()   -- function does not create upvalues
+  (function () end){f()}
+end, 'CLOSURE', 'NEWTABLE', 'EXTRAARG', 'GETTABUP', 'CALL',
+     'SETLIST', 'CALL', 'RETURN0')
+
+check(function (x)   -- function creates upvalues
+  (function () return x end){f()}
+end, 'CLOSURE', 'NEWTABLE', 'EXTRAARG', 'GETTABUP', 'CALL',
+     'SETLIST', 'CALL', 'RETURN')
+
+
+-- sequence of LOADNILs
+check(function ()
+  local kNil <const> = nil
+  local a,b,c
+  local d; local e;
+  local f,g,h;
+  d = nil; d=nil; b=nil; a=kNil; c=nil;
+end, 'LOADNIL', 'RETURN0')
+
+check(function ()
+  local a,b,c,d = 1,1,1,1
+  d=nil;c=nil;b=nil;a=nil
+end, 'LOADI', 'LOADI', 'LOADI', 'LOADI', 'LOADNIL', 'RETURN0')
+
+do
+  local a,b,c,d = 1,1,1,1
+  d=nil;c=nil;b=nil;a=nil
+  assert(a == nil and b == nil and c == nil and d == nil)
+end
+
+
+-- single return
+check (function (a,b,c) return a end, 'RETURN1')
+
+
+-- infinite loops
+check(function () while kTrue do local a = -1 end end,
+'LOADI', 'JMP', 'RETURN0')
+
+check(function () while 1 do local a = -1 end end,
+'LOADI', 'JMP', 'RETURN0')
+
+check(function () repeat local x = 1 until true end,
+'LOADI', 'RETURN0')
+
+
+-- concat optimization
+check(function (a,b,c,d) return a..b..c..d end,
+  'MOVE', 'MOVE', 'MOVE', 'MOVE', 'CONCAT', 'RETURN1')
+
+-- not
+check(function () return not not nil end, 'LOADFALSE', 'RETURN1')
+check(function () return not not kFalse end, 'LOADFALSE', 'RETURN1')
+check(function () return not not true end, 'LOADTRUE', 'RETURN1')
+check(function () return not not k3 end, 'LOADTRUE', 'RETURN1')
+
+-- direct access to locals
+check(function ()
+  local a,b,c,d
+  a = b*a
+  c.x, a[b] = -((a + d/b - a[b]) ^ a.x), b
+end,
+  'LOADNIL',
+  'MUL', 'MMBIN',
+  'DIV', 'MMBIN', 'ADD', 'MMBIN', 'GETTABLE', 'SUB', 'MMBIN',
+  'GETFIELD', 'POW', 'MMBIN', 'UNM', 'SETTABLE', 'SETFIELD', 'RETURN0')
+
+
+-- direct access to constants
+check(function ()
+  local a,b
+  local c = kNil
+  a[kx] = 3.2
+  a.x = b
+  a[b] = 'x'
+end,
+  'LOADNIL', 'SETFIELD', 'SETFIELD', 'SETTABLE', 'RETURN0')
+
+-- "get/set table" with numeric indices
+check(function (a)
+  local k255 <const> = 255
+  a[1] = a[100]
+  a[k255] = a[256]
+  a[256] = 5
+end,
+  'GETI', 'SETI',
+  'LOADI', 'GETTABLE', 'SETI',
+  'LOADI', 'SETTABLE',  'RETURN0')
+
+check(function ()
+  local a,b
+  a = a - a
+  b = a/a
+  b = 5-4
+end,
+  'LOADNIL', 'SUB', 'MMBIN', 'DIV', 'MMBIN', 'LOADI', 'RETURN0')
+
+check(function ()
+  local a,b
+  a[kTrue] = false
+end,
+  'LOADNIL', 'LOADTRUE', 'SETTABLE', 'RETURN0')
+
+
+-- equalities
+checkR(function (a) if a == 1 then return 2 end end, 1, 2,
+  'EQI', 'JMP', 'LOADI', 'RETURN1')
+
+checkR(function (a) if -4.0 == a then return 2 end end, -4, 2,
+  'EQI', 'JMP', 'LOADI', 'RETURN1')
+
+checkR(function (a) if a == "hi" then return 2 end end, 10, nil,
+  'EQK', 'JMP', 'LOADI', 'RETURN1')
+
+checkR(function (a) if a == 10000 then return 2 end end, 1, nil,
+  'EQK', 'JMP', 'LOADI', 'RETURN1')   -- number too large
+
+checkR(function (a) if -10000 == a then return 2 end end, -10000, 2,
+  'EQK', 'JMP', 'LOADI', 'RETURN1')   -- number too large
+
+-- comparisons
+
+checkR(function (a) if -10 <= a then return 2 end end, -10, 2,
+  'GEI', 'JMP', 'LOADI', 'RETURN1')
+
+checkR(function (a) if 128.0 > a then return 2 end end, 129, nil,
+  'LTI', 'JMP', 'LOADI', 'RETURN1')
+
+checkR(function (a) if -127.0 < a then return 2 end end, -127, nil,
+  'GTI', 'JMP', 'LOADI', 'RETURN1')
+
+checkR(function (a) if 10 < a then return 2 end end, 11, 2,
+  'GTI', 'JMP', 'LOADI', 'RETURN1')
+
+checkR(function (a) if 129 < a then return 2 end end, 130, 2,
+  'LOADI', 'LT', 'JMP', 'LOADI', 'RETURN1')
+
+checkR(function (a) if a >= 23.0 then return 2 end end, 25, 2,
+  'GEI', 'JMP', 'LOADI', 'RETURN1')
+
+checkR(function (a) if a >= 23.1 then return 2 end end, 0, nil,
+  'LOADK', 'LE', 'JMP', 'LOADI', 'RETURN1')
+
+checkR(function (a) if a > 2300.0 then return 2 end end, 0, nil,
+  'LOADF', 'LT', 'JMP', 'LOADI', 'RETURN1')
+
+
+-- constant folding
+local function checkK (func, val)
+  check(func, 'LOADK', 'RETURN1')
+  checkKlist(func, {val})
+  assert(func() == val)
+end
+
+local function checkI (func, val)
+  check(func, 'LOADI', 'RETURN1')
+  checkKlist(func, {})
+  assert(func() == val)
+end
+
+local function checkF (func, val)
+  check(func, 'LOADF', 'RETURN1')
+  checkKlist(func, {})
+  assert(func() == val)
+end
+
+checkF(function () return 0.0 end, 0.0)
+checkI(function () return k0 end, 0)
+checkI(function () return -k0//1 end, 0)
+checkK(function () return 3^-1 end, 1/3)
+checkK(function () return (1 + 1)^(50 + 50) end, 2^100)
+checkK(function () return (-2)^(31 - 2) end, -0x20000000 + 0.0)
+checkF(function () return (-k3^0 + 5) // 3.0 end, 1.0)
+checkI(function () return -k3 % 5 end, 2)
+checkF(function () return -((2.0^8 + -(-1)) % 8)/2 * 4 - 3 end, -5.0)
+checkF(function () return -((2^8 + -(-1)) % 8)//2 * 4 - 3 end, -7.0)
+checkI(function () return 0xF0.0 | 0xCC.0 ~ 0xAA & 0xFD end, 0xF4)
+checkI(function () return ~(~kFF0 | kFF0) end, 0)
+checkI(function () return ~~-1024.0 end, -1024)
+checkI(function () return ((100 << k6) << -4) >> 2 end, 100)
+
+-- borders around MAXARG_sBx ((((1 << 17) - 1) >> 1) == 65535)
+local a = 17; local sbx = ((1 << a) - 1) >> 1   -- avoid folding
+local border <const> = 65535
+checkI(function () return border end, sbx)
+checkI(function () return -border end, -sbx)
+checkI(function () return border + 1 end, sbx + 1)
+checkK(function () return border + 2 end, sbx + 2)
+checkK(function () return -(border + 1) end, -(sbx + 1))
+
+local border <const> = 65535.0
+checkF(function () return border end, sbx + 0.0)
+checkF(function () return -border end, -sbx + 0.0)
+checkF(function () return border + 1 end, (sbx + 1.0))
+checkK(function () return border + 2 end, (sbx + 2.0))
+checkK(function () return -(border + 1) end, -(sbx + 1.0))
+
+
+-- immediate operands
+checkR(function (x) return x + k1 end, 10, 11, 'ADDI', 'MMBINI', 'RETURN1')
+checkR(function (x) return x - 127 end, 10, -117, 'ADDI', 'MMBINI', 'RETURN1')
+checkR(function (x) return 128 + x end, 0.0, 128.0,
+         'ADDI', 'MMBINI', 'RETURN1')
+checkR(function (x) return x * -127 end, -1.0, 127.0,
+         'MULK', 'MMBINK', 'RETURN1')
+checkR(function (x) return 20 * x end, 2, 40, 'MULK', 'MMBINK', 'RETURN1')
+checkR(function (x) return x ^ -2 end, 2, 0.25, 'POWK', 'MMBINK', 'RETURN1')
+checkR(function (x) return x / 40 end, 40, 1.0, 'DIVK', 'MMBINK', 'RETURN1')
+checkR(function (x) return x // 1 end, 10.0, 10.0,
+         'IDIVK', 'MMBINK', 'RETURN1')
+checkR(function (x) return x % (100 - 10) end, 91, 1,
+         'MODK', 'MMBINK', 'RETURN1')
+checkR(function (x) return k1 << x end, 3, 8, 'SHLI', 'MMBINI', 'RETURN1')
+checkR(function (x) return x << 127 end, 10, 0, 'SHRI', 'MMBINI', 'RETURN1')
+checkR(function (x) return x << -127 end, 10, 0, 'SHRI', 'MMBINI', 'RETURN1')
+checkR(function (x) return x >> 128 end, 8, 0, 'SHRI', 'MMBINI', 'RETURN1')
+checkR(function (x) return x >> -127 end, 8, 0, 'SHRI', 'MMBINI', 'RETURN1')
+checkR(function (x) return x & 1 end, 9, 1, 'BANDK', 'MMBINK', 'RETURN1')
+checkR(function (x) return 10 | x end, 1, 11, 'BORK', 'MMBINK', 'RETURN1')
+checkR(function (x) return -10 ~ x end, -1, 9, 'BXORK', 'MMBINK', 'RETURN1')
+
+-- K operands in arithmetic operations
+checkR(function (x) return x + 0.0 end, 1, 1.0, 'ADDK', 'MMBINK', 'RETURN1')
+--  check(function (x) return 128 + x end, 'ADDK', 'MMBINK', 'RETURN1')
+checkR(function (x) return x * -10000 end, 2, -20000,
+         'MULK', 'MMBINK', 'RETURN1')
+--  check(function (x) return 20 * x end, 'MULK', 'MMBINK', 'RETURN1')
+checkR(function (x) return x ^ 0.5 end, 4, 2.0, 'POWK', 'MMBINK', 'RETURN1')
+checkR(function (x) return x / 2.0 end, 4, 2.0, 'DIVK', 'MMBINK', 'RETURN1')
+checkR(function (x) return x // 10000 end, 10000, 1,
+         'IDIVK', 'MMBINK', 'RETURN1')
+checkR(function (x) return x % (100.0 - 10) end, 91, 1.0,
+         'MODK', 'MMBINK', 'RETURN1')
+
+-- no foldings (and immediate operands)
+check(function () return -0.0 end, 'LOADF', 'UNM', 'RETURN1')
+check(function () return k3/0 end, 'LOADI', 'DIVK', 'MMBINK', 'RETURN1')
+check(function () return 0%0 end, 'LOADI', 'MODK', 'MMBINK', 'RETURN1')
+check(function () return -4//0 end, 'LOADI', 'IDIVK', 'MMBINK', 'RETURN1')
+check(function (x) return x >> 2.0 end, 'LOADF', 'SHR', 'MMBIN', 'RETURN1')
+check(function (x) return x << 128 end, 'LOADI', 'SHL', 'MMBIN', 'RETURN1')
+check(function (x) return x & 2.0 end, 'LOADF', 'BAND', 'MMBIN', 'RETURN1')
+
+-- basic 'for' loops
+check(function () for i = -10, 10.5 do end end,
+'LOADI', 'LOADK', 'LOADI', 'FORPREP', 'FORLOOP', 'RETURN0')
+check(function () for i = 0xfffffff, 10.0, 1 do end end,
+'LOADK', 'LOADF', 'LOADI', 'FORPREP', 'FORLOOP', 'RETURN0')
+
+-- bug in constant folding for 5.1
+check(function () return -nil end, 'LOADNIL', 'UNM', 'RETURN1')
+
+
+check(function ()
+  local a,b,c
+  b[c], a = c, b
+  b[a], a = c, b
+  a, b = c, a
+  a = a
+end,
+  'LOADNIL',
+  'MOVE', 'MOVE', 'SETTABLE',
+  'MOVE', 'MOVE', 'MOVE', 'SETTABLE',
+  'MOVE', 'MOVE', 'MOVE',
+  -- no code for a = a
+  'RETURN0')
+
+
+-- x == nil , x ~= nil
+-- checkequal(function (b) if (a==nil) then a=1 end; if a~=nil then a=1 end end,
+--            function () if (a==9) then a=1 end; if a~=9 then a=1 end end)
+
+-- check(function () if a==nil then a='a' end end,
+-- 'GETTABUP', 'EQ', 'JMP', 'SETTABUP', 'RETURN')
+
+do   -- tests for table access in upvalues
+  local t
+  check(function () t[kx] = t.y end, 'GETTABUP', 'SETTABUP')
+  check(function (a) t[a()] = t[a()] end,
+  'MOVE', 'CALL', 'GETUPVAL', 'MOVE', 'CALL',
+  'GETUPVAL', 'GETTABLE', 'SETTABLE')
+end
+
+-- de morgan
+checkequal(function () local a; if not (a or b) then b=a end end,
+           function () local a; if (not a and not b) then b=a end end)
+
+checkequal(function (l) local a; return 0 <= a and a <= l end,
+           function (l) local a; return not (not(a >= 0) or not(a <= l)) end)
+
+
+-- if-break optimizations
+check(function (a, b)
+        while a do
+          if b then break else a = a + 1 end
+        end
+      end,
+'TEST', 'JMP', 'TEST', 'JMP', 'ADDI', 'MMBINI', 'JMP', 'RETURN0')
+
+checkequal(
+function (a) while a < 10 do a = a + 1 end end,
+function (a)
+  ::loop::
+  if not (a < 10) then goto exit end
+  a = a + 1
+  goto loop
+::exit::
+end
+)
+
+checkequal(
+function (a) repeat local x = a + 1; a = x until a > 0 end,
+function (a)
+  ::loop:: do
+    local x = a + 1
+    a = x
+  end
+  if not (a > 0) then goto loop end
+end
+)
+
+checkequal(function () return 6 or true or nil end,
+           function () return k6 or kTrue or kNil end)
+
+checkequal(function () return 6 and true or nil end,
+           function () return k6 and kTrue or kNil end)
+
+
+do   -- string constants
+  local k0 <const> = "00000000000000000000000000000000000000000000000000"
+  local function f1 ()
+    local k <const> = k0
+    return function ()
+             return function () return k end
+           end
+  end
+
+  local f2 = f1()
+  local f3 = f2()
+  assert(f3() == k0)
+  checkK(f3, k0)
+  -- string is not needed by other functions
+  assert(T.listk(f1)[1] == nil)
+  assert(T.listk(f2)[1] == nil)
+end
+
+print 'OK'
+
diff --git a/test/external/lua-5.4.0-tests/constructs.lua b/test/external/lua-5.4.0-tests/constructs.lua
new file mode 100644
index 0000000..a74a8c0
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/constructs.lua
@@ -0,0 +1,377 @@
+-- $Id: testes/constructs.lua $
+-- See Copyright Notice in file all.lua
+
+;;print "testing syntax";;
+
+local debug = require "debug"
+
+
+local function checkload (s, msg)
+  assert(string.find(select(2, load(s)), msg))
+end
+
+-- testing semicollons
+do ;;; end
+; do ; a = 3; assert(a == 3) end;
+;
+
+
+-- invalid operations should not raise errors when not executed
+if false then a = 3 // 0; a = 0 % 0 end
+
+
+-- testing priorities
+
+assert(2^3^2 == 2^(3^2));
+assert(2^3*4 == (2^3)*4);
+assert(2.0^-2 == 1/4 and -2^- -2 == - - -4);
+assert(not nil and 2 and not(2>3 or 3<2));
+assert(-3-1-5 == 0+0-9);
+assert(-2^2 == -4 and (-2)^2 == 4 and 2*2-3-1 == 0);
+assert(-3%5 == 2 and -3+5 == 2)
+assert(2*1+3/3 == 3 and 1+2 .. 3*1 == "33");
+assert(not(2+1 > 3*1) and "a".."b" > "a");
+
+assert(0xF0 | 0xCC ~ 0xAA & 0xFD == 0xF4)
+assert(0xFD & 0xAA ~ 0xCC | 0xF0 == 0xF4)
+assert(0xF0 & 0x0F + 1 == 0x10)
+
+assert(3^4//2^3//5 == 2)
+
+assert(-3+4*5//2^3^2//9+4%10/3 == (-3)+(((4*5)//(2^(3^2)))//9)+((4%10)/3))
+
+assert(not ((true or false) and nil))
+assert(      true or false  and nil)
+
+-- old bug
+assert((((1 or false) and true) or false) == true)
+assert((((nil and true) or false) and true) == false)
+
+local a,b = 1,nil;
+assert(-(1 or 2) == -1 and (1 and 2)+(-1.25 or -4) == 0.75);
+x = ((b or a)+1 == 2 and (10 or a)+1 == 11); assert(x);
+x = (((2<3) or 1) == true and (2<3 and 4) == 4); assert(x);
+
+x,y=1,2;
+assert((x>y) and x or y == 2);
+x,y=2,1;
+assert((x>y) and x or y == 2);
+
+assert(1234567890 == tonumber('1234567890') and 1234567890+1 == 1234567891)
+
+do   -- testing operators with diffent kinds of constants
+  -- operands to consider:
+  --  * fit in register
+  --  * constant doesn't fit in register
+  --  * floats with integral values
+  local operand = {3, 100, 5.0, -10, -5.0, 10000, -10000}
+  local operator = {"+", "-", "*", "/", "//", "%", "^",
+                    "&", "|", "^", "<<", ">>",
+                    "==", "~=", "<", ">", "<=", ">=",}
+  for _, op in ipairs(operator) do
+    local f = assert(load(string.format([[return function (x,y)
+                return x %s y
+              end]], op)))();
+    for _, o1 in ipairs(operand) do
+      for _, o2 in ipairs(operand) do
+        local gab = f(o1, o2)
+
+        _ENV.XX = o1
+        code = string.format("return XX %s %s", op, o2)
+        res = assert(load(code))()
+        assert(res == gab)
+
+        _ENV.XX = o2
+        local code = string.format("return (%s) %s XX", o1, op)
+        local res = assert(load(code))()
+        assert(res == gab)
+
+        code = string.format("return (%s) %s %s", o1, op, o2)
+        res = assert(load(code))()
+        assert(res == gab)
+      end
+    end
+  end
+end
+
+
+-- silly loops
+repeat until 1; repeat until true;
+while false do end; while nil do end;
+
+do  -- test old bug (first name could not be an `upvalue')
+ local a; function f(x) x={a=1}; x={x=1}; x={G=1} end
+end
+
+function f (i)
+  if type(i) ~= 'number' then return i,'jojo'; end;
+  if i > 0 then return i, f(i-1); end;
+end
+
+x = {f(3), f(5), f(10);};
+assert(x[1] == 3 and x[2] == 5 and x[3] == 10 and x[4] == 9 and x[12] == 1);
+assert(x[nil] == nil)
+x = {f'alo', f'xixi', nil};
+assert(x[1] == 'alo' and x[2] == 'xixi' and x[3] == nil);
+x = {f'alo'..'xixi'};
+assert(x[1] == 'aloxixi')
+x = {f{}}
+assert(x[2] == 'jojo' and type(x[1]) == 'table')
+
+
+local f = function (i)
+  if i < 10 then return 'a';
+  elseif i < 20 then return 'b';
+  elseif i < 30 then return 'c';
+  end;
+end
+
+assert(f(3) == 'a' and f(12) == 'b' and f(26) == 'c' and f(100) == nil)
+
+for i=1,1000 do break; end;
+n=100;
+i=3;
+t = {};
+a=nil
+while not a do
+  a=0; for i=1,n do for i=i,1,-1 do a=a+1; t[i]=1; end; end;
+end
+assert(a == n*(n+1)/2 and i==3);
+assert(t[1] and t[n] and not t[0] and not t[n+1])
+
+function f(b)
+  local x = 1;
+  repeat
+    local a;
+    if b==1 then local b=1; x=10; break
+    elseif b==2 then x=20; break;
+    elseif b==3 then x=30;
+    else local a,b,c,d=math.sin(1); x=x+1;
+    end
+  until x>=12;
+  return x;
+end;
+
+assert(f(1) == 10 and f(2) == 20 and f(3) == 30 and f(4)==12)
+
+
+local f = function (i)
+  if i < 10 then return 'a'
+  elseif i < 20 then return 'b'
+  elseif i < 30 then return 'c'
+  else return 8
+  end
+end
+
+assert(f(3) == 'a' and f(12) == 'b' and f(26) == 'c' and f(100) == 8)
+
+local a, b = nil, 23
+x = {f(100)*2+3 or a, a or b+2}
+assert(x[1] == 19 and x[2] == 25)
+x = {f=2+3 or a, a = b+2}
+assert(x.f == 5 and x.a == 25)
+
+a={y=1}
+x = {a.y}
+assert(x[1] == 1)
+
+function f(i)
+  while 1 do
+    if i>0 then i=i-1;
+    else return; end;
+  end;
+end;
+
+function g(i)
+  while 1 do
+    if i>0 then i=i-1
+    else return end
+  end
+end
+
+f(10); g(10);
+
+do
+  function f () return 1,2,3; end
+  local a, b, c = f();
+  assert(a==1 and b==2 and c==3)
+  a, b, c = (f());
+  assert(a==1 and b==nil and c==nil)
+end
+
+local a,b = 3 and f();
+assert(a==1 and b==nil)
+
+function g() f(); return; end;
+assert(g() == nil)
+function g() return nil or f() end
+a,b = g()
+assert(a==1 and b==nil)
+
+print'+';
+
+do   -- testing constants
+  local prog <const> = [[local x <XXX> = 10]]
+  checkload(prog, "unknown attribute 'XXX'")
+
+  checkload([[local xxx <const> = 20; xxx = 10]],
+             ":1: attempt to assign to const variable 'xxx'")
+
+  checkload([[
+    local xx;
+    local xxx <const> = 20;
+    local yyy;
+    local function foo ()
+      local abc = xx + yyy + xxx;
+      return function () return function () xxx = yyy end end
+    end
+  ]], ":6: attempt to assign to const variable 'xxx'")
+
+  checkload([[
+    local x <close> = nil
+    x = io.open()
+  ]], ":2: attempt to assign to const variable 'x'")
+end
+
+f = [[
+return function ( a , b , c , d , e )
+  local x = a >= b or c or ( d and e ) or nil
+  return x
+end , { a = 1 , b = 2 >= 1 , } or { 1 };
+]]
+f = string.gsub(f, "%s+", "\n");   -- force a SETLINE between opcodes
+f,a = load(f)();
+assert(a.a == 1 and a.b)
+
+function g (a,b,c,d,e)
+  if not (a>=b or c or d and e or nil) then return 0; else return 1; end;
+end
+
+function h (a,b,c,d,e)
+  while (a>=b or c or (d and e) or nil) do return 1; end;
+  return 0;
+end;
+
+assert(f(2,1) == true and g(2,1) == 1 and h(2,1) == 1)
+assert(f(1,2,'a') == 'a' and g(1,2,'a') == 1 and h(1,2,'a') == 1)
+assert(f(1,2,'a')
+~=          -- force SETLINE before nil
+nil, "")
+assert(f(1,2,'a') == 'a' and g(1,2,'a') == 1 and h(1,2,'a') == 1)
+assert(f(1,2,nil,1,'x') == 'x' and g(1,2,nil,1,'x') == 1 and
+                                   h(1,2,nil,1,'x') == 1)
+assert(f(1,2,nil,nil,'x') == nil and g(1,2,nil,nil,'x') == 0 and
+                                     h(1,2,nil,nil,'x') == 0)
+assert(f(1,2,nil,1,nil) == nil and g(1,2,nil,1,nil) == 0 and
+                                   h(1,2,nil,1,nil) == 0)
+
+assert(1 and 2<3 == true and 2<3 and 'a'<'b' == true)
+x = 2<3 and not 3; assert(x==false)
+x = 2<1 or (2>1 and 'a'); assert(x=='a')
+
+
+do
+  local a; if nil then a=1; else a=2; end;    -- this nil comes as PUSHNIL 2
+  assert(a==2)
+end
+
+function F(a)
+  assert(debug.getinfo(1, "n").name == 'F')
+  return a,2,3
+end
+
+a,b = F(1)~=nil; assert(a == true and b == nil);
+a,b = F(nil)==nil; assert(a == true and b == nil)
+
+----------------------------------------------------------------
+------------------------------------------------------------------
+
+-- sometimes will be 0, sometimes will not...
+_ENV.GLOB1 = math.random(0, 1)
+
+-- basic expressions with their respective values
+local basiccases = {
+  {"nil", nil},
+  {"false", false},
+  {"true", true},
+  {"10", 10},
+  {"(0==_ENV.GLOB1)", 0 == _ENV.GLOB1},
+}
+
+local prog
+
+if _ENV.GLOB1 == 0 then
+  basiccases[2][1] = "F"   -- constant false
+
+  prog = [[
+    local F <const> = false
+    if %s then IX = true end
+    return %s
+]]
+else
+  basiccases[4][1] = "k10"   -- constant 10
+
+  prog = [[
+    local k10 <const> = 10
+    if %s then IX = true end
+    return %s
+  ]]
+end
+
+print('testing short-circuit optimizations (' .. _ENV.GLOB1 .. ')')
+
+
+-- operators with their respective values
+local binops <const> = {
+  {" and ", function (a,b) if not a then return a else return b end end},
+  {" or ", function (a,b) if a then return a else return b end end},
+}
+
+local cases <const> = {}
+
+-- creates all combinations of '(cases[i] op cases[n-i])' plus
+-- 'not(cases[i] op cases[n-i])' (syntax + value)
+local function createcases (n)
+  local res = {}
+  for i = 1, n - 1 do
+    for _, v1 in ipairs(cases[i]) do
+      for _, v2 in ipairs(cases[n - i]) do
+        for _, op in ipairs(binops) do
+            local t = {
+              "(" .. v1[1] .. op[1] .. v2[1] .. ")",
+              op[2](v1[2], v2[2])
+            }
+            res[#res + 1] = t
+            res[#res + 1] = {"not" .. t[1], not t[2]}
+        end
+      end
+    end
+  end
+  return res
+end
+
+-- do not do too many combinations for soft tests
+local level = _soft and 3 or 4
+
+cases[1] = basiccases
+for i = 2, level do cases[i] = createcases(i) end
+print("+")
+
+local i = 0
+for n = 1, level do
+  for _, v in pairs(cases[n]) do
+    local s = v[1]
+    local p = load(string.format(prog, s, s), "")
+    IX = false
+    assert(p() == v[2] and IX == not not v[2])
+    i = i + 1
+    if i % 60000 == 0 then print('+') end
+  end
+end
+------------------------------------------------------------------
+
+-- testing some syntax errors (chosen through 'gcov')
+checkload("for x do", "expected")
+checkload("x:call", "expected")
+
+print'OK'
diff --git a/test/external/lua-5.4.0-tests/coroutine.lua b/test/external/lua-5.4.0-tests/coroutine.lua
new file mode 100644
index 0000000..73333c1
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/coroutine.lua
@@ -0,0 +1,1015 @@
+-- $Id: testes/coroutine.lua $
+-- See Copyright Notice in file all.lua
+
+print "testing coroutines"
+
+local debug = require'debug'
+
+local f
+
+local main, ismain = coroutine.running()
+assert(type(main) == "thread" and ismain)
+assert(not coroutine.resume(main))
+assert(not coroutine.isyieldable(main) and not coroutine.isyieldable())
+assert(not pcall(coroutine.yield))
+
+
+-- trivial errors
+assert(not pcall(coroutine.resume, 0))
+assert(not pcall(coroutine.status, 0))
+
+
+-- tests for multiple yield/resume arguments
+
+local function eqtab (t1, t2)
+  assert(#t1 == #t2)
+  for i = 1, #t1 do
+    local v = t1[i]
+    assert(t2[i] == v)
+  end
+end
+
+_G.x = nil   -- declare x
+function foo (a, ...)
+  local x, y = coroutine.running()
+  assert(x == f and y == false)
+  -- next call should not corrupt coroutine (but must fail,
+  -- as it attempts to resume the running coroutine)
+  assert(coroutine.resume(f) == false)
+  assert(coroutine.status(f) == "running")
+  local arg = {...}
+  assert(coroutine.isyieldable(x))
+  for i=1,#arg do
+    _G.x = {coroutine.yield(table.unpack(arg[i]))}
+  end
+  return table.unpack(a)
+end
+
+f = coroutine.create(foo)
+assert(coroutine.isyieldable(f))
+assert(type(f) == "thread" and coroutine.status(f) == "suspended")
+assert(string.find(tostring(f), "thread"))
+local s,a,b,c,d
+s,a,b,c,d = coroutine.resume(f, {1,2,3}, {}, {1}, {'a', 'b', 'c'})
+assert(coroutine.isyieldable(f))
+assert(s and a == nil and coroutine.status(f) == "suspended")
+s,a,b,c,d = coroutine.resume(f)
+eqtab(_G.x, {})
+assert(s and a == 1 and b == nil)
+assert(coroutine.isyieldable(f))
+s,a,b,c,d = coroutine.resume(f, 1, 2, 3)
+eqtab(_G.x, {1, 2, 3})
+assert(s and a == 'a' and b == 'b' and c == 'c' and d == nil)
+s,a,b,c,d = coroutine.resume(f, "xuxu")
+eqtab(_G.x, {"xuxu"})
+assert(s and a == 1 and b == 2 and c == 3 and d == nil)
+assert(coroutine.status(f) == "dead")
+s, a = coroutine.resume(f, "xuxu")
+assert(not s and string.find(a, "dead") and coroutine.status(f) == "dead")
+
+
+-- yields in tail calls
+local function foo (i) return coroutine.yield(i) end
+f = coroutine.wrap(function ()
+  for i=1,10 do
+    assert(foo(i) == _G.x)
+  end
+  return 'a'
+end)
+for i=1,10 do _G.x = i; assert(f(i) == i) end
+_G.x = 'xuxu'; assert(f('xuxu') == 'a')
+
+-- recursive
+function pf (n, i)
+  coroutine.yield(n)
+  pf(n*i, i+1)
+end
+
+f = coroutine.wrap(pf)
+local s=1
+for i=1,10 do
+  assert(f(1, 1) == s)
+  s = s*i
+end
+
+-- sieve
+function gen (n)
+  return coroutine.wrap(function ()
+    for i=2,n do coroutine.yield(i) end
+  end)
+end
+
+
+function filter (p, g)
+  return coroutine.wrap(function ()
+    while 1 do
+      local n = g()
+      if n == nil then return end
+      if math.fmod(n, p) ~= 0 then coroutine.yield(n) end
+    end
+  end)
+end
+
+local x = gen(80)
+local a = {}
+while 1 do
+  local n = x()
+  if n == nil then break end
+  table.insert(a, n)
+  x = filter(n, x)
+end
+
+assert(#a == 22 and a[#a] == 79)
+x, a = nil
+
+
+-- coroutine closing
+do
+  -- ok to close a dead coroutine
+  local co = coroutine.create(print)
+  assert(coroutine.resume(co, "testing 'coroutine.close'"))
+  assert(coroutine.status(co) == "dead")
+  assert(coroutine.close(co))
+
+  -- cannot close the running coroutine
+  local st, msg = pcall(coroutine.close, coroutine.running())
+  assert(not st and string.find(msg, "running"))
+
+  local main = coroutine.running()
+
+  -- cannot close a "normal" coroutine
+  ;(coroutine.wrap(function ()
+    local st, msg = pcall(coroutine.close, main)
+    assert(not st and string.find(msg, "normal"))
+  end))()
+
+  -- to-be-closed variables in coroutines
+  local X
+
+  local function func2close (f)
+    return setmetatable({}, {__close = f})
+  end
+
+  co = coroutine.create(function ()
+    local x <close> = func2close(function (self, err)
+      assert(err == nil); X = false
+    end)
+    X = true
+    coroutine.yield()
+  end)
+  coroutine.resume(co)
+  assert(X)
+  assert(coroutine.close(co))
+  assert(not X and coroutine.status(co) == "dead")
+
+  -- error closing a coroutine
+  warn("@on")
+  local x = 0
+  co = coroutine.create(function()
+    local y <close> = func2close(function (self,err)
+      if (err ~= 111) then os.exit(false) end   -- should not happen
+      x = 200
+      error("200")
+    end)
+    local x <close> = func2close(function (self, err)
+      assert(err == nil); error(111)
+    end)
+    coroutine.yield()
+  end)
+  coroutine.resume(co)
+  assert(x == 0)
+  -- with test library, use 'store' mode to check warnings
+  warn(not T and "@off" or "@store")
+  local st, msg = coroutine.close(co)
+  if not T then
+    warn("@on")
+  else   -- test library
+    assert(string.find(_WARN, "200")); _WARN = nil
+    warn("@normal")
+  end
+  assert(st == false and coroutine.status(co) == "dead" and msg == 111)
+  assert(x == 200)
+
+end
+
+
+-- yielding across C boundaries
+
+co = coroutine.wrap(function()
+       assert(not pcall(table.sort,{1,2,3}, coroutine.yield))
+       assert(coroutine.isyieldable())
+       coroutine.yield(20)
+       return 30
+     end)
+
+assert(co() == 20)
+assert(co() == 30)
+
+
+local f = function (s, i) return coroutine.yield(i) end
+
+local f1 = coroutine.wrap(function ()
+             return xpcall(pcall, function (...) return ... end,
+               function ()
+                 local s = 0
+                 for i in f, nil, 1 do pcall(function () s = s + i end) end
+                 error({s})
+               end)
+           end)
+
+f1()
+for i = 1, 10 do assert(f1(i) == i) end
+local r1, r2, v = f1(nil)
+assert(r1 and not r2 and v[1] ==  (10 + 1)*10/2)
+
+
+function f (a, b) a = coroutine.yield(a);  error{a + b} end
+function g(x) return x[1]*2 end
+
+co = coroutine.wrap(function ()
+       coroutine.yield(xpcall(f, g, 10, 20))
+     end)
+
+assert(co() == 10)
+r, msg = co(100)
+assert(not r and msg == 240)
+
+
+-- unyieldable C call
+do
+  local function f (c)
+          assert(not coroutine.isyieldable())
+          return c .. c
+        end
+
+  local co = coroutine.wrap(function (c)
+               assert(coroutine.isyieldable())
+               local s = string.gsub("a", ".", f)
+               return s
+             end)
+  assert(co() == "aa")
+end
+
+
+
+do   -- testing single trace of coroutines
+  local X
+  local co = coroutine.create(function ()
+    coroutine.yield(10)
+    return 20;
+  end)
+  local trace = {}
+  local function dotrace (event)
+    trace[#trace + 1] = event
+  end
+  debug.sethook(co, dotrace, "clr")
+  repeat until not coroutine.resume(co)
+  local correcttrace = {"call", "line", "call", "return", "line", "return"}
+  assert(#trace == #correcttrace)
+  for k, v in pairs(trace) do
+    assert(v == correcttrace[k])
+  end
+end
+
+-- errors in coroutines
+function foo ()
+  assert(debug.getinfo(1).currentline == debug.getinfo(foo).linedefined + 1)
+  assert(debug.getinfo(2).currentline == debug.getinfo(goo).linedefined)
+  coroutine.yield(3)
+  error(foo)
+end
+
+function goo() foo() end
+x = coroutine.wrap(goo)
+assert(x() == 3)
+local a,b = pcall(x)
+assert(not a and b == foo)
+
+x = coroutine.create(goo)
+a,b = coroutine.resume(x)
+assert(a and b == 3)
+a,b = coroutine.resume(x)
+assert(not a and b == foo and coroutine.status(x) == "dead")
+a,b = coroutine.resume(x)
+assert(not a and string.find(b, "dead") and coroutine.status(x) == "dead")
+
+
+-- co-routines x for loop
+function all (a, n, k)
+  if k == 0 then coroutine.yield(a)
+  else
+    for i=1,n do
+      a[k] = i
+      all(a, n, k-1)
+    end
+  end
+end
+
+local a = 0
+for t in coroutine.wrap(function () all({}, 5, 4) end) do
+  a = a+1
+end
+assert(a == 5^4)
+
+
+-- access to locals of collected corroutines
+local C = {}; setmetatable(C, {__mode = "kv"})
+local x = coroutine.wrap (function ()
+            local a = 10
+            local function f () a = a+10; return a end
+            while true do
+              a = a+1
+              coroutine.yield(f)
+            end
+          end)
+
+C[1] = x;
+
+local f = x()
+assert(f() == 21 and x()() == 32 and x() == f)
+x = nil
+collectgarbage()
+assert(C[1] == undef)
+assert(f() == 43 and f() == 53)
+
+
+-- old bug: attempt to resume itself
+
+function co_func (current_co)
+  assert(coroutine.running() == current_co)
+  assert(coroutine.resume(current_co) == false)
+  coroutine.yield(10, 20)
+  assert(coroutine.resume(current_co) == false)
+  coroutine.yield(23)
+  return 10
+end
+
+local co = coroutine.create(co_func)
+local a,b,c = coroutine.resume(co, co)
+assert(a == true and b == 10 and c == 20)
+a,b = coroutine.resume(co, co)
+assert(a == true and b == 23)
+a,b = coroutine.resume(co, co)
+assert(a == true and b == 10)
+assert(coroutine.resume(co, co) == false)
+assert(coroutine.resume(co, co) == false)
+
+
+-- other old bug when attempting to resume itself
+-- (trigger C-code assertions)
+do
+  local A = coroutine.running()
+  local B = coroutine.create(function() return coroutine.resume(A) end)
+  local st, res = coroutine.resume(B)
+  assert(st == true and res == false)
+
+  local X = false
+  A = coroutine.wrap(function()
+    local _ <close> = setmetatable({}, {__close = function () X = true end})
+    return pcall(A, 1)
+  end)
+  st, res = A()
+  assert(not st and string.find(res, "non%-suspended") and X == true)
+end
+
+
+-- attempt to resume 'normal' coroutine
+local co1, co2
+co1 = coroutine.create(function () return co2() end)
+co2 = coroutine.wrap(function ()
+        assert(coroutine.status(co1) == 'normal')
+        assert(not coroutine.resume(co1))
+        coroutine.yield(3)
+      end)
+
+a,b = coroutine.resume(co1)
+assert(a and b == 3)
+assert(coroutine.status(co1) == 'dead')
+
+-- infinite recursion of coroutines
+a = function(a) coroutine.wrap(a)(a) end
+assert(not pcall(a, a))
+a = nil
+
+
+-- access to locals of erroneous coroutines
+local x = coroutine.create (function ()
+            local a = 10
+            _G.f = function () a=a+1; return a end
+            error('x')
+          end)
+
+assert(not coroutine.resume(x))
+-- overwrite previous position of local `a'
+assert(not coroutine.resume(x, 1, 1, 1, 1, 1, 1, 1))
+assert(_G.f() == 11)
+assert(_G.f() == 12)
+
+
+if not T then
+  (Message or print)('\n >>> testC not active: skipping yield/hook tests <<<\n')
+else
+  print "testing yields inside hooks"
+
+  local turn
+  
+  function fact (t, x)
+    assert(turn == t)
+    if x == 0 then return 1
+    else return x*fact(t, x-1)
+    end
+  end
+
+  local A, B = 0, 0
+
+  local x = coroutine.create(function ()
+    T.sethook("yield 0", "", 2)
+    A = fact("A", 6)
+  end)
+
+  local y = coroutine.create(function ()
+    T.sethook("yield 0", "", 3)
+    B = fact("B", 7)
+  end)
+
+  while A==0 or B==0 do    -- A ~= 0 when 'x' finishes (similar for 'B','y')
+    if A==0 then turn = "A"; assert(T.resume(x)) end
+    if B==0 then turn = "B"; assert(T.resume(y)) end
+
+    -- check that traceback works correctly after yields inside hooks
+    debug.traceback(x)
+    debug.traceback(y)
+  end
+
+  assert(B // A == 7)    -- fact(7) // fact(6)
+
+  local line = debug.getinfo(1, "l").currentline + 2    -- get line number
+  local function foo ()
+    local x = 10    --<< this line is 'line'
+    x = x + 10
+    _G.XX = x
+  end
+
+  -- testing yields in line hook
+  local co = coroutine.wrap(function ()
+    T.sethook("setglobal X; yield 0", "l", 0); foo(); return 10 end)
+
+  _G.XX = nil;
+  _G.X = nil; co(); assert(_G.X == line)
+  _G.X = nil; co(); assert(_G.X == line + 1)
+  _G.X = nil; co(); assert(_G.X == line + 2 and _G.XX == nil)
+  _G.X = nil; co(); assert(_G.X == line + 3 and _G.XX == 20)
+  assert(co() == 10)
+
+  -- testing yields in count hook
+  co = coroutine.wrap(function ()
+    T.sethook("yield 0", "", 1); foo(); return 10 end)
+
+  _G.XX = nil;
+  local c = 0
+  repeat c = c + 1; local a = co() until a == 10
+  assert(_G.XX == 20 and c >= 5)
+
+  co = coroutine.wrap(function ()
+    T.sethook("yield 0", "", 2); foo(); return 10 end)
+
+  _G.XX = nil;
+  local c = 0
+  repeat c = c + 1; local a = co() until a == 10
+  assert(_G.XX == 20 and c >= 5)
+  _G.X = nil; _G.XX = nil
+
+  do
+    -- testing debug library on a coroutine suspended inside a hook
+    -- (bug in 5.2/5.3)
+    c = coroutine.create(function (a, ...)
+      T.sethook("yield 0", "l")   -- will yield on next two lines
+      assert(a == 10)
+      return ...
+    end)
+
+    assert(coroutine.resume(c, 1, 2, 3))   -- start coroutine
+    local n,v = debug.getlocal(c, 0, 1)    -- check its local
+    assert(n == "a" and v == 1)
+    assert(debug.setlocal(c, 0, 1, 10))     -- test 'setlocal'
+    local t = debug.getinfo(c, 0)        -- test 'getinfo'
+    assert(t.currentline == t.linedefined + 1)
+    assert(not debug.getinfo(c, 1))      -- no other level
+    assert(coroutine.resume(c))          -- run next line
+    v = {coroutine.resume(c)}         -- finish coroutine
+    assert(v[1] == true and v[2] == 2 and v[3] == 3 and v[4] == undef)
+    assert(not coroutine.resume(c))
+  end
+
+  do
+    -- testing debug library on last function in a suspended coroutine
+    -- (bug in 5.2/5.3)
+    local c = coroutine.create(function () T.testC("yield 1", 10, 20) end)
+    local a, b = coroutine.resume(c)
+    assert(a and b == 20)
+    assert(debug.getinfo(c, 0).linedefined == -1)
+    a, b = debug.getlocal(c, 0, 2)
+    assert(b == 10)
+  end
+
+
+  print "testing coroutine API"
+  
+  -- reusing a thread
+  assert(T.testC([[
+    newthread      # create thread
+    pushvalue 2    # push body
+    pushstring 'a a a'  # push argument
+    xmove 0 3 2   # move values to new thread
+    resume -1, 1    # call it first time
+    pushstatus
+    xmove 3 0 0   # move results back to stack
+    setglobal X    # result
+    setglobal Y    # status
+    pushvalue 2     # push body (to call it again)
+    pushstring 'b b b'
+    xmove 0 3 2
+    resume -1, 1    # call it again
+    pushstatus
+    xmove 3 0 0
+    return 1        # return result
+  ]], function (...) return ... end) == 'b b b')
+
+  assert(X == 'a a a' and Y == 'OK')
+
+
+  -- resuming running coroutine
+  C = coroutine.create(function ()
+        return T.testC([[
+                 pushnum 10;
+                 pushnum 20;
+                 resume -3 2;
+                 pushstatus
+                 gettop;
+                 return 3]], C)
+      end)
+  local a, b, c, d = coroutine.resume(C)
+  assert(a == true and string.find(b, "non%-suspended") and
+         c == "ERRRUN" and d == 4)
+
+  a, b, c, d = T.testC([[
+    rawgeti R 1    # get main thread
+    pushnum 10;
+    pushnum 20;
+    resume -3 2;
+    pushstatus
+    gettop;
+    return 4]])
+  assert(a == coroutine.running() and string.find(b, "non%-suspended") and
+         c == "ERRRUN" and d == 4)
+
+
+  -- using a main thread as a coroutine
+  local state = T.newstate()
+  T.loadlib(state)
+
+  assert(T.doremote(state, [[
+    coroutine = require'coroutine';
+    X = function (x) coroutine.yield(x, 'BB'); return 'CC' end;
+    return 'ok']]))
+
+  t = table.pack(T.testC(state, [[
+    rawgeti R 1     # get main thread
+    pushstring 'XX'
+    getglobal X    # get function for body
+    pushstring AA      # arg
+    resume 1 1      # 'resume' shadows previous stack!
+    gettop
+    setglobal T    # top
+    setglobal B    # second yielded value
+    setglobal A    # fist yielded value
+    rawgeti R 1     # get main thread
+    pushnum 5       # arg (noise)
+    resume 1 1      # after coroutine ends, previous stack is back
+    pushstatus
+    return *
+  ]]))
+  assert(t.n == 4 and t[2] == 'XX' and t[3] == 'CC' and t[4] == 'OK')
+  assert(T.doremote(state, "return T") == '2')
+  assert(T.doremote(state, "return A") == 'AA')
+  assert(T.doremote(state, "return B") == 'BB')
+
+  T.closestate(state)
+
+  print'+'
+
+end
+
+
+-- leaving a pending coroutine open
+_X = coroutine.wrap(function ()
+      local a = 10
+      local x = function () a = a+1 end
+      coroutine.yield()
+    end)
+
+_X()
+
+
+if not _soft then
+  -- bug (stack overflow)
+  local j = 2^9
+  local lim = 1000000    -- (C stack limit; assume 32-bit machine)
+  local t = {lim - 10, lim - 5, lim - 1, lim, lim + 1}
+  for i = 1, #t do
+    local j = t[i]
+    co = coroutine.create(function()
+           local t = {}
+           for i = 1, j do t[i] = i end
+           return table.unpack(t)
+         end)
+    local r, msg = coroutine.resume(co)
+    assert(not r)
+  end
+  co = nil
+end
+
+
+assert(coroutine.running() == main)
+
+print"+"
+
+
+print"testing yields inside metamethods"
+
+local function val(x)
+  if type(x) == "table" then return x.x else return x end
+end
+
+local mt = {
+  __eq = function(a,b) coroutine.yield(nil, "eq"); return val(a) == val(b) end,
+  __lt = function(a,b) coroutine.yield(nil, "lt"); return val(a) < val(b) end,
+  __le = function(a,b) coroutine.yield(nil, "le"); return a - b <= 0 end,
+  __add = function(a,b) coroutine.yield(nil, "add");
+                        return val(a) + val(b) end,
+  __sub = function(a,b) coroutine.yield(nil, "sub"); return val(a) - val(b) end,
+  __mul = function(a,b) coroutine.yield(nil, "mul"); return val(a) * val(b) end,
+  __div = function(a,b) coroutine.yield(nil, "div"); return val(a) / val(b) end,
+  __idiv = function(a,b) coroutine.yield(nil, "idiv");
+                         return val(a) // val(b) end,
+  __pow = function(a,b) coroutine.yield(nil, "pow"); return val(a) ^ val(b) end,
+  __mod = function(a,b) coroutine.yield(nil, "mod"); return val(a) % val(b) end,
+  __unm = function(a,b) coroutine.yield(nil, "unm"); return -val(a) end,
+  __bnot = function(a,b) coroutine.yield(nil, "bnot"); return ~val(a) end,
+  __shl = function(a,b) coroutine.yield(nil, "shl");
+                        return val(a) << val(b) end,
+  __shr = function(a,b) coroutine.yield(nil, "shr");
+                        return val(a) >> val(b) end,
+  __band = function(a,b)
+             coroutine.yield(nil, "band")
+             return val(a) & val(b)
+           end,
+  __bor = function(a,b) coroutine.yield(nil, "bor");
+                        return val(a) | val(b) end,
+  __bxor = function(a,b) coroutine.yield(nil, "bxor");
+                         return val(a) ~ val(b) end,
+
+  __concat = function(a,b)
+               coroutine.yield(nil, "concat");
+               return val(a) .. val(b)
+             end,
+  __index = function (t,k) coroutine.yield(nil, "idx"); return t.k[k] end,
+  __newindex = function (t,k,v) coroutine.yield(nil, "nidx"); t.k[k] = v end,
+}
+
+
+local function new (x)
+  return setmetatable({x = x, k = {}}, mt)
+end
+
+
+local a = new(10)
+local b = new(12)
+local c = new"hello"
+
+local function run (f, t)
+  local i = 1
+  local c = coroutine.wrap(f)
+  while true do
+    local res, stat = c()
+    if res then assert(t[i] == undef); return res, t end
+    assert(stat == t[i])
+    i = i + 1
+  end
+end
+
+
+assert(run(function () if (a>=b) then return '>=' else return '<' end end,
+       {"le", "sub"}) == "<")
+assert(run(function () if (a<=b) then return '<=' else return '>' end end,
+       {"le", "sub"}) == "<=")
+assert(run(function () if (a==b) then return '==' else return '~=' end end,
+       {"eq"}) == "~=")
+
+assert(run(function () return a & b + a end, {"add", "band"}) == 2)
+
+assert(run(function () return 1 + a end, {"add"}) == 11)
+assert(run(function () return a - 25 end, {"sub"}) == -15)
+assert(run(function () return 2 * a end, {"mul"}) == 20)
+assert(run(function () return a ^ 2 end, {"pow"}) == 100)
+assert(run(function () return a / 2 end, {"div"}) == 5)
+assert(run(function () return a % 6 end, {"mod"}) == 4)
+assert(run(function () return a // 3 end, {"idiv"}) == 3)
+
+assert(run(function () return a + b end, {"add"}) == 22)
+assert(run(function () return a - b end, {"sub"}) == -2)
+assert(run(function () return a * b end, {"mul"}) == 120)
+assert(run(function () return a ^ b end, {"pow"}) == 10^12)
+assert(run(function () return a / b end, {"div"}) == 10/12)
+assert(run(function () return a % b end, {"mod"}) == 10)
+assert(run(function () return a // b end, {"idiv"}) == 0)
+
+-- repeat tests with larger constants (to use 'K' opcodes)
+local a1000 = new(1000)
+
+assert(run(function () return a1000 + 1000 end, {"add"}) == 2000)
+assert(run(function () return a1000 - 25000 end, {"sub"}) == -24000)
+assert(run(function () return 2000 * a end, {"mul"}) == 20000)
+assert(run(function () return a1000 / 1000 end, {"div"}) == 1)
+assert(run(function () return a1000 % 600 end, {"mod"}) == 400)
+assert(run(function () return a1000 // 500 end, {"idiv"}) == 2)
+
+
+
+assert(run(function () return a % b end, {"mod"}) == 10)
+
+assert(run(function () return ~a & b end, {"bnot", "band"}) == ~10 & 12)
+assert(run(function () return a | b end, {"bor"}) == 10 | 12)
+assert(run(function () return a ~ b end, {"bxor"}) == 10 ~ 12)
+assert(run(function () return a << b end, {"shl"}) == 10 << 12)
+assert(run(function () return a >> b end, {"shr"}) == 10 >> 12)
+
+assert(run(function () return 10 & b end, {"band"}) == 10 & 12)
+assert(run(function () return a | 2 end, {"bor"}) == 10 | 2)
+assert(run(function () return a ~ 2 end, {"bxor"}) == 10 ~ 2)
+assert(run(function () return a >> 2 end, {"shr"}) == 10 >> 2)
+assert(run(function () return 1 >> a end, {"shr"}) == 1 >> 10)
+assert(run(function () return a << 2 end, {"shl"}) == 10 << 2)
+assert(run(function () return 1 << a end, {"shl"}) == 1 << 10)
+assert(run(function () return 2 ~ a end, {"bxor"}) == 2 ~ 10)
+
+
+assert(run(function () return a..b end, {"concat"}) == "1012")
+
+assert(run(function() return a .. b .. c .. a end,
+       {"concat", "concat", "concat"}) == "1012hello10")
+
+assert(run(function() return "a" .. "b" .. a .. "c" .. c .. b .. "x" end,
+       {"concat", "concat", "concat"}) == "ab10chello12x")
+
+
+do   -- a few more tests for comparison operators
+  local mt1 = {
+    __le = function (a,b)
+      coroutine.yield(10)
+      return (val(a) <= val(b))
+    end,
+    __lt = function (a,b)
+      coroutine.yield(10)
+      return val(a) < val(b)
+    end,
+  }
+  local mt2 = { __lt = mt1.__lt, __le = mt1.__le }
+
+  local function run (f)
+    local co = coroutine.wrap(f)
+    local res
+    repeat
+      res = co()
+    until res ~= 10
+    return res
+  end
+  
+  local function test ()
+    local a1 = setmetatable({x=1}, mt1)
+    local a2 = setmetatable({x=2}, mt2)
+    assert(a1 < a2)
+    assert(a1 <= a2)
+    assert(1 < a2)
+    assert(1 <= a2)
+    assert(2 > a1)
+    assert(2 >= a2)
+    return true
+  end
+  
+  run(test)
+
+end
+
+assert(run(function ()
+             a.BB = print
+             return a.BB
+           end, {"nidx", "idx"}) == print)
+
+-- getuptable & setuptable
+do local _ENV = _ENV
+  f = function () AAA = BBB + 1; return AAA end
+end
+g = new(10); g.k.BBB = 10;
+debug.setupvalue(f, 1, g)
+assert(run(f, {"idx", "nidx", "idx"}) == 11)
+assert(g.k.AAA == 11)
+
+print"+"
+
+print"testing yields inside 'for' iterators"
+
+local f = function (s, i)
+      if i%2 == 0 then coroutine.yield(nil, "for") end
+      if i < s then return i + 1 end
+    end
+
+assert(run(function ()
+             local s = 0
+             for i in f, 4, 0 do s = s + i end
+             return s
+           end, {"for", "for", "for"}) == 10)
+
+
+
+-- tests for coroutine API
+if T==nil then
+  (Message or print)('\n >>> testC not active: skipping coroutine API tests <<<\n')
+  print "OK"; return
+end
+
+print('testing coroutine API')
+
+local function apico (...)
+  local x = {...}
+  return coroutine.wrap(function ()
+    return T.testC(table.unpack(x))
+  end)
+end
+
+local a = {apico(
+[[
+  pushstring errorcode
+  pcallk 1 0 2;
+  invalid command (should not arrive here)
+]],
+[[return *]],
+"stackmark",
+error
+)()}
+assert(#a == 4 and
+       a[3] == "stackmark" and
+       a[4] == "errorcode" and
+       _G.status == "ERRRUN" and
+       _G.ctx == 2)       -- 'ctx' to pcallk
+
+local co = apico(
+  "pushvalue 2; pushnum 10; pcallk 1 2 3; invalid command;",
+  coroutine.yield,
+  "getglobal status; getglobal ctx; pushvalue 2; pushstring a; pcallk 1 0 4; invalid command",
+  "getglobal status; getglobal ctx; return *")
+
+assert(co() == 10)
+assert(co(20, 30) == 'a')
+a = {co()}
+assert(#a == 10 and
+       a[2] == coroutine.yield and
+       a[5] == 20 and a[6] == 30 and
+       a[7] == "YIELD" and a[8] == 3 and
+       a[9] == "YIELD" and a[10] == 4)
+assert(not pcall(co))   -- coroutine is dead now
+
+
+f = T.makeCfunc("pushnum 3; pushnum 5; yield 1;")
+co = coroutine.wrap(function ()
+  assert(f() == 23); assert(f() == 23); return 10
+end)
+assert(co(23,16) == 5)
+assert(co(23,16) == 5)
+assert(co(23,16) == 10)
+
+
+-- testing coroutines with C bodies
+f = T.makeCfunc([[
+        pushnum 102
+	yieldk	1 U2
+	cannot be here!
+]],
+[[      # continuation
+	pushvalue U3   # accessing upvalues inside a continuation
+        pushvalue U4
+	return *
+]], 23, "huu")
+
+x = coroutine.wrap(f)
+assert(x() == 102)
+eqtab({x()}, {23, "huu"})
+
+
+f = T.makeCfunc[[pushstring 'a'; pushnum 102; yield 2; ]]
+
+a, b, c, d = T.testC([[newthread; pushvalue 2; xmove 0 3 1; resume 3 0;
+                       pushstatus; xmove 3 0 0;  resume 3 0; pushstatus;
+                       return 4; ]], f)
+
+assert(a == 'YIELD' and b == 'a' and c == 102 and d == 'OK')
+
+
+-- testing chain of suspendable C calls
+
+local count = 3   -- number of levels
+
+f = T.makeCfunc([[
+  remove 1;             # remove argument
+  pushvalue U3;         # get selection function
+  call 0 1;             # call it  (result is 'f' or 'yield')
+  pushstring hello      # single argument for selected function
+  pushupvalueindex 2;   # index of continuation program
+  callk 1 -1 .;		# call selected function
+  errorerror		# should never arrive here
+]],
+[[
+  # continuation program
+  pushnum 34	# return value
+  return *     # return all results
+]],
+function ()     -- selection function
+  count = count - 1
+  if count == 0 then return coroutine.yield
+  else return f
+  end
+end
+)
+
+co = coroutine.wrap(function () return f(nil) end)
+assert(co() == "hello")   -- argument to 'yield'
+a = {co()}
+-- three '34's (one from each pending C call)
+assert(#a == 3 and a[1] == a[2] and a[2] == a[3] and a[3] == 34)
+
+
+-- testing yields with continuations
+
+co = coroutine.wrap(function (...) return
+       T.testC([[ # initial function
+          yieldk 1 2
+          cannot be here!
+       ]],
+       [[  # 1st continuation
+         yieldk 0 3 
+         cannot be here!
+       ]],
+       [[  # 2nd continuation
+         yieldk 0 4 
+         cannot be here!
+       ]],
+       [[  # 3th continuation
+          pushvalue 6   # function which is last arg. to 'testC' here
+          pushnum 10; pushnum 20;
+          pcall 2 0 0   # call should throw an error and return to next line
+          pop 1		# remove error message
+          pushvalue 6
+          getglobal status; getglobal ctx
+          pcallk 2 2 5  # call should throw an error and jump to continuation
+          cannot be here!
+       ]],
+       [[  # 4th (and last) continuation
+         return *
+       ]],
+       -- function called by 3th continuation
+       function (a,b) x=a; y=b; error("errmsg") end,
+       ...
+)
+end)
+
+local a = {co(3,4,6)}
+assert(a[1] == 6 and a[2] == undef)
+a = {co()}; assert(a[1] == undef and _G.status == "YIELD" and _G.ctx == 2)
+a = {co()}; assert(a[1] == undef and _G.status == "YIELD" and _G.ctx == 3)
+a = {co(7,8)};
+-- original arguments
+assert(type(a[1]) == 'string' and type(a[2]) == 'string' and
+     type(a[3]) == 'string' and type(a[4]) == 'string' and
+     type(a[5]) == 'string' and type(a[6]) == 'function')
+-- arguments left from fist resume
+assert(a[7] == 3 and a[8] == 4)
+-- arguments to last resume
+assert(a[9] == 7 and a[10] == 8)
+-- error message and nothing more
+assert(a[11]:find("errmsg") and #a == 11)
+-- check arguments to pcallk
+assert(x == "YIELD" and y == 4)
+
+assert(not pcall(co))   -- coroutine should be dead
+
+
+-- bug in nCcalls
+local co = coroutine.wrap(function ()
+  local a = {pcall(pcall,pcall,pcall,pcall,pcall,pcall,pcall,error,"hi")}
+  return pcall(assert, table.unpack(a))
+end)
+
+local a = {co()}
+assert(a[10] == "hi")
+
+print'OK'
diff --git a/test/external/lua-5.4.0-tests/cstack.lua b/test/external/lua-5.4.0-tests/cstack.lua
new file mode 100644
index 0000000..e3e14f7
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/cstack.lua
@@ -0,0 +1,160 @@
+-- $Id: testes/cstack.lua $
+-- See Copyright Notice in file all.lua
+
+local debug = require "debug"
+
+print"testing C-stack overflow detection"
+print"If this test crashes, see its file ('cstack.lua')"
+
+-- Segmentation faults in these tests probably result from a C-stack
+-- overflow. To avoid these errors, you can use the function
+-- 'debug.setcstacklimit' to set a smaller limit for the use of
+-- C stack by Lua. After finding a reliable limit, you might want
+-- to recompile Lua with this limit as the value for
+-- the constant 'LUAI_MAXCCALLS', which defines the default limit.
+-- (The default limit is printed by this test.)
+-- Alternatively, you can ensure a larger stack for the program.
+
+-- For Linux, a limit up to 30_000 seems Ok. Windows cannot go much
+-- higher than 2_000.
+
+
+-- get and print original limit
+local origlimit <const> = debug.setcstacklimit(400)
+print("default stack limit: " .. origlimit)
+
+
+-- Do the tests using the original limit. Or else you may want to change
+-- 'currentlimit' to lower values to avoid a seg. fault or to higher
+-- values to check whether they are reliable.
+local currentlimit <const> =  origlimit
+debug.setcstacklimit(currentlimit)
+print("current stack limit: " .. currentlimit)
+
+
+local function checkerror (msg, f, ...)
+  local s, err = pcall(f, ...)
+  assert(not s and string.find(err, msg))
+end
+
+-- auxiliary function to keep 'count' on the screen even if the program
+-- crashes.
+local count
+local back = string.rep("\b", 8)
+local function progress ()
+  count = count + 1
+  local n = string.format("%-8d", count)
+  io.stderr:write(back, n)   -- erase previous value and write new one
+end
+
+
+do    print("testing simple recursion:")
+  count = 0
+  local function foo ()
+    progress()
+    foo()   -- do recursive calls until a stack error (or crash)
+  end
+  checkerror("stack overflow", foo)
+  print("\tfinal count: ", count)
+end
+
+
+do  print("testing stack overflow in message handling")
+  count = 0
+  local function loop (x, y, z)
+    progress()
+    return 1 + loop(x, y, z)
+  end
+  local res, msg = xpcall(loop, loop)
+  assert(msg == "error in error handling")
+  print("\tfinal count: ", count)
+end
+
+
+-- bug since 2.5 (C-stack overflow in recursion inside pattern matching)
+do  print("testing recursion inside pattern matching")
+  local function f (size)
+    local s = string.rep("a", size)
+    local p = string.rep(".?", size)
+    return string.match(s, p)
+  end
+  local m = f(80)
+  assert(#m == 80)
+  checkerror("too complex", f, 200000)
+end
+
+
+do  print("testing stack-overflow in recursive 'gsub'")
+  count = 0
+  local function foo ()
+    progress()
+    string.gsub("a", ".", foo)
+  end
+  checkerror("stack overflow", foo)
+  print("\tfinal count: ", count)
+
+  print("testing stack-overflow in recursive 'gsub' with metatables")
+  count = 0
+  local t = setmetatable({}, {__index = foo})
+  foo = function ()
+    count = count + 1
+    progress(count)
+    string.gsub("a", ".", t)
+  end
+  checkerror("stack overflow", foo)
+  print("\tfinal count: ", count)
+end
+
+
+do  print("testing changes in C-stack limit")
+
+  -- Just an alternative limit, different from the current one
+  -- (smaller to avoid stack overflows)
+  local alterlimit <const> = currentlimit * 8 // 10
+
+  assert(not debug.setcstacklimit(0))        -- limit too small
+  assert(not debug.setcstacklimit(50000))    -- limit too large
+  local co = coroutine.wrap (function ()
+               return debug.setcstacklimit(alterlimit)
+             end)
+  assert(not co())         -- cannot change C stack inside coroutine
+
+  local n
+  local function foo () n = n + 1; foo () end
+
+  local function check ()
+    n = 0
+    pcall(foo)
+    return n
+  end
+
+  -- set limit to 'alterlimit'
+  assert(debug.setcstacklimit(alterlimit) == currentlimit)
+  local limalter <const> = check()
+  -- set a very low limit (given that there are already several active
+  -- calls to arrive here)
+  local lowlimit <const> = 38
+  assert(debug.setcstacklimit(lowlimit) == alterlimit)
+  -- usable limit is much lower, due to active calls
+  local actuallow = check()
+  assert(actuallow < lowlimit - 30)
+  -- now, add 'lowlimit' extra slots, which should all be available
+  assert(debug.setcstacklimit(lowlimit + lowlimit) == lowlimit)
+  local lim2 <const> = check()
+  assert(lim2 == actuallow + lowlimit)
+
+
+  -- 'setcstacklimit' works inside protected calls. (The new stack
+  -- limit is kept when 'pcall' returns.)
+  assert(pcall(function ()
+    assert(debug.setcstacklimit(alterlimit) == lowlimit * 2)
+    assert(check() <= limalter)
+  end))
+
+  assert(check() == limalter)
+  -- restore original limit
+  assert(debug.setcstacklimit(origlimit) == alterlimit)
+end
+
+
+print'OK'
diff --git a/test/external/lua-5.4.0-tests/db.lua b/test/external/lua-5.4.0-tests/db.lua
new file mode 100644
index 0000000..941283f
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/db.lua
@@ -0,0 +1,963 @@
+-- $Id: testes/db.lua $
+-- See Copyright Notice in file all.lua
+
+-- testing debug library
+
+local debug = require "debug"
+
+local function dostring(s) return assert(load(s))() end
+
+print"testing debug library and debug information"
+
+do
+local a=1
+end
+
+assert(not debug.gethook())
+
+local testline = 19         -- line where 'test' is defined
+function test (s, l, p)     -- this must be line 19
+  collectgarbage()   -- avoid gc during trace
+  local function f (event, line)
+    assert(event == 'line')
+    local l = table.remove(l, 1)
+    if p then print(l, line) end
+    assert(l == line, "wrong trace!!")
+  end
+  debug.sethook(f,"l"); load(s)(); debug.sethook()
+  assert(#l == 0)
+end
+
+
+do
+  assert(not pcall(debug.getinfo, print, "X"))   -- invalid option
+  assert(not debug.getinfo(1000))   -- out of range level
+  assert(not debug.getinfo(-1))     -- out of range level
+  local a = debug.getinfo(print)
+  assert(a.what == "C" and a.short_src == "[C]")
+  a = debug.getinfo(print, "L")
+  assert(a.activelines == nil)
+  local b = debug.getinfo(test, "SfL")
+  assert(b.name == nil and b.what == "Lua" and b.linedefined == testline and
+         b.lastlinedefined == b.linedefined + 10 and
+         b.func == test and not string.find(b.short_src, "%["))
+  assert(b.activelines[b.linedefined + 1] and
+         b.activelines[b.lastlinedefined])
+  assert(not b.activelines[b.linedefined] and
+         not b.activelines[b.lastlinedefined + 1])
+end
+
+
+-- test file and string names truncation
+a = "function f () end"
+local function dostring (s, x) return load(s, x)() end
+dostring(a)
+assert(debug.getinfo(f).short_src == string.format('[string "%s"]', a))
+dostring(a..string.format("; %s\n=1", string.rep('p', 400)))
+assert(string.find(debug.getinfo(f).short_src, '^%[string [^\n]*%.%.%."%]$'))
+dostring(a..string.format("; %s=1", string.rep('p', 400)))
+assert(string.find(debug.getinfo(f).short_src, '^%[string [^\n]*%.%.%."%]$'))
+dostring("\n"..a)
+assert(debug.getinfo(f).short_src == '[string "..."]')
+dostring(a, "")
+assert(debug.getinfo(f).short_src == '[string ""]')
+dostring(a, "@xuxu")
+assert(debug.getinfo(f).short_src == "xuxu")
+dostring(a, "@"..string.rep('p', 1000)..'t')
+assert(string.find(debug.getinfo(f).short_src, "^%.%.%.p*t$"))
+dostring(a, "=xuxu")
+assert(debug.getinfo(f).short_src == "xuxu")
+dostring(a, string.format("=%s", string.rep('x', 500)))
+assert(string.find(debug.getinfo(f).short_src, "^x*$"))
+dostring(a, "=")
+assert(debug.getinfo(f).short_src == "")
+a = nil; f = nil;
+
+
+repeat
+  local g = {x = function ()
+    local a = debug.getinfo(2)
+    assert(a.name == 'f' and a.namewhat == 'local')
+    a = debug.getinfo(1)
+    assert(a.name == 'x' and a.namewhat == 'field')
+    return 'xixi'
+  end}
+  local f = function () return 1+1 and (not 1 or g.x()) end
+  assert(f() == 'xixi')
+  g = debug.getinfo(f)
+  assert(g.what == "Lua" and g.func == f and g.namewhat == "" and not g.name)
+
+  function f (x, name)   -- local!
+    name = name or 'f'
+    local a = debug.getinfo(1)
+    assert(a.name == name and a.namewhat == 'local')
+    return x
+  end
+
+  -- breaks in different conditions
+  if 3>4 then break end; f()
+  if 3<4 then a=1 else break end; f()
+  while 1 do local x=10; break end; f()
+  local b = 1
+  if 3>4 then return math.sin(1) end; f()
+  a = 3<4; f()
+  a = 3<4 or 1; f()
+  repeat local x=20; if 4>3 then f() else break end; f() until 1
+  g = {}
+  f(g).x = f(2) and f(10)+f(9)
+  assert(g.x == f(19))
+  function g(x) if not x then return 3 end return (x('a', 'x')) end
+  assert(g(f) == 'a')
+until 1
+
+test([[if
+math.sin(1)
+then
+  a=1
+else
+  a=2
+end
+]], {2,3,4,7})
+
+test([[--
+if nil then
+  a=1
+else
+  a=2
+end
+]], {2,5,6})
+
+test([[a=1
+repeat
+  a=a+1
+until a==3
+]], {1,3,4,3,4})
+
+test([[ do
+  return
+end
+]], {2})
+
+test([[local a
+a=1
+while a<=3 do
+  a=a+1
+end
+]], {1,2,3,4,3,4,3,4,3,5})
+
+test([[while math.sin(1) do
+  if math.sin(1)
+  then break
+  end
+end
+a=1]], {1,2,3,6})
+
+test([[for i=1,3 do
+  a=i
+end
+]], {1,2,1,2,1,2,1,3})
+
+test([[for i,v in pairs{'a','b'} do
+  a=tostring(i) .. v
+end
+]], {1,2,1,2,1,3})
+
+test([[for i=1,4 do a=1 end]], {1,1,1,1})
+
+
+do   -- testing line info/trace with large gaps in source
+
+  local a = {1, 2, 3, 10, 124, 125, 126, 127, 128, 129, 130,
+             255, 256, 257, 500, 1000}
+  local s = [[
+     local b = {10}
+     a = b[1] X + Y b[1]
+     b = 4
+  ]]
+  for _, i in ipairs(a) do
+    local subs = {X = string.rep("\n", i)}
+    for _, j in ipairs(a) do
+      subs.Y = string.rep("\n", j)
+      local s = string.gsub(s, "[XY]", subs)
+      test(s, {1, 2 + i, 2 + i + j, 2 + i, 2 + i + j, 3 + i + j})
+    end
+  end
+end
+
+print'+'
+
+-- invalid levels in [gs]etlocal
+assert(not pcall(debug.getlocal, 20, 1))
+assert(not pcall(debug.setlocal, -1, 1, 10))
+
+
+-- parameter names
+local function foo (a,b,...) local d, e end
+local co = coroutine.create(foo)
+
+assert(debug.getlocal(foo, 1) == 'a')
+assert(debug.getlocal(foo, 2) == 'b')
+assert(not debug.getlocal(foo, 3))
+assert(debug.getlocal(co, foo, 1) == 'a')
+assert(debug.getlocal(co, foo, 2) == 'b')
+assert(not debug.getlocal(co, foo, 3))
+
+assert(not debug.getlocal(print, 1))
+
+
+local function foo () return (debug.getlocal(1, -1)) end
+assert(not foo(10))
+
+
+-- varargs
+local function foo (a, ...)
+  local t = table.pack(...)
+  for i = 1, t.n do
+    local n, v = debug.getlocal(1, -i)
+    assert(n == "(vararg)" and v == t[i])
+  end
+  assert(not debug.getlocal(1, -(t.n + 1)))
+  assert(not debug.setlocal(1, -(t.n + 1), 30))
+  if t.n > 0 then
+    (function (x)
+      assert(debug.setlocal(2, -1, x) == "(vararg)")
+      assert(debug.setlocal(2, -t.n, x) == "(vararg)")
+     end)(430)
+     assert(... == 430)
+  end
+end
+
+foo()
+foo(print)
+foo(200, 3, 4)
+local a = {}
+for i = 1, (_soft and 100 or 1000) do a[i] = i end
+foo(table.unpack(a))
+a = nil
+
+
+
+do   -- test hook presence in debug info
+  assert(not debug.gethook())
+  local count = 0
+  local function f ()
+    assert(debug.getinfo(1).namewhat == "hook")
+    local sndline = string.match(debug.traceback(), "\n(.-)\n")
+    assert(string.find(sndline, "hook"))
+    count = count + 1
+  end
+  debug.sethook(f, "l")
+  local a = 0
+  _ENV.a = a
+  a = 1
+  debug.sethook()
+  assert(count == 4)
+end
+
+
+-- hook table has weak keys
+assert(getmetatable(debug.getregistry()._HOOKKEY).__mode == 'k')
+
+
+a = {}; L = nil
+local glob = 1
+local oldglob = glob
+debug.sethook(function (e,l)
+  collectgarbage()   -- force GC during a hook
+  local f, m, c = debug.gethook()
+  assert(m == 'crl' and c == 0)
+  if e == "line" then
+    if glob ~= oldglob then
+      L = l-1   -- get the first line where "glob" has changed
+      oldglob = glob
+    end
+  elseif e == "call" then
+      local f = debug.getinfo(2, "f").func
+      a[f] = 1
+  else assert(e == "return")
+  end
+end, "crl")
+
+
+function f(a,b)
+  collectgarbage()
+  local _, x = debug.getlocal(1, 1)
+  local _, y = debug.getlocal(1, 2)
+  assert(x == a and y == b)
+  assert(debug.setlocal(2, 3, "pera") == "AA".."AA")
+  assert(debug.setlocal(2, 4, "maçã") == "B")
+  x = debug.getinfo(2)
+  assert(x.func == g and x.what == "Lua" and x.name == 'g' and
+         x.nups == 2 and string.find(x.source, "^@.*db%.lua$"))
+  glob = glob+1
+  assert(debug.getinfo(1, "l").currentline == L+1)
+  assert(debug.getinfo(1, "l").currentline == L+2)
+end
+
+function foo()
+  glob = glob+1
+  assert(debug.getinfo(1, "l").currentline == L+1)
+end; foo()  -- set L
+-- check line counting inside strings and empty lines
+
+_ = 'alo\
+alo' .. [[
+
+]]
+--[[
+]]
+assert(debug.getinfo(1, "l").currentline == L+11)  -- check count of lines
+
+
+function g (...)
+  local arg = {...}
+  do local a,b,c; a=math.sin(40); end
+  local feijao
+  local AAAA,B = "xuxu", "mamão"
+  f(AAAA,B)
+  assert(AAAA == "pera" and B == "maçã")
+  do
+     local B = 13
+     local x,y = debug.getlocal(1,5)
+     assert(x == 'B' and y == 13)
+  end
+end
+
+g()
+
+
+assert(a[f] and a[g] and a[assert] and a[debug.getlocal] and not a[print])
+
+
+-- tests for manipulating non-registered locals (C and Lua temporaries)
+
+local n, v = debug.getlocal(0, 1)
+assert(v == 0 and n == "(C temporary)")
+local n, v = debug.getlocal(0, 2)
+assert(v == 2 and n == "(C temporary)")
+assert(not debug.getlocal(0, 3))
+assert(not debug.getlocal(0, 0))
+
+function f()
+  assert(select(2, debug.getlocal(2,3)) == 1)
+  assert(not debug.getlocal(2,4))
+  debug.setlocal(2, 3, 10)
+  return 20
+end
+
+function g(a,b) return (a+1) + f() end
+
+assert(g(0,0) == 30)
+ 
+
+debug.sethook(nil);
+assert(not debug.gethook())
+
+
+-- minimal tests for setuservalue/getuservalue
+do
+  assert(not debug.setuservalue(io.stdin, 10))
+  local a, b = debug.getuservalue(io.stdin, 10)
+  assert(a == nil and not b)
+end
+
+-- testing iteraction between multiple values x hooks
+do
+  local function f(...) return 3, ... end
+  local count = 0
+  local a = {}
+  for i = 1, 100 do a[i] = i end
+  debug.sethook(function () count = count + 1 end, "", 1)
+  local t = {table.unpack(a)}
+  assert(#t == 100)
+  t = {table.unpack(a, 1, 3)}
+  assert(#t == 3)
+  t = {f(table.unpack(a, 1, 30))}
+  assert(#t == 31)
+end
+
+
+-- testing access to function arguments
+
+local function collectlocals (level)
+  local tab = {}
+  for i = 1, math.huge do
+    local n, v = debug.getlocal(level + 1, i)
+    if not (n and string.find(n, "^[a-zA-Z0-9_]+$")) then
+       break   -- consider only real variables
+    end
+    tab[n] = v
+  end
+  return tab
+end
+
+
+X = nil
+a = {}
+function a:f (a, b, ...) local arg = {...}; local c = 13 end
+debug.sethook(function (e)
+  assert(e == "call")
+  dostring("XX = 12")  -- test dostring inside hooks
+  -- testing errors inside hooks
+  assert(not pcall(load("a='joao'+1")))
+  debug.sethook(function (e, l) 
+    assert(debug.getinfo(2, "l").currentline == l)
+    local f,m,c = debug.gethook()
+    assert(e == "line")
+    assert(m == 'l' and c == 0)
+    debug.sethook(nil)  -- hook is called only once
+    assert(not X)       -- check that
+    X = collectlocals(2)
+  end, "l")
+end, "c")
+
+a:f(1,2,3,4,5)
+assert(X.self == a and X.a == 1   and X.b == 2 and X.c == nil)
+assert(XX == 12)
+assert(not debug.gethook())
+
+
+-- testing access to local variables in return hook (bug in 5.2)
+do
+  local X = false
+
+  local function foo (a, b, ...)
+    do local x,y,z end
+    local c, d = 10, 20
+    return
+  end
+
+  local function aux ()
+    if debug.getinfo(2).name == "foo" then
+      X = true   -- to signal that it found 'foo'
+      local tab = {a = 100, b = 200, c = 10, d = 20}
+      for n, v in pairs(collectlocals(2)) do
+        assert(tab[n] == v)
+        tab[n] = undef
+      end
+      assert(next(tab) == nil)    -- 'tab' must be empty
+    end
+  end
+
+  debug.sethook(aux, "r"); foo(100, 200); debug.sethook()
+  assert(X)
+
+end
+
+
+local function eqseq (t1, t2)
+  assert(#t1 == #t2)
+  for i = 1, #t1 do
+    assert(t1[i] == t2[i])
+  end
+end
+
+
+do  print("testing inspection of parameters/returned values")
+  local on = false
+  local inp, out
+
+  local function hook (event)
+    if not on then return end
+    local ar = debug.getinfo(2, "ruS")
+    local t = {}
+    for i = ar.ftransfer, ar.ftransfer + ar.ntransfer - 1 do
+      local _, v = debug.getlocal(2, i)
+      t[#t + 1] = v 
+    end
+    if event == "return" then
+      out = t
+    else
+      inp = t
+    end
+  end
+
+  debug.sethook(hook, "cr")
+
+  on = true; math.sin(3); on = false
+  eqseq(inp, {3}); eqseq(out, {math.sin(3)})
+
+  on = true; select(2, 10, 20, 30, 40); on = false
+  eqseq(inp, {2, 10, 20, 30, 40}); eqseq(out, {20, 30, 40})
+
+  local function foo (a, ...) return ... end
+  local function foo1 () on = not on; return foo(20, 10, 0) end
+  foo1(); on = false
+  eqseq(inp, {20}); eqseq(out, {10, 0})
+
+  debug.sethook()
+end
+
+
+
+-- testing upvalue access
+local function getupvalues (f)
+  local t = {}
+  local i = 1
+  while true do
+    local name, value = debug.getupvalue(f, i)
+    if not name then break end
+    assert(not t[name])
+    t[name] = value
+    i = i + 1
+  end
+  return t
+end
+
+local a,b,c = 1,2,3
+local function foo1 (a) b = a; return c end
+local function foo2 (x) a = x; return c+b end
+assert(not debug.getupvalue(foo1, 3))
+assert(not debug.getupvalue(foo1, 0))
+assert(not debug.setupvalue(foo1, 3, "xuxu"))
+local t = getupvalues(foo1)
+assert(t.a == nil and t.b == 2 and t.c == 3)
+t = getupvalues(foo2)
+assert(t.a == 1 and t.b == 2 and t.c == 3)
+assert(debug.setupvalue(foo1, 1, "xuxu") == "b")
+assert(({debug.getupvalue(foo2, 3)})[2] == "xuxu")
+-- upvalues of C functions are allways "called" "" (the empty string)
+assert(debug.getupvalue(string.gmatch("x", "x"), 1) == "")  
+
+
+-- testing count hooks
+local a=0
+debug.sethook(function (e) a=a+1 end, "", 1)
+a=0; for i=1,1000 do end; assert(1000 < a and a < 1012)
+debug.sethook(function (e) a=a+1 end, "", 4)
+a=0; for i=1,1000 do end; assert(250 < a and a < 255)
+local f,m,c = debug.gethook()
+assert(m == "" and c == 4)
+debug.sethook(function (e) a=a+1 end, "", 4000)
+a=0; for i=1,1000 do end; assert(a == 0)
+
+do
+  debug.sethook(print, "", 2^24 - 1)   -- count upperbound
+  local f,m,c = debug.gethook()
+  assert(({debug.gethook()})[3] == 2^24 - 1)
+end
+
+debug.sethook()
+
+
+-- tests for tail calls
+local function f (x)
+  if x then
+    assert(debug.getinfo(1, "S").what == "Lua")
+    assert(debug.getinfo(1, "t").istailcall == true)
+    local tail = debug.getinfo(2)
+    assert(tail.func == g1 and tail.istailcall == true)
+    assert(debug.getinfo(3, "S").what == "main")
+    print"+"
+    end
+end
+
+function g(x) return f(x) end
+
+function g1(x) g(x) end
+
+local function h (x) local f=g1; return f(x) end
+
+h(true)
+
+local b = {}
+debug.sethook(function (e) table.insert(b, e) end, "cr")
+h(false)
+debug.sethook()
+local res = {"return",   -- first return (from sethook)
+  "call", "tail call", "call", "tail call",
+  "return", "return",
+  "call",    -- last call (to sethook)
+}
+for i = 1, #res do assert(res[i] == table.remove(b, 1)) end
+
+b = 0
+debug.sethook(function (e)
+                if e == "tail call" then
+                  b = b + 1
+                  assert(debug.getinfo(2, "t").istailcall == true)
+                else
+                  assert(debug.getinfo(2, "t").istailcall == false)
+                end
+              end, "c")
+h(false)
+debug.sethook()
+assert(b == 2)   -- two tail calls
+
+lim = _soft and 3000 or 30000
+local function foo (x)
+  if x==0 then
+    assert(debug.getinfo(2).what == "main")
+    local info = debug.getinfo(1)
+    assert(info.istailcall == true and info.func == foo)
+  else return foo(x-1)
+  end
+end
+
+foo(lim)
+
+
+print"+"
+
+
+-- testing local function information
+co = load[[
+  local A = function ()
+    return x
+  end
+  return
+]]
+
+local a = 0
+-- 'A' should be visible to debugger only after its complete definition
+debug.sethook(function (e, l)
+  if l == 3 then a = a + 1; assert(debug.getlocal(2, 1) == "(temporary)")
+  elseif l == 4 then a = a + 1; assert(debug.getlocal(2, 1) == "A")
+  end
+end, "l")
+co()  -- run local function definition
+debug.sethook()  -- turn off hook
+assert(a == 2)   -- ensure all two lines where hooked
+
+-- testing traceback
+
+assert(debug.traceback(print) == print)
+assert(debug.traceback(print, 4) == print)
+assert(string.find(debug.traceback("hi", 4), "^hi\n"))
+assert(string.find(debug.traceback("hi"), "^hi\n"))
+assert(not string.find(debug.traceback("hi"), "'debug.traceback'"))
+assert(string.find(debug.traceback("hi", 0), "'debug.traceback'"))
+assert(string.find(debug.traceback(), "^stack traceback:\n"))
+
+do  -- C-function names in traceback
+  local st, msg = (function () return pcall end)()(debug.traceback)
+  assert(st == true and string.find(msg, "pcall"))
+end
+
+
+-- testing nparams, nups e isvararg
+local t = debug.getinfo(print, "u")
+assert(t.isvararg == true and t.nparams == 0 and t.nups == 0)
+
+t = debug.getinfo(function (a,b,c) end, "u")
+assert(t.isvararg == false and t.nparams == 3 and t.nups == 0)
+
+t = debug.getinfo(function (a,b,...) return t[a] end, "u")
+assert(t.isvararg == true and t.nparams == 2 and t.nups == 1)
+
+t = debug.getinfo(1)   -- main
+assert(t.isvararg == true and t.nparams == 0 and t.nups == 1 and
+       debug.getupvalue(t.func, 1) == "_ENV")
+
+t = debug.getinfo(math.sin)   -- C function
+assert(t.isvararg == true and t.nparams == 0 and t.nups == 0)
+
+t = debug.getinfo(string.gmatch("abc", "a"))   -- C closure
+assert(t.isvararg == true and t.nparams == 0 and t.nups > 0)
+
+
+
+-- testing debugging of coroutines
+
+local function checktraceback (co, p, level)
+  local tb = debug.traceback(co, nil, level)
+  local i = 0
+  for l in string.gmatch(tb, "[^\n]+\n?") do
+    assert(i == 0 or string.find(l, p[i]))
+    i = i+1
+  end
+  assert(p[i] == undef)
+end
+
+
+local function f (n)
+  if n > 0 then f(n-1)
+  else coroutine.yield() end
+end
+
+local co = coroutine.create(f)
+coroutine.resume(co, 3)
+checktraceback(co, {"yield", "db.lua", "db.lua", "db.lua", "db.lua"})
+checktraceback(co, {"db.lua", "db.lua", "db.lua", "db.lua"}, 1)
+checktraceback(co, {"db.lua", "db.lua", "db.lua"}, 2)
+checktraceback(co, {"db.lua"}, 4)
+checktraceback(co, {}, 40)
+
+
+co = coroutine.create(function (x)
+       local a = 1
+       coroutine.yield(debug.getinfo(1, "l"))
+       coroutine.yield(debug.getinfo(1, "l").currentline)
+       return a
+     end)
+
+local tr = {}
+local foo = function (e, l) if l then table.insert(tr, l) end end
+debug.sethook(co, foo, "lcr")
+
+local _, l = coroutine.resume(co, 10)
+local x = debug.getinfo(co, 1, "lfLS")
+assert(x.currentline == l.currentline and x.activelines[x.currentline])
+assert(type(x.func) == "function")
+for i=x.linedefined + 1, x.lastlinedefined do
+  assert(x.activelines[i])
+  x.activelines[i] = undef
+end
+assert(next(x.activelines) == nil)   -- no 'extra' elements
+assert(not debug.getinfo(co, 2))
+local a,b = debug.getlocal(co, 1, 1)
+assert(a == "x" and b == 10)
+a,b = debug.getlocal(co, 1, 2)
+assert(a == "a" and b == 1)
+debug.setlocal(co, 1, 2, "hi")
+assert(debug.gethook(co) == foo)
+assert(#tr == 2 and
+       tr[1] == l.currentline-1 and tr[2] == l.currentline)
+
+a,b,c = pcall(coroutine.resume, co)
+assert(a and b and c == l.currentline+1)
+checktraceback(co, {"yield", "in function <"})
+
+a,b = coroutine.resume(co)
+assert(a and b == "hi")
+assert(#tr == 4 and tr[4] == l.currentline+2)
+assert(debug.gethook(co) == foo)
+assert(not debug.gethook())
+checktraceback(co, {})
+
+
+-- check get/setlocal in coroutines
+co = coroutine.create(function (x)
+  local a, b = coroutine.yield(x)
+  assert(a == 100 and b == nil)
+  return x
+end)
+a, b = coroutine.resume(co, 10)
+assert(a and b == 10)
+a, b = debug.getlocal(co, 1, 1)
+assert(a == "x" and b == 10)
+assert(not debug.getlocal(co, 1, 5))
+assert(debug.setlocal(co, 1, 1, 30) == "x")
+assert(not debug.setlocal(co, 1, 5, 40))
+a, b = coroutine.resume(co, 100)
+assert(a and b == 30)
+
+
+-- check traceback of suspended (or dead with error) coroutines
+
+function f(i)
+  if i == 0 then error(i)
+  else coroutine.yield(); f(i-1)
+  end
+end
+
+
+co = coroutine.create(function (x) f(x) end)
+a, b = coroutine.resume(co, 3)
+t = {"'coroutine.yield'", "'f'", "in function <"}
+while coroutine.status(co) == "suspended" do
+  checktraceback(co, t)
+  a, b = coroutine.resume(co)
+  table.insert(t, 2, "'f'")   -- one more recursive call to 'f'
+end
+t[1] = "'error'"
+checktraceback(co, t)
+
+
+-- test acessing line numbers of a coroutine from a resume inside
+-- a C function (this is a known bug in Lua 5.0)
+
+local function g(x)
+    coroutine.yield(x)
+end
+
+local function f (i)
+  debug.sethook(function () end, "l")
+  for j=1,1000 do
+    g(i+j)
+  end
+end
+
+local co = coroutine.wrap(f)
+co(10)
+pcall(co)
+pcall(co)
+
+
+assert(type(debug.getregistry()) == "table")
+
+
+-- test tagmethod information
+local a = {}
+local function f (t)
+  local info = debug.getinfo(1);
+  assert(info.namewhat == "metamethod")
+  a.op = info.name
+  return info.name
+end
+setmetatable(a, {
+  __index = f; __add = f; __div = f; __mod = f; __concat = f; __pow = f;
+  __mul = f; __idiv = f; __unm = f; __len = f; __sub = f;
+  __shl = f; __shr = f; __bor = f; __bxor = f;
+  __eq = f; __le = f; __lt = f; __unm = f; __len = f; __band = f;
+  __bnot = f;
+})
+
+local b = setmetatable({}, getmetatable(a))
+
+assert(a[3] == "index" and a^3 == "pow" and a..a == "concat")
+assert(a/3 == "div" and 3%a == "mod")
+assert(a+3 == "add" and 3-a == "sub" and a*3 == "mul" and
+       -a == "unm" and #a == "len" and a&3 == "band")
+assert(a + 30000 == "add" and a - 3.0 == "sub" and a * 3.0 == "mul" and
+       -a == "unm" and #a == "len" and a & 3 == "band")
+assert(a|3 == "bor" and 3~a == "bxor" and a<<3 == "shl" and a>>1 == "shr")
+assert (a==b and a.op == "eq")
+assert (a>=b and a.op == "order")
+assert (a>b and a.op == "order")
+assert(~a == "bnot")
+
+do   -- testing for-iterator name
+  local function f()
+    assert(debug.getinfo(1).name == "for iterator")
+  end
+
+  for i in f do end
+end
+
+
+do   -- testing debug info for finalizers
+  local name = nil
+
+  -- create a piece of garbage with a finalizer
+  setmetatable({}, {__gc = function ()
+    local t = debug.getinfo(2)   -- get callee information
+    assert(t.namewhat == "metamethod")
+    name = t.name
+  end})
+
+  -- repeat until previous finalizer runs (setting 'name')
+  repeat local a = {} until name
+  assert(name == "__gc")
+end
+
+
+do
+  print("testing traceback sizes")
+
+  local function countlines (s)
+    return select(2, string.gsub(s, "\n", ""))
+  end
+
+  local function deep (lvl, n)
+    if lvl == 0 then
+      return (debug.traceback("message", n))
+    else
+      return (deep(lvl-1, n))
+    end
+  end
+
+  local function checkdeep (total, start)
+    local s = deep(total, start)
+    local rest = string.match(s, "^message\nstack traceback:\n(.*)$")
+    local cl = countlines(rest)
+    -- at most 10 lines in first part, 11 in second, plus '...'
+    assert(cl <= 10 + 11 + 1)
+    local brk = string.find(rest, "%.%.%.")
+    if brk then   -- does message have '...'?
+      local rest1 = string.sub(rest, 1, brk)
+      local rest2 = string.sub(rest, brk, #rest)
+      assert(countlines(rest1) == 10 and countlines(rest2) == 11)
+    else
+      assert(cl == total - start + 2)
+    end
+  end
+
+  for d = 1, 51, 10 do
+    for l = 1, d do
+      -- use coroutines to ensure complete control of the stack
+      coroutine.wrap(checkdeep)(d, l)
+    end
+  end
+
+end
+
+
+print("testing debug functions on chunk without debug info")
+prog = [[-- program to be loaded without debug information
+local debug = require'debug'
+local a = 12  -- a local variable
+
+local n, v = debug.getlocal(1, 1)
+assert(n == "(temporary)" and v == debug)   -- unkown name but known value
+n, v = debug.getlocal(1, 2)
+assert(n == "(temporary)" and v == 12)   -- unkown name but known value
+
+-- a function with an upvalue
+local f = function () local x; return a end
+n, v = debug.getupvalue(f, 1)
+assert(n == "(no name)" and v == 12)
+assert(debug.setupvalue(f, 1, 13) == "(no name)")
+assert(a == 13)
+
+local t = debug.getinfo(f)
+assert(t.name == nil and t.linedefined > 0 and
+       t.lastlinedefined == t.linedefined and
+       t.short_src == "?")
+assert(debug.getinfo(1).currentline == -1)
+
+t = debug.getinfo(f, "L").activelines
+assert(next(t) == nil)    -- active lines are empty
+
+-- dump/load a function without debug info
+f = load(string.dump(f))
+
+t = debug.getinfo(f)
+assert(t.name == nil and t.linedefined > 0 and
+       t.lastlinedefined == t.linedefined and
+       t.short_src == "?")
+assert(debug.getinfo(1).currentline == -1)
+
+return a
+]]
+
+
+-- load 'prog' without debug info
+local f = assert(load(string.dump(load(prog), true)))
+
+assert(f() == 13)
+
+do   -- tests for 'source' in binary dumps
+  local prog = [[
+    return function (x)
+      return function (y) 
+        return x + y
+      end
+    end
+  ]]
+  local name = string.rep("x", 1000)
+  local p = assert(load(prog, name))
+  -- load 'p' as a binary chunk with debug information
+  local c = string.dump(p)
+  assert(#c > 1000 and #c < 2000)   -- no repetition of 'source' in dump
+  local f = assert(load(c))
+  local g = f()
+  local h = g(3)
+  assert(h(5) == 8)
+  assert(debug.getinfo(f).source == name and   -- all functions have 'source'
+         debug.getinfo(g).source == name and 
+         debug.getinfo(h).source == name)
+  -- again, without debug info
+  local c = string.dump(p, true)
+  assert(#c < 500)   -- no 'source' in dump
+  local f = assert(load(c))
+  local g = f()
+  local h = g(30)
+  assert(h(50) == 80)
+  assert(debug.getinfo(f).source == '=?' and   -- no function has 'source'
+         debug.getinfo(g).source == '=?' and 
+         debug.getinfo(h).source == '=?')
+end
+
+print"OK"
+
diff --git a/test/external/lua-5.4.0-tests/errors.lua b/test/external/lua-5.4.0-tests/errors.lua
new file mode 100644
index 0000000..f9623b1
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/errors.lua
@@ -0,0 +1,589 @@
+-- $Id: testes/errors.lua $
+-- See Copyright Notice in file all.lua
+
+print("testing errors")
+
+local debug = require"debug"
+
+-- avoid problems with 'strict' module (which may generate other error messages)
+local mt = getmetatable(_G) or {}
+local oldmm = mt.__index
+mt.__index = nil
+
+local function checkerr (msg, f, ...)
+  local st, err = pcall(f, ...)
+  assert(not st and string.find(err, msg))
+end
+
+
+local function doit (s)
+  local f, msg = load(s)
+  if not f then return msg end
+  local cond, msg = pcall(f)
+  return (not cond) and msg
+end
+
+
+local function checkmessage (prog, msg)
+  local m = doit(prog)
+  assert(string.find(m, msg, 1, true))
+end
+
+local function checksyntax (prog, extra, token, line)
+  local msg = doit(prog)
+  if not string.find(token, "^<%a") and not string.find(token, "^char%(")
+    then token = "'"..token.."'" end
+  token = string.gsub(token, "(%p)", "%%%1")
+  local pt = string.format([[^%%[string ".*"%%]:%d: .- near %s$]],
+                           line, token)
+  assert(string.find(msg, pt))
+  assert(string.find(msg, msg, 1, true))
+end
+
+
+-- test error message with no extra info
+assert(doit("error('hi', 0)") == 'hi')
+
+-- test error message with no info
+assert(doit("error()") == nil)
+
+
+-- test common errors/errors that crashed in the past
+assert(doit("table.unpack({}, 1, n=2^30)"))
+assert(doit("a=math.sin()"))
+assert(not doit("tostring(1)") and doit("tostring()"))
+assert(doit"tonumber()")
+assert(doit"repeat until 1; a")
+assert(doit"return;;")
+assert(doit"assert(false)")
+assert(doit"assert(nil)")
+assert(doit("function a (... , ...) end"))
+assert(doit("function a (, ...) end"))
+assert(doit("local t={}; t = t[#t] + 1"))
+
+checksyntax([[
+  local a = {4
+
+]], "'}' expected (to close '{' at line 1)", "<eof>", 3)
+
+
+if not T then
+  (Message or print)
+    ('\n >>> testC not active: skipping memory message test <<<\n')
+else
+  print "testing memory error message"
+  local a = {}
+  for i = 1, 10000 do a[i] = true end   -- preallocate array
+  collectgarbage()
+  T.totalmem(T.totalmem() + 10000)
+  -- force a memory error (by a small margin)
+  local st, msg = pcall(function()
+    for i = 1, 100000 do a[i] = tostring(i) end
+  end)
+  T.totalmem(0)
+  assert(not st and msg == "not enough" .. " memory")
+end
+
+
+-- tests for better error messages
+
+checkmessage("a = {} + 1", "arithmetic")
+checkmessage("a = {} | 1", "bitwise operation")
+checkmessage("a = {} < 1", "attempt to compare")
+checkmessage("a = {} <= 1", "attempt to compare")
+
+checkmessage("a=1; bbbb=2; a=math.sin(3)+bbbb(3)", "global 'bbbb'")
+checkmessage("a={}; do local a=1 end a:bbbb(3)", "method 'bbbb'")
+checkmessage("local a={}; a.bbbb(3)", "field 'bbbb'")
+assert(not string.find(doit"a={13}; local bbbb=1; a[bbbb](3)", "'bbbb'"))
+checkmessage("a={13}; local bbbb=1; a[bbbb](3)", "number")
+checkmessage("a=(1)..{}", "a table value")
+
+-- tail calls
+checkmessage("local a={}; return a.bbbb(3)", "field 'bbbb'")
+checkmessage("a={}; do local a=1 end; return a:bbbb(3)", "method 'bbbb'")
+
+checkmessage("a = #print", "length of a function value")
+checkmessage("a = #3", "length of a number value")
+
+aaa = nil
+checkmessage("aaa.bbb:ddd(9)", "global 'aaa'")
+checkmessage("local aaa={bbb=1}; aaa.bbb:ddd(9)", "field 'bbb'")
+checkmessage("local aaa={bbb={}}; aaa.bbb:ddd(9)", "method 'ddd'")
+checkmessage("local a,b,c; (function () a = b+1.1 end)()", "upvalue 'b'")
+assert(not doit"local aaa={bbb={ddd=next}}; aaa.bbb:ddd(nil)")
+
+-- upvalues being indexed do not go to the stack
+checkmessage("local a,b,cc; (function () a = cc[1] end)()", "upvalue 'cc'")
+checkmessage("local a,b,cc; (function () a.x = 1 end)()", "upvalue 'a'")
+
+checkmessage("local _ENV = {x={}}; a = a + 1", "global 'a'")
+
+checkmessage("b=1; local aaa={}; x=aaa+b", "local 'aaa'")
+checkmessage("aaa={}; x=3.3/aaa", "global 'aaa'")
+checkmessage("aaa=2; b=nil;x=aaa*b", "global 'b'")
+checkmessage("aaa={}; x=-aaa", "global 'aaa'")
+
+-- short circuit
+checkmessage("a=1; local a,bbbb=2,3; a = math.sin(1) and bbbb(3)",
+       "local 'bbbb'")
+checkmessage("a=1; local a,bbbb=2,3; a = bbbb(1) or a(3)", "local 'bbbb'")
+checkmessage("local a,b,c,f = 1,1,1; f((a and b) or c)", "local 'f'")
+checkmessage("local a,b,c = 1,1,1; ((a and b) or c)()", "call a number value")
+assert(not string.find(doit"aaa={}; x=(aaa or aaa)+(aaa and aaa)", "'aaa'"))
+assert(not string.find(doit"aaa={}; (aaa or aaa)()", "'aaa'"))
+
+checkmessage("print(print < 10)", "function with number")
+checkmessage("print(print < print)", "two function values")
+checkmessage("print('10' < 10)", "string with number")
+checkmessage("print(10 < '23')", "number with string")
+
+-- float->integer conversions
+checkmessage("local a = 2.0^100; x = a << 2", "local a")
+checkmessage("local a = 1 >> 2.0^100", "has no integer representation")
+checkmessage("local a = 10.1 << 2.0^100", "has no integer representation")
+checkmessage("local a = 2.0^100 & 1", "has no integer representation")
+checkmessage("local a = 2.0^100 & 1e100", "has no integer representation")
+checkmessage("local a = 2.0 | 1e40", "has no integer representation")
+checkmessage("local a = 2e100 ~ 1", "has no integer representation")
+checkmessage("string.sub('a', 2.0^100)", "has no integer representation")
+checkmessage("string.rep('a', 3.3)", "has no integer representation")
+checkmessage("return 6e40 & 7", "has no integer representation")
+checkmessage("return 34 << 7e30", "has no integer representation")
+checkmessage("return ~-3e40", "has no integer representation")
+checkmessage("return ~-3.009", "has no integer representation")
+checkmessage("return 3.009 & 1", "has no integer representation")
+checkmessage("return 34 >> {}", "table value")
+checkmessage("a = 24 // 0", "divide by zero")
+checkmessage("a = 1 % 0", "'n%0'")
+
+
+-- numeric for loops
+checkmessage("for i = {}, 10 do end", "table")
+checkmessage("for i = io.stdin, 10 do end", "FILE")
+checkmessage("for i = {}, 10 do end", "initial value")
+checkmessage("for i = 1, 'x', 10 do end", "string")
+checkmessage("for i = 1, {}, 10 do end", "limit")
+checkmessage("for i = 1, {} do end", "limit")
+checkmessage("for i = 1, 10, print do end", "step")
+checkmessage("for i = 1, 10, print do end", "function")
+
+-- passing light userdata instead of full userdata
+_G.D = debug
+checkmessage([[
+  -- create light udata
+  local x = D.upvalueid(function () return debug end, 1)
+  D.setuservalue(x, {})
+]], "light userdata")
+_G.D = nil
+
+do   -- named objects (field '__name')
+  checkmessage("math.sin(io.input())", "(number expected, got FILE*)")
+  _G.XX = setmetatable({}, {__name = "My Type"})
+  assert(string.find(tostring(XX), "^My Type"))
+  checkmessage("io.input(XX)", "(FILE* expected, got My Type)")
+  checkmessage("return XX + 1", "on a My Type value")
+  checkmessage("return ~io.stdin", "on a FILE* value")
+  checkmessage("return XX < XX", "two My Type values")
+  checkmessage("return {} < XX", "table with My Type")
+  checkmessage("return XX < io.stdin", "My Type with FILE*")
+  _G.XX = nil
+end
+
+-- global functions
+checkmessage("(io.write or print){}", "io.write")
+checkmessage("(collectgarbage or print){}", "collectgarbage")
+
+-- errors in functions without debug info
+do
+  local f = function (a) return a + 1 end
+  f = assert(load(string.dump(f, true)))
+  assert(f(3) == 4)
+  checkerr("^%?:%-1:", f, {})
+
+  -- code with a move to a local var ('OP_MOV A B' with A<B)
+  f = function () local a; a = {}; return a + 2 end
+  -- no debug info (so that 'a' is unknown)
+  f = assert(load(string.dump(f, true)))
+  -- symbolic execution should not get lost
+  checkerr("^%?:%-1:.*table value", f)
+end
+
+
+-- tests for field accesses after RK limit
+local t = {}
+for i = 1, 1000 do
+  t[i] = "a = x" .. i
+end
+local s = table.concat(t, "; ")
+t = nil
+checkmessage(s.."; a = bbb + 1", "global 'bbb'")
+checkmessage("local _ENV=_ENV;"..s.."; a = bbb + 1", "global 'bbb'")
+checkmessage(s.."; local t = {}; a = t.bbb + 1", "field 'bbb'")
+checkmessage(s.."; local t = {}; t:bbb()", "method 'bbb'")
+
+checkmessage([[aaa=9
+repeat until 3==3
+local x=math.sin(math.cos(3))
+if math.sin(1) == x then return math.sin(1) end   -- tail call
+local a,b = 1, {
+  {x='a'..'b'..'c', y='b', z=x},
+  {1,2,3,4,5} or 3+3<=3+3,
+  3+1>3+1,
+  {d = x and aaa[x or y]}}
+]], "global 'aaa'")
+
+checkmessage([[
+local x,y = {},1
+if math.sin(1) == 0 then return 3 end    -- return
+x.a()]], "field 'a'")
+
+checkmessage([[
+prefix = nil
+insert = nil
+while 1 do
+  local a
+  if nil then break end
+  insert(prefix, a)
+end]], "global 'insert'")
+
+checkmessage([[  -- tail call
+  return math.sin("a")
+]], "'sin'")
+
+checkmessage([[collectgarbage("nooption")]], "invalid option")
+
+checkmessage([[x = print .. "a"]], "concatenate")
+checkmessage([[x = "a" .. false]], "concatenate")
+checkmessage([[x = {} .. 2]], "concatenate")
+
+checkmessage("getmetatable(io.stdin).__gc()", "no value")
+
+checkmessage([[
+local Var
+local function main()
+  NoSuchName (function() Var=0 end)
+end
+main()
+]], "global 'NoSuchName'")
+print'+'
+
+a = {}; setmetatable(a, {__index = string})
+checkmessage("a:sub()", "bad self")
+checkmessage("string.sub('a', {})", "#2")
+checkmessage("('a'):sub{}", "#1")
+
+checkmessage("table.sort({1,2,3}, table.sort)", "'table.sort'")
+checkmessage("string.gsub('s', 's', setmetatable)", "'setmetatable'")
+
+-- tests for errors in coroutines
+
+local function f (n)
+  local c = coroutine.create(f)
+  local a,b = coroutine.resume(c)
+  return b
+end
+assert(string.find(f(), "C stack overflow"))
+
+checkmessage("coroutine.yield()", "outside a coroutine")
+
+f = coroutine.wrap(function () table.sort({1,2,3}, coroutine.yield) end)
+checkerr("yield across", f)
+
+
+-- testing size of 'source' info; size of buffer for that info is
+-- LUA_IDSIZE, declared as 60 in luaconf. Get one position for '\0'.
+idsize = 60 - 1
+local function checksize (source)
+  -- syntax error
+  local _, msg = load("x", source)
+  msg = string.match(msg, "^([^:]*):")   -- get source (1st part before ':')
+  assert(msg:len() <= idsize)
+end
+
+for i = 60 - 10, 60 + 10 do   -- check border cases around 60
+  checksize("@" .. string.rep("x", i))   -- file names
+  checksize(string.rep("x", i - 10))     -- string sources
+  checksize("=" .. string.rep("x", i))   -- exact sources
+end
+
+
+-- testing line error
+
+local function lineerror (s, l)
+  local err,msg = pcall(load(s))
+  local line = tonumber(string.match(msg, ":(%d+):"))
+  assert(line == l or (not line and not l))
+end
+
+lineerror("local a\n for i=1,'a' do \n print(i) \n end", 2)
+lineerror("\n local a \n for k,v in 3 \n do \n print(k) \n end", 3)
+lineerror("\n\n for k,v in \n 3 \n do \n print(k) \n end", 4)
+lineerror("function a.x.y ()\na=a+1\nend", 1)
+
+lineerror("a = \na\n+\n{}", 3)
+lineerror("a = \n3\n+\n(\n4\n/\nprint)", 6)
+lineerror("a = \nprint\n+\n(\n4\n/\n7)", 3)
+
+lineerror("a\n=\n-\n\nprint\n;", 3)
+
+lineerror([[
+a
+(
+23)
+]], 1)
+
+lineerror([[
+local a = {x = 13}
+a
+.
+x
+(
+23
+)
+]], 2)
+
+lineerror([[
+local a = {x = 13}
+a
+.
+x
+(
+23 + a
+)
+]], 6)
+
+local p = [[
+  function g() f() end
+  function f(x) error('a', X) end
+g()
+]]
+X=3;lineerror((p), 3)
+X=0;lineerror((p), false)
+X=1;lineerror((p), 2)
+X=2;lineerror((p), 1)
+
+
+lineerror([[
+local b = false
+if not b then
+  error 'test'
+end]], 3)
+
+lineerror([[
+local b = false
+if not b then
+  if not b then
+    if not b then
+      error 'test'
+    end
+  end
+end]], 5)
+
+
+if not _soft then
+  -- several tests that exaust the Lua stack
+  collectgarbage()
+  print"testing stack overflow"
+  C = 0
+  local l = debug.getinfo(1, "l").currentline; function y () C=C+1; y() end
+
+  local function checkstackmessage (m)
+    return (string.find(m, "stack overflow"))
+  end
+  -- repeated stack overflows (to check stack recovery)
+  assert(checkstackmessage(doit('y()')))
+  print('+')
+  assert(checkstackmessage(doit('y()')))
+  print('+')
+  assert(checkstackmessage(doit('y()')))
+  print('+')
+
+
+  -- error lines in stack overflow
+  C = 0
+  local l1
+  local function g(x)
+    l1 = debug.getinfo(x, "l").currentline; y()
+  end
+  local _, stackmsg = xpcall(g, debug.traceback, 1)
+  print('+')
+  local stack = {}
+  for line in string.gmatch(stackmsg, "[^\n]*") do
+    local curr = string.match(line, ":(%d+):")
+    if curr then table.insert(stack, tonumber(curr)) end
+  end
+  local i=1
+  while stack[i] ~= l1 do
+    assert(stack[i] == l)
+    i = i+1
+  end
+  assert(i > 15)
+
+
+  -- error in error handling
+  local res, msg = xpcall(error, error)
+  assert(not res and type(msg) == 'string')
+  print('+')
+
+  local function f (x)
+    if x==0 then error('a\n')
+    else
+      local aux = function () return f(x-1) end
+      local a,b = xpcall(aux, aux)
+      return a,b
+    end
+  end
+  f(3)
+
+  local function loop (x,y,z) return 1 + loop(x, y, z) end
+ 
+  local res, msg = xpcall(loop, function (m)
+    assert(string.find(m, "stack overflow"))
+    checkerr("error handling", loop)
+    assert(math.sin(0) == 0)
+    return 15
+  end)
+  assert(msg == 15)
+
+  local f = function ()
+    for i = 999900, 1000000, 1 do table.unpack({}, 1, i) end
+  end
+  checkerr("too many results", f)
+
+end
+
+
+do
+  -- non string messages
+  local t = {}
+  local res, msg = pcall(function () error(t) end)
+  assert(not res and msg == t)
+
+  res, msg = pcall(function () error(nil) end)
+  assert(not res and msg == nil)
+
+  local function f() error{msg='x'} end
+  res, msg = xpcall(f, function (r) return {msg=r.msg..'y'} end)
+  assert(msg.msg == 'xy')
+
+  -- 'assert' with extra arguments
+  res, msg = pcall(assert, false, "X", t)
+  assert(not res and msg == "X")
+ 
+  -- 'assert' with no message
+  res, msg = pcall(function () assert(false) end)
+  local line = string.match(msg, "%w+%.lua:(%d+): assertion failed!$")
+  assert(tonumber(line) == debug.getinfo(1, "l").currentline - 2)
+
+  -- 'assert' with non-string messages
+  res, msg = pcall(assert, false, t)
+  assert(not res and msg == t)
+
+  res, msg = pcall(assert, nil, nil)
+  assert(not res and msg == nil)
+
+  -- 'assert' without arguments
+  res, msg = pcall(assert)
+  assert(not res and string.find(msg, "value expected"))
+end
+
+-- xpcall with arguments
+a, b, c = xpcall(string.find, error, "alo", "al")
+assert(a and b == 1 and c == 2)
+a, b, c = xpcall(string.find, function (x) return {} end, true, "al")
+assert(not a and type(b) == "table" and c == nil)
+
+
+print("testing tokens in error messages")
+checksyntax("syntax error", "", "error", 1)
+checksyntax("1.000", "", "1.000", 1)
+checksyntax("[[a]]", "", "[[a]]", 1)
+checksyntax("'aa'", "", "'aa'", 1)
+checksyntax("while << do end", "", "<<", 1)
+checksyntax("for >> do end", "", ">>", 1)
+
+-- test invalid non-printable char in a chunk
+checksyntax("a\1a = 1", "", "<\\1>", 1)
+
+-- test 255 as first char in a chunk
+checksyntax("\255a = 1", "", "<\\255>", 1)
+
+doit('I = load("a=9+"); a=3')
+assert(a==3 and not I)
+print('+')
+
+lim = 1000
+if _soft then lim = 100 end
+for i=1,lim do
+  doit('a = ')
+  doit('a = 4+nil')
+end
+
+
+-- testing syntax limits
+
+local function testrep (init, rep, close, repc, finalresult)
+  local s = init .. string.rep(rep, 100) .. close .. string.rep(repc, 100)
+  local res, msg = load(s)
+  assert(res)   -- 100 levels is OK
+  if (finalresult) then
+    assert(res() == finalresult)
+  end
+  s = init .. string.rep(rep, 10000)
+  local res, msg = load(s)   -- 10000 levels not ok
+  assert(not res and (string.find(msg, "too many registers") or
+                      string.find(msg, "stack overflow")))
+end
+
+testrep("local a; a", ",a", "= 1", ",1")    -- multiple assignment
+testrep("local a; a=", "{", "0", "}")
+testrep("return ", "(", "2", ")", 2)
+testrep("local function a (x) return x end; return ", "a(", "2.2", ")", 2.2)
+testrep("", "do ", "", " end")
+testrep("", "while a do ", "", " end")
+testrep("local a; ", "if a then else ", "", " end")
+testrep("", "function foo () ", "", " end")
+testrep("local a = ''; return ", "a..", "'a'", "", "a")
+testrep("local a = 1; return ", "a^", "a", "", 1)
+
+checkmessage("a = f(x" .. string.rep(",x", 260) .. ")", "too many registers")
+
+
+-- testing other limits
+
+-- upvalues
+local lim = 127
+local  s = "local function fooA ()\n  local "
+for j = 1,lim do
+  s = s.."a"..j..", "
+end
+s = s.."b,c\n"
+s = s.."local function fooB ()\n  local "
+for j = 1,lim do
+  s = s.."b"..j..", "
+end
+s = s.."b\n"
+s = s.."function fooC () return b+c"
+local c = 1+2
+for j = 1,lim do
+  s = s.."+a"..j.."+b"..j
+  c = c + 2
+end
+s = s.."\nend  end end"
+local a,b = load(s)
+assert(c > 255 and string.find(b, "too many upvalues") and
+       string.find(b, "line 5"))
+
+-- local variables
+s = "\nfunction foo ()\n  local "
+for j = 1,300 do
+  s = s.."a"..j..", "
+end
+s = s.."b\n"
+local a,b = load(s)
+assert(string.find(b, "line 2") and string.find(b, "too many local variables"))
+
+mt.__index = oldmm
+
+print('OK')
diff --git a/test/external/lua-5.4.0-tests/events.lua b/test/external/lua-5.4.0-tests/events.lua
new file mode 100644
index 0000000..8a01330
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/events.lua
@@ -0,0 +1,477 @@
+-- $Id: testes/events.lua $
+-- See Copyright Notice in file all.lua
+
+print('testing metatables')
+
+local debug = require'debug'
+
+X = 20; B = 30
+
+_ENV = setmetatable({}, {__index=_G})
+
+collectgarbage()
+
+X = X+10
+assert(X == 30 and _G.X == 20)
+B = false
+assert(B == false)
+_ENV["B"] = undef
+assert(B == 30)
+
+assert(getmetatable{} == nil)
+assert(getmetatable(4) == nil)
+assert(getmetatable(nil) == nil)
+a={name = "NAME"}; setmetatable(a, {__metatable = "xuxu",
+                    __tostring=function(x) return x.name end})
+assert(getmetatable(a) == "xuxu")
+assert(tostring(a) == "NAME")
+-- cannot change a protected metatable
+assert(pcall(setmetatable, a, {}) == false)
+a.name = "gororoba"
+assert(tostring(a) == "gororoba")
+
+local a, t = {10,20,30; x="10", y="20"}, {}
+assert(setmetatable(a,t) == a)
+assert(getmetatable(a) == t)
+assert(setmetatable(a,nil) == a)
+assert(getmetatable(a) == nil)
+assert(setmetatable(a,t) == a)
+
+
+function f (t, i, e)
+  assert(not e)
+  local p = rawget(t, "parent")
+  return (p and p[i]+3), "dummy return"
+end
+
+t.__index = f
+
+a.parent = {z=25, x=12, [4] = 24}
+assert(a[1] == 10 and a.z == 28 and a[4] == 27 and a.x == "10")
+
+collectgarbage()
+
+a = setmetatable({}, t)
+function f(t, i, v) rawset(t, i, v-3) end
+setmetatable(t, t)   -- causes a bug in 5.1 !
+t.__newindex = f
+a[1] = 30; a.x = "101"; a[5] = 200
+assert(a[1] == 27 and a.x == 98 and a[5] == 197)
+
+do    -- bug in Lua 5.3.2
+  local mt = {}
+  mt.__newindex = mt
+  local t = setmetatable({}, mt)
+  t[1] = 10     -- will segfault on some machines
+  assert(mt[1] == 10)
+end
+
+
+local c = {}
+a = setmetatable({}, t)
+t.__newindex = c
+t.__index = c
+a[1] = 10; a[2] = 20; a[3] = 90;
+for i = 4, 20 do a[i] = i * 10 end
+assert(a[1] == 10 and a[2] == 20 and a[3] == 90)
+for i = 4, 20 do assert(a[i] == i * 10) end
+assert(next(a) == nil)
+
+
+do
+  local a;
+  a = setmetatable({}, {__index = setmetatable({},
+                     {__index = setmetatable({},
+                     {__index = function (_,n) return a[n-3]+4, "lixo" end})})})
+  a[0] = 20
+  for i=0,10 do
+    assert(a[i*3] == 20 + i*4)
+  end
+end
+
+
+do  -- newindex
+  local foi
+  local a = {}
+  for i=1,10 do a[i] = 0; a['a'..i] = 0; end
+  setmetatable(a, {__newindex = function (t,k,v) foi=true; rawset(t,k,v) end})
+  foi = false; a[1]=0; assert(not foi)
+  foi = false; a['a1']=0; assert(not foi)
+  foi = false; a['a11']=0; assert(foi)
+  foi = false; a[11]=0; assert(foi)
+  foi = false; a[1]=undef; assert(not foi)
+  a[1] = undef
+  foi = false; a[1]=nil; assert(foi)
+end
+
+
+setmetatable(t, nil)
+function f (t, ...) return t, {...} end
+t.__call = f
+
+do
+  local x,y = a(table.unpack{'a', 1})
+  assert(x==a and y[1]=='a' and y[2]==1 and y[3]==undef)
+  x,y = a()
+  assert(x==a and y[1]==undef)
+end
+
+
+local b = setmetatable({}, t)
+setmetatable(b,t)
+
+function f(op)
+  return function (...) cap = {[0] = op, ...} ; return (...) end
+end
+t.__add = f("add")
+t.__sub = f("sub")
+t.__mul = f("mul")
+t.__div = f("div")
+t.__idiv = f("idiv")
+t.__mod = f("mod")
+t.__unm = f("unm")
+t.__pow = f("pow")
+t.__len = f("len")
+t.__band = f("band")
+t.__bor = f("bor")
+t.__bxor = f("bxor")
+t.__shl = f("shl")
+t.__shr = f("shr")
+t.__bnot = f("bnot")
+t.__lt = f("lt")
+t.__le = f("le")
+
+
+local function checkcap (t)
+  assert(#cap + 1 == #t)
+  for i = 1, #t do
+    assert(cap[i - 1] == t[i])
+    assert(math.type(cap[i - 1]) == math.type(t[i]))
+  end
+end
+
+-- Some tests are done inside small anonymous functions to ensure
+-- that constants go to constant table even in debug compilation,
+-- when the constant table is very small.
+assert(b+5 == b); checkcap{"add", b, 5}
+assert(5.2 + b == 5.2); checkcap{"add", 5.2, b}
+assert(b+'5' == b); checkcap{"add", b, '5'}
+assert(5+b == 5); checkcap{"add", 5, b}
+assert('5'+b == '5'); checkcap{"add", '5', b}
+b=b-3; assert(getmetatable(b) == t); checkcap{"sub", b, 3}
+assert(5-a == 5); checkcap{"sub", 5, a}
+assert('5'-a == '5'); checkcap{"sub", '5', a}
+assert(a*a == a); checkcap{"mul", a, a}
+assert(a/0 == a); checkcap{"div", a, 0}
+assert(a/0.0 == a); checkcap{"div", a, 0.0}
+assert(a%2 == a); checkcap{"mod", a, 2}
+assert(a // (1/0) == a); checkcap{"idiv", a, 1/0}
+;(function () assert(a & "hi" == a) end)(); checkcap{"band", a, "hi"}
+;(function () assert(10 & a  == 10) end)(); checkcap{"band", 10, a}
+;(function () assert(a | 10  == a) end)(); checkcap{"bor", a, 10}
+assert(a | "hi" == a); checkcap{"bor", a, "hi"}
+assert("hi" ~ a == "hi"); checkcap{"bxor", "hi", a}
+;(function () assert(10 ~ a == 10) end)(); checkcap{"bxor", 10, a}
+assert(-a == a); checkcap{"unm", a, a}
+assert(a^4.0 == a); checkcap{"pow", a, 4.0}
+assert(a^'4' == a); checkcap{"pow", a, '4'}
+assert(4^a == 4); checkcap{"pow", 4, a}
+assert('4'^a == '4'); checkcap{"pow", '4', a}
+assert(#a == a); checkcap{"len", a, a}
+assert(~a == a); checkcap{"bnot", a, a}
+assert(a << 3 == a); checkcap{"shl", a, 3}
+assert(1.5 >> a == 1.5); checkcap{"shr", 1.5, a}
+
+-- for comparison operators, all results are true
+assert(5.0 > a); checkcap{"lt", a, 5.0}
+assert(a >= 10); checkcap{"le", 10, a}
+assert(a <= -10.0); checkcap{"le", a, -10.0}
+assert(a < -10); checkcap{"lt", a, -10}
+
+
+-- test for rawlen
+t = setmetatable({1,2,3}, {__len = function () return 10 end})
+assert(#t == 10 and rawlen(t) == 3)
+assert(rawlen"abc" == 3)
+assert(not pcall(rawlen, io.stdin))
+assert(not pcall(rawlen, 34))
+assert(not pcall(rawlen))
+
+-- rawlen for long strings
+assert(rawlen(string.rep('a', 1000)) == 1000)
+
+
+t = {}
+t.__lt = function (a,b,c)
+  collectgarbage()
+  assert(c == nil)
+  if type(a) == 'table' then a = a.x end
+  if type(b) == 'table' then b = b.x end
+ return a<b, "dummy"
+end
+
+t.__le = function (a,b,c)
+  assert(c == nil)
+  if type(a) == 'table' then a = a.x end
+  if type(b) == 'table' then b = b.x end
+ return a<=b, "dummy"
+end
+
+t.__eq = function (a,b,c)
+  assert(c == nil)
+  if type(a) == 'table' then a = a.x end
+  if type(b) == 'table' then b = b.x end
+ return a == b, "dummy"
+end
+
+function Op(x) return setmetatable({x=x}, t) end
+
+local function test (a, b, c)
+  assert(not(Op(1)<Op(1)) and (Op(1)<Op(2)) and not(Op(2)<Op(1)))
+  assert(not(1 < Op(1)) and (Op(1) < 2) and not(2 < Op(1)))
+  assert(not(Op('a')<Op('a')) and (Op('a')<Op('b')) and not(Op('b')<Op('a')))
+  assert(not('a' < Op('a')) and (Op('a') < 'b') and not(Op('b') < Op('a')))
+  assert((Op(1)<=Op(1)) and (Op(1)<=Op(2)) and not(Op(2)<=Op(1)))
+  assert((Op('a')<=Op('a')) and (Op('a')<=Op('b')) and not(Op('b')<=Op('a')))
+  assert(not(Op(1)>Op(1)) and not(Op(1)>Op(2)) and (Op(2)>Op(1)))
+  assert(not(Op('a')>Op('a')) and not(Op('a')>Op('b')) and (Op('b')>Op('a')))
+  assert((Op(1)>=Op(1)) and not(Op(1)>=Op(2)) and (Op(2)>=Op(1)))
+  assert((1 >= Op(1)) and not(1 >= Op(2)) and (Op(2) >= 1))
+  assert((Op('a')>=Op('a')) and not(Op('a')>=Op('b')) and (Op('b')>=Op('a')))
+  assert(('a' >= Op('a')) and not(Op('a') >= 'b') and (Op('b') >= Op('a')))
+  assert(Op(1) == Op(1) and Op(1) ~= Op(2))
+  assert(Op('a') == Op('a') and Op('a') ~= Op('b'))
+  assert(a == a and a ~= b)
+  assert(Op(3) == c)
+end
+
+test(Op(1), Op(2), Op(3))
+
+
+-- test `partial order'
+
+local function rawSet(x)
+  local y = {}
+  for _,k in pairs(x) do y[k] = 1 end
+  return y
+end
+
+local function Set(x)
+  return setmetatable(rawSet(x), t)
+end
+
+t.__lt = function (a,b)
+  for k in pairs(a) do
+    if not b[k] then return false end
+    b[k] = undef
+  end
+  return next(b) ~= nil
+end
+
+t.__le = function (a,b)
+  for k in pairs(a) do
+    if not b[k] then return false end
+  end
+  return true
+end
+
+assert(Set{1,2,3} < Set{1,2,3,4})
+assert(not(Set{1,2,3,4} < Set{1,2,3,4}))
+assert((Set{1,2,3,4} <= Set{1,2,3,4}))
+assert((Set{1,2,3,4} >= Set{1,2,3,4}))
+assert(not (Set{1,3} <= Set{3,5}))
+assert(not(Set{1,3} <= Set{3,5}))
+assert(not(Set{1,3} >= Set{3,5}))
+
+
+t.__eq = function (a,b)
+  for k in pairs(a) do
+    if not b[k] then return false end
+    b[k] = undef
+  end
+  return next(b) == nil
+end
+
+local s = Set{1,3,5}
+assert(s == Set{3,5,1})
+assert(not rawequal(s, Set{3,5,1}))
+assert(rawequal(s, s))
+assert(Set{1,3,5,1} == rawSet{3,5,1})
+assert(rawSet{1,3,5,1} == Set{3,5,1})
+assert(Set{1,3,5} ~= Set{3,5,1,6})
+
+-- '__eq' is not used for table accesses
+t[Set{1,3,5}] = 1
+assert(t[Set{1,3,5}] == undef)
+
+
+if not T then
+  (Message or print)('\n >>> testC not active: skipping tests for \z
+userdata <<<\n')
+else
+  local u1 = T.newuserdata(0, 1)
+  local u2 = T.newuserdata(0, 1)
+  local u3 = T.newuserdata(0, 1)
+  assert(u1 ~= u2 and u1 ~= u3)
+  debug.setuservalue(u1, 1);
+  debug.setuservalue(u2, 2);
+  debug.setuservalue(u3, 1);
+  debug.setmetatable(u1, {__eq = function (a, b)
+    return debug.getuservalue(a) == debug.getuservalue(b)
+  end})
+  debug.setmetatable(u2, {__eq = function (a, b)
+    return true
+  end})
+  assert(u1 == u3 and u3 == u1 and u1 ~= u2)
+  assert(u2 == u1 and u2 == u3 and u3 == u2)
+  assert(u2 ~= {})   -- different types cannot be equal
+  assert(rawequal(u1, u1) and not rawequal(u1, u3))
+
+  local mirror = {}
+  debug.setmetatable(u3, {__index = mirror, __newindex = mirror})
+  for i = 1, 10 do u3[i] = i end
+  for i = 1, 10 do assert(u3[i] == i) end
+end
+
+
+t.__concat = function (a,b,c)
+  assert(c == nil)
+  if type(a) == 'table' then a = a.val end
+  if type(b) == 'table' then b = b.val end
+  if A then return a..b
+  else
+    return setmetatable({val=a..b}, t)
+  end
+end
+
+c = {val="c"}; setmetatable(c, t)
+d = {val="d"}; setmetatable(d, t)
+
+A = true
+assert(c..d == 'cd')
+assert(0 .."a".."b"..c..d.."e".."f"..(5+3).."g" == "0abcdef8g")
+
+A = false
+assert((c..d..c..d).val == 'cdcd')
+x = c..d
+assert(getmetatable(x) == t and x.val == 'cd')
+x = 0 .."a".."b"..c..d.."e".."f".."g"
+assert(x.val == "0abcdefg")
+
+
+-- concat metamethod x numbers (bug in 5.1.1)
+c = {}
+local x
+setmetatable(c, {__concat = function (a,b)
+  assert(type(a) == "number" and b == c or type(b) == "number" and a == c)
+  return c
+end})
+assert(c..5 == c and 5 .. c == c)
+assert(4 .. c .. 5 == c and 4 .. 5 .. 6 .. 7 .. c == c)
+
+
+-- test comparison compatibilities
+local t1, t2, c, d
+t1 = {};  c = {}; setmetatable(c, t1)
+d = {}
+t1.__eq = function () return true end
+t1.__lt = function () return true end
+t1.__le = function () return false end
+setmetatable(d, t1)
+assert(c == d and c < d and not(d <= c))
+t2 = {}
+t2.__eq = t1.__eq
+t2.__lt = t1.__lt
+setmetatable(d, t2)
+assert(c == d and c < d and not(d <= c))
+
+
+
+-- test for several levels of calls
+local i
+local tt = {
+  __call = function (t, ...)
+    i = i+1
+    if t.f then return t.f(...)
+    else return {...}
+    end
+  end
+}
+
+local a = setmetatable({}, tt)
+local b = setmetatable({f=a}, tt)
+local c = setmetatable({f=b}, tt)
+
+i = 0
+x = c(3,4,5)
+assert(i == 3 and x[1] == 3 and x[3] == 5)
+
+
+assert(_G.X == 20)
+
+print'+'
+
+local _g = _G
+_ENV = setmetatable({}, {__index=function (_,k) return _g[k] end})
+
+
+a = {}
+rawset(a, "x", 1, 2, 3)
+assert(a.x == 1 and rawget(a, "x", 3) == 1)
+
+print '+'
+
+-- testing metatables for basic types
+mt = {__index = function (a,b) return a+b end,
+      __len = function (x) return math.floor(x) end}
+debug.setmetatable(10, mt)
+assert(getmetatable(-2) == mt)
+assert((10)[3] == 13)
+assert((10)["3"] == 13)
+assert(#3.45 == 3)
+debug.setmetatable(23, nil)
+assert(getmetatable(-2) == nil)
+
+debug.setmetatable(true, mt)
+assert(getmetatable(false) == mt)
+mt.__index = function (a,b) return a or b end
+assert((true)[false] == true)
+assert((false)[false] == false)
+debug.setmetatable(false, nil)
+assert(getmetatable(true) == nil)
+
+debug.setmetatable(nil, mt)
+assert(getmetatable(nil) == mt)
+mt.__add = function (a,b) return (a or 1) + (b or 2) end
+assert(10 + nil == 12)
+assert(nil + 23 == 24)
+assert(nil + nil == 3)
+debug.setmetatable(nil, nil)
+assert(getmetatable(nil) == nil)
+
+debug.setmetatable(nil, {})
+
+
+-- loops in delegation
+a = {}; setmetatable(a, a); a.__index = a; a.__newindex = a
+assert(not pcall(function (a,b) return a[b] end, a, 10))
+assert(not pcall(function (a,b,c) a[b] = c end, a, 10, true))
+
+-- bug in 5.1
+T, K, V = nil
+grandparent = {}
+grandparent.__newindex = function(t,k,v) T=t; K=k; V=v end
+
+parent = {}
+parent.__newindex = parent
+setmetatable(parent, grandparent)
+
+child = setmetatable({}, parent)
+child.foo = 10      --> CRASH (on some machines)
+assert(T == parent and K == "foo" and V == 10)
+
+print 'OK'
+
+return 12
+
+
diff --git a/test/external/lua-5.4.0-tests/files.lua b/test/external/lua-5.4.0-tests/files.lua
new file mode 100644
index 0000000..677c0dc
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/files.lua
@@ -0,0 +1,925 @@
+-- $Id: testes/files.lua $
+-- See Copyright Notice in file all.lua
+
+local debug = require "debug"
+
+local maxint = math.maxinteger
+
+assert(type(os.getenv"PATH") == "string")
+
+assert(io.input(io.stdin) == io.stdin)
+assert(not pcall(io.input, "non-existent-file"))
+assert(io.output(io.stdout) == io.stdout)
+
+
+local function testerr (msg, f, ...)
+  local stat, err = pcall(f, ...)
+  return (not stat and string.find(err, msg, 1, true))
+end
+
+
+local function checkerr (msg, f, ...)
+  assert(testerr(msg, f, ...))
+end
+
+
+-- cannot close standard files
+assert(not io.close(io.stdin) and
+       not io.stdout:close() and
+       not io.stderr:close())
+
+-- cannot call close method without an argument (new in 5.3.5)
+checkerr("got no value", io.stdin.close)
+
+
+assert(type(io.input()) == "userdata" and io.type(io.output()) == "file")
+assert(type(io.stdin) == "userdata" and io.type(io.stderr) == "file")
+assert(not io.type(8))
+local a = {}; setmetatable(a, {})
+assert(not io.type(a))
+
+assert(getmetatable(io.input()).__name == "FILE*")
+
+local a,b,c = io.open('xuxu_nao_existe')
+assert(not a and type(b) == "string" and type(c) == "number")
+
+a,b,c = io.open('/a/b/c/d', 'w')
+assert(not a and type(b) == "string" and type(c) == "number")
+
+local file = os.tmpname()
+local f, msg = io.open(file, "w")
+if not f then
+  (Message or print)("'os.tmpname' file cannot be open; skipping file tests")
+
+else  --{  most tests here need tmpname
+f:close()
+
+print('testing i/o')
+
+local otherfile = os.tmpname()
+
+checkerr("invalid mode", io.open, file, "rw")
+checkerr("invalid mode", io.open, file, "rb+")
+checkerr("invalid mode", io.open, file, "r+bk")
+checkerr("invalid mode", io.open, file, "")
+checkerr("invalid mode", io.open, file, "+")
+checkerr("invalid mode", io.open, file, "b")
+assert(io.open(file, "r+b")):close()
+assert(io.open(file, "r+")):close()
+assert(io.open(file, "rb")):close()
+
+assert(os.setlocale('C', 'all'))
+
+io.input(io.stdin); io.output(io.stdout);
+
+os.remove(file)
+assert(not loadfile(file))
+checkerr("", dofile, file)
+assert(not io.open(file))
+io.output(file)
+assert(io.output() ~= io.stdout)
+
+if not _port then   -- invalid seek
+  local status, msg, code = io.stdin:seek("set", 1000)
+  assert(not status and type(msg) == "string" and type(code) == "number")
+end
+
+assert(io.output():seek() == 0)
+assert(io.write("alo alo"):seek() == string.len("alo alo"))
+assert(io.output():seek("cur", -3) == string.len("alo alo")-3)
+assert(io.write("joao"))
+assert(io.output():seek("end") == string.len("alo joao"))
+
+assert(io.output():seek("set") == 0)
+
+assert(io.write('"álo"', "{a}\n", "second line\n", "third line \n"))
+assert(io.write('çfourth_line'))
+io.output(io.stdout)
+collectgarbage()  -- file should be closed by GC
+assert(io.input() == io.stdin and rawequal(io.output(), io.stdout))
+print('+')
+
+-- test GC for files
+collectgarbage()
+for i=1,120 do
+  for i=1,5 do
+    io.input(file)
+    assert(io.open(file, 'r'))
+    io.lines(file)
+  end
+  collectgarbage()
+end
+
+io.input():close()
+io.close()
+
+assert(os.rename(file, otherfile))
+assert(not os.rename(file, otherfile))
+
+io.output(io.open(otherfile, "ab"))
+assert(io.write("\n\n\t\t  ", 3450, "\n"));
+io.close()
+
+
+do
+  -- closing file by scope
+  local F = nil
+  do
+    local f <close> = assert(io.open(file, "w"))
+    F = f
+  end
+  assert(tostring(F) == "file (closed)")
+end
+assert(os.remove(file))
+
+
+do
+  -- test writing/reading numbers
+  local f <close> = assert(io.open(file, "w"))
+  f:write(maxint, '\n')
+  f:write(string.format("0X%x\n", maxint))
+  f:write("0xABCp-3", '\n')
+  f:write(0, '\n')
+  f:write(-maxint, '\n')
+  f:write(string.format("0x%X\n", -maxint))
+  f:write("-0xABCp-3", '\n')
+  assert(f:close())
+  local f <close> = assert(io.open(file, "r"))
+  assert(f:read("n") == maxint)
+  assert(f:read("n") == maxint)
+  assert(f:read("n") == 0xABCp-3)
+  assert(f:read("n") == 0)
+  assert(f:read("*n") == -maxint)            -- test old format (with '*')
+  assert(f:read("n") == -maxint)
+  assert(f:read("*n") == -0xABCp-3)            -- test old format (with '*')
+end
+assert(os.remove(file))
+
+
+-- testing multiple arguments to io.read
+do
+  local f <close> = assert(io.open(file, "w"))
+  f:write[[
+a line
+another line
+1234
+3.45
+one
+two
+three
+]]
+  local l1, l2, l3, l4, n1, n2, c, dummy
+  assert(f:close())
+  local f <close> = assert(io.open(file, "r"))
+  l1, l2, n1, n2, dummy = f:read("l", "L", "n", "n")
+  assert(l1 == "a line" and l2 == "another line\n" and
+         n1 == 1234 and n2 == 3.45 and dummy == nil)
+  assert(f:close())
+  local f <close> = assert(io.open(file, "r"))
+  l1, l2, n1, n2, c, l3, l4, dummy = f:read(7, "l", "n", "n", 1, "l", "l")
+  assert(l1 == "a line\n" and l2 == "another line" and c == '\n' and
+         n1 == 1234 and n2 == 3.45 and l3 == "one" and l4 == "two"
+         and dummy == nil)
+  assert(f:close())
+  local f <close> = assert(io.open(file, "r"))
+  -- second item failing
+  l1, n1, n2, dummy = f:read("l", "n", "n", "l")
+  assert(l1 == "a line" and not n1)
+end
+assert(os.remove(file))
+
+
+
+-- test yielding during 'dofile'
+f = assert(io.open(file, "w"))
+f:write[[
+local x, z = coroutine.yield(10)
+local y = coroutine.yield(20)
+return x + y * z
+]]
+assert(f:close())
+f = coroutine.wrap(dofile)
+assert(f(file) == 10)
+assert(f(100, 101) == 20)
+assert(f(200) == 100 + 200 * 101)
+assert(os.remove(file))
+
+
+f = assert(io.open(file, "w"))
+-- test number termination
+f:write[[
+-12.3-	-0xffff+  .3|5.E-3X  +234e+13E 0xDEADBEEFDEADBEEFx
+0x1.13Ap+3e
+]]
+-- very long number
+f:write("1234"); for i = 1, 1000 do f:write("0") end;  f:write("\n")
+-- invalid sequences (must read and discard valid prefixes)
+f:write[[
+.e+	0.e;	--;  0xX;
+]]
+assert(f:close())
+f = assert(io.open(file, "r"))
+assert(f:read("n") == -12.3); assert(f:read(1) == "-")
+assert(f:read("n") == -0xffff); assert(f:read(2) == "+ ")
+assert(f:read("n") == 0.3); assert(f:read(1) == "|")
+assert(f:read("n") == 5e-3); assert(f:read(1) == "X")
+assert(f:read("n") == 234e13); assert(f:read(1) == "E")
+assert(f:read("n") == 0Xdeadbeefdeadbeef); assert(f:read(2) == "x\n")
+assert(f:read("n") == 0x1.13aP3); assert(f:read(1) == "e")
+
+do   -- attempt to read too long number
+  assert(not f:read("n"))  -- fails
+  local s = f:read("L")   -- read rest of line
+  assert(string.find(s, "^00*\n$"))  -- lots of 0's left
+end
+
+assert(not f:read("n")); assert(f:read(2) == "e+")
+assert(not f:read("n")); assert(f:read(1) == ";")
+assert(not f:read("n")); assert(f:read(2) == "-;")
+assert(not f:read("n")); assert(f:read(1) == "X")
+assert(not f:read("n")); assert(f:read(1) == ";")
+assert(not f:read("n")); assert(not f:read(0))   -- end of file
+assert(f:close())
+assert(os.remove(file))
+
+
+-- test line generators
+assert(not pcall(io.lines, "non-existent-file"))
+assert(os.rename(otherfile, file))
+io.output(otherfile)
+local n = 0
+local f = io.lines(file)
+while f() do n = n + 1 end;
+assert(n == 6)   -- number of lines in the file
+checkerr("file is already closed", f)
+checkerr("file is already closed", f)
+-- copy from file to otherfile
+n = 0
+for l in io.lines(file) do io.write(l, "\n"); n = n + 1 end
+io.close()
+assert(n == 6)
+-- copy from otherfile back to file
+local f = assert(io.open(otherfile))
+assert(io.type(f) == "file")
+io.output(file)
+assert(not io.output():read())
+n = 0
+for l in f:lines() do io.write(l, "\n"); n = n + 1 end
+assert(tostring(f):sub(1, 5) == "file ")
+assert(f:close()); io.close()
+assert(n == 6)
+checkerr("closed file", io.close, f)
+assert(tostring(f) == "file (closed)")
+assert(io.type(f) == "closed file")
+io.input(file)
+f = io.open(otherfile):lines()
+n = 0
+for l in io.lines() do assert(l == f()); n = n + 1 end
+f = nil; collectgarbage()
+assert(n == 6)
+assert(os.remove(otherfile))
+
+do  -- bug in 5.3.1
+  io.output(otherfile)
+  io.write(string.rep("a", 300), "\n")
+  io.close()
+  local t ={}; for i = 1, 250 do t[i] = 1 end
+  t = {io.lines(otherfile, table.unpack(t))()}
+  -- everything ok here
+  assert(#t == 250 and t[1] == 'a' and t[#t] == 'a')
+  t[#t + 1] = 1    -- one too many
+  checkerr("too many arguments", io.lines, otherfile, table.unpack(t))
+  collectgarbage()   -- ensure 'otherfile' is closed
+  assert(os.remove(otherfile))
+end
+
+io.input(file)
+do  -- test error returns
+  local a,b,c = io.input():write("xuxu")
+  assert(not a and type(b) == "string" and type(c) == "number")
+end
+checkerr("invalid format", io.read, "x")
+assert(io.read(0) == "")   -- not eof
+assert(io.read(5, 'l') == '"álo"')
+assert(io.read(0) == "")
+assert(io.read() == "second line")
+local x = io.input():seek()
+assert(io.read() == "third line ")
+assert(io.input():seek("set", x))
+assert(io.read('L') == "third line \n")
+assert(io.read(1) == "ç")
+assert(io.read(string.len"fourth_line") == "fourth_line")
+assert(io.input():seek("cur", -string.len"fourth_line"))
+assert(io.read() == "fourth_line")
+assert(io.read() == "")  -- empty line
+assert(io.read('n') == 3450)
+assert(io.read(1) == '\n')
+assert(not io.read(0))  -- end of file
+assert(not io.read(1))  -- end of file
+assert(not io.read(30000))  -- end of file
+assert(({io.read(1)})[2] == undef)
+assert(not io.read())  -- end of file
+assert(({io.read()})[2] == undef)
+assert(not io.read('n'))  -- end of file
+assert(({io.read('n')})[2] == undef)
+assert(io.read('a') == '')  -- end of file (OK for 'a')
+assert(io.read('a') == '')  -- end of file (OK for 'a')
+collectgarbage()
+print('+')
+io.close(io.input())
+checkerr(" input file is closed", io.read)
+
+assert(os.remove(file))
+
+local t = '0123456789'
+for i=1,10 do t = t..t; end
+assert(string.len(t) == 10*2^10)
+
+io.output(file)
+io.write("alo"):write("\n")
+io.close()
+checkerr(" output file is closed", io.write)
+local f = io.open(file, "a+b")
+io.output(f)
+collectgarbage()
+
+assert(io.write(' ' .. t .. ' '))
+assert(io.write(';', 'end of file\n'))
+f:flush(); io.flush()
+f:close()
+print('+')
+
+io.input(file)
+assert(io.read() == "alo")
+assert(io.read(1) == ' ')
+assert(io.read(string.len(t)) == t)
+assert(io.read(1) == ' ')
+assert(io.read(0))
+assert(io.read('a') == ';end of file\n')
+assert(not io.read(0))
+assert(io.close(io.input()))
+
+
+-- test errors in read/write
+do
+  local function ismsg (m)
+    -- error message is not a code number
+    return (type(m) == "string" and not tonumber(m))
+  end
+
+  -- read
+  local f = io.open(file, "w")
+  local r, m, c = f:read()
+  assert(not r and ismsg(m) and type(c) == "number")
+  assert(f:close())
+  -- write
+  f = io.open(file, "r")
+  r, m, c = f:write("whatever")
+  assert(not r and ismsg(m) and type(c) == "number")
+  assert(f:close())
+  -- lines
+  f = io.open(file, "w")
+  r, m = pcall(f:lines())
+  assert(r == false and ismsg(m))
+  assert(f:close())
+end
+
+assert(os.remove(file))
+
+-- test for L format
+io.output(file); io.write"\n\nline\nother":close()
+io.input(file)
+assert(io.read"L" == "\n")
+assert(io.read"L" == "\n")
+assert(io.read"L" == "line\n")
+assert(io.read"L" == "other")
+assert(not io.read"L")
+io.input():close()
+
+local f = assert(io.open(file))
+local s = ""
+for l in f:lines("L") do s = s .. l end
+assert(s == "\n\nline\nother")
+f:close()
+
+io.input(file)
+s = ""
+for l in io.lines(nil, "L") do s = s .. l end
+assert(s == "\n\nline\nother")
+io.input():close()
+
+s = ""
+for l in io.lines(file, "L") do s = s .. l end
+assert(s == "\n\nline\nother")
+
+s = ""
+for l in io.lines(file, "l") do s = s .. l end
+assert(s == "lineother")
+
+io.output(file); io.write"a = 10 + 34\na = 2*a\na = -a\n":close()
+local t = {}
+assert(load(io.lines(file, "L"), nil, nil, t))()
+assert(t.a == -((10 + 34) * 2))
+
+
+do   -- testing closing file in line iteration
+
+  -- get the to-be-closed variable from a loop
+  local function gettoclose (lv)
+    lv = lv + 1
+    local stvar = 0   -- to-be-closed is 4th state variable in the loop
+    for i = 1, 1000 do
+      local n, v = debug.getlocal(lv, i)
+      if n == "(for state)" then
+        stvar = stvar + 1
+        if stvar == 4 then return v end
+      end
+    end
+  end
+
+  local f
+  for l in io.lines(file) do
+    f = gettoclose(1)
+    assert(io.type(f) == "file")
+    break
+  end
+  assert(io.type(f) == "closed file")
+
+  f = nil
+  local function foo (name)
+    for l in io.lines(name) do
+      f = gettoclose(1)
+      assert(io.type(f) == "file")
+      error(f)   -- exit loop with an error
+    end
+  end
+  local st, msg = pcall(foo, file)
+  assert(st == false and io.type(msg) == "closed file")
+
+end
+
+
+-- test for multipe arguments in 'lines'
+io.output(file); io.write"0123456789\n":close()
+for a,b in io.lines(file, 1, 1) do
+  if a == "\n" then assert(not b)
+  else assert(tonumber(a) == tonumber(b) - 1)
+  end
+end
+
+for a,b,c in io.lines(file, 1, 2, "a") do
+  assert(a == "0" and b == "12" and c == "3456789\n")
+end
+
+for a,b,c in io.lines(file, "a", 0, 1) do
+  if a == "" then break end
+  assert(a == "0123456789\n" and not b and not c)
+end
+collectgarbage()   -- to close file in previous iteration
+
+io.output(file); io.write"00\n10\n20\n30\n40\n":close()
+for a, b in io.lines(file, "n", "n") do
+  if a == 40 then assert(not b)
+  else assert(a == b - 10)
+  end
+end
+
+
+-- test load x lines
+io.output(file);
+io.write[[
+local y
+= X
+X =
+X *
+2 +
+X;
+X =
+X
+-                                   y;
+]]:close()
+_G.X = 1
+assert(not load((io.lines(file))))
+collectgarbage()   -- to close file in previous iteration
+load((io.lines(file, "L")))()
+assert(_G.X == 2)
+load((io.lines(file, 1)))()
+assert(_G.X == 4)
+load((io.lines(file, 3)))()
+assert(_G.X == 8)
+
+print('+')
+
+local x1 = "string\n\n\\com \"\"''coisas [[estranhas]] ]]'"
+io.output(file)
+assert(io.write(string.format("x2 = %q\n-- comment without ending EOS", x1)))
+io.close()
+assert(loadfile(file))()
+assert(x1 == x2)
+print('+')
+assert(os.remove(file))
+assert(not os.remove(file))
+assert(not os.remove(otherfile))
+
+-- testing loadfile
+local function testloadfile (s, expres)
+  io.output(file)
+  if s then io.write(s) end
+  io.close()
+  local res = assert(loadfile(file))()
+  assert(os.remove(file))
+  assert(res == expres)
+end
+
+-- loading empty file
+testloadfile(nil, nil)
+
+-- loading file with initial comment without end of line
+testloadfile("# a non-ending comment", nil)
+
+
+-- checking Unicode BOM in files
+testloadfile("\xEF\xBB\xBF# some comment\nreturn 234", 234)
+testloadfile("\xEF\xBB\xBFreturn 239", 239)
+testloadfile("\xEF\xBB\xBF", nil)   -- empty file with a BOM
+
+
+-- checking line numbers in files with initial comments
+testloadfile("# a comment\nreturn require'debug'.getinfo(1).currentline", 2)
+
+
+-- loading binary file
+io.output(io.open(file, "wb"))
+assert(io.write(string.dump(function () return 10, '\0alo\255', 'hi' end)))
+io.close()
+a, b, c = assert(loadfile(file))()
+assert(a == 10 and b == "\0alo\255" and c == "hi")
+assert(os.remove(file))
+
+-- bug in 5.2.1
+do
+  io.output(io.open(file, "wb"))
+  -- save function with no upvalues
+  assert(io.write(string.dump(function () return 1 end)))
+  io.close()
+  f = assert(loadfile(file, "b", {}))
+  assert(type(f) == "function" and f() == 1)
+  assert(os.remove(file))
+end
+
+-- loading binary file with initial comment
+io.output(io.open(file, "wb"))
+assert(io.write("#this is a comment for a binary file\0\n",
+                string.dump(function () return 20, '\0\0\0' end)))
+io.close()
+a, b, c = assert(loadfile(file))()
+assert(a == 20 and b == "\0\0\0" and c == nil)
+assert(os.remove(file))
+
+
+-- 'loadfile' with 'env'
+do
+  local f = io.open(file, 'w')
+  f:write[[
+    if (...) then a = 15; return b, c, d
+    else return _ENV
+    end
+  ]]
+  f:close()
+  local t = {b = 12, c = "xuxu", d = print}
+  local f = assert(loadfile(file, 't', t))
+  local b, c, d = f(1)
+  assert(t.a == 15 and b == 12 and c == t.c and d == print)
+  assert(f() == t)
+  f = assert(loadfile(file, 't', nil))
+  assert(f() == nil)
+  f = assert(loadfile(file))
+  assert(f() == _G)
+  assert(os.remove(file))
+end
+
+
+-- 'loadfile' x modes
+do
+  io.open(file, 'w'):write("return 10"):close()
+  local s, m = loadfile(file, 'b')
+  assert(not s and string.find(m, "a text chunk"))
+  io.open(file, 'w'):write("\27 return 10"):close()
+  local s, m = loadfile(file, 't')
+  assert(not s and string.find(m, "a binary chunk"))
+  assert(os.remove(file))
+end
+
+
+io.output(file)
+assert(io.write("qualquer coisa\n"))
+assert(io.write("mais qualquer coisa"))
+io.close()
+assert(io.output(assert(io.open(otherfile, 'wb')))
+       :write("outra coisa\0\1\3\0\0\0\0\255\0")
+       :close())
+
+local filehandle = assert(io.open(file, 'r+'))
+local otherfilehandle = assert(io.open(otherfile, 'rb'))
+assert(filehandle ~= otherfilehandle)
+assert(type(filehandle) == "userdata")
+assert(filehandle:read('l') == "qualquer coisa")
+io.input(otherfilehandle)
+assert(io.read(string.len"outra coisa") == "outra coisa")
+assert(filehandle:read('l') == "mais qualquer coisa")
+filehandle:close();
+assert(type(filehandle) == "userdata")
+io.input(otherfilehandle)
+assert(io.read(4) == "\0\1\3\0")
+assert(io.read(3) == "\0\0\0")
+assert(io.read(0) == "")        -- 255 is not eof
+assert(io.read(1) == "\255")
+assert(io.read('a') == "\0")
+assert(not io.read(0))
+assert(otherfilehandle == io.input())
+otherfilehandle:close()
+assert(os.remove(file))
+assert(os.remove(otherfile))
+collectgarbage()
+
+io.output(file)
+  :write[[
+ 123.4	-56e-2  not a number
+second line
+third line
+
+and the rest of the file
+]]
+  :close()
+io.input(file)
+local _,a,b,c,d,e,h,__ = io.read(1, 'n', 'n', 'l', 'l', 'l', 'a', 10)
+assert(io.close(io.input()))
+assert(_ == ' ' and not __)
+assert(type(a) == 'number' and a==123.4 and b==-56e-2)
+assert(d=='second line' and e=='third line')
+assert(h==[[
+
+and the rest of the file
+]])
+assert(os.remove(file))
+collectgarbage()
+
+-- testing buffers
+do
+  local f = assert(io.open(file, "w"))
+  local fr = assert(io.open(file, "r"))
+  assert(f:setvbuf("full", 2000))
+  f:write("x")
+  assert(fr:read("all") == "")  -- full buffer; output not written yet
+  f:close()
+  fr:seek("set")
+  assert(fr:read("all") == "x")   -- `close' flushes it
+  f = assert(io.open(file), "w")
+  assert(f:setvbuf("no"))
+  f:write("x")
+  fr:seek("set")
+  assert(fr:read("all") == "x")  -- no buffer; output is ready
+  f:close()
+  f = assert(io.open(file, "a"))
+  assert(f:setvbuf("line"))
+  f:write("x")
+  fr:seek("set", 1)
+  assert(fr:read("all") == "")   -- line buffer; no output without `\n'
+  f:write("a\n"):seek("set", 1)
+  assert(fr:read("all") == "xa\n")  -- now we have a whole line
+  f:close(); fr:close()
+  assert(os.remove(file))
+end
+
+
+if not _soft then
+  print("testing large files (> BUFSIZ)")
+  io.output(file)
+  for i=1,5001 do io.write('0123456789123') end
+  io.write('\n12346'):close()
+  io.input(file)
+  local x = io.read('a')
+  io.input():seek('set', 0)
+  local y = io.read(30001)..io.read(1005)..io.read(0)..
+            io.read(1)..io.read(100003)
+  assert(x == y and string.len(x) == 5001*13 + 6)
+  io.input():seek('set', 0)
+  y = io.read()  -- huge line
+  assert(x == y..'\n'..io.read())
+  assert(not io.read())
+  io.close(io.input())
+  assert(os.remove(file))
+  x = nil; y = nil
+end
+
+if not _port then
+  local progname
+  do  -- get name of running executable
+    local arg = arg or ARG
+    local i = 0
+    while arg[i] do i = i - 1 end
+    progname = '"' .. arg[i + 1] .. '"'
+  end
+  print("testing popen/pclose and execute")
+  local tests = {
+    -- command,   what,  code
+    {"ls > /dev/null", "ok"},
+    {"not-to-be-found-command", "exit"},
+    {"exit 3", "exit", 3},
+    {"exit 129", "exit", 129},
+    {"kill -s HUP $$", "signal", 1},
+    {"kill -s KILL $$", "signal", 9},
+    {"sh -c 'kill -s HUP $$'", "exit"},
+    {progname .. ' -e " "', "ok"},
+    {progname .. ' -e "os.exit(0, true)"', "ok"},
+    {progname .. ' -e "os.exit(20, true)"', "exit", 20},
+  }
+  print("\n(some error messages are expected now)")
+  for _, v in ipairs(tests) do
+    local x, y, z = io.popen(v[1]):close()
+    local x1, y1, z1 = os.execute(v[1])
+    assert(x == x1 and y == y1 and z == z1)
+    if v[2] == "ok" then
+      assert(x and y == 'exit' and z == 0)
+    else
+      assert(not x and y == v[2])   -- correct status and 'what'
+      -- correct code if known (but always different from 0)
+      assert((v[3] == nil and z > 0) or v[3] == z)
+    end
+  end
+end
+
+
+-- testing tmpfile
+f = io.tmpfile()
+assert(io.type(f) == "file")
+f:write("alo")
+f:seek("set")
+assert(f:read"a" == "alo")
+
+end --}
+
+print'+'
+
+print("testing date/time")
+
+assert(os.date("") == "")
+assert(os.date("!") == "")
+assert(os.date("\0\0") == "\0\0")
+assert(os.date("!\0\0") == "\0\0")
+local x = string.rep("a", 10000)
+assert(os.date(x) == x)
+local t = os.time()
+D = os.date("*t", t)
+assert(os.date(string.rep("%d", 1000), t) ==
+       string.rep(os.date("%d", t), 1000))
+assert(os.date(string.rep("%", 200)) == string.rep("%", 100))
+
+local function checkDateTable (t)
+  _G.D = os.date("*t", t)
+  assert(os.time(D) == t)
+  load(os.date([[assert(D.year==%Y and D.month==%m and D.day==%d and
+    D.hour==%H and D.min==%M and D.sec==%S and
+    D.wday==%w+1 and D.yday==%j)]], t))()
+  _G.D = nil
+end
+
+checkDateTable(os.time())
+if not _port then
+  -- assume that time_t can represent these values
+  checkDateTable(0)
+  checkDateTable(1)
+  checkDateTable(1000)
+  checkDateTable(0x7fffffff)
+  checkDateTable(0x80000000)
+end
+
+checkerr("invalid conversion specifier", os.date, "%")
+checkerr("invalid conversion specifier", os.date, "%9")
+checkerr("invalid conversion specifier", os.date, "%")
+checkerr("invalid conversion specifier", os.date, "%O")
+checkerr("invalid conversion specifier", os.date, "%E")
+checkerr("invalid conversion specifier", os.date, "%Ea")
+
+checkerr("not an integer", os.time, {year=1000, month=1, day=1, hour='x'})
+checkerr("not an integer", os.time, {year=1000, month=1, day=1, hour=1.5})
+
+checkerr("missing", os.time, {hour = 12})   -- missing date
+
+
+if string.packsize("i") == 4 then   -- 4-byte ints
+  checkerr("field 'year' is out-of-bound", os.time,
+              {year = -(1 << 31) + 1899, month = 1, day = 1})
+end
+
+if not _port then
+  -- test Posix-specific modifiers
+  assert(type(os.date("%Ex")) == 'string')
+  assert(type(os.date("%Oy")) == 'string')
+
+  -- test large dates (assume at least 4-byte ints and time_t)
+  local t0 = os.time{year = 1970, month = 1, day = 0}
+  local t1 = os.time{year = 1970, month = 1, day = 0, sec = (1 << 31) - 1}
+  assert(t1 - t0 == (1 << 31) - 1)
+  t0 = os.time{year = 1970, month = 1, day = 1}
+  t1 = os.time{year = 1970, month = 1, day = 1, sec = -(1 << 31)}
+  assert(t1 - t0 == -(1 << 31))
+
+  -- test out-of-range dates (at least for Unix)
+  if maxint >= 2^62 then  -- cannot do these tests in Small Lua
+    -- no arith overflows
+    checkerr("out-of-bound", os.time, {year = -maxint, month = 1, day = 1})
+    if string.packsize("i") == 4 then   -- 4-byte ints
+      if testerr("out-of-bound", os.date, "%Y", 2^40) then
+        -- time_t has 4 bytes and therefore cannot represent year 4000
+        print("  4-byte time_t")
+        checkerr("cannot be represented", os.time, {year=4000, month=1, day=1})
+      else
+        -- time_t has 8 bytes; an int year cannot represent a huge time
+        print("  8-byte time_t")
+        checkerr("cannot be represented", os.date, "%Y", 2^60)
+
+        -- this is the maximum year
+        assert(tonumber(os.time
+          {year=(1 << 31) + 1899, month=12, day=31, hour=23, min=59, sec=59}))
+
+        -- this is too much
+        checkerr("represented", os.time,
+          {year=(1 << 31) + 1899, month=12, day=31, hour=23, min=59, sec=60})
+      end
+
+      -- internal 'int' fields cannot hold these values
+      checkerr("field 'day' is out-of-bound", os.time,
+                  {year = 0, month = 1, day = 2^32})
+
+      checkerr("field 'month' is out-of-bound", os.time,
+                  {year = 0, month = -((1 << 31) + 1), day = 1})
+
+      checkerr("field 'year' is out-of-bound", os.time,
+                  {year = (1 << 31) + 1900, month = 1, day = 1})
+
+    else    -- 8-byte ints
+      -- assume time_t has 8 bytes too
+      print("  8-byte time_t")
+      assert(tonumber(os.date("%Y", 2^60)))
+
+      -- but still cannot represent a huge year
+      checkerr("cannot be represented", os.time, {year=2^60, month=1, day=1})
+    end
+  end
+end
+
+do
+  local D = os.date("*t")
+  local t = os.time(D)
+  if D.isdst == nil then
+    print("no daylight saving information")
+  else
+    assert(type(D.isdst) == 'boolean')
+  end
+  D.isdst = nil
+  local t1 = os.time(D)
+  assert(t == t1)   -- if isdst is absent uses correct default
+end
+
+local D = os.date("*t")
+t = os.time(D)
+D.year = D.year-1;
+local t1 = os.time(D)
+-- allow for leap years
+assert(math.abs(os.difftime(t,t1)/(24*3600) - 365) < 2)
+
+-- should not take more than 1 second to execute these two lines
+t = os.time()
+t1 = os.time(os.date("*t"))
+local diff = os.difftime(t1,t)
+assert(0 <= diff and diff <= 1)
+diff = os.difftime(t,t1)
+assert(-1 <= diff and diff <= 0)
+
+local t1 = os.time{year=2000, month=10, day=1, hour=23, min=12}
+local t2 = os.time{year=2000, month=10, day=1, hour=23, min=10, sec=19}
+assert(os.difftime(t1,t2) == 60*2-19)
+
+-- since 5.3.3, 'os.time' normalizes table fields
+t1 = {year = 2005, month = 1, day = 1, hour = 1, min = 0, sec = -3602}
+os.time(t1)
+assert(t1.day == 31 and t1.month == 12 and t1.year == 2004 and
+       t1.hour == 23 and t1.min == 59 and t1.sec == 58 and
+       t1.yday == 366)
+
+io.output(io.stdout)
+local t = os.date('%d %m %Y %H %M %S')
+local d, m, a, h, min, s = string.match(t,
+                             "(%d+) (%d+) (%d+) (%d+) (%d+) (%d+)")
+d = tonumber(d)
+m = tonumber(m)
+a = tonumber(a)
+h = tonumber(h)
+min = tonumber(min)
+s = tonumber(s)
+io.write(string.format('test done on %2.2d/%2.2d/%d', d, m, a))
+io.write(string.format(', at %2.2d:%2.2d:%2.2d\n', h, min, s))
+io.write(string.format('%s\n', _VERSION))
+
+
diff --git a/test/external/lua-5.4.0-tests/gc.lua b/test/external/lua-5.4.0-tests/gc.lua
new file mode 100644
index 0000000..91915c0
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/gc.lua
@@ -0,0 +1,681 @@
+-- $Id: testes/gc.lua $
+-- See Copyright Notice in file all.lua
+
+print('testing incremental garbage collection')
+
+local debug = require"debug"
+
+assert(collectgarbage("isrunning"))
+
+collectgarbage()
+
+local oldmode = collectgarbage("incremental")
+
+-- changing modes should return previous mode
+assert(collectgarbage("generational") == "incremental")
+assert(collectgarbage("generational") == "generational")
+assert(collectgarbage("incremental") == "generational")
+assert(collectgarbage("incremental") == "incremental")
+
+
+local function nop () end
+
+local function gcinfo ()
+  return collectgarbage"count" * 1024
+end
+
+
+-- test weird parameters to 'collectgarbage'
+do
+  -- save original parameters
+  local a = collectgarbage("setpause", 200)
+  local b = collectgarbage("setstepmul", 200)
+  local t = {0, 2, 10, 90, 500, 5000, 30000, 0x7ffffffe}
+  for i = 1, #t do
+    local p = t[i]
+    for j = 1, #t do
+      local m = t[j]
+      collectgarbage("setpause", p)
+      collectgarbage("setstepmul", m)
+      collectgarbage("step", 0)
+      collectgarbage("step", 10000)
+    end
+  end
+  -- restore original parameters
+  collectgarbage("setpause", a)
+  collectgarbage("setstepmul", b)
+  collectgarbage()
+end
+
+
+_G["while"] = 234
+
+
+--
+-- tests for GC activation when creating different kinds of objects
+--
+local function GC1 ()
+  local u
+  local b     -- (above 'u' it in the stack)
+  local finish = false
+  u = setmetatable({}, {__gc = function () finish = true end})
+  b = {34}
+  repeat u = {} until finish
+  assert(b[1] == 34)   -- 'u' was collected, but 'b' was not
+
+  finish = false; local i = 1
+  u = setmetatable({}, {__gc = function () finish = true end})
+  repeat i = i + 1; u = tostring(i) .. tostring(i) until finish
+  assert(b[1] == 34)   -- 'u' was collected, but 'b' was not
+
+  finish = false
+  u = setmetatable({}, {__gc = function () finish = true end})
+  repeat local i; u = function () return i end until finish
+  assert(b[1] == 34)   -- 'u' was collected, but 'b' was not
+end
+
+local function GC2 ()
+  local u
+  local finish = false
+  u = {setmetatable({}, {__gc = function () finish = true end})}
+  local b = {34}
+  repeat u = {{}} until finish
+  assert(b[1] == 34)   -- 'u' was collected, but 'b' was not
+
+  finish = false; local i = 1
+  u = {setmetatable({}, {__gc = function () finish = true end})}
+  repeat i = i + 1; u = {tostring(i) .. tostring(i)} until finish
+  assert(b[1] == 34)   -- 'u' was collected, but 'b' was not
+
+  finish = false
+  u = {setmetatable({}, {__gc = function () finish = true end})}
+  repeat local i; u = {function () return i end} until finish
+  assert(b[1] == 34)   -- 'u' was collected, but 'b' was not
+end
+
+local function GC()  GC1(); GC2() end
+
+
+do
+  print("creating many objects")
+
+  local limit = 5000
+
+  for i = 1, limit do
+    local a = {}; a = nil
+  end
+
+  local a = "a"
+
+  for i = 1, limit do
+    a = i .. "b";
+    a = string.gsub(a, '(%d%d*)', "%1 %1")
+    a = "a"
+  end
+
+
+
+  a = {}
+
+  function a:test ()
+    for i = 1, limit do
+      load(string.format("function temp(a) return 'a%d' end", i), "")()
+      assert(temp() == string.format('a%d', i))
+    end
+  end
+
+  a:test()
+
+end
+
+
+-- collection of functions without locals, globals, etc.
+do local f = function () end end
+
+
+print("functions with errors")
+prog = [[
+do
+  a = 10;
+  function foo(x,y)
+    a = sin(a+0.456-0.23e-12);
+    return function (z) return sin(%x+z) end
+  end
+  local x = function (w) a=a+w; end
+end
+]]
+do
+  local step = 1
+  if _soft then step = 13 end
+  for i=1, string.len(prog), step do
+    for j=i, string.len(prog), step do
+      pcall(load(string.sub(prog, i, j), ""))
+    end
+  end
+end
+
+foo = nil
+print('long strings')
+x = "01234567890123456789012345678901234567890123456789012345678901234567890123456789"
+assert(string.len(x)==80)
+s = ''
+k = math.min(300, (math.maxinteger // 80) // 2)
+for n = 1, k do s = s..x; j=tostring(n)  end
+assert(string.len(s) == k*80)
+s = string.sub(s, 1, 10000)
+s, i = string.gsub(s, '(%d%d%d%d)', '')
+assert(i==10000 // 4)
+s = nil
+x = nil
+
+assert(_G["while"] == 234)
+
+
+--
+-- test the "size" of basic GC steps (whatever they mean...)
+--
+do
+print("steps")
+
+  print("steps (2)")
+
+  local function dosteps (siz)
+    collectgarbage()
+    local a = {}
+    for i=1,100 do a[i] = {{}}; local b = {} end
+    local x = gcinfo()
+    local i = 0
+    repeat   -- do steps until it completes a collection cycle
+      i = i+1
+    until collectgarbage("step", siz)
+    assert(gcinfo() < x)
+    return i    -- number of steps
+  end
+
+  collectgarbage"stop"
+
+  if not _port then
+    assert(dosteps(10) < dosteps(2))
+  end
+
+  -- collector should do a full collection with so many steps
+  assert(dosteps(20000) == 1)
+  assert(collectgarbage("step", 20000) == true)
+  assert(collectgarbage("step", 20000) == true)
+
+  assert(not collectgarbage("isrunning"))
+  collectgarbage"restart"
+  assert(collectgarbage("isrunning"))
+
+end
+
+
+if not _port then
+  -- test the pace of the collector
+  collectgarbage(); collectgarbage()
+  local x = gcinfo()
+  collectgarbage"stop"
+  repeat
+    local a = {}
+  until gcinfo() > 3 * x
+  collectgarbage"restart"
+  assert(collectgarbage("isrunning"))
+  repeat
+    local a = {}
+  until gcinfo() <= x * 2
+end
+
+
+print("clearing tables")
+lim = 15
+a = {}
+-- fill a with `collectable' indices
+for i=1,lim do a[{}] = i end
+b = {}
+for k,v in pairs(a) do b[k]=v end
+-- remove all indices and collect them
+for n in pairs(b) do
+  a[n] = undef
+  assert(type(n) == 'table' and next(n) == nil)
+  collectgarbage()
+end
+b = nil
+collectgarbage()
+for n in pairs(a) do error'cannot be here' end
+for i=1,lim do a[i] = i end
+for i=1,lim do assert(a[i] == i) end
+
+
+print('weak tables')
+a = {}; setmetatable(a, {__mode = 'k'});
+-- fill a with some `collectable' indices
+for i=1,lim do a[{}] = i end
+-- and some non-collectable ones
+for i=1,lim do a[i] = i end
+for i=1,lim do local s=string.rep('@', i); a[s] = s..'#' end
+collectgarbage()
+local i = 0
+for k,v in pairs(a) do assert(k==v or k..'#'==v); i=i+1 end
+assert(i == 2*lim)
+
+a = {}; setmetatable(a, {__mode = 'v'});
+a[1] = string.rep('b', 21)
+collectgarbage()
+assert(a[1])   -- strings are *values*
+a[1] = undef
+-- fill a with some `collectable' values (in both parts of the table)
+for i=1,lim do a[i] = {} end
+for i=1,lim do a[i..'x'] = {} end
+-- and some non-collectable ones
+for i=1,lim do local t={}; a[t]=t end
+for i=1,lim do a[i+lim]=i..'x' end
+collectgarbage()
+local i = 0
+for k,v in pairs(a) do assert(k==v or k-lim..'x' == v); i=i+1 end
+assert(i == 2*lim)
+
+a = {}; setmetatable(a, {__mode = 'kv'});
+local x, y, z = {}, {}, {}
+-- keep only some items
+a[1], a[2], a[3] = x, y, z
+a[string.rep('$', 11)] = string.rep('$', 11)
+-- fill a with some `collectable' values
+for i=4,lim do a[i] = {} end
+for i=1,lim do a[{}] = i end
+for i=1,lim do local t={}; a[t]=t end
+collectgarbage()
+assert(next(a) ~= nil)
+local i = 0
+for k,v in pairs(a) do
+  assert((k == 1 and v == x) or
+         (k == 2 and v == y) or
+         (k == 3 and v == z) or k==v);
+  i = i+1
+end
+assert(i == 4)
+x,y,z=nil
+collectgarbage()
+assert(next(a) == string.rep('$', 11))
+
+
+-- 'bug' in 5.1
+a = {}
+local t = {x = 10}
+local C = setmetatable({key = t}, {__mode = 'v'})
+local C1 = setmetatable({[t] = 1}, {__mode = 'k'})
+a.x = t  -- this should not prevent 't' from being removed from
+         -- weak table 'C' by the time 'a' is finalized
+
+setmetatable(a, {__gc = function (u)
+                          assert(C.key == nil)
+                          assert(type(next(C1)) == 'table')
+                          end})
+
+a, t = nil
+collectgarbage()
+collectgarbage()
+assert(next(C) == nil and next(C1) == nil)
+C, C1 = nil
+
+
+-- ephemerons
+local mt = {__mode = 'k'}
+a = {{10},{20},{30},{40}}; setmetatable(a, mt)
+x = nil
+for i = 1, 100 do local n = {}; a[n] = {k = {x}}; x = n end
+GC()
+local n = x
+local i = 0
+while n do n = a[n].k[1]; i = i + 1 end
+assert(i == 100)
+x = nil
+GC()
+for i = 1, 4 do assert(a[i][1] == i * 10); a[i] = undef end
+assert(next(a) == nil)
+
+local K = {}
+a[K] = {}
+for i=1,10 do a[K][i] = {}; a[a[K][i]] = setmetatable({}, mt) end
+x = nil
+local k = 1
+for j = 1,100 do
+  local n = {}; local nk = k%10 + 1
+  a[a[K][nk]][n] = {x, k = k}; x = n; k = nk
+end
+GC()
+local n = x
+local i = 0
+while n do local t = a[a[K][k]][n]; n = t[1]; k = t.k; i = i + 1 end
+assert(i == 100)
+K = nil
+GC()
+-- assert(next(a) == nil)
+
+
+-- testing errors during GC
+if T then
+  collectgarbage("stop")   -- stop collection
+  local u = {}
+  local s = {}; setmetatable(s, {__mode = 'k'})
+  setmetatable(u, {__gc = function (o)
+    local i = s[o]
+    s[i] = true
+    assert(not s[i - 1])   -- check proper finalization order
+    if i == 8 then error("@expected@") end   -- error during GC
+  end})
+
+  for i = 6, 10 do
+    local n = setmetatable({}, getmetatable(u))
+    s[n] = i
+  end
+
+  warn("@on"); warn("@store")
+  collectgarbage()
+  assert(string.find(_WARN, "error in __gc metamethod"))
+  assert(string.match(_WARN, "@(.-)@") == "expected"); _WARN = nil
+  for i = 8, 10 do assert(s[i]) end
+
+  for i = 1, 5 do
+    local n = setmetatable({}, getmetatable(u))
+    s[n] = i
+  end
+
+  collectgarbage()
+  for i = 1, 10 do assert(s[i]) end
+
+  getmetatable(u).__gc = nil
+  warn("@normal")
+
+end
+print '+'
+
+
+-- testing userdata
+if T==nil then
+  (Message or print)('\n >>> testC not active: skipping userdata GC tests <<<\n')
+
+else
+
+  local function newproxy(u)
+    return debug.setmetatable(T.newuserdata(0), debug.getmetatable(u))
+  end
+
+  collectgarbage("stop")   -- stop collection
+  local u = newproxy(nil)
+  debug.setmetatable(u, {__gc = true})
+  local s = 0
+  local a = {[u] = 0}; setmetatable(a, {__mode = 'vk'})
+  for i=1,10 do a[newproxy(u)] = i end
+  for k in pairs(a) do assert(getmetatable(k) == getmetatable(u)) end
+  local a1 = {}; for k,v in pairs(a) do a1[k] = v end
+  for k,v in pairs(a1) do a[v] = k end
+  for i =1,10 do assert(a[i]) end
+  getmetatable(u).a = a1
+  getmetatable(u).u = u
+  do
+    local u = u
+    getmetatable(u).__gc = function (o)
+      assert(a[o] == 10-s)
+      assert(a[10-s] == undef) -- udata already removed from weak table
+      assert(getmetatable(o) == getmetatable(u))
+    assert(getmetatable(o).a[o] == 10-s)
+      s=s+1
+    end
+  end
+  a1, u = nil
+  assert(next(a) ~= nil)
+  collectgarbage()
+  assert(s==11)
+  collectgarbage()
+  assert(next(a) == nil)  -- finalized keys are removed in two cycles
+end
+
+
+-- __gc x weak tables
+local u = setmetatable({}, {__gc = true})
+-- __gc metamethod should be collected before running
+setmetatable(getmetatable(u), {__mode = "v"})
+getmetatable(u).__gc = function (o) os.exit(1) end  -- cannot happen
+u = nil
+collectgarbage()
+
+local u = setmetatable({}, {__gc = true})
+local m = getmetatable(u)
+m.x = {[{0}] = 1; [0] = {1}}; setmetatable(m.x, {__mode = "kv"});
+m.__gc = function (o)
+  assert(next(getmetatable(o).x) == nil)
+  m = 10
+end
+u, m = nil
+collectgarbage()
+assert(m==10)
+
+do   -- tests for string keys in weak tables
+  collectgarbage(); collectgarbage()
+  local m = collectgarbage("count")         -- current memory
+  local a = setmetatable({}, {__mode = "kv"})
+  a[string.rep("a", 2^22)] = 25   -- long string key -> number value
+  a[string.rep("b", 2^22)] = {}   -- long string key -> colectable value
+  a[{}] = 14                     -- colectable key
+  assert(collectgarbage("count") > m + 2^13)    -- 2^13 == 2 * 2^22 in KB
+  collectgarbage()
+  assert(collectgarbage("count") >= m + 2^12 and
+        collectgarbage("count") < m + 2^13)    -- one key was collected
+  local k, v = next(a)   -- string key with number value preserved
+  assert(k == string.rep("a", 2^22) and v == 25)
+  assert(next(a, k) == nil)  -- everything else cleared
+  assert(a[string.rep("b", 2^22)] == undef)
+  a[k] = undef        -- erase this last entry
+  k = nil
+  collectgarbage()
+  assert(next(a) == nil)
+  -- make sure will not try to compare with dead key
+  assert(a[string.rep("b", 100)] == undef)
+  assert(collectgarbage("count") <= m + 1)   -- eveything collected
+end
+
+
+-- errors during collection
+if T then
+  warn("@store")
+  u = setmetatable({}, {__gc = function () error "@expected error" end})
+  u = nil
+  collectgarbage()
+  assert(string.find(_WARN, "@expected error")); _WARN = nil
+  warn("@normal")
+end
+
+
+if not _soft then
+  print("long list")
+  local a = {}
+  for i = 1,200000 do
+    a = {next = a}
+  end
+  a = nil
+  collectgarbage()
+end
+
+-- create many threads with self-references and open upvalues
+print("self-referenced threads")
+local thread_id = 0
+local threads = {}
+
+local function fn (thread)
+    local x = {}
+    threads[thread_id] = function()
+                             thread = x
+                         end
+    coroutine.yield()
+end
+
+while thread_id < 1000 do
+    local thread = coroutine.create(fn)
+    coroutine.resume(thread, thread)
+    thread_id = thread_id + 1
+end
+
+
+-- Create a closure (function inside 'f') with an upvalue ('param') that
+-- points (through a table) to the closure itself and to the thread
+-- ('co' and the initial value of 'param') where closure is running.
+-- Then, assert that table (and therefore everything else) will be
+-- collected.
+do
+  local collected = false   -- to detect collection
+  collectgarbage(); collectgarbage("stop")
+  do
+    local function f (param)
+      ;(function ()
+        assert(type(f) == 'function' and type(param) == 'thread')
+        param = {param, f}
+        setmetatable(param, {__gc = function () collected = true end})
+        coroutine.yield(100)
+      end)()
+    end
+    local co = coroutine.create(f)
+    assert(coroutine.resume(co, co))
+  end
+  -- Now, thread and closure are not reacheable any more.
+  collectgarbage()
+  assert(collected)
+  collectgarbage("restart")
+end
+
+
+do
+  collectgarbage()
+  collectgarbage"stop"
+  collectgarbage("step", 0)   -- steps should not unblock the collector
+  local x = gcinfo()
+  repeat
+    for i=1,1000 do _ENV.a = {} end   -- no collection during the loop
+  until gcinfo() > 2 * x
+  collectgarbage"restart"
+end
+
+
+if T then   -- tests for weird cases collecting upvalues
+
+  local function foo ()
+    local a = {x = 20}
+    coroutine.yield(function () return a.x end)  -- will run collector
+    assert(a.x == 20)   -- 'a' is 'ok'
+    a = {x = 30}   -- create a new object
+    assert(T.gccolor(a) == "white")   -- of course it is new...
+    coroutine.yield(100)   -- 'a' is still local to this thread
+  end
+
+  local t = setmetatable({}, {__mode = "kv"})
+  collectgarbage(); collectgarbage('stop')
+  -- create coroutine in a weak table, so it will never be marked
+  t.co = coroutine.wrap(foo)
+  local f = t.co()   -- create function to access local 'a'
+  T.gcstate("atomic")   -- ensure all objects are traversed
+  assert(T.gcstate() == "atomic")
+  assert(t.co() == 100)   -- resume coroutine, creating new table for 'a'
+  assert(T.gccolor(t.co) == "white")  -- thread was not traversed
+  T.gcstate("pause")   -- collect thread, but should mark 'a' before that
+  assert(t.co == nil and f() == 30)   -- ensure correct access to 'a'
+
+  collectgarbage("restart")
+
+  -- test barrier in sweep phase (backing userdata to gray)
+  local u = T.newuserdata(0, 1)   -- create a userdata
+  collectgarbage()
+  collectgarbage"stop"
+  local a = {}     -- avoid 'u' as first element in 'allgc'
+  T.gcstate"atomic"
+  T.gcstate"sweepallgc"
+  local x = {}
+  assert(T.gccolor(u) == "black")   -- userdata is "old" (black)
+  assert(T.gccolor(x) == "white")   -- table is "new" (white)
+  debug.setuservalue(u, x)          -- trigger barrier
+  assert(T.gccolor(u) == "gray")   -- userdata changed back to gray
+  collectgarbage"restart"
+
+  print"+"
+end
+
+
+if T then
+  local debug = require "debug"
+  collectgarbage("stop")
+  local x = T.newuserdata(0)
+  local y = T.newuserdata(0)
+  debug.setmetatable(y, {__gc = nop})   -- bless the new udata before...
+  debug.setmetatable(x, {__gc = nop})   -- ...the old one
+  assert(T.gccolor(y) == "white")
+  T.checkmemory()
+  collectgarbage("restart")
+end
+
+
+if T then
+  print("emergency collections")
+  collectgarbage()
+  collectgarbage()
+  T.totalmem(T.totalmem() + 200)
+  for i=1,200 do local a = {} end
+  T.totalmem(0)
+  collectgarbage()
+  local t = T.totalmem("table")
+  local a = {{}, {}, {}}   -- create 4 new tables
+  assert(T.totalmem("table") == t + 4)
+  t = T.totalmem("function")
+  a = function () end   -- create 1 new closure
+  assert(T.totalmem("function") == t + 1)
+  t = T.totalmem("thread")
+  a = coroutine.create(function () end)   -- create 1 new coroutine
+  assert(T.totalmem("thread") == t + 1)
+end
+
+
+-- create an object to be collected when state is closed
+do
+  local setmetatable,assert,type,print,getmetatable =
+        setmetatable,assert,type,print,getmetatable
+  local tt = {}
+  tt.__gc = function (o)
+    assert(getmetatable(o) == tt)
+    -- create new objects during GC
+    local a = 'xuxu'..(10+3)..'joao', {}
+    ___Glob = o  -- ressurrect object!
+    setmetatable({}, tt)  -- creates a new one with same metatable
+    print(">>> closing state " .. "<<<\n")
+  end
+  local u = setmetatable({}, tt)
+  ___Glob = {u}   -- avoid object being collected before program end
+end
+
+-- create several objects to raise errors when collected while closing state
+if T then
+  local error, assert, find, warn = error, assert, string.find, warn
+  local n = 0
+  local lastmsg
+  local mt = {__gc = function (o)
+    n = n + 1
+    assert(n == o[1])
+    if n == 1 then
+      _WARN = nil
+    elseif n == 2 then
+      assert(find(_WARN, "@expected warning"))
+      lastmsg = _WARN    -- get message from previous error (first 'o')
+    else
+      assert(lastmsg == _WARN)  -- subsequent error messages are equal
+    end
+    warn("@store"); _WARN = nil
+    error"@expected warning"
+  end}
+  for i = 10, 1, -1 do
+    -- create object and preserve it until the end
+    table.insert(___Glob, setmetatable({i}, mt))
+  end
+end
+
+-- just to make sure
+assert(collectgarbage'isrunning')
+
+collectgarbage(oldmode)
+
+print('OK')
diff --git a/test/external/lua-5.4.0-tests/gengc.lua b/test/external/lua-5.4.0-tests/gengc.lua
new file mode 100644
index 0000000..b02f471
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/gengc.lua
@@ -0,0 +1,83 @@
+-- $Id: testes/gengc.lua $
+-- See Copyright Notice in file all.lua
+
+print('testing generational garbage collection')
+
+local debug = require"debug"
+
+assert(collectgarbage("isrunning"))
+
+collectgarbage()
+
+local oldmode = collectgarbage("generational")
+
+
+-- ensure that table barrier evolves correctly
+do
+  local U = {}
+  -- full collection makes 'U' old
+  collectgarbage()
+  assert(not T or T.gcage(U) == "old")
+
+  -- U refers to a new table, so it becomes 'touched1'
+  U[1] = {x = {234}}
+  assert(not T or (T.gcage(U) == "touched1" and T.gcage(U[1]) == "new"))
+
+  -- both U and the table survive one more collection
+  collectgarbage("step", 0)
+  assert(not T or (T.gcage(U) == "touched2" and T.gcage(U[1]) == "survival"))
+
+  -- both U and the table survive yet another collection
+  -- now everything is old
+  collectgarbage("step", 0)
+  assert(not T or (T.gcage(U) == "old" and T.gcage(U[1]) == "old1"))
+
+  -- data was not corrupted
+  assert(U[1].x[1] == 234)
+end
+
+
+if T == nil then
+  (Message or print)('\n >>> testC not active: \z
+                             skipping some generational tests <<<\n')
+  print 'OK'
+  return
+end
+
+
+-- ensure that userdata barrier evolves correctly
+do
+  local U = T.newuserdata(0, 1)
+  -- full collection makes 'U' old
+  collectgarbage()
+  assert(T.gcage(U) == "old")
+
+  -- U refers to a new table, so it becomes 'touched1'
+  debug.setuservalue(U, {x = {234}})
+  assert(T.gcage(U) == "touched1" and
+         T.gcage(debug.getuservalue(U)) == "new")
+
+  -- both U and the table survive one more collection
+  collectgarbage("step", 0)
+  assert(T.gcage(U) == "touched2" and
+         T.gcage(debug.getuservalue(U)) == "survival")
+
+  -- both U and the table survive yet another collection
+  -- now everything is old
+  collectgarbage("step", 0)
+  assert(T.gcage(U) == "old" and
+         T.gcage(debug.getuservalue(U)) == "old1")
+
+  -- data was not corrupted
+  assert(debug.getuservalue(U).x[1] == 234)
+end
+
+
+
+-- just to make sure
+assert(collectgarbage'isrunning')
+
+collectgarbage(oldmode)
+
+print('OK')
+
diff --git a/test/external/lua-5.4.0-tests/goto.lua b/test/external/lua-5.4.0-tests/goto.lua
new file mode 100644
index 0000000..4ac6d7d
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/goto.lua
@@ -0,0 +1,271 @@
+-- $Id: testes/goto.lua $
+-- See Copyright Notice in file all.lua
+
+collectgarbage()
+
+local function errmsg (code, m)
+  local st, msg = load(code)
+  assert(not st and string.find(msg, m))
+end
+
+-- cannot see label inside block
+errmsg([[ goto l1; do ::l1:: end ]], "label 'l1'")
+errmsg([[ do ::l1:: end goto l1; ]], "label 'l1'")
+
+-- repeated label
+errmsg([[ ::l1:: ::l1:: ]], "label 'l1'")
+errmsg([[ ::l1:: do ::l1:: end]], "label 'l1'")
+
+
+-- undefined label
+errmsg([[ goto l1; local aa ::l1:: ::l2:: print(3) ]], "local 'aa'")
+
+-- jumping over variable definition
+errmsg([[
+do local bb, cc; goto l1; end
+local aa
+::l1:: print(3)
+]], "local 'aa'")
+
+-- jumping into a block
+errmsg([[ do ::l1:: end goto l1 ]], "label 'l1'")
+errmsg([[ goto l1 do ::l1:: end ]], "label 'l1'")
+
+-- cannot continue a repeat-until with variables
+errmsg([[
+  repeat
+    if x then goto cont end
+    local xuxu = 10
+    ::cont::
+  until xuxu < x
+]], "local 'xuxu'")
+
+-- simple gotos
+local x
+do
+  local y = 12
+  goto l1
+  ::l2:: x = x + 1; goto l3
+  ::l1:: x = y; goto l2
+end
+::l3:: ::l3_1:: assert(x == 13)
+
+
+-- long labels
+do
+  local prog = [[
+  do
+    local a = 1
+    goto l%sa; a = a + 1
+   ::l%sa:: a = a + 10
+    goto l%sb; a = a + 2
+   ::l%sb:: a = a + 20
+    return a
+  end
+  ]]
+  local label = string.rep("0123456789", 40)
+  prog = string.format(prog, label, label, label, label)
+  assert(assert(load(prog))() == 31)
+end
+
+
+-- ok to jump over local dec. to end of block
+do
+  goto l1
+  local a = 23
+  x = a
+  ::l1::;
+end
+
+while true do
+  goto l4
+  goto l1  -- ok to jump over local dec. to end of block
+  goto l1  -- multiple uses of same label
+  local x = 45
+  ::l1:: ;;;
+end
+::l4:: assert(x == 13)
+
+if print then
+  goto l1   -- ok to jump over local dec. to end of block
+  error("should not be here")
+  goto l2   -- ok to jump over local dec. to end of block
+  local x
+  ::l1:: ; ::l2:: ;;
+else end
+
+-- to repeat a label in a different function is OK
+local function foo ()
+  local a = {}
+  goto l3
+  ::l1:: a[#a + 1] = 1; goto l2;
+  ::l2:: a[#a + 1] = 2; goto l5;
+  ::l3::
+  ::l3a:: a[#a + 1] = 3; goto l1;
+  ::l4:: a[#a + 1] = 4; goto l6;
+  ::l5:: a[#a + 1] = 5; goto l4;
+  ::l6:: assert(a[1] == 3 and a[2] == 1 and a[3] == 2 and
+              a[4] == 5 and a[5] == 4)
+  if not a[6] then a[6] = true; goto l3a end   -- do it twice
+end
+
+::l6:: foo()
+
+
+do   -- bug in 5.2 -> 5.3.2
+  local x
+  ::L1::
+  local y             -- cannot join this SETNIL with previous one
+  assert(y == nil)
+  y = true
+  if x == nil then
+    x = 1
+    goto L1
+  else
+    x = x + 1
+  end
+  assert(x == 2 and y == true)
+end
+
+-- bug in 5.3
+do
+  local first = true
+  local a = false
+  if true then
+    goto LBL
+    ::loop::
+    a = true
+    ::LBL::
+    if first then
+      first = false
+      goto loop
+    end
+  end
+  assert(a)
+end
+
+do   -- compiling infinite loops
+  goto escape   -- do not run the infinite loops
+  ::a:: goto a
+  ::b:: goto c
+  ::c:: goto b
+end
+::escape::
+--------------------------------------------------------------------------------
+-- testing closing of upvalues
+
+local debug = require 'debug'
+
+local function foo ()
+  local t = {}
+  do
+  local i = 1
+  local a, b, c, d
+  t[1] = function () return a, b, c, d end
+  ::l1::
+  local b
+  do
+    local c
+    t[#t + 1] = function () return a, b, c, d end    -- t[2], t[4], t[6]
+    if i > 2 then goto l2 end
+    do
+      local d
+      t[#t + 1] = function () return a, b, c, d end   -- t[3], t[5]
+      i = i + 1
+      local a
+      goto l1
+    end
+  end
+  end
+  ::l2:: return t
+end
+
+local a = foo()
+assert(#a == 6)
+
+-- all functions share same 'a'
+for i = 2, 6 do
+  assert(debug.upvalueid(a[1], 1) == debug.upvalueid(a[i], 1))
+end
+
+-- 'b' and 'c' are shared among some of them
+for i = 2, 6 do
+  -- only a[1] uses external 'b'/'b'
+  assert(debug.upvalueid(a[1], 2) ~= debug.upvalueid(a[i], 2))
+  assert(debug.upvalueid(a[1], 3) ~= debug.upvalueid(a[i], 3))
+end
+
+for i = 3, 5, 2 do
+  -- inner functions share 'b'/'c' with previous ones
+  assert(debug.upvalueid(a[i], 2) == debug.upvalueid(a[i - 1], 2))
+  assert(debug.upvalueid(a[i], 3) == debug.upvalueid(a[i - 1], 3))
+  -- but not with next ones
+  assert(debug.upvalueid(a[i], 2) ~= debug.upvalueid(a[i + 1], 2))
+  assert(debug.upvalueid(a[i], 3) ~= debug.upvalueid(a[i + 1], 3))
+end
+
+-- only external 'd' is shared
+for i = 2, 6, 2 do
+  assert(debug.upvalueid(a[1], 4) == debug.upvalueid(a[i], 4))
+end
+
+-- internal 'd's are all different
+for i = 3, 5, 2 do
+  for j = 1, 6 do
+    assert((debug.upvalueid(a[i], 4) == debug.upvalueid(a[j], 4))
+      == (i == j))
+  end
+end
+
+--------------------------------------------------------------------------------
+-- testing if x goto optimizations
+
+local function testG (a)
+  if a == 1 then
+    goto l1
+    error("should never be here!")
+  elseif a == 2 then goto l2
+  elseif a == 3 then goto l3
+  elseif a == 4 then
+    goto l1  -- go to inside the block
+    error("should never be here!")
+    ::l1:: a = a + 1   -- must go to 'if' end
+  else
+    goto l4
+    ::l4a:: a = a * 2; goto l4b
+    error("should never be here!")
+    ::l4:: goto l4a
+    error("should never be here!")
+    ::l4b::
+  end
+  do return a end
+  ::l2:: do return "2" end
+  ::l3:: do return "3" end
+  ::l1:: return "1"
+end
+
+assert(testG(1) == "1")
+assert(testG(2) == "2")
+assert(testG(3) == "3")
+assert(testG(4) == 5)
+assert(testG(5) == 10)
+
+do
+  -- if x back goto out of scope of upvalue
+  local X
+  goto L1
+
+  ::L2:: goto L3
+
+  ::L1:: do
+    local a <close> = setmetatable({}, {__close = function () X = true end})
+    assert(X == nil)
+    if a then goto L2 end   -- jumping back out of scope of 'a'
+  end
+
+  ::L3:: assert(X == true)   -- checks that 'a' was correctly closed
+end
+--------------------------------------------------------------------------------
+
+
+print'OK'
diff --git a/test/external/lua-5.4.0-tests/heavy.lua b/test/external/lua-5.4.0-tests/heavy.lua
new file mode 100644
index 0000000..4731c74
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/heavy.lua
@@ -0,0 +1,173 @@
+-- $Id: heavy.lua,v 1.7 2017/12/29 15:42:15 roberto Exp $
+-- See Copyright Notice in file all.lua
+
+local function teststring ()
+  print("creating a string too long")
+  do
+    local a = "x"
+    local st, msg = pcall(function ()
+      while true do
+        a = a .. a.. a.. a.. a.. a.. a.. a.. a.. a
+         .. a .. a.. a.. a.. a.. a.. a.. a.. a.. a
+         .. a .. a.. a.. a.. a.. a.. a.. a.. a.. a
+         .. a .. a.. a.. a.. a.. a.. a.. a.. a.. a
+         .. a .. a.. a.. a.. a.. a.. a.. a.. a.. a
+         .. a .. a.. a.. a.. a.. a.. a.. a.. a.. a
+         .. a .. a.. a.. a.. a.. a.. a.. a.. a.. a
+         .. a .. a.. a.. a.. a.. a.. a.. a.. a.. a
+         .. a .. a.. a.. a.. a.. a.. a.. a.. a.. a
+         .. a .. a.. a.. a.. a.. a.. a.. a.. a.. a
+         print(string.format("string with %d bytes", #a))
+      end
+    end)
+    assert(not st and
+      (string.find(msg, "string length overflow") or
+       string.find(msg, "not enough memory")))
+    print("string length overflow with " .. #a * 100)
+  end
+  print('+')
+end
+
+local function loadrep (x, what)
+  local p = 1<<20
+  local s = string.rep(x, p)
+  local count = 0
+  local function f()
+    count = count + p
+    if count % (0x80*p) == 0 then
+      io.stderr:write("(", count // 2^20, " M)")
+    end
+    return s
+  end
+  local st, msg = load(f, "=big")
+  print("\nmemory: ", collectgarbage'count' * 1024)
+  msg = string.match(msg, "^[^\n]+")    -- get only first line
+  print(string.format("total: 0x%x %s ('%s')", count, what, msg))
+  return st, msg
+end
+
+
+function controlstruct ()
+  print("control structure too long")
+  local lim = ((1 << 24) - 2) // 3
+  local s = string.rep("a = a + 1\n", lim)
+  s = "while true do " .. s .. "end"
+  assert(load(s))
+  print("ok with " .. lim .. " lines")
+  lim = lim + 3
+  s = string.rep("a = a + 1\n", lim)
+  s = "while true do " .. s .. "end"
+  local st, msg = load(s)
+  assert(not st and string.find(msg, "too long"))
+  print(msg)
+end
+
+
+function manylines ()
+  print("loading chunk with too many lines")
+  local st, msg = loadrep("\n", "lines")
+  assert(not st and string.find(msg, "too many lines"))
+  print('+')
+end
+
+
+function hugeid ()
+  print("loading chunk with huge identifier")
+  local st, msg = loadrep("a", "chars")
+  assert(not st and 
+    (string.find(msg, "lexical element too long") or
+     string.find(msg, "not enough memory")))
+  print('+')
+end
+
+function toomanyinst ()
+  print("loading chunk with too many instructions")
+  local st, msg = loadrep("a = 10; ", "instructions")
+  print('+')
+end
+
+
+local function loadrepfunc (prefix, f)
+  local count = -1
+  local function aux ()
+    count = count + 1
+    if count == 0 then
+      return prefix
+    else
+      if count % (0x100000) == 0 then
+        io.stderr:write("(", count // 2^20, " M)")
+      end
+      return f(count)
+    end
+  end
+  local st, msg = load(aux, "k")
+  print("\nmemory: ", collectgarbage'count' * 1024)
+  msg = string.match(msg, "^[^\n]+")    -- get only first line
+  print("expected error: ", msg)
+end
+
+
+function toomanyconst ()
+  print("loading function with too many constants")
+  loadrepfunc("function foo () return {0,",
+      function (n)
+        -- convert 'n' to a string in the format [["...",]],
+        -- where '...' is a kind of number in base 128
+        -- (in a range that does not include either the double quote
+        -- and the escape.)
+        return string.char(34,
+          ((n // 128^0) & 127) + 128,
+          ((n // 128^1) & 127) + 128,
+          ((n // 128^2) & 127) + 128,
+          ((n // 128^3) & 127) + 128,
+          ((n // 128^4) & 127) + 128,
+          34, 44)
+      end)
+end
+
+
+function toomanystr ()
+  local a = {}
+  local st, msg = pcall(function ()
+    for i = 1, math.huge do
+      if i % (0x100000) == 0 then
+        io.stderr:write("(", i // 2^20, " M)")
+      end
+      a[i] = string.pack("I", i)
+     end
+  end)
+  local size = #a
+  a = collectgarbage'count'
+  print("\nmemory:", a * 1024)
+  print("expected error:", msg)
+  print("size:", size)
+end
+
+
+function toomanyidx ()
+  local a = {}
+  local st, msg = pcall(function ()
+    for i = 1, math.huge do
+      if i % (0x100000) == 0 then
+        io.stderr:write("(", i // 2^20, " M)")
+      end
+      a[i] = i
+     end
+  end)
+  print("\nmemory: ", collectgarbage'count' * 1024)
+  print("expected error: ", msg)
+  print("size:", #a)
+end
+  
+
+
+-- teststring()
+-- controlstruct()
+-- manylines()
+-- hugeid()
+-- toomanyinst()
+-- toomanyconst()
+-- toomanystr()
+toomanyidx()
+
+print "OK"
diff --git a/test/external/lua-5.4.0-tests/libs/lib1.c b/test/external/lua-5.4.0-tests/libs/lib1.c
new file mode 100644
index 0000000..56b6ef4
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/libs/lib1.c
@@ -0,0 +1,44 @@
+#include "lua.h"
+#include "lauxlib.h"
+
+static int id (lua_State *L) {
+  return lua_gettop(L);
+}
+
+
+static const struct luaL_Reg funcs[] = {
+  {"id", id},
+  {NULL, NULL}
+};
+
+
+/* function used by lib11.c */
+LUAMOD_API int lib1_export (lua_State *L) {
+  lua_pushstring(L, "exported");
+  return 1;
+}
+
+
+LUAMOD_API int onefunction (lua_State *L) {
+  luaL_checkversion(L);
+  lua_settop(L, 2);
+  lua_pushvalue(L, 1);
+  return 2;
+}
+
+
+LUAMOD_API int anotherfunc (lua_State *L) {
+  luaL_checkversion(L);
+  lua_pushfstring(L, "%d%%%d\n", (int)lua_tointeger(L, 1),
+                                 (int)lua_tointeger(L, 2));
+  return 1;
+} 
+
+
+LUAMOD_API int luaopen_lib1_sub (lua_State *L) {
+  lua_setglobal(L, "y");  /* 2nd arg: extra value (file name) */
+  lua_setglobal(L, "x");  /* 1st arg: module name */
+  luaL_newlib(L, funcs);
+  return 1;
+}
+
diff --git a/test/external/lua-5.4.0-tests/libs/lib11.c b/test/external/lua-5.4.0-tests/libs/lib11.c
new file mode 100644
index 0000000..377d0c4
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/libs/lib11.c
@@ -0,0 +1,10 @@
+#include "lua.h"
+
+/* function from lib1.c */
+int lib1_export (lua_State *L);
+
+LUAMOD_API int luaopen_lib11 (lua_State *L) {
+  return lib1_export(L);
+}
+
+
diff --git a/test/external/lua-5.4.0-tests/libs/lib2.c b/test/external/lua-5.4.0-tests/libs/lib2.c
new file mode 100644
index 0000000..bc9651e
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/libs/lib2.c
@@ -0,0 +1,23 @@
+#include "lua.h"
+#include "lauxlib.h"
+
+static int id (lua_State *L) {
+  return lua_gettop(L);
+}
+
+
+static const struct luaL_Reg funcs[] = {
+  {"id", id},
+  {NULL, NULL}
+};
+
+
+LUAMOD_API int luaopen_lib2 (lua_State *L) {
+  lua_settop(L, 2);
+  lua_setglobal(L, "y");  /* y gets 2nd parameter */
+  lua_setglobal(L, "x");  /* x gets 1st parameter */
+  luaL_newlib(L, funcs);
+  return 1;
+}
+
+
diff --git a/test/external/lua-5.4.0-tests/libs/lib21.c b/test/external/lua-5.4.0-tests/libs/lib21.c
new file mode 100644
index 0000000..a39b683
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/libs/lib21.c
@@ -0,0 +1,10 @@
+#include "lua.h"
+
+
+int luaopen_lib2 (lua_State *L);
+
+LUAMOD_API int luaopen_lib21 (lua_State *L) {
+  return luaopen_lib2(L);
+}
+
+
diff --git a/test/external/lua-5.4.0-tests/libs/lib22.c b/test/external/lua-5.4.0-tests/libs/lib22.c
new file mode 100644
index 0000000..8e65650
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/libs/lib22.c
@@ -0,0 +1,25 @@
+#include "lua.h"
+#include "lauxlib.h"
+
+static int id (lua_State *L) {
+  lua_pushboolean(L, 1);
+  lua_insert(L, 1);
+  return lua_gettop(L);
+}
+
+
+static const struct luaL_Reg funcs[] = {
+  {"id", id},
+  {NULL, NULL}
+};
+
+
+LUAMOD_API int luaopen_lib2 (lua_State *L) {
+  lua_settop(L, 2);
+  lua_setglobal(L, "y");  /* y gets 2nd parameter */
+  lua_setglobal(L, "x");  /* x gets 1st parameter */
+  luaL_newlib(L, funcs);
+  return 1;
+}
+
+
diff --git a/test/external/lua-5.4.0-tests/libs/makefile b/test/external/lua-5.4.0-tests/libs/makefile
new file mode 100644
index 0000000..a133092
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/libs/makefile
@@ -0,0 +1,27 @@
+# change this variable to point to the directory with Lua headers
+# of the version being tested
+LUA_DIR = ../../
+
+CC = gcc
+
+# compilation should generate Dynamic-Link Libraries
+CFLAGS = -Wall -std=gnu99 -O2 -I$(LUA_DIR) -fPIC -shared
+
+# libraries used by the tests
+all: lib1.so lib11.so lib2.so lib21.so lib2-v2.so
+	touch all
+
+lib1.so: lib1.c $(LUA_DIR)/luaconf.h
+	$(CC) $(CFLAGS) -o lib1.so lib1.c
+
+lib11.so: lib11.c $(LUA_DIR)/luaconf.h
+	$(CC) $(CFLAGS) -o lib11.so lib11.c
+
+lib2.so: lib2.c $(LUA_DIR)/luaconf.h
+	$(CC) $(CFLAGS) -o lib2.so lib2.c
+
+lib21.so: lib21.c $(LUA_DIR)/luaconf.h
+	$(CC) $(CFLAGS) -o lib21.so lib21.c
+
+lib2-v2.so: lib21.c $(LUA_DIR)/luaconf.h
+	$(CC) $(CFLAGS) -o lib2-v2.so lib22.c
diff --git a/test/external/lua-5.4.0-tests/literals.lua b/test/external/lua-5.4.0-tests/literals.lua
new file mode 100644
index 0000000..e101eab
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/literals.lua
@@ -0,0 +1,318 @@
+-- $Id: testes/literals.lua $
+-- See Copyright Notice in file all.lua
+
+print('testing scanner')
+
+local debug = require "debug"
+
+
+local function dostring (x) return assert(load(x), "")() end
+
+dostring("x \v\f = \t\r 'a\0a' \v\f\f")
+assert(x == 'a\0a' and string.len(x) == 3)
+
+-- escape sequences
+assert('\n\"\'\\' == [[
+
+"'\]])
+
+assert(string.find("\a\b\f\n\r\t\v", "^%c%c%c%c%c%c%c$"))
+
+-- assume ASCII just for tests:
+assert("\09912" == 'c12')
+assert("\99ab" == 'cab')
+assert("\099" == '\99')
+assert("\099\n" == 'c\10')
+assert('\0\0\0alo' == '\0' .. '\0\0' .. 'alo')
+
+assert(010 .. 020 .. -030 == "1020-30")
+
+-- hexadecimal escapes
+assert("\x00\x05\x10\x1f\x3C\xfF\xe8" == "\0\5\16\31\60\255\232")
+
+local function lexstring (x, y, n)
+  local f = assert(load('return ' .. x ..
+            ', require"debug".getinfo(1).currentline', ''))
+  local s, l = f()
+  assert(s == y and l == n)
+end
+
+lexstring("'abc\\z  \n   efg'", "abcefg", 2)
+lexstring("'abc\\z  \n\n\n'", "abc", 4)
+lexstring("'\\z  \n\t\f\v\n'",  "", 3)
+lexstring("[[\nalo\nalo\n\n]]", "alo\nalo\n\n", 5)
+lexstring("[[\nalo\ralo\n\n]]", "alo\nalo\n\n", 5)
+lexstring("[[\nalo\ralo\r\n]]", "alo\nalo\n", 4)
+lexstring("[[\ralo\n\ralo\r\n]]", "alo\nalo\n", 4)
+lexstring("[[alo]\n]alo]]", "alo]\n]alo", 2)
+
+assert("abc\z
+        def\z
+        ghi\z
+       " == 'abcdefghi')
+
+
+-- UTF-8 sequences
+assert("\u{0}\u{00000000}\x00\0" == string.char(0, 0, 0, 0))
+
+-- limits for 1-byte sequences
+assert("\u{0}\u{7F}" == "\x00\x7F")
+
+-- limits for 2-byte sequences
+assert("\u{80}\u{7FF}" == "\xC2\x80\xDF\xBF")
+
+-- limits for 3-byte sequences
+assert("\u{800}\u{FFFF}" ==   "\xE0\xA0\x80\xEF\xBF\xBF")
+
+-- limits for 4-byte sequences
+assert("\u{10000}\u{1FFFFF}" == "\xF0\x90\x80\x80\xF7\xBF\xBF\xBF")
+
+-- limits for 5-byte sequences
+assert("\u{200000}\u{3FFFFFF}" == "\xF8\x88\x80\x80\x80\xFB\xBF\xBF\xBF\xBF")
+
+-- limits for 6-byte sequences
+assert("\u{4000000}\u{7FFFFFFF}" ==
+       "\xFC\x84\x80\x80\x80\x80\xFD\xBF\xBF\xBF\xBF\xBF")
+
+
+-- Error in escape sequences
+local function lexerror (s, err)
+  local st, msg = load('return ' .. s, '')
+  if err ~= '<eof>' then err = err .. "'" end
+  assert(not st and string.find(msg, "near .-" .. err))
+end
+
+lexerror([["abc\x"]], [[\x"]])
+lexerror([["abc\x]], [[\x]])
+lexerror([["\x]], [[\x]])
+lexerror([["\x5"]], [[\x5"]])
+lexerror([["\x5]], [[\x5]])
+lexerror([["\xr"]], [[\xr]])
+lexerror([["\xr]], [[\xr]])
+lexerror([["\x.]], [[\x.]])
+lexerror([["\x8%"]], [[\x8%%]])
+lexerror([["\xAG]], [[\xAG]])
+lexerror([["\g"]], [[\g]])
+lexerror([["\g]], [[\g]])
+lexerror([["\."]], [[\%.]])
+
+lexerror([["\999"]], [[\999"]])
+lexerror([["xyz\300"]], [[\300"]])
+lexerror([["   \256"]], [[\256"]])
+
+-- errors in UTF-8 sequences
+lexerror([["abc\u{100000000}"]], [[abc\u{100000000]])   -- too large
+lexerror([["abc\u11r"]], [[abc\u1]])    -- missing '{'
+lexerror([["abc\u"]], [[abc\u"]])    -- missing '{'
+lexerror([["abc\u{11r"]], [[abc\u{11r]])    -- missing '}'
+lexerror([["abc\u{11"]], [[abc\u{11"]])    -- missing '}'
+lexerror([["abc\u{11]], [[abc\u{11]])    -- missing '}'
+lexerror([["abc\u{r"]], [[abc\u{r]])     -- no digits
+
+-- unfinished strings
+lexerror("[=[alo]]", "<eof>")
+lexerror("[=[alo]=", "<eof>")
+lexerror("[=[alo]", "<eof>")
+lexerror("'alo", "<eof>")
+lexerror("'alo \\z  \n\n", "<eof>")
+lexerror("'alo \\z", "<eof>")
+lexerror([['alo \98]], "<eof>")
+
+-- valid characters in variable names
+for i = 0, 255 do
+  local s = string.char(i)
+  assert(not string.find(s, "[a-zA-Z_]") == not load(s .. "=1", ""))
+  assert(not string.find(s, "[a-zA-Z_0-9]") ==
+         not load("a" .. s .. "1 = 1", ""))
+end
+
+
+-- long variable names
+
+var1 = string.rep('a', 15000) .. '1'
+var2 = string.rep('a', 15000) .. '2'
+prog = string.format([[
+  %s = 5
+  %s = %s + 1
+  return function () return %s - %s end
+]], var1, var2, var1, var1, var2)
+local f = dostring(prog)
+assert(_G[var1] == 5 and _G[var2] == 6 and f() == -1)
+var1, var2, f = nil
+print('+')
+
+-- escapes --
+assert("\n\t" == [[
+
+	]])
+assert([[
+
+ $debug]] == "\n $debug")
+assert([[ [ ]] ~= [[ ] ]])
+-- long strings --
+b = "001234567890123456789012345678901234567891234567890123456789012345678901234567890012345678901234567890123456789012345678912345678901234567890123456789012345678900123456789012345678901234567890123456789123456789012345678901234567890123456789001234567890123456789012345678901234567891234567890123456789012345678901234567890012345678901234567890123456789012345678912345678901234567890123456789012345678900123456789012345678901234567890123456789123456789012345678901234567890123456789001234567890123456789012345678901234567891234567890123456789012345678901234567890012345678901234567890123456789012345678912345678901234567890123456789012345678900123456789012345678901234567890123456789123456789012345678901234567890123456789001234567890123456789012345678901234567891234567890123456789012345678901234567890012345678901234567890123456789012345678912345678901234567890123456789012345678900123456789012345678901234567890123456789123456789012345678901234567890123456789"
+assert(string.len(b) == 960)
+prog = [=[
+print('+')
+
+a1 = [["this is a 'string' with several 'quotes'"]]
+a2 = "'quotes'"
+
+assert(string.find(a1, a2) == 34)
+print('+')
+
+a1 = [==[temp = [[an arbitrary value]]; ]==]
+assert(load(a1))()
+assert(temp == 'an arbitrary value')
+-- long strings --
+b = "001234567890123456789012345678901234567891234567890123456789012345678901234567890012345678901234567890123456789012345678912345678901234567890123456789012345678900123456789012345678901234567890123456789123456789012345678901234567890123456789001234567890123456789012345678901234567891234567890123456789012345678901234567890012345678901234567890123456789012345678912345678901234567890123456789012345678900123456789012345678901234567890123456789123456789012345678901234567890123456789001234567890123456789012345678901234567891234567890123456789012345678901234567890012345678901234567890123456789012345678912345678901234567890123456789012345678900123456789012345678901234567890123456789123456789012345678901234567890123456789001234567890123456789012345678901234567891234567890123456789012345678901234567890012345678901234567890123456789012345678912345678901234567890123456789012345678900123456789012345678901234567890123456789123456789012345678901234567890123456789"
+assert(string.len(b) == 960)
+print('+')
+
+a = [[00123456789012345678901234567890123456789123456789012345678901234567890123456789
+00123456789012345678901234567890123456789123456789012345678901234567890123456789
+00123456789012345678901234567890123456789123456789012345678901234567890123456789
+00123456789012345678901234567890123456789123456789012345678901234567890123456789
+00123456789012345678901234567890123456789123456789012345678901234567890123456789
+00123456789012345678901234567890123456789123456789012345678901234567890123456789
+00123456789012345678901234567890123456789123456789012345678901234567890123456789
+00123456789012345678901234567890123456789123456789012345678901234567890123456789
+00123456789012345678901234567890123456789123456789012345678901234567890123456789
+00123456789012345678901234567890123456789123456789012345678901234567890123456789
+00123456789012345678901234567890123456789123456789012345678901234567890123456789
+00123456789012345678901234567890123456789123456789012345678901234567890123456789
+00123456789012345678901234567890123456789123456789012345678901234567890123456789
+00123456789012345678901234567890123456789123456789012345678901234567890123456789
+00123456789012345678901234567890123456789123456789012345678901234567890123456789
+00123456789012345678901234567890123456789123456789012345678901234567890123456789
+00123456789012345678901234567890123456789123456789012345678901234567890123456789
+00123456789012345678901234567890123456789123456789012345678901234567890123456789
+00123456789012345678901234567890123456789123456789012345678901234567890123456789
+00123456789012345678901234567890123456789123456789012345678901234567890123456789
+00123456789012345678901234567890123456789123456789012345678901234567890123456789
+00123456789012345678901234567890123456789123456789012345678901234567890123456789
+00123456789012345678901234567890123456789123456789012345678901234567890123456789
+]]
+assert(string.len(a) == 1863)
+assert(string.sub(a, 1, 40) == string.sub(b, 1, 40))
+x = 1
+]=]
+
+print('+')
+x = nil
+dostring(prog)
+assert(x)
+
+prog = nil
+a = nil
+b = nil
+
+
+-- testing line ends
+prog = [[
+a = 1        -- a comment
+b = 2
+
+
+x = [=[
+hi
+]=]
+y = "\
+hello\r\n\
+"
+return require"debug".getinfo(1).currentline
+]]
+
+for _, n in pairs{"\n", "\r", "\n\r", "\r\n"} do
+  local prog, nn = string.gsub(prog, "\n", n)
+  assert(dostring(prog) == nn)
+  assert(_G.x == "hi\n" and _G.y == "\nhello\r\n\n")
+end
+
+
+-- testing comments and strings with long brackets
+a = [==[]=]==]
+assert(a == "]=")
+
+a = [==[[===[[=[]]=][====[]]===]===]==]
+assert(a == "[===[[=[]]=][====[]]===]===")
+
+a = [====[[===[[=[]]=][====[]]===]===]====]
+assert(a == "[===[[=[]]=][====[]]===]===")
+
+a = [=[]]]]]]]]]=]
+assert(a == "]]]]]]]]")
+
+
+--[===[
+x y z [==[ blu foo
+]==
+]
+]=]==]
+error error]=]===]
+
+-- generate all strings of four of these chars
+local x = {"=", "[", "]", "\n"}
+local len = 4
+local function gen (c, n)
+  if n==0 then coroutine.yield(c)
+  else
+    for _, a in pairs(x) do
+      gen(c..a, n-1)
+    end
+  end
+end
+
+for s in coroutine.wrap(function () gen("", len) end) do
+  assert(s == load("return [====[\n"..s.."]====]", "")())
+end
+
+
+-- testing decimal point locale
+if os.setlocale("pt_BR") or os.setlocale("ptb") then
+  assert(tonumber("3,4") == 3.4 and tonumber"3.4" == 3.4)
+  assert(tonumber("  -.4  ") == -0.4)
+  assert(tonumber("  +0x.41  ") == 0X0.41)
+  assert(not load("a = (3,4)"))
+  assert(assert(load("return 3.4"))() == 3.4)
+  assert(assert(load("return .4,3"))() == .4)
+  assert(assert(load("return 4."))() == 4.)
+  assert(assert(load("return 4.+.5"))() == 4.5)
+
+  assert(" 0x.1 " + " 0x,1" + "-0X.1\t" == 0x0.1)
+
+  assert(not tonumber"inf" and not tonumber"NAN")
+
+  assert(assert(load(string.format("return %q", 4.51)))() == 4.51)
+
+  local a,b = load("return 4.5.")
+  assert(string.find(b, "'4%.5%.'"))
+
+  assert(os.setlocale("C"))
+else
+  (Message or print)(
+   '\n >>> pt_BR locale not available: skipping decimal point tests <<<\n')
+end
+
+
+-- testing %q x line ends
+local s = "a string with \r and \n and \r\n and \n\r"
+local c = string.format("return %q", s)
+assert(assert(load(c))() == s)
+
+-- testing errors
+assert(not load"a = 'non-ending string")
+assert(not load"a = 'non-ending string\n'")
+assert(not load"a = '\\345'")
+assert(not load"a = [=x]")
+
+local function malformednum (n, exp)
+  local s, msg = load("return " .. n)
+  assert(not s and string.find(msg, exp))
+end
+
+malformednum("0xe-", "near <eof>")
+malformednum("0xep-p", "malformed number")
+malformednum("1print()", "malformed number")
+
+print('OK')
diff --git a/test/external/lua-5.4.0-tests/locals.lua b/test/external/lua-5.4.0-tests/locals.lua
new file mode 100644
index 0000000..0e5e0c7
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/locals.lua
@@ -0,0 +1,736 @@
+-- $Id: testes/locals.lua $
+-- See Copyright Notice in file all.lua
+
+print('testing local variables and environments')
+
+local debug = require"debug"
+
+
+-- bug in 5.1:
+
+local function f(x) x = nil; return x end
+assert(f(10) == nil)
+
+local function f() local x; return x end
+assert(f(10) == nil)
+
+local function f(x) x = nil; local y; return x, y end
+assert(f(10) == nil and select(2, f(20)) == nil)
+
+do
+  local i = 10
+  do local i = 100; assert(i==100) end
+  do local i = 1000; assert(i==1000) end
+  assert(i == 10)
+  if i ~= 10 then
+    local i = 20
+  else
+    local i = 30
+    assert(i == 30)
+  end
+end
+
+
+
+f = nil
+
+local f
+x = 1
+
+a = nil
+load('local a = {}')()
+assert(a == nil)
+
+function f (a)
+  local _1, _2, _3, _4, _5
+  local _6, _7, _8, _9, _10
+  local x = 3
+  local b = a
+  local c,d = a,b
+  if (d == b) then
+    local x = 'q'
+    x = b
+    assert(x == 2)
+  else
+    assert(nil)
+  end
+  assert(x == 3)
+  local f = 10
+end
+
+local b=10
+local a; repeat local b; a,b=1,2; assert(a+1==b); until a+b==3
+
+
+assert(x == 1)
+
+f(2)
+assert(type(f) == 'function')
+
+
+local function getenv (f)
+  local a,b = debug.getupvalue(f, 1)
+  assert(a == '_ENV')
+  return b
+end
+
+-- test for global table of loaded chunks
+assert(getenv(load"a=3") == _G)
+local c = {}; local f = load("a = 3", nil, nil, c)
+assert(getenv(f) == c)
+assert(c.a == nil)
+f()
+assert(c.a == 3)
+
+-- old test for limits for special instructions
+do
+  local i = 2
+  local p = 4    -- p == 2^i
+  repeat
+    for j=-3,3 do
+      assert(load(string.format([[local a=%s;
+                                        a=a+%s;
+                                        assert(a ==2^%s)]], j, p-j, i), '')) ()
+      assert(load(string.format([[local a=%s;
+                                        a=a-%s;
+                                        assert(a==-2^%s)]], -j, p-j, i), '')) ()
+      assert(load(string.format([[local a,b=0,%s;
+                                        a=b-%s;
+                                        assert(a==-2^%s)]], -j, p-j, i), '')) ()
+    end
+    p = 2 * p;  i = i + 1
+  until p <= 0
+end
+
+print'+'
+
+
+if rawget(_G, "T") then
+  -- testing clearing of dead elements from tables
+  collectgarbage("stop")   -- stop GC
+  local a = {[{}] = 4, [3] = 0, alo = 1,
+             a1234567890123456789012345678901234567890 = 10}
+
+  local t = T.querytab(a)
+
+  for k,_ in pairs(a) do a[k] = undef end
+  collectgarbage()   -- restore GC and collect dead fields in 'a'
+  for i=0,t-1 do
+    local k = querytab(a, i)
+    assert(k == nil or type(k) == 'number' or k == 'alo')
+  end
+
+  -- testing allocation errors during table insertions
+  local a = {}
+  local function additems ()
+    a.x = true; a.y = true; a.z = true
+    a[1] = true
+    a[2] = true
+  end
+  for i = 1, math.huge do
+    T.alloccount(i)
+    local st, msg = pcall(additems)
+    T.alloccount()
+    local count = 0
+    for k, v in pairs(a) do
+      assert(a[k] == v)
+      count = count + 1
+    end
+    if st then assert(count == 5); break end
+  end
+end
+
+
+-- testing lexical environments
+
+assert(_ENV == _G)
+
+do
+local dummy
+local _ENV = (function (...) return ... end)(_G, dummy)   -- {
+
+do local _ENV = {assert=assert}; assert(true) end
+mt = {_G = _G}
+local foo,x
+A = false    -- "declare" A
+do local _ENV = mt
+  function foo (x)
+    A = x
+    do local _ENV =  _G; A = 1000 end
+    return function (x) return A .. x end
+  end
+end
+assert(getenv(foo) == mt)
+x = foo('hi'); assert(mt.A == 'hi' and A == 1000)
+assert(x('*') == mt.A .. '*')
+
+do local _ENV = {assert=assert, A=10};
+  do local _ENV = {assert=assert, A=20};
+    assert(A==20);x=A
+  end
+  assert(A==10 and x==20)
+end
+assert(x==20)
+
+
+do   -- constants
+  local a<const>, b, c<const> = 10, 20, 30
+  b = a + c + b    -- 'b' is not constant
+  assert(a == 10 and b == 60 and c == 30)
+  local function checkro (name, code)
+    local st, msg = load(code)
+    local gab = string.format("attempt to assign to const variable '%s'", name)
+    assert(not st and string.find(msg, gab))
+  end
+  checkro("y", "local x, y <const>, z = 10, 20, 30; x = 11; y = 12")
+  checkro("x", "local x <const>, y, z <const> = 10, 20, 30; x = 11")
+  checkro("z", "local x <const>, y, z <const> = 10, 20, 30; y = 10; z = 11")
+
+  checkro("z", [[
+    local a, z <const>, b = 10;
+    function foo() a = 20; z = 32; end
+  ]])
+
+  checkro("var1", [[
+    local a, var1 <const> = 10;
+    function foo() a = 20; z = function () var1 = 12; end  end
+  ]])
+end
+
+
+print"testing to-be-closed variables"
+
+local function stack(n) n = ((n == 0) or stack(n - 1)) end
+
+local function func2close (f, x, y)
+  local obj = setmetatable({}, {__close = f})
+  if x then
+    return x, obj, y
+  else
+    return obj
+  end
+end
+
+
+do
+  local a = {}
+  do
+    local b <close> = false   -- not to be closed
+    local x <close> = setmetatable({"x"}, {__close = function (self)
+                                                   a[#a + 1] = self[1] end})
+    local w, y <close>, z = func2close(function (self, err)
+                                assert(err == nil); a[#a + 1] = "y"
+                              end, 10, 20)
+    local c <close> = nil  -- not to be closed
+    a[#a + 1] = "in"
+    assert(w == 10 and z == 20)
+  end
+  a[#a + 1] = "out"
+  assert(a[1] == "in" and a[2] == "y" and a[3] == "x" and a[4] == "out")
+end
+
+do
+  local X = false
+
+  local x, closescope = func2close(function () stack(10); X = true end, 100)
+  assert(x == 100);  x = 101;   -- 'x' is not read-only
+
+  -- closing functions do not corrupt returning values
+  local function foo (x)
+    local _ <close> = closescope
+    return x, X, 23
+  end
+
+  local a, b, c = foo(1.5)
+  assert(a == 1.5 and b == false and c == 23 and X == true)
+
+  X = false
+  foo = function (x)
+    local  _<close> = closescope
+    local y = 15
+    return y
+  end
+
+  assert(foo() == 15 and X == true)
+
+  X = false
+  foo = function ()
+    local x <close> = closescope
+    return x
+  end
+
+  assert(foo() == closescope and X == true)
+
+end
+
+
+-- testing to-be-closed x compile-time constants
+-- (there were some bugs here in Lua 5.4-rc3, due to a confusion
+-- between compile levels and stack levels of variables)
+do
+  local flag = false
+  local x = setmetatable({},
+    {__close = function() assert(flag == false); flag = true end})
+  local y <const> = nil
+  local z <const> = nil
+  do
+      local a <close> = x
+  end
+  assert(flag)   -- 'x' must be closed here
+end
+
+do
+  -- similar problem, but with implicit close in for loops
+  local flag = false
+  local x = setmetatable({},
+    {__close = function () assert(flag == false); flag = true end})
+  -- return an empty iterator, nil, nil, and 'x' to be closed
+  local function a ()
+    return (function () return nil end), nil, nil, x
+  end
+  local v <const> = 1
+  local w <const> = 1
+  local x <const> = 1
+  local y <const> = 1
+  local z <const> = 1
+  for k in a() do
+      a = k
+  end    -- ending the loop must close 'x'
+  assert(flag)   -- 'x' must be closed here
+end
+
+
+
+do
+  -- calls cannot be tail in the scope of to-be-closed variables
+  local X, Y
+  local function foo ()
+    local _ <close> = func2close(function () Y = 10 end)
+    assert(X == true and Y == nil)    -- 'X' not closed yet
+    return 1,2,3
+  end
+
+  local function bar ()
+    local _ <close> = func2close(function () X = false end)
+    X = true
+    do
+      return foo()    -- not a tail call!
+    end
+  end
+
+  local a, b, c, d = bar()
+  assert(a == 1 and b == 2 and c == 3 and X == false and Y == 10 and d == nil)
+end
+
+
+-- auxiliary functions for testing warnings in '__close'
+local function prepwarn ()
+  if not T then   -- no test library?
+    warn("@off")      -- do not show (lots of) warnings
+  else
+    warn("@store")    -- to test the warnings
+  end
+end
+
+
+local function endwarn ()
+  if not T then
+    warn("@on")          -- back to normal
+  else
+    assert(_WARN == nil)
+    warn("@normal")
+  end
+end
+
+
+local function checkwarn (msg)
+  if T then
+    assert(string.find(_WARN, msg))
+    _WARN = nil    -- reset variable to check next warning
+  end
+end
+
+warn("@on")
+
+do print("testing errors in __close")
+
+  prepwarn()
+
+  -- original error is in __close
+  local function foo ()
+
+    local x <close> =
+      func2close(function (self, msg)
+        assert(string.find(msg, "@z"))
+        error("@x")
+      end)
+
+    local x1 <close> =
+      func2close(function (self, msg)
+        checkwarn("@y")
+        assert(string.find(msg, "@z"))
+      end)
+
+    local gc <close> = func2close(function () collectgarbage() end)
+
+    local y <close> =
+      func2close(function (self, msg)
+        assert(string.find(msg, "@z"))  -- first error in 'z'
+        checkwarn("@z")   -- second error in 'z' generated a warning
+        error("@y")
+      end)
+
+    local first = true
+    local z <close> =
+      -- 'z' close is called twice
+      func2close(function (self, msg)
+        if first then
+          assert(msg == nil)
+          first = false
+        else
+         assert(string.find(msg, "@z"))   -- own error
+        end
+        error("@z")
+      end)
+
+    return 200
+  end
+
+  local stat, msg = pcall(foo, false)
+  assert(string.find(msg, "@z"))
+  checkwarn("@x")
+
+
+  -- original error not in __close
+  local function foo ()
+
+    local x <close> =
+      func2close(function (self, msg)
+        assert(msg == 4)
+      end)
+
+    local x1 <close> =
+      func2close(function (self, msg)
+        checkwarn("@y")
+        assert(msg == 4)
+        error("@x1")
+      end)
+
+    local gc <close> = func2close(function () collectgarbage() end)
+
+    local y <close> =
+      func2close(function (self, msg)
+        assert(msg == 4)   -- error in body
+        checkwarn("@z")
+        error("@y")
+      end)
+
+    local first = true
+    local z <close> =
+      func2close(function (self, msg)
+        -- 'z' close is called once
+        assert(first and msg == 4)
+        first = false
+        error("@z")
+      end)
+
+    error(4)    -- original error
+  end
+
+  local stat, msg = pcall(foo, true)
+  assert(msg == 4)
+  checkwarn("@x1")   -- last error
+
+  -- error leaving a block
+  local function foo (...)
+    do
+      local x1 <close> =
+        func2close(function ()
+          checkwarn("@X")
+          error("@Y")
+        end)
+
+      local x123 <close> =
+        func2close(function ()
+          error("@X")
+        end)
+    end
+    os.exit(false)    -- should not run
+  end
+
+  local st, msg = xpcall(foo, debug.traceback)
+  assert(string.match(msg, "^[^ ]* @X"))
+  assert(string.find(msg, "in metamethod 'close'"))
+  checkwarn("@Y")
+
+  -- error in toclose in vararg function
+  local function foo (...)
+    local x123 <close> = func2close(function () error("@x123") end)
+  end
+
+  local st, msg = xpcall(foo, debug.traceback)
+  assert(string.match(msg, "^[^ ]* @x123"))
+  assert(string.find(msg, "in metamethod 'close'"))
+  checkwarn("@x123")   -- from second call to close 'x123'
+
+  endwarn()
+end
+
+
+do   -- errors due to non-closable values
+  local function foo ()
+    local x <close> = {}
+    os.exit(false)    -- should not run
+  end
+  local stat, msg = pcall(foo)
+  assert(not stat and
+    string.find(msg, "variable 'x' got a non%-closable value"))
+
+  local function foo ()
+    local xyz <close> = setmetatable({}, {__close = print})
+    getmetatable(xyz).__close = nil   -- remove metamethod
+  end
+  local stat, msg = pcall(foo)
+  assert(not stat and
+    string.find(msg, "attempt to close non%-closable variable 'xyz'"))
+end
+
+
+if rawget(_G, "T") then
+
+  warn("@off")
+
+  -- memory error inside closing function
+  local function foo ()
+    local y <close> = func2close(function () T.alloccount() end)
+    local x <close> = setmetatable({}, {__close = function ()
+      T.alloccount(0); local x = {}   -- force a memory error
+    end})
+    error(1000)   -- common error inside the function's body
+  end
+
+  stack(5)    -- ensure a minimal number of CI structures
+
+  -- despite memory error, 'y' will be executed and
+  -- memory limit will be lifted
+  local _, msg = pcall(foo)
+  assert(msg == 1000)
+
+  local close = func2close(function (self, msg)
+    T.alloccount()
+    assert(msg == "not enough memory")
+  end)
+
+  -- set a memory limit and return a closing object to remove the limit
+  local function enter (count)
+    stack(10)   -- reserve some stack space
+    T.alloccount(count)
+    return close
+  end
+
+  local function test ()
+    local x <close> = enter(0)   -- set a memory limit
+    -- creation of previous upvalue will raise a memory error
+    assert(false)    -- should not run
+  end
+
+  local _, msg = pcall(test)
+  assert(msg == "not enough memory")
+
+  -- now use metamethod for closing
+  close = setmetatable({}, {__close = function ()
+    T.alloccount()
+  end})
+
+  -- repeat test with extra closing upvalues
+  local function test ()
+    local xxx <close> = func2close(function (self, msg)
+      assert(msg == "not enough memory");
+      error(1000)   -- raise another error
+    end)
+    local xx <close> = func2close(function (self, msg)
+      assert(msg == "not enough memory");
+    end)
+    local x <close> = enter(0)   -- set a memory limit
+    -- creation of previous upvalue will raise a memory error
+    os.exit(false)    -- should not run
+  end
+
+  local _, msg = pcall(test)
+  assert(msg == "not enough memory")   -- reported error is the first one
+
+  do    -- testing 'toclose' in C string buffer
+    collectgarbage()
+    local s = string.rep('a', 10000)    -- large string
+    local m = T.totalmem()
+    collectgarbage("stop")
+    s = string.upper(s)    -- allocate buffer + new string (10K each)
+    -- ensure buffer was deallocated
+    assert(T.totalmem() - m <= 11000)
+    collectgarbage("restart")
+  end
+
+  do   -- now some tests for freeing buffer in case of errors
+    local lim = 10000           -- some size larger than the static buffer
+    local extra = 2000          -- some extra memory (for callinfo, etc.)
+
+    local s = string.rep("a", lim)
+
+    -- concat this table needs two buffer resizes (one for each 's')
+    local a = {s, s}
+
+    collectgarbage()
+
+    m = T.totalmem()
+    collectgarbage("stop")
+
+    -- error in the first buffer allocation
+    T. totalmem(m + extra)
+    assert(not pcall(table.concat, a))
+    -- first buffer was not even allocated
+    assert(T.totalmem() - m <= extra)
+
+    -- error in the second buffer allocation
+    T. totalmem(m + lim + extra)
+    assert(not pcall(table.concat, a))
+    -- first buffer was released by 'toclose'
+    assert(T.totalmem() - m <= extra)
+
+    -- error in creation of final string
+    T.totalmem(m + 2 * lim + extra)
+    assert(not pcall(table.concat, a))
+    -- second buffer was released by 'toclose'
+    assert(T.totalmem() - m <= extra)
+
+    -- userdata, upvalue, buffer, buffer, final string
+    T.totalmem(m + 4*lim + extra)
+    assert(#table.concat(a) == 2*lim)
+
+    T.totalmem(0)     -- remove memory limit
+    collectgarbage("restart")
+
+    print'+'
+  end
+
+  warn("@on")
+end
+
+
+print "to-be-closed variables in coroutines"
+
+do
+  -- an error in a wrapped coroutine closes variables
+  local x = false
+  local y = false
+  local co = coroutine.wrap(function ()
+    local xv <close> = func2close(function () x = true end)
+    do
+      local yv <close> = func2close(function () y = true end)
+      coroutine.yield(100)   -- yield doesn't close variable
+    end
+    coroutine.yield(200)   -- yield doesn't close variable
+    error(23)              -- error does
+  end)
+
+  local b = co()
+  assert(b == 100 and not x and not y)
+  b = co()
+  assert(b == 200 and not x and y)
+  local a, b = pcall(co)
+  assert(not a and b == 23 and x and y)
+end
+
+
+do
+  prepwarn()
+
+  -- error in a wrapped coroutine raising errors when closing a variable
+  local x = 0
+  local co = coroutine.wrap(function ()
+    local xx <close> = func2close(function () x = x + 1; error("@YYY") end)
+    local xv <close> = func2close(function () x = x + 1; error("@XXX") end)
+      coroutine.yield(100)
+      error(200)
+  end)
+  assert(co() == 100); assert(x == 0)
+  local st, msg = pcall(co); assert(x == 2)
+  assert(not st and msg == 200)   -- should get first error raised
+  checkwarn("@YYY")
+
+  local x = 0
+  local y = 0
+  co = coroutine.wrap(function ()
+    local xx <close> = func2close(function () y = y + 1; error("YYY") end)
+    local xv <close> = func2close(function () x = x + 1; error("XXX") end)
+      coroutine.yield(100)
+      return 200
+  end)
+  assert(co() == 100); assert(x == 0)
+  local st, msg = pcall(co)
+  assert(x == 2 and y == 1)   -- first close is called twice
+  -- should get first error raised
+  assert(not st and string.find(msg, "%w+%.%w+:%d+: XXX"))
+  checkwarn("YYY")
+
+  endwarn()
+end
+
+
+-- a suspended coroutine should not close its variables when collected
+local co
+co = coroutine.wrap(function()
+  -- should not run
+  local x <close> = func2close(function () os.exit(false) end)
+  co = nil
+  coroutine.yield()
+end)
+co()                 -- start coroutine
+assert(co == nil)    -- eventually it will be collected
+collectgarbage()
+
+
+-- to-be-closed variables in generic for loops
+do
+  local numopen = 0
+  local function open (x)
+    numopen = numopen + 1
+    return
+      function ()   -- iteraction function
+        x = x - 1
+        if x > 0 then return x end
+      end,
+      nil,   -- state
+      nil,   -- control variable
+      func2close(function () numopen = numopen - 1 end)   -- closing function
+  end
+
+  local s = 0
+  for i in open(10) do
+     s = s + i
+  end
+  assert(s == 45 and numopen == 0)
+
+  local s = 0
+  for i in open(10) do
+     if i < 5 then break end
+     s = s + i
+  end
+  assert(s == 35 and numopen == 0)
+
+  local s = 0
+  for i in open(10) do
+    for j in open(10) do
+       if i + j < 5 then goto endloop end
+       s = s + i
+    end
+  end
+  ::endloop::
+  assert(s == 375 and numopen == 0)
+end
+
+print('OK')
+
+return 5,f
+
+end   -- }
+
diff --git a/test/external/lua-5.4.0-tests/ltests/ltests.c b/test/external/lua-5.4.0-tests/ltests/ltests.c
new file mode 100644
index 0000000..63ad449
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/ltests/ltests.c
@@ -0,0 +1,1877 @@
+/*
+** $Id: ltests.c $
+** Internal Module for Debugging of the Lua Implementation
+** See Copyright Notice in lua.h
+*/
+
+#define ltests_c
+#define LUA_CORE
+
+#include "lprefix.h"
+
+
+#include <limits.h>
+#include <setjmp.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "lua.h"
+
+#include "lapi.h"
+#include "lauxlib.h"
+#include "lcode.h"
+#include "lctype.h"
+#include "ldebug.h"
+#include "ldo.h"
+#include "lfunc.h"
+#include "lmem.h"
+#include "lopcodes.h"
+#include "lopnames.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "lualib.h"
+
+
+
+/*
+** The whole module only makes sense with LUA_DEBUG on
+*/
+#if defined(LUA_DEBUG)
+
+
+void *l_Trick = 0;
+
+
+#define obj_at(L,k)	s2v(L->ci->func + (k))
+
+
+static int runC (lua_State *L, lua_State *L1, const char *pc);
+
+
+static void setnameval (lua_State *L, const char *name, int val) {
+  lua_pushinteger(L, val);
+  lua_setfield(L, -2, name);
+}
+
+
+static void pushobject (lua_State *L, const TValue *o) {
+  setobj2s(L, L->top, o);
+  api_incr_top(L);
+}
+
+
+static void badexit (const char *fmt, const char *s1, const char *s2) {
+  fprintf(stderr, fmt, s1);
+  if (s2)
+    fprintf(stderr, "extra info: %s\n", s2);
+  /* avoid assertion failures when exiting */
+  l_memcontrol.numblocks = l_memcontrol.total = 0;
+  exit(EXIT_FAILURE);
+}
+
+
+static int tpanic (lua_State *L) {
+  const char *msg = lua_tostring(L, -1);
+  if (msg == NULL) msg = "error object is not a string";
+  return (badexit("PANIC: unprotected error in call to Lua API (%s)\n",
+                   msg, NULL),
+          0);  /* do not return to Lua */
+}
+
+
+/*
+** Warning function for tests. First, it concatenates all parts of
+** a warning in buffer 'buff'. Then, it has three modes:
+** - 0.normal: messages starting with '#' are shown on standard output;
+** - other messages abort the tests (they represent real warning
+** conditions; the standard tests should not generate these conditions
+** unexpectedly);
+** - 1.allow: all messages are shown;
+** - 2.store: all warnings go to the global '_WARN';
+*/
+static void warnf (void *ud, const char *msg, int tocont) {
+  lua_State *L = cast(lua_State *, ud);
+  static char buff[200] = "";  /* should be enough for tests... */
+  static int onoff = 0;
+  static int mode = 0;  /* start in normal mode */
+  static int lasttocont = 0;
+  if (!lasttocont && !tocont && *msg == '@') {  /* control message? */
+    if (buff[0] != '\0')
+      badexit("Control warning during warning: %s\naborting...\n", msg, buff);
+    if (strcmp(msg, "@off") == 0)
+      onoff = 0;
+    else if (strcmp(msg, "@on") == 0)
+      onoff = 1;
+    else if (strcmp(msg, "@normal") == 0)
+      mode = 0;
+    else if (strcmp(msg, "@allow") == 0)
+      mode = 1;
+    else if (strcmp(msg, "@store") == 0)
+      mode = 2;
+    else
+      badexit("Invalid control warning in test mode: %s\naborting...\n",
+              msg, NULL);
+    return;
+  }
+  lasttocont = tocont;
+  if (strlen(msg) >= sizeof(buff) - strlen(buff))
+    badexit("warnf-buffer overflow (%s)\n", msg, buff);
+  strcat(buff, msg);  /* add new message to current warning */
+  if (!tocont) {  /* message finished? */
+    lua_unlock(L);
+    if (lua_getglobal(L, "_WARN") == LUA_TNIL)
+      lua_pop(L, 1);  /* ok, no previous unexpected warning */
+    else {
+      badexit("Unhandled warning in store mode: %s\naborting...\n",
+              lua_tostring(L, -1), buff);
+    }
+    lua_lock(L);
+    switch (mode) {
+      case 0: {  /* normal */
+        if (buff[0] != '#' && onoff)  /* unexpected warning? */
+          badexit("Unexpected warning in test mode: %s\naborting...\n",
+                  buff, NULL);
+      }  /* FALLTHROUGH */
+      case 1: {  /* allow */
+        if (onoff)
+          fprintf(stderr, "Lua warning: %s\n", buff);  /* print warning */
+        break;
+      }
+      case 2: {  /* store */
+        lua_unlock(L);
+        lua_pushstring(L, buff);
+        lua_setglobal(L, "_WARN");  /* assign message to global '_WARN' */
+        lua_lock(L);
+        buff[0] = '\0';  /* prepare buffer for next warning */
+        break;
+      }
+    }
+    buff[0] = '\0';  /* prepare buffer for next warning */
+  }
+}
+
+
+/*
+** {======================================================================
+** Controlled version for realloc.
+** =======================================================================
+*/
+
+#define MARK		0x55  /* 01010101 (a nice pattern) */
+
+typedef union Header {
+  LUAI_MAXALIGN;
+  struct {
+    size_t size;
+    int type;
+  } d;
+} Header;
+
+
+#if !defined(EXTERNMEMCHECK)
+
+/* full memory check */
+#define MARKSIZE	16  /* size of marks after each block */
+#define fillmem(mem,size)	memset(mem, -MARK, size)
+
+#else
+
+/* external memory check: don't do it twice */
+#define MARKSIZE	0
+#define fillmem(mem,size)	/* empty */
+
+#endif
+
+
+Memcontrol l_memcontrol =
+  {0UL, 0UL, 0UL, 0UL, (~0UL), {0UL, 0UL, 0UL, 0UL, 0UL, 0UL, 0UL, 0UL, 0UL}};
+
+
+static void freeblock (Memcontrol *mc, Header *block) {
+  if (block) {
+    size_t size = block->d.size;
+    int i;
+    for (i = 0; i < MARKSIZE; i++)  /* check marks after block */
+      lua_assert(*(cast_charp(block + 1) + size + i) == MARK);
+    mc->objcount[block->d.type]--;
+    fillmem(block, sizeof(Header) + size + MARKSIZE);  /* erase block */
+    free(block);  /* actually free block */
+    mc->numblocks--;  /* update counts */
+    mc->total -= size;
+  }
+}
+
+
+void *debug_realloc (void *ud, void *b, size_t oldsize, size_t size) {
+  Memcontrol *mc = cast(Memcontrol *, ud);
+  Header *block = cast(Header *, b);
+  int type;
+  if (mc->memlimit == 0) {  /* first time? */
+    char *limit = getenv("MEMLIMIT");  /* initialize memory limit */
+    mc->memlimit = limit ? strtoul(limit, NULL, 10) : ULONG_MAX;
+  }
+  if (block == NULL) {
+    type = (oldsize < LUA_NUMTAGS) ? oldsize : 0;
+    oldsize = 0;
+  }
+  else {
+    block--;  /* go to real header */
+    type = block->d.type;
+    lua_assert(oldsize == block->d.size);
+  }
+  if (size == 0) {
+    freeblock(mc, block);
+    return NULL;
+  }
+  if (mc->countlimit != ~0UL && size != oldsize) {  /* count limit in use? */
+    if (mc->countlimit == 0)
+      return NULL;  /* fake a memory allocation error */
+    mc->countlimit--;
+  }
+  if (size > oldsize && mc->total+size-oldsize > mc->memlimit)
+    return NULL;  /* fake a memory allocation error */
+  else {
+    Header *newblock;
+    int i;
+    size_t commonsize = (oldsize < size) ? oldsize : size;
+    size_t realsize = sizeof(Header) + size + MARKSIZE;
+    if (realsize < size) return NULL;  /* arithmetic overflow! */
+    newblock = cast(Header *, malloc(realsize));  /* alloc a new block */
+    if (newblock == NULL)
+      return NULL;  /* really out of memory? */
+    if (block) {
+      memcpy(newblock + 1, block + 1, commonsize);  /* copy old contents */
+      freeblock(mc, block);  /* erase (and check) old copy */
+    }
+    /* initialize new part of the block with something weird */
+    fillmem(cast_charp(newblock + 1) + commonsize, size - commonsize);
+    /* initialize marks after block */
+    for (i = 0; i < MARKSIZE; i++)
+      *(cast_charp(newblock + 1) + size + i) = MARK;
+    newblock->d.size = size;
+    newblock->d.type = type;
+    mc->total += size;
+    if (mc->total > mc->maxmem)
+      mc->maxmem = mc->total;
+    mc->numblocks++;
+    mc->objcount[type]++;
+    return newblock + 1;
+  }
+}
+
+
+/* }====================================================================== */
+
+
+
+/*
+** {======================================================
+** Functions to check memory consistency
+** =======================================================
+*/
+
+
+/*
+** Check GC invariants. For incremental mode, a black object cannot
+** point to a white one. For generational mode, really old objects
+** cannot point to young objects. Both old1 and touched2 objects
+** cannot point to new objects (but can point to survivals).
+** (Threads and open upvalues, despite being marked "really old",
+** continue to be visited in all collections, and therefore can point to
+** new objects. They, and only they, are old but gray.)
+*/
+static int testobjref1 (global_State *g, GCObject *f, GCObject *t) {
+  if (isdead(g,t)) return 0;
+  if (issweepphase(g))
+    return 1;  /* no invariants */
+  else if (g->gckind == KGC_INC)
+    return !(isblack(f) && iswhite(t));  /* basic incremental invariant */
+  else {  /* generational mode */
+    if ((getage(f) == G_OLD && isblack(f)) && !isold(t))
+      return 0;
+    if (((getage(f) == G_OLD1 || getage(f) == G_TOUCHED2) && isblack(f)) &&
+          getage(t) == G_NEW)
+      return 0;
+    return 1;
+  }
+}
+
+
+static void printobj (global_State *g, GCObject *o) {
+  printf("||%s(%p)-%c%c(%02X)||",
+           ttypename(novariant(o->tt)), (void *)o,
+           isdead(g,o) ? 'd' : isblack(o) ? 'b' : iswhite(o) ? 'w' : 'g',
+           "ns01oTt"[getage(o)], o->marked);
+  if (o->tt == LUA_VSHRSTR || o->tt == LUA_VLNGSTR)
+    printf(" '%s'", getstr(gco2ts(o)));
+}
+
+
+static int testobjref (global_State *g, GCObject *f, GCObject *t) {
+  int r1 = testobjref1(g, f, t);
+  if (!r1) {
+    printf("%d(%02X) - ", g->gcstate, g->currentwhite);
+    printobj(g, f);
+    printf("  ->  ");
+    printobj(g, t);
+    printf("\n");
+  }
+  return r1;
+}
+
+#define checkobjref(g,f,t)  \
+	{ if (t) lua_longassert(testobjref(g,f,obj2gco(t))); }
+
+
+static void checkvalref (global_State *g, GCObject *f, const TValue *t) {
+  lua_assert(!iscollectable(t) ||
+    (righttt(t) && testobjref(g, f, gcvalue(t))));
+}
+
+
+static void checktable (global_State *g, Table *h) {
+  unsigned int i;
+  unsigned int asize = luaH_realasize(h);
+  Node *n, *limit = gnode(h, sizenode(h));
+  GCObject *hgc = obj2gco(h);
+  checkobjref(g, hgc, h->metatable);
+  for (i = 0; i < asize; i++)
+    checkvalref(g, hgc, &h->array[i]);
+  for (n = gnode(h, 0); n < limit; n++) {
+    if (!isempty(gval(n))) {
+      TValue k;
+      getnodekey(g->mainthread, &k, n);
+      lua_assert(!keyisnil(n));
+      checkvalref(g, hgc, &k);
+      checkvalref(g, hgc, gval(n));
+    }
+  }
+}
+
+
+static void checkudata (global_State *g, Udata *u) {
+  int i;
+  GCObject *hgc = obj2gco(u);
+  checkobjref(g, hgc, u->metatable);
+  for (i = 0; i < u->nuvalue; i++)
+    checkvalref(g, hgc, &u->uv[i].uv);
+}
+
+
+/*
+** All marks are conditional because a GC may happen while the
+** prototype is still being created
+*/
+static void checkproto (global_State *g, Proto *f) {
+  int i;
+  GCObject *fgc = obj2gco(f);
+  checkobjref(g, fgc, f->source);
+  for (i=0; i<f->sizek; i++) {
+    if (ttisstring(f->k + i))
+      checkobjref(g, fgc, tsvalue(f->k + i));
+  }
+  for (i=0; i<f->sizeupvalues; i++)
+    checkobjref(g, fgc, f->upvalues[i].name);
+  for (i=0; i<f->sizep; i++)
+    checkobjref(g, fgc, f->p[i]);
+  for (i=0; i<f->sizelocvars; i++)
+    checkobjref(g, fgc, f->locvars[i].varname);
+}
+
+
+static void checkCclosure (global_State *g, CClosure *cl) {
+  GCObject *clgc = obj2gco(cl);
+  int i;
+  for (i = 0; i < cl->nupvalues; i++)
+    checkvalref(g, clgc, &cl->upvalue[i]);
+}
+
+
+static void checkLclosure (global_State *g, LClosure *cl) {
+  GCObject *clgc = obj2gco(cl);
+  int i;
+  checkobjref(g, clgc, cl->p);
+  for (i=0; i<cl->nupvalues; i++) {
+    UpVal *uv = cl->upvals[i];
+    if (uv) {
+      checkobjref(g, clgc, uv);
+      if (!upisopen(uv))
+        checkvalref(g, obj2gco(uv), uv->v);
+    }
+  }
+}
+
+
+static int lua_checkpc (CallInfo *ci) {
+  if (!isLua(ci)) return 1;
+  else {
+    StkId f = ci->func;
+    Proto *p = clLvalue(s2v(f))->p;
+    return p->code <= ci->u.l.savedpc &&
+           ci->u.l.savedpc <= p->code + p->sizecode;
+  }
+}
+
+
+static void checkstack (global_State *g, lua_State *L1) {
+  StkId o;
+  CallInfo *ci;
+  UpVal *uv;
+  lua_assert(!isdead(g, L1));
+  if (L1->stack == NULL) {  /* incomplete thread? */
+    lua_assert(L1->stacksize == 0 && L1->openupval == NULL &&
+               L1->ci == NULL);
+    return;
+  }
+  for (uv = L1->openupval; uv != NULL; uv = uv->u.open.next)
+    lua_assert(upisopen(uv));  /* must be open */
+  for (ci = L1->ci; ci != NULL; ci = ci->previous) {
+    lua_assert(ci->top <= L1->stack_last);
+    lua_assert(lua_checkpc(ci));
+  }
+  for (o = L1->stack; o < L1->stack_last + EXTRA_STACK; o++)
+    checkliveness(L1, s2v(o));  /* entire stack must have valid values */
+}
+
+
+static void checkrefs (global_State *g, GCObject *o) {
+  switch (o->tt) {
+    case LUA_VUSERDATA: {
+      checkudata(g, gco2u(o));
+      break;
+    }
+    case LUA_VUPVAL: {
+      checkvalref(g, o, gco2upv(o)->v);
+      break;
+    }
+    case LUA_VTABLE: {
+      checktable(g, gco2t(o));
+      break;
+    }
+    case LUA_VTHREAD: {
+      checkstack(g, gco2th(o));
+      break;
+    }
+    case LUA_VLCL: {
+      checkLclosure(g, gco2lcl(o));
+      break;
+    }
+    case LUA_VCCL: {
+      checkCclosure(g, gco2ccl(o));
+      break;
+    }
+    case LUA_VPROTO: {
+      checkproto(g, gco2p(o));
+      break;
+    }
+    case LUA_VSHRSTR:
+    case LUA_VLNGSTR: {
+      lua_assert(!isgray(o));  /* strings are never gray */
+      break;
+    }
+    default: lua_assert(0);
+  }
+}
+
+
+/*
+** Check consistency of an object:
+** - Dead objects can only happen in the 'allgc' list during a sweep
+** phase (controlled by the caller through 'maybedead').
+** - During pause, all objects must be white.
+** - In generational mode:
+**   * objects must be old enough for their lists ('listage').
+**   * old objects cannot be white.
+**   * old objects must be black, except for 'touched1', 'old0',
+** threads, and open upvalues.
+*/
+static void checkobject (global_State *g, GCObject *o, int maybedead,
+                         int listage) {
+  if (isdead(g, o))
+    lua_assert(maybedead);
+  else {
+    lua_assert(g->gcstate != GCSpause || iswhite(o));
+    if (g->gckind == KGC_GEN) {  /* generational mode? */
+      lua_assert(getage(o) >= listage);
+      lua_assert(!iswhite(o) || !isold(o));
+      if (isold(o)) {
+        lua_assert(isblack(o) ||
+        getage(o) == G_TOUCHED1 ||
+        getage(o) == G_OLD0 ||
+        o->tt == LUA_VTHREAD ||
+        (o->tt == LUA_VUPVAL && upisopen(gco2upv(o))));
+      }
+    }
+    checkrefs(g, o);
+  }
+}
+
+
+static void checkgraylist (global_State *g, GCObject *o) {
+  ((void)g);  /* better to keep it available if we need to print an object */
+  while (o) {
+    lua_assert(isgray(o) || getage(o) == G_TOUCHED2);
+    switch (o->tt) {
+      case LUA_VTABLE: o = gco2t(o)->gclist; break;
+      case LUA_VLCL: o = gco2lcl(o)->gclist; break;
+      case LUA_VCCL: o = gco2ccl(o)->gclist; break;
+      case LUA_VTHREAD: o = gco2th(o)->gclist; break;
+      case LUA_VPROTO: o = gco2p(o)->gclist; break;
+      case LUA_VUSERDATA:
+        lua_assert(gco2u(o)->nuvalue > 0);
+        o = gco2u(o)->gclist;
+        break;
+      default: lua_assert(0);  /* other objects cannot be in a gray list */
+    }
+  }
+}
+
+
+/*
+** Check objects in gray lists.
+*/
+static void checkgrays (global_State *g) {
+  if (!keepinvariant(g)) return;
+  checkgraylist(g, g->gray);
+  checkgraylist(g, g->grayagain);
+  checkgraylist(g, g->weak);
+  checkgraylist(g, g->ephemeron);
+}
+
+
+static void checklist (global_State *g, int maybedead, int tof,
+  GCObject *newl, GCObject *survival, GCObject *old, GCObject *reallyold) {
+  GCObject *o;
+  for (o = newl; o != survival; o = o->next) {
+    checkobject(g, o, maybedead, G_NEW);
+    lua_assert(!tof == !tofinalize(o));
+  }
+  for (o = survival; o != old; o = o->next) {
+    checkobject(g, o, 0, G_SURVIVAL);
+    lua_assert(!tof == !tofinalize(o));
+  }
+  for (o = old; o != reallyold; o = o->next) {
+    checkobject(g, o, 0, G_OLD1);
+    lua_assert(!tof == !tofinalize(o));
+  }
+  for (o = reallyold; o != NULL; o = o->next) {
+    checkobject(g, o, 0, G_OLD);
+    lua_assert(!tof == !tofinalize(o));
+  }
+}
+
+
+int lua_checkmemory (lua_State *L) {
+  global_State *g = G(L);
+  GCObject *o;
+  int maybedead;
+  if (keepinvariant(g)) {
+    lua_assert(!iswhite(g->mainthread));
+    lua_assert(!iswhite(gcvalue(&g->l_registry)));
+  }
+  lua_assert(!isdead(g, gcvalue(&g->l_registry)));
+  lua_assert(g->sweepgc == NULL || issweepphase(g));
+  checkgrays(g);
+
+  /* check 'fixedgc' list */
+  for (o = g->fixedgc; o != NULL; o = o->next) {
+    lua_assert(o->tt == LUA_VSHRSTR && isgray(o) && getage(o) == G_OLD);
+  }
+
+  /* check 'allgc' list */
+  maybedead = (GCSatomic < g->gcstate && g->gcstate <= GCSswpallgc);
+  checklist(g, maybedead, 0, g->allgc, g->survival, g->old, g->reallyold);
+
+  /* check 'finobj' list */
+  checklist(g, 0, 1, g->finobj, g->finobjsur, g->finobjold, g->finobjrold);
+
+  /* check 'tobefnz' list */
+  for (o = g->tobefnz; o != NULL; o = o->next) {
+    checkobject(g, o, 0, G_NEW);
+    lua_assert(tofinalize(o));
+    lua_assert(o->tt == LUA_VUSERDATA || o->tt == LUA_VTABLE);
+  }
+  return 0;
+}
+
+/* }====================================================== */
+
+
+
+/*
+** {======================================================
+** Disassembler
+** =======================================================
+*/
+
+
+static char *buildop (Proto *p, int pc, char *buff) {
+  char *obuff = buff;
+  Instruction i = p->code[pc];
+  OpCode o = GET_OPCODE(i);
+  const char *name = opnames[o];
+  int line = luaG_getfuncline(p, pc);
+  int lineinfo = (p->lineinfo != NULL) ? p->lineinfo[pc] : 0;
+  if (lineinfo == ABSLINEINFO)
+    buff += sprintf(buff, "(__");
+  else
+    buff += sprintf(buff, "(%2d", lineinfo);
+  buff += sprintf(buff, " - %4d) %4d - ", line, pc);
+  switch (getOpMode(o)) {
+    case iABC:
+      sprintf(buff, "%-12s%4d %4d %4d%s", name,
+              GETARG_A(i), GETARG_B(i), GETARG_C(i),
+              GETARG_k(i) ? " (k)" : "");
+      break;
+    case iABx:
+      sprintf(buff, "%-12s%4d %4d", name, GETARG_A(i), GETARG_Bx(i));
+      break;
+    case iAsBx:
+      sprintf(buff, "%-12s%4d %4d", name, GETARG_A(i), GETARG_sBx(i));
+      break;
+    case iAx:
+      sprintf(buff, "%-12s%4d", name, GETARG_Ax(i));
+      break;
+    case isJ:
+      sprintf(buff, "%-12s%4d", name, GETARG_sJ(i));
+      break;
+  }
+  return obuff;
+}
+
+
+#if 0
+void luaI_printcode (Proto *pt, int size) {
+  int pc;
+  for (pc=0; pc<size; pc++) {
+    char buff[100];
+    printf("%s\n", buildop(pt, pc, buff));
+  }
+  printf("-------\n");
+}
+
+
+void luaI_printinst (Proto *pt, int pc) {
+  char buff[100];
+  printf("%s\n", buildop(pt, pc, buff));
+}
+#endif
+
+
+static int listcode (lua_State *L) {
+  int pc;
+  Proto *p;
+  luaL_argcheck(L, lua_isfunction(L, 1) && !lua_iscfunction(L, 1),
+                 1, "Lua function expected");
+  p = getproto(obj_at(L, 1));
+  lua_newtable(L);
+  setnameval(L, "maxstack", p->maxstacksize);
+  setnameval(L, "numparams", p->numparams);
+  for (pc=0; pc<p->sizecode; pc++) {
+    char buff[100];
+    lua_pushinteger(L, pc+1);
+    lua_pushstring(L, buildop(p, pc, buff));
+    lua_settable(L, -3);
+  }
+  return 1;
+}
+
+
+static int printcode (lua_State *L) {
+  int pc;
+  Proto *p;
+  luaL_argcheck(L, lua_isfunction(L, 1) && !lua_iscfunction(L, 1),
+                 1, "Lua function expected");
+  p = getproto(obj_at(L, 1));
+  printf("maxstack: %d\n", p->maxstacksize);
+  printf("numparams: %d\n", p->numparams);
+  for (pc=0; pc<p->sizecode; pc++) {
+    char buff[100];
+    printf("%s\n", buildop(p, pc, buff));
+  }
+  return 0;
+}
+
+
+static int listk (lua_State *L) {
+  Proto *p;
+  int i;
+  luaL_argcheck(L, lua_isfunction(L, 1) && !lua_iscfunction(L, 1),
+                 1, "Lua function expected");
+  p = getproto(obj_at(L, 1));
+  lua_createtable(L, p->sizek, 0);
+  for (i=0; i<p->sizek; i++) {
+    pushobject(L, p->k+i);
+    lua_rawseti(L, -2, i+1);
+  }
+  return 1;
+}
+
+
+static int listabslineinfo (lua_State *L) {
+  Proto *p;
+  int i;
+  luaL_argcheck(L, lua_isfunction(L, 1) && !lua_iscfunction(L, 1),
+                 1, "Lua function expected");
+  p = getproto(obj_at(L, 1));
+  luaL_argcheck(L, p->abslineinfo != NULL, 1, "function has no debug info");
+  lua_createtable(L, 2 * p->sizeabslineinfo, 0);
+  for (i=0; i < p->sizeabslineinfo; i++) {
+    lua_pushinteger(L, p->abslineinfo[i].pc);
+    lua_rawseti(L, -2, 2 * i + 1);
+    lua_pushinteger(L, p->abslineinfo[i].line);
+    lua_rawseti(L, -2, 2 * i + 2);
+  }
+  return 1;
+}
+
+
+static int listlocals (lua_State *L) {
+  Proto *p;
+  int pc = cast_int(luaL_checkinteger(L, 2)) - 1;
+  int i = 0;
+  const char *name;
+  luaL_argcheck(L, lua_isfunction(L, 1) && !lua_iscfunction(L, 1),
+                 1, "Lua function expected");
+  p = getproto(obj_at(L, 1));
+  while ((name = luaF_getlocalname(p, ++i, pc)) != NULL)
+    lua_pushstring(L, name);
+  return i-1;
+}
+
+/* }====================================================== */
+
+
+
+static void printstack (lua_State *L) {
+  int i;
+  int n = lua_gettop(L);
+  for (i = 1; i <= n; i++) {
+    printf("%3d: %s\n", i, luaL_tolstring(L, i, NULL));
+    lua_pop(L, 1);
+  }
+  printf("\n");
+}
+
+
+static int get_limits (lua_State *L) {
+  lua_createtable(L, 0, 6);
+  setnameval(L, "IS32INT", LUAI_IS32INT);
+  setnameval(L, "MAXARG_Ax", MAXARG_Ax);
+  setnameval(L, "MAXARG_Bx", MAXARG_Bx);
+  setnameval(L, "OFFSET_sBx", OFFSET_sBx);
+  setnameval(L, "LFPF", LFIELDS_PER_FLUSH);
+  setnameval(L, "NUM_OPCODES", NUM_OPCODES);
+  return 1;
+}
+
+
+static int mem_query (lua_State *L) {
+  if (lua_isnone(L, 1)) {
+    lua_pushinteger(L, l_memcontrol.total);
+    lua_pushinteger(L, l_memcontrol.numblocks);
+    lua_pushinteger(L, l_memcontrol.maxmem);
+    return 3;
+  }
+  else if (lua_isnumber(L, 1)) {
+    unsigned long limit = cast(unsigned long, luaL_checkinteger(L, 1));
+    if (limit == 0) limit = ULONG_MAX;
+    l_memcontrol.memlimit = limit;
+    return 0;
+  }
+  else {
+    const char *t = luaL_checkstring(L, 1);
+    int i;
+    for (i = LUA_NUMTAGS - 1; i >= 0; i--) {
+      if (strcmp(t, ttypename(i)) == 0) {
+        lua_pushinteger(L, l_memcontrol.objcount[i]);
+        return 1;
+      }
+    }
+    return luaL_error(L, "unknown type '%s'", t);
+  }
+}
+
+
+static int alloc_count (lua_State *L) {
+  if (lua_isnone(L, 1))
+    l_memcontrol.countlimit = ~0L;
+  else
+    l_memcontrol.countlimit = luaL_checkinteger(L, 1);
+  return 0;
+}
+  
+
+static int settrick (lua_State *L) {
+  if (ttisnil(obj_at(L, 1)))
+    l_Trick = NULL;
+  else
+    l_Trick = gcvalue(obj_at(L, 1));
+  return 0;
+}
+
+
+static int gc_color (lua_State *L) {
+  TValue *o;
+  luaL_checkany(L, 1);
+  o = obj_at(L, 1);
+  if (!iscollectable(o))
+    lua_pushstring(L, "no collectable");
+  else {
+    GCObject *obj = gcvalue(o);
+    lua_pushstring(L, isdead(G(L), obj) ? "dead" :
+                      iswhite(obj) ? "white" :
+                      isblack(obj) ? "black" : "gray");
+  }
+  return 1;
+}
+
+
+static int gc_age (lua_State *L) {
+  TValue *o;
+  luaL_checkany(L, 1);
+  o = obj_at(L, 1);
+  if (!iscollectable(o))
+    lua_pushstring(L, "no collectable");
+  else {
+    static const char *gennames[] = {"new", "survival", "old0", "old1",
+                                     "old", "touched1", "touched2"};
+    GCObject *obj = gcvalue(o);
+    lua_pushstring(L, gennames[getage(obj)]);
+  }
+  return 1;
+}
+
+
+static int gc_printobj (lua_State *L) {
+  TValue *o;
+  luaL_checkany(L, 1);
+  o = obj_at(L, 1);
+  if (!iscollectable(o))
+    printf("no collectable\n");
+  else {
+    GCObject *obj = gcvalue(o);
+    printobj(G(L), obj);
+    printf("\n");
+  }
+  return 0;
+}
+
+
+static int gc_state (lua_State *L) {
+  static const char *statenames[] = {
+    "propagate", "atomic", "enteratomic", "sweepallgc", "sweepfinobj",
+    "sweeptobefnz", "sweepend", "callfin", "pause", ""};
+  static const int states[] = {
+    GCSpropagate, GCSenteratomic, GCSatomic, GCSswpallgc, GCSswpfinobj,
+    GCSswptobefnz, GCSswpend, GCScallfin, GCSpause, -1};
+  int option = states[luaL_checkoption(L, 1, "", statenames)];
+  if (option == -1) {
+    lua_pushstring(L, statenames[G(L)->gcstate]);
+    return 1;
+  }
+  else {
+    global_State *g = G(L);
+    if (G(L)->gckind == KGC_GEN)
+      luaL_error(L, "cannot change states in generational mode");
+    lua_lock(L);
+    if (option < g->gcstate) {  /* must cross 'pause'? */
+      luaC_runtilstate(L, bitmask(GCSpause));  /* run until pause */
+    }
+    luaC_runtilstate(L, bitmask(option));
+    lua_assert(G(L)->gcstate == option);
+    lua_unlock(L);
+    return 0;
+  }
+}
+
+
+static int hash_query (lua_State *L) {
+  if (lua_isnone(L, 2)) {
+    luaL_argcheck(L, lua_type(L, 1) == LUA_TSTRING, 1, "string expected");
+    lua_pushinteger(L, tsvalue(obj_at(L, 1))->hash);
+  }
+  else {
+    TValue *o = obj_at(L, 1);
+    Table *t;
+    luaL_checktype(L, 2, LUA_TTABLE);
+    t = hvalue(obj_at(L, 2));
+    lua_pushinteger(L, luaH_mainposition(t, o) - t->node);
+  }
+  return 1;
+}
+
+
+static int stacklevel (lua_State *L) {
+  unsigned long a = 0;
+  lua_pushinteger(L, (L->top - L->stack));
+  lua_pushinteger(L, (L->stack_last - L->stack));
+  lua_pushinteger(L, L->nCcalls);
+  lua_pushinteger(L, L->nci);
+  lua_pushinteger(L, (unsigned long)&a);
+  return 5;
+}
+
+
+static int table_query (lua_State *L) {
+  const Table *t;
+  int i = cast_int(luaL_optinteger(L, 2, -1));
+  unsigned int asize;
+  luaL_checktype(L, 1, LUA_TTABLE);
+  t = hvalue(obj_at(L, 1));
+  asize = luaH_realasize(t);
+  if (i == -1) {
+    lua_pushinteger(L, asize);
+    lua_pushinteger(L, allocsizenode(t));
+    lua_pushinteger(L, isdummy(t) ? 0 : t->lastfree - t->node);
+    lua_pushinteger(L, t->alimit);
+    return 4;
+  }
+  else if ((unsigned int)i < asize) {
+    lua_pushinteger(L, i);
+    pushobject(L, &t->array[i]);
+    lua_pushnil(L);
+  }
+  else if ((i -= asize) < sizenode(t)) {
+    TValue k;
+    getnodekey(L, &k, gnode(t, i));
+    if (!isempty(gval(gnode(t, i))) ||
+        ttisnil(&k) ||
+        ttisnumber(&k)) {
+      pushobject(L, &k);
+    }
+    else
+      lua_pushliteral(L, "<undef>");
+    pushobject(L, gval(gnode(t, i)));
+    if (gnext(&t->node[i]) != 0)
+      lua_pushinteger(L, gnext(&t->node[i]));
+    else
+      lua_pushnil(L);
+  }
+  return 3;
+}
+
+
+static int string_query (lua_State *L) {
+  stringtable *tb = &G(L)->strt;
+  int s = cast_int(luaL_optinteger(L, 1, 0)) - 1;
+  if (s == -1) {
+    lua_pushinteger(L ,tb->size);
+    lua_pushinteger(L ,tb->nuse);
+    return 2;
+  }
+  else if (s < tb->size) {
+    TString *ts;
+    int n = 0;
+    for (ts = tb->hash[s]; ts != NULL; ts = ts->u.hnext) {
+      setsvalue2s(L, L->top, ts);
+      api_incr_top(L);
+      n++;
+    }
+    return n;
+  }
+  else return 0;
+}
+
+
+static int tref (lua_State *L) {
+  int level = lua_gettop(L);
+  luaL_checkany(L, 1);
+  lua_pushvalue(L, 1);
+  lua_pushinteger(L, luaL_ref(L, LUA_REGISTRYINDEX));
+  lua_assert(lua_gettop(L) == level+1);  /* +1 for result */
+  return 1;
+}
+
+static int getref (lua_State *L) {
+  int level = lua_gettop(L);
+  lua_rawgeti(L, LUA_REGISTRYINDEX, luaL_checkinteger(L, 1));
+  lua_assert(lua_gettop(L) == level+1);
+  return 1;
+}
+
+static int unref (lua_State *L) {
+  int level = lua_gettop(L);
+  luaL_unref(L, LUA_REGISTRYINDEX, cast_int(luaL_checkinteger(L, 1)));
+  lua_assert(lua_gettop(L) == level);
+  return 0;
+}
+
+
+static int upvalue (lua_State *L) {
+  int n = cast_int(luaL_checkinteger(L, 2));
+  luaL_checktype(L, 1, LUA_TFUNCTION);
+  if (lua_isnone(L, 3)) {
+    const char *name = lua_getupvalue(L, 1, n);
+    if (name == NULL) return 0;
+    lua_pushstring(L, name);
+    return 2;
+  }
+  else {
+    const char *name = lua_setupvalue(L, 1, n);
+    lua_pushstring(L, name);
+    return 1;
+  }
+}
+
+
+static int newuserdata (lua_State *L) {
+  size_t size = cast_sizet(luaL_optinteger(L, 1, 0));
+  int nuv = luaL_optinteger(L, 2, 0);
+  char *p = cast_charp(lua_newuserdatauv(L, size, nuv));
+  while (size--) *p++ = '\0';
+  return 1;
+}
+
+
+static int pushuserdata (lua_State *L) {
+  lua_Integer u = luaL_checkinteger(L, 1);
+  lua_pushlightuserdata(L, cast_voidp(cast_sizet(u)));
+  return 1;
+}
+
+
+static int udataval (lua_State *L) {
+  lua_pushinteger(L, cast(long, lua_touserdata(L, 1)));
+  return 1;
+}
+
+
+static int doonnewstack (lua_State *L) {
+  lua_State *L1 = lua_newthread(L);
+  size_t l;
+  const char *s = luaL_checklstring(L, 1, &l);
+  int status = luaL_loadbuffer(L1, s, l, s);
+  if (status == LUA_OK)
+    status = lua_pcall(L1, 0, 0, 0);
+  lua_pushinteger(L, status);
+  return 1;
+}
+
+
+static int s2d (lua_State *L) {
+  lua_pushnumber(L, cast_num(*cast(const double *, luaL_checkstring(L, 1))));
+  return 1;
+}
+
+
+static int d2s (lua_State *L) {
+  double d = cast(double, luaL_checknumber(L, 1));
+  lua_pushlstring(L, cast_charp(&d), sizeof(d));
+  return 1;
+}
+
+
+static int num2int (lua_State *L) {
+  lua_pushinteger(L, lua_tointeger(L, 1));
+  return 1;
+}
+
+
+static int newstate (lua_State *L) {
+  void *ud;
+  lua_Alloc f = lua_getallocf(L, &ud);
+  lua_State *L1 = lua_newstate(f, ud);
+  if (L1) {
+    lua_atpanic(L1, tpanic);
+    lua_pushlightuserdata(L, L1);
+  }
+  else
+    lua_pushnil(L);
+  return 1;
+}
+
+
+static lua_State *getstate (lua_State *L) {
+  lua_State *L1 = cast(lua_State *, lua_touserdata(L, 1));
+  luaL_argcheck(L, L1 != NULL, 1, "state expected");
+  return L1;
+}
+
+
+static int loadlib (lua_State *L) {
+  static const luaL_Reg libs[] = {
+    {LUA_GNAME, luaopen_base},
+    {"coroutine", luaopen_coroutine},
+    {"debug", luaopen_debug},
+    {"io", luaopen_io},
+    {"os", luaopen_os},
+    {"math", luaopen_math},
+    {"string", luaopen_string},
+    {"table", luaopen_table},
+    {"T", luaB_opentests},
+    {NULL, NULL}
+  };
+  lua_State *L1 = getstate(L);
+  int i;
+  luaL_requiref(L1, "package", luaopen_package, 0);
+  lua_assert(lua_type(L1, -1) == LUA_TTABLE);
+  /* 'requiref' should not reload module already loaded... */
+  luaL_requiref(L1, "package", NULL, 1);  /* seg. fault if it reloads */
+  /* ...but should return the same module */
+  lua_assert(lua_compare(L1, -1, -2, LUA_OPEQ));
+  luaL_getsubtable(L1, LUA_REGISTRYINDEX, LUA_PRELOAD_TABLE);
+  for (i = 0; libs[i].name; i++) {
+    lua_pushcfunction(L1, libs[i].func);
+    lua_setfield(L1, -2, libs[i].name);
+  }
+  return 0;
+}
+
+static int closestate (lua_State *L) {
+  lua_State *L1 = getstate(L);
+  lua_close(L1);
+  return 0;
+}
+
+static int doremote (lua_State *L) {
+  lua_State *L1 = getstate(L);
+  size_t lcode;
+  const char *code = luaL_checklstring(L, 2, &lcode);
+  int status;
+  lua_settop(L1, 0);
+  status = luaL_loadbuffer(L1, code, lcode, code);
+  if (status == LUA_OK)
+    status = lua_pcall(L1, 0, LUA_MULTRET, 0);
+  if (status != LUA_OK) {
+    lua_pushnil(L);
+    lua_pushstring(L, lua_tostring(L1, -1));
+    lua_pushinteger(L, status);
+    return 3;
+  }
+  else {
+    int i = 0;
+    while (!lua_isnone(L1, ++i))
+      lua_pushstring(L, lua_tostring(L1, i));
+    lua_pop(L1, i-1);
+    return i-1;
+  }
+}
+
+
+static int log2_aux (lua_State *L) {
+  unsigned int x = (unsigned int)luaL_checkinteger(L, 1);
+  lua_pushinteger(L, luaO_ceillog2(x));
+  return 1;
+}
+
+
+struct Aux { jmp_buf jb; const char *paniccode; lua_State *L; };
+
+/*
+** does a long-jump back to "main program".
+*/
+static int panicback (lua_State *L) {
+  struct Aux *b;
+  lua_checkstack(L, 1);  /* open space for 'Aux' struct */
+  lua_getfield(L, LUA_REGISTRYINDEX, "_jmpbuf");  /* get 'Aux' struct */
+  b = (struct Aux *)lua_touserdata(L, -1);
+  lua_pop(L, 1);  /* remove 'Aux' struct */
+  runC(b->L, L, b->paniccode);  /* run optional panic code */
+  longjmp(b->jb, 1);
+  return 1;  /* to avoid warnings */
+}
+
+static int checkpanic (lua_State *L) {
+  struct Aux b;
+  void *ud;
+  lua_State *L1;
+  const char *code = luaL_checkstring(L, 1);
+  lua_Alloc f = lua_getallocf(L, &ud);
+  b.paniccode = luaL_optstring(L, 2, "");
+  b.L = L;
+  L1 = lua_newstate(f, ud);  /* create new state */
+  if (L1 == NULL) {  /* error? */
+    lua_pushnil(L);
+    return 1;
+  }
+  lua_atpanic(L1, panicback);  /* set its panic function */
+  lua_pushlightuserdata(L1, &b);
+  lua_setfield(L1, LUA_REGISTRYINDEX, "_jmpbuf");  /* store 'Aux' struct */
+  if (setjmp(b.jb) == 0) {  /* set jump buffer */
+    runC(L, L1, code);  /* run code unprotected */
+    lua_pushliteral(L, "no errors");
+  }
+  else {  /* error handling */
+    /* move error message to original state */
+    lua_pushstring(L, lua_tostring(L1, -1));
+  }
+  lua_close(L1);
+  return 1;
+}
+
+
+
+/*
+** {====================================================================
+** function to test the API with C. It interprets a kind of assembler
+** language with calls to the API, so the test can be driven by Lua code
+** =====================================================================
+*/
+
+
+static void sethookaux (lua_State *L, int mask, int count, const char *code);
+
+static const char *const delimits = " \t\n,;";
+
+static void skip (const char **pc) {
+  for (;;) {
+    if (**pc != '\0' && strchr(delimits, **pc)) (*pc)++;
+    else if (**pc == '#') {  /* comment? */
+      while (**pc != '\n' && **pc != '\0') (*pc)++;  /* until end-of-line */
+    }
+    else break;
+  }
+}
+
+static int getnum_aux (lua_State *L, lua_State *L1, const char **pc) {
+  int res = 0;
+  int sig = 1;
+  skip(pc);
+  if (**pc == '.') {
+    res = cast_int(lua_tointeger(L1, -1));
+    lua_pop(L1, 1);
+    (*pc)++;
+    return res;
+  }
+  else if (**pc == '*') {
+    res = lua_gettop(L1);
+    (*pc)++;
+    return res;
+  }
+  else if (**pc == '-') {
+    sig = -1;
+    (*pc)++;
+  }
+  if (!lisdigit(cast_uchar(**pc)))
+    luaL_error(L, "number expected (%s)", *pc);
+  while (lisdigit(cast_uchar(**pc))) res = res*10 + (*(*pc)++) - '0';
+  return sig*res;
+}
+
+static const char *getstring_aux (lua_State *L, char *buff, const char **pc) {
+  int i = 0;
+  skip(pc);
+  if (**pc == '"' || **pc == '\'') {  /* quoted string? */
+    int quote = *(*pc)++;
+    while (**pc != quote) {
+      if (**pc == '\0') luaL_error(L, "unfinished string in C script");
+      buff[i++] = *(*pc)++;
+    }
+    (*pc)++;
+  }
+  else {
+    while (**pc != '\0' && !strchr(delimits, **pc))
+      buff[i++] = *(*pc)++;
+  }
+  buff[i] = '\0';
+  return buff;
+}
+
+
+static int getindex_aux (lua_State *L, lua_State *L1, const char **pc) {
+  skip(pc);
+  switch (*(*pc)++) {
+    case 'R': return LUA_REGISTRYINDEX;
+    case 'G': return luaL_error(L, "deprecated index 'G'");
+    case 'U': return lua_upvalueindex(getnum_aux(L, L1, pc));
+    default: (*pc)--; return getnum_aux(L, L1, pc);
+  }
+}
+
+
+static void pushcode (lua_State *L, int code) {
+  static const char *const codes[] = {"OK", "YIELD", "ERRRUN",
+                   "ERRSYNTAX", MEMERRMSG, "ERRGCMM", "ERRERR"};
+  lua_pushstring(L, codes[code]);
+}
+
+
+#define EQ(s1)	(strcmp(s1, inst) == 0)
+
+#define getnum		(getnum_aux(L, L1, &pc))
+#define getstring	(getstring_aux(L, buff, &pc))
+#define getindex	(getindex_aux(L, L1, &pc))
+
+
+static int testC (lua_State *L);
+static int Cfunck (lua_State *L, int status, lua_KContext ctx);
+
+/*
+** arithmetic operation encoding for 'arith' instruction
+** LUA_OPIDIV  -> \
+** LUA_OPSHL   -> <
+** LUA_OPSHR   -> >
+** LUA_OPUNM   -> _
+** LUA_OPBNOT  -> !
+*/
+static const char ops[] = "+-*%^/\\&|~<>_!";
+
+static int runC (lua_State *L, lua_State *L1, const char *pc) {
+  char buff[300];
+  int status = 0;
+  if (pc == NULL) return luaL_error(L, "attempt to runC null script");
+  for (;;) {
+    const char *inst = getstring;
+    if EQ("") return 0;
+    else if EQ("absindex") {
+      lua_pushnumber(L1, lua_absindex(L1, getindex));
+    }
+    else if EQ("append") {
+      int t = getindex;
+      int i = lua_rawlen(L1, t);
+      lua_rawseti(L1, t, i + 1);
+    }
+    else if EQ("arith") {
+      int op;
+      skip(&pc);
+      op = strchr(ops, *pc++) - ops;
+      lua_arith(L1, op);
+    }
+    else if EQ("call") {
+      int narg = getnum;
+      int nres = getnum;
+      lua_call(L1, narg, nres);
+    }
+    else if EQ("callk") {
+      int narg = getnum;
+      int nres = getnum;
+      int i = getindex;
+      lua_callk(L1, narg, nres, i, Cfunck);
+    }
+    else if EQ("checkstack") {
+      int sz = getnum;
+      const char *msg = getstring;
+      if (*msg == '\0')
+        msg = NULL;  /* to test 'luaL_checkstack' with no message */
+      luaL_checkstack(L1, sz, msg);
+    }
+    else if EQ("rawcheckstack") {
+      int sz = getnum;
+      lua_pushboolean(L1, lua_checkstack(L1, sz));
+    }
+    else if EQ("compare") {
+      const char *opt = getstring;  /* EQ, LT, or LE */
+      int op = (opt[0] == 'E') ? LUA_OPEQ
+                               : (opt[1] == 'T') ? LUA_OPLT : LUA_OPLE;
+      int a = getindex;
+      int b = getindex;
+      lua_pushboolean(L1, lua_compare(L1, a, b, op));
+    }
+    else if EQ("concat") {
+      lua_concat(L1, getnum);
+    }
+    else if EQ("copy") {
+      int f = getindex;
+      lua_copy(L1, f, getindex);
+    }
+    else if EQ("func2num") {
+      lua_CFunction func = lua_tocfunction(L1, getindex);
+      lua_pushnumber(L1, cast_sizet(func));
+    }
+    else if EQ("getfield") {
+      int t = getindex;
+      lua_getfield(L1, t, getstring);
+    }
+    else if EQ("getglobal") {
+      lua_getglobal(L1, getstring);
+    }
+    else if EQ("getmetatable") {
+      if (lua_getmetatable(L1, getindex) == 0)
+        lua_pushnil(L1);
+    }
+    else if EQ("gettable") {
+      lua_gettable(L1, getindex);
+    }
+    else if EQ("gettop") {
+      lua_pushinteger(L1, lua_gettop(L1));
+    }
+    else if EQ("gsub") {
+      int a = getnum; int b = getnum; int c = getnum;
+      luaL_gsub(L1, lua_tostring(L1, a),
+                    lua_tostring(L1, b),
+                    lua_tostring(L1, c));
+    }
+    else if EQ("insert") {
+      lua_insert(L1, getnum);
+    }
+    else if EQ("iscfunction") {
+      lua_pushboolean(L1, lua_iscfunction(L1, getindex));
+    }
+    else if EQ("isfunction") {
+      lua_pushboolean(L1, lua_isfunction(L1, getindex));
+    }
+    else if EQ("isnil") {
+      lua_pushboolean(L1, lua_isnil(L1, getindex));
+    }
+    else if EQ("isnull") {
+      lua_pushboolean(L1, lua_isnone(L1, getindex));
+    }
+    else if EQ("isnumber") {
+      lua_pushboolean(L1, lua_isnumber(L1, getindex));
+    }
+    else if EQ("isstring") {
+      lua_pushboolean(L1, lua_isstring(L1, getindex));
+    }
+    else if EQ("istable") {
+      lua_pushboolean(L1, lua_istable(L1, getindex));
+    }
+    else if EQ("isudataval") {
+      lua_pushboolean(L1, lua_islightuserdata(L1, getindex));
+    }
+    else if EQ("isuserdata") {
+      lua_pushboolean(L1, lua_isuserdata(L1, getindex));
+    }
+    else if EQ("len") {
+      lua_len(L1, getindex);
+    }
+    else if EQ("Llen") {
+      lua_pushinteger(L1, luaL_len(L1, getindex));
+    }
+    else if EQ("loadfile") {
+      luaL_loadfile(L1, luaL_checkstring(L1, getnum));
+    }
+    else if EQ("loadstring") {
+      const char *s = luaL_checkstring(L1, getnum);
+      luaL_loadstring(L1, s);
+    }
+    else if EQ("newmetatable") {
+      lua_pushboolean(L1, luaL_newmetatable(L1, getstring));
+    }
+    else if EQ("newtable") {
+      lua_newtable(L1);
+    }
+    else if EQ("newthread") {
+      lua_newthread(L1);
+    }
+    else if EQ("resetthread") {
+      lua_pushinteger(L1, lua_resetthread(L1));
+    }
+    else if EQ("newuserdata") {
+      lua_newuserdata(L1, getnum);
+    }
+    else if EQ("next") {
+      lua_next(L1, -2);
+    }
+    else if EQ("objsize") {
+      lua_pushinteger(L1, lua_rawlen(L1, getindex));
+    }
+    else if EQ("pcall") {
+      int narg = getnum;
+      int nres = getnum;
+      status = lua_pcall(L1, narg, nres, getnum);
+    }
+    else if EQ("pcallk") {
+      int narg = getnum;
+      int nres = getnum;
+      int i = getindex;
+      status = lua_pcallk(L1, narg, nres, 0, i, Cfunck);
+    }
+    else if EQ("pop") {
+      lua_pop(L1, getnum);
+    }
+    else if EQ("printstack") {
+      int n = getnum;
+      if (n != 0) {
+        printf("%s\n", luaL_tolstring(L1, n, NULL));
+        lua_pop(L1, 1);
+      }
+      else printstack(L1);
+    }
+    else if EQ("print") {
+      const char *msg = getstring;
+      printf("%s\n", msg);
+    }
+    else if EQ("warningC") {
+      const char *msg = getstring;
+      lua_warning(L1, msg, 1);
+    }
+    else if EQ("warning") {
+      const char *msg = getstring;
+      lua_warning(L1, msg, 0);
+    }
+    else if EQ("pushbool") {
+      lua_pushboolean(L1, getnum);
+    }
+    else if EQ("pushcclosure") {
+      lua_pushcclosure(L1, testC, getnum);
+    }
+    else if EQ("pushint") {
+      lua_pushinteger(L1, getnum);
+    }
+    else if EQ("pushnil") {
+      lua_pushnil(L1);
+    }
+    else if EQ("pushnum") {
+      lua_pushnumber(L1, (lua_Number)getnum);
+    }
+    else if EQ("pushstatus") {
+      pushcode(L1, status);
+    }
+    else if EQ("pushstring") {
+      lua_pushstring(L1, getstring);
+    }
+    else if EQ("pushupvalueindex") {
+      lua_pushinteger(L1, lua_upvalueindex(getnum));
+    }
+    else if EQ("pushvalue") {
+      lua_pushvalue(L1, getindex);
+    }
+    else if EQ("pushfstringI") {
+      lua_pushfstring(L1, lua_tostring(L, -2), (int)lua_tointeger(L, -1));
+    }
+    else if EQ("pushfstringS") {
+      lua_pushfstring(L1, lua_tostring(L, -2), lua_tostring(L, -1));
+    }
+    else if EQ("pushfstringP") {
+      lua_pushfstring(L1, lua_tostring(L, -2), lua_topointer(L, -1));
+    }
+    else if EQ("rawget") {
+      int t = getindex;
+      lua_rawget(L1, t);
+    }
+    else if EQ("rawgeti") {
+      int t = getindex;
+      lua_rawgeti(L1, t, getnum);
+    }
+    else if EQ("rawgetp") {
+      int t = getindex;
+      lua_rawgetp(L1, t, cast_voidp(cast_sizet(getnum)));
+    }
+    else if EQ("rawset") {
+      int t = getindex;
+      lua_rawset(L1, t);
+    }
+    else if EQ("rawseti") {
+      int t = getindex;
+      lua_rawseti(L1, t, getnum);
+    }
+    else if EQ("rawsetp") {
+      int t = getindex;
+      lua_rawsetp(L1, t, cast_voidp(cast_sizet(getnum)));
+    }
+    else if EQ("remove") {
+      lua_remove(L1, getnum);
+    }
+    else if EQ("replace") {
+      lua_replace(L1, getindex);
+    }
+    else if EQ("resume") {
+      int i = getindex;
+      int nres;
+      status = lua_resume(lua_tothread(L1, i), L, getnum, &nres);
+    }
+    else if EQ("return") {
+      int n = getnum;
+      if (L1 != L) {
+        int i;
+        for (i = 0; i < n; i++) {
+          int idx = -(n - i);
+          switch (lua_type(L1, idx)) {
+            case LUA_TBOOLEAN:
+              lua_pushboolean(L, lua_toboolean(L1, idx));
+              break;
+            default:
+              lua_pushstring(L, lua_tostring(L1, idx));
+              break;
+          }
+        }
+      }
+      return n;
+    }
+    else if EQ("rotate") {
+      int i = getindex;
+      lua_rotate(L1, i, getnum);
+    }
+    else if EQ("setfield") {
+      int t = getindex;
+      const char *s = getstring;
+      lua_setfield(L1, t, s);
+    }
+    else if EQ("seti") {
+      int t = getindex;
+      lua_seti(L1, t, getnum);
+    }
+    else if EQ("setglobal") {
+      const char *s = getstring;
+      lua_setglobal(L1, s);
+    }
+    else if EQ("sethook") {
+      int mask = getnum;
+      int count = getnum;
+      const char *s = getstring;
+      sethookaux(L1, mask, count, s);
+    }
+    else if EQ("setmetatable") {
+      int idx = getindex;
+      lua_setmetatable(L1, idx);
+    }
+    else if EQ("settable") {
+      lua_settable(L1, getindex);
+    }
+    else if EQ("settop") {
+      lua_settop(L1, getnum);
+    }
+    else if EQ("testudata") {
+      int i = getindex;
+      lua_pushboolean(L1, luaL_testudata(L1, i, getstring) != NULL);
+    }
+    else if EQ("error") {
+      lua_error(L1);
+    }
+    else if EQ("abort") {
+      abort();
+    }
+    else if EQ("throw") {
+#if defined(__cplusplus)
+static struct X { int x; } x;
+      throw x;
+#else
+      luaL_error(L1, "C++");
+#endif
+      break;
+    }
+    else if EQ("tobool") {
+      lua_pushboolean(L1, lua_toboolean(L1, getindex));
+    }
+    else if EQ("tocfunction") {
+      lua_pushcfunction(L1, lua_tocfunction(L1, getindex));
+    }
+    else if EQ("tointeger") {
+      lua_pushinteger(L1, lua_tointeger(L1, getindex));
+    }
+    else if EQ("tonumber") {
+      lua_pushnumber(L1, lua_tonumber(L1, getindex));
+    }
+    else if EQ("topointer") {
+      lua_pushlightuserdata(L1, cast_voidp(lua_topointer(L1, getindex)));
+    }
+    else if EQ("touserdata") {
+      lua_pushlightuserdata(L1, lua_touserdata(L1, getindex));
+    }
+    else if EQ("tostring") {
+      const char *s = lua_tostring(L1, getindex);
+      const char *s1 = lua_pushstring(L1, s);
+      lua_longassert((s == NULL && s1 == NULL) || strcmp(s, s1) == 0);
+    }
+    else if EQ("type") {
+      lua_pushstring(L1, luaL_typename(L1, getnum));
+    }
+    else if EQ("xmove") {
+      int f = getindex;
+      int t = getindex;
+      lua_State *fs = (f == 0) ? L1 : lua_tothread(L1, f);
+      lua_State *ts = (t == 0) ? L1 : lua_tothread(L1, t);
+      int n = getnum;
+      if (n == 0) n = lua_gettop(fs);
+      lua_xmove(fs, ts, n);
+    }
+    else if EQ("yield") {
+      return lua_yield(L1, getnum);
+    }
+    else if EQ("yieldk") {
+      int nres = getnum;
+      int i = getindex;
+      return lua_yieldk(L1, nres, i, Cfunck);
+    }
+    else if EQ("toclose") {
+      lua_toclose(L1, getnum);
+    }
+    else luaL_error(L, "unknown instruction %s", buff);
+  }
+  return 0;
+}
+
+
+static int testC (lua_State *L) {
+  lua_State *L1;
+  const char *pc;
+  if (lua_isuserdata(L, 1)) {
+    L1 = getstate(L);
+    pc = luaL_checkstring(L, 2);
+  }
+  else if (lua_isthread(L, 1)) {
+    L1 = lua_tothread(L, 1);
+    pc = luaL_checkstring(L, 2);
+  }
+  else {
+    L1 = L;
+    pc = luaL_checkstring(L, 1);
+  }
+  return runC(L, L1, pc);
+}
+
+
+static int Cfunc (lua_State *L) {
+  return runC(L, L, lua_tostring(L, lua_upvalueindex(1)));
+}
+
+
+static int Cfunck (lua_State *L, int status, lua_KContext ctx) {
+  pushcode(L, status);
+  lua_setglobal(L, "status");
+  lua_pushinteger(L, ctx);
+  lua_setglobal(L, "ctx");
+  return runC(L, L, lua_tostring(L, ctx));
+}
+
+
+static int makeCfunc (lua_State *L) {
+  luaL_checkstring(L, 1);
+  lua_pushcclosure(L, Cfunc, lua_gettop(L));
+  return 1;
+}
+
+
+/* }====================================================== */
+
+
+/*
+** {======================================================
+** tests for C hooks
+** =======================================================
+*/
+
+/*
+** C hook that runs the C script stored in registry.C_HOOK[L]
+*/
+static void Chook (lua_State *L, lua_Debug *ar) {
+  const char *scpt;
+  const char *const events [] = {"call", "ret", "line", "count", "tailcall"};
+  lua_getfield(L, LUA_REGISTRYINDEX, "C_HOOK");
+  lua_pushlightuserdata(L, L);
+  lua_gettable(L, -2);  /* get C_HOOK[L] (script saved by sethookaux) */
+  scpt = lua_tostring(L, -1);  /* not very religious (string will be popped) */
+  lua_pop(L, 2);  /* remove C_HOOK and script */
+  lua_pushstring(L, events[ar->event]);  /* may be used by script */
+  lua_pushinteger(L, ar->currentline);  /* may be used by script */
+  runC(L, L, scpt);  /* run script from C_HOOK[L] */
+}
+
+
+/*
+** sets 'registry.C_HOOK[L] = scpt' and sets 'Chook' as a hook
+*/
+static void sethookaux (lua_State *L, int mask, int count, const char *scpt) {
+  if (*scpt == '\0') {  /* no script? */
+    lua_sethook(L, NULL, 0, 0);  /* turn off hooks */
+    return;
+  }
+  lua_getfield(L, LUA_REGISTRYINDEX, "C_HOOK");  /* get C_HOOK table */
+  if (!lua_istable(L, -1)) {  /* no hook table? */
+    lua_pop(L, 1);  /* remove previous value */
+    lua_newtable(L);  /* create new C_HOOK table */
+    lua_pushvalue(L, -1);
+    lua_setfield(L, LUA_REGISTRYINDEX, "C_HOOK");  /* register it */
+  }
+  lua_pushlightuserdata(L, L);
+  lua_pushstring(L, scpt);
+  lua_settable(L, -3);  /* C_HOOK[L] = script */
+  lua_sethook(L, Chook, mask, count);
+}
+
+
+static int sethook (lua_State *L) {
+  if (lua_isnoneornil(L, 1))
+    lua_sethook(L, NULL, 0, 0);  /* turn off hooks */
+  else {
+    const char *scpt = luaL_checkstring(L, 1);
+    const char *smask = luaL_checkstring(L, 2);
+    int count = cast_int(luaL_optinteger(L, 3, 0));
+    int mask = 0;
+    if (strchr(smask, 'c')) mask |= LUA_MASKCALL;
+    if (strchr(smask, 'r')) mask |= LUA_MASKRET;
+    if (strchr(smask, 'l')) mask |= LUA_MASKLINE;
+    if (count > 0) mask |= LUA_MASKCOUNT;
+    sethookaux(L, mask, count, scpt);
+  }
+  return 0;
+}
+
+
+static int coresume (lua_State *L) {
+  int status, nres;
+  lua_State *co = lua_tothread(L, 1);
+  luaL_argcheck(L, co, 1, "coroutine expected");
+  status = lua_resume(co, L, 0, &nres);
+  if (status != LUA_OK && status != LUA_YIELD) {
+    lua_pushboolean(L, 0);
+    lua_insert(L, -2);
+    return 2;  /* return false + error message */
+  }
+  else {
+    lua_pushboolean(L, 1);
+    return 1;
+  }
+}
+
+/* }====================================================== */
+
+
+
+static const struct luaL_Reg tests_funcs[] = {
+  {"checkmemory", lua_checkmemory},
+  {"closestate", closestate},
+  {"d2s", d2s},
+  {"doonnewstack", doonnewstack},
+  {"doremote", doremote},
+  {"gccolor", gc_color},
+  {"gcage", gc_age},
+  {"gcstate", gc_state},
+  {"pobj", gc_printobj},
+  {"getref", getref},
+  {"hash", hash_query},
+  {"log2", log2_aux},
+  {"limits", get_limits},
+  {"listcode", listcode},
+  {"printcode", printcode},
+  {"listk", listk},
+  {"listabslineinfo", listabslineinfo},
+  {"listlocals", listlocals},
+  {"loadlib", loadlib},
+  {"checkpanic", checkpanic},
+  {"newstate", newstate},
+  {"newuserdata", newuserdata},
+  {"num2int", num2int},
+  {"pushuserdata", pushuserdata},
+  {"querystr", string_query},
+  {"querytab", table_query},
+  {"ref", tref},
+  {"resume", coresume},
+  {"s2d", s2d},
+  {"sethook", sethook},
+  {"stacklevel", stacklevel},
+  {"testC", testC},
+  {"makeCfunc", makeCfunc},
+  {"totalmem", mem_query},
+  {"alloccount", alloc_count},
+  {"trick", settrick},
+  {"udataval", udataval},
+  {"unref", unref},
+  {"upvalue", upvalue},
+  {NULL, NULL}
+};
+
+
+static void checkfinalmem (void) {
+  lua_assert(l_memcontrol.numblocks == 0);
+  lua_assert(l_memcontrol.total == 0);
+}
+
+
+int luaB_opentests (lua_State *L) {
+  void *ud;
+  lua_atpanic(L, &tpanic);
+  lua_setwarnf(L, &warnf, L);
+  atexit(checkfinalmem);
+  lua_assert(lua_getallocf(L, &ud) == debug_realloc);
+  lua_assert(ud == cast_voidp(&l_memcontrol));
+  lua_setallocf(L, lua_getallocf(L, NULL), ud);
+  luaL_newlib(L, tests_funcs);
+  return 1;
+}
+
+#endif
+
diff --git a/test/external/lua-5.4.0-tests/ltests/ltests.h b/test/external/lua-5.4.0-tests/ltests/ltests.h
new file mode 100644
index 0000000..02331eb
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/ltests/ltests.h
@@ -0,0 +1,139 @@
+/*
+** $Id: ltests.h $
+** Internal Header for Debugging of the Lua Implementation
+** See Copyright Notice in lua.h
+*/
+
+#ifndef ltests_h
+#define ltests_h
+
+
+#include <stdio.h>
+#include <stdlib.h>
+
+/* test Lua with compatibility code */
+#define LUA_COMPAT_MATHLIB
+#define LUA_COMPAT_LT_LE
+
+
+#define LUA_DEBUG
+
+
+/* turn on assertions */
+#undef NDEBUG
+#include <assert.h>
+#define lua_assert(c)           assert(c)
+
+
+
+/* compiled with -O0, Lua uses a lot of C stack space... */
+#undef LUAI_MAXCSTACK
+#define LUAI_MAXCSTACK		400
+
+/* to avoid warnings, and to make sure value is really unused */
+#define UNUSED(x)       (x=0, (void)(x))
+
+
+/* test for sizes in 'l_sprintf' (make sure whole buffer is available) */
+#undef l_sprintf
+#if !defined(LUA_USE_C89)
+#define l_sprintf(s,sz,f,i)	(memset(s,0xAB,sz), snprintf(s,sz,f,i))
+#else
+#define l_sprintf(s,sz,f,i)	(memset(s,0xAB,sz), sprintf(s,f,i))
+#endif
+
+
+/* get a chance to test code without jump tables */
+#define LUA_USE_JUMPTABLE	0
+
+
+/* use 32-bit integers in random generator */
+#define LUA_RAND32
+
+
+/* memory-allocator control variables */
+typedef struct Memcontrol {
+  unsigned long numblocks;
+  unsigned long total;
+  unsigned long maxmem;
+  unsigned long memlimit;
+  unsigned long countlimit;
+  unsigned long objcount[LUA_NUMTYPES];
+} Memcontrol;
+
+LUA_API Memcontrol l_memcontrol;
+
+
+/*
+** generic variable for debug tricks
+*/
+extern void *l_Trick;
+
+
+
+/*
+** Function to traverse and check all memory used by Lua
+*/
+int lua_checkmemory (lua_State *L);
+
+
+/* test for lock/unlock */
+
+struct L_EXTRA { int lock; int *plock; };
+#undef LUA_EXTRASPACE
+#define LUA_EXTRASPACE	sizeof(struct L_EXTRA)
+#define getlock(l)	cast(struct L_EXTRA*, lua_getextraspace(l))
+#define luai_userstateopen(l)  \
+	(getlock(l)->lock = 0, getlock(l)->plock = &(getlock(l)->lock))
+#define luai_userstateclose(l)  \
+  lua_assert(getlock(l)->lock == 1 && getlock(l)->plock == &(getlock(l)->lock))
+#define luai_userstatethread(l,l1) \
+  lua_assert(getlock(l1)->plock == getlock(l)->plock)
+#define luai_userstatefree(l,l1) \
+  lua_assert(getlock(l)->plock == getlock(l1)->plock)
+#define lua_lock(l)     lua_assert((*getlock(l)->plock)++ == 0)
+#define lua_unlock(l)   lua_assert(--(*getlock(l)->plock) == 0)
+
+
+
+LUA_API int luaB_opentests (lua_State *L);
+
+LUA_API void *debug_realloc (void *ud, void *block,
+                             size_t osize, size_t nsize);
+
+#if defined(lua_c)
+#define luaL_newstate()		lua_newstate(debug_realloc, &l_memcontrol)
+#define luaL_openlibs(L)  \
+  { (luaL_openlibs)(L); \
+     luaL_requiref(L, "T", luaB_opentests, 1); \
+     lua_pop(L, 1); }
+#endif
+
+
+
+/* change some sizes to give some bugs a chance */
+
+#undef LUAL_BUFFERSIZE
+#define LUAL_BUFFERSIZE		23
+#define MINSTRTABSIZE		2
+#define MAXIWTHABS		3
+
+#define STRCACHE_N	23
+#define STRCACHE_M	5
+
+#undef LUAI_USER_ALIGNMENT_T
+#define LUAI_USER_ALIGNMENT_T   union { char b[sizeof(void*) * 8]; }
+
+
+/* make stack-overflow tests run faster */
+#undef LUAI_MAXSTACK
+#define LUAI_MAXSTACK   50000
+
+
+/* force Lua to use its own implementations */
+#undef lua_strx2number
+#undef lua_number2strx
+
+
+#endif
+
diff --git a/test/external/lua-5.4.0-tests/main.lua b/test/external/lua-5.4.0-tests/main.lua
new file mode 100644
index 0000000..de14a08
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/main.lua
@@ -0,0 +1,468 @@
+# testing special comment on first line
+-- $Id: testes/main.lua $
+-- See Copyright Notice in file all.lua
+
+-- most (all?) tests here assume a reasonable "Unix-like" shell
+if _port then return end
+
+-- use only "double quotes" inside shell scripts (better change to
+-- run on Windows)
+
+
+print ("testing stand-alone interpreter")
+
+assert(os.execute())   -- machine has a system command
+
+local arg = arg or ARG
+
+local prog = os.tmpname()
+local otherprog = os.tmpname()
+local out = os.tmpname()
+
+local progname
+do
+  local i = 0
+  while arg[i] do i=i-1 end
+  progname = arg[i+1]
+end
+print("progname: "..progname)
+
+local prepfile = function (s, p)
+  p = p or prog
+  io.output(p)
+  io.write(s)
+  assert(io.close())
+end
+
+local function getoutput ()
+  io.input(out)
+  local t = io.read("a")
+  io.input():close()
+  assert(os.remove(out))
+  return t
+end
+
+local function checkprogout (s)
+  -- expected result must end with new line
+  assert(string.sub(s, -1) == "\n")
+  local t = getoutput()
+  for line in string.gmatch(s, ".-\n") do
+    assert(string.find(t, line, 1, true))
+  end
+end
+
+local function checkout (s)
+  local t = getoutput()
+  if s ~= t then print(string.format("'%s' - '%s'\n", s, t)) end
+  assert(s == t)
+  return t
+end
+
+
+local function RUN (p, ...)
+  p = string.gsub(p, "lua", '"'..progname..'"', 1)
+  local s = string.format(p, ...)
+  assert(os.execute(s))
+end
+
+local function NoRun (msg, p, ...)
+  p = string.gsub(p, "lua", '"'..progname..'"', 1)
+  local s = string.format(p, ...)
+  s = string.format("%s 2> %s", s, out)  -- will send error to 'out'
+  assert(not os.execute(s))
+  assert(string.find(getoutput(), msg, 1, true))  -- check error message
+end
+
+RUN('lua -v')
+
+print(string.format("(temporary program file used in these tests: %s)", prog))
+
+-- running stdin as a file
+prepfile""
+RUN('lua - < %s > %s', prog, out)
+checkout("")
+
+prepfile[[
+  print(
+1, a
+)
+]]
+RUN('lua - < %s > %s', prog, out)
+checkout("1\tnil\n")
+
+RUN('echo "print(10)\nprint(2)\n" | lua > %s', out)
+checkout("10\n2\n")
+
+
+-- test option '-'
+RUN('echo "print(arg[1])" | lua - -h > %s', out)
+checkout("-h\n")
+
+-- test environment variables used by Lua
+
+prepfile("print(package.path)")
+
+-- test LUA_PATH
+RUN('env LUA_INIT= LUA_PATH=x lua %s > %s', prog, out)
+checkout("x\n")
+
+-- test LUA_PATH_version
+RUN('env LUA_INIT= LUA_PATH_5_4=y LUA_PATH=x lua %s > %s', prog, out)
+checkout("y\n")
+
+-- test LUA_CPATH
+prepfile("print(package.cpath)")
+RUN('env LUA_INIT= LUA_CPATH=xuxu lua %s > %s', prog, out)
+checkout("xuxu\n")
+
+-- test LUA_CPATH_version
+RUN('env LUA_INIT= LUA_CPATH_5_4=yacc LUA_CPATH=x lua %s > %s', prog, out)
+checkout("yacc\n")
+
+-- test LUA_INIT (and its access to 'arg' table)
+prepfile("print(X)")
+RUN('env LUA_INIT="X=tonumber(arg[1])" lua %s 3.2 > %s', prog, out)
+checkout("3.2\n")
+
+-- test LUA_INIT_version
+prepfile("print(X)")
+RUN('env LUA_INIT_5_4="X=10" LUA_INIT="X=3" lua %s > %s', prog, out)
+checkout("10\n")
+
+-- test LUA_INIT for files
+prepfile("x = x or 10; print(x); x = x + 1")
+RUN('env LUA_INIT="@%s" lua %s > %s', prog, prog, out)
+checkout("10\n11\n")
+
+-- test errors in LUA_INIT
+NoRun('LUA_INIT:1: msg', 'env LUA_INIT="error(\'msg\')" lua')
+
+-- test option '-E'
+local defaultpath, defaultCpath
+
+do
+  prepfile("print(package.path, package.cpath)")
+  RUN('env LUA_INIT="error(10)" LUA_PATH=xxx LUA_CPATH=xxx lua -E %s > %s',
+       prog, out)
+  local output = getoutput()
+  defaultpath = string.match(output, "^(.-)\t")
+  defaultCpath = string.match(output, "\t(.-)$")
+
+  -- running with an empty environment
+  RUN('env -i lua %s > %s', prog, out)
+  local out = getoutput()
+  assert(defaultpath == string.match(output, "^(.-)\t"))
+  assert(defaultCpath == string.match(output, "\t(.-)$"))
+end
+
+-- paths did not change
+assert(not string.find(defaultpath, "xxx") and
+       string.find(defaultpath, "lua") and
+       not string.find(defaultCpath, "xxx") and
+       string.find(defaultCpath, "lua"))
+
+
+-- test replacement of ';;' to default path
+local function convert (p)
+  prepfile("print(package.path)")
+  RUN('env LUA_PATH="%s" lua %s > %s', p, prog, out)
+  local expected = getoutput()
+  expected = string.sub(expected, 1, -2)   -- cut final end of line
+  if string.find(p, ";;") then
+    p = string.gsub(p, ";;", ";"..defaultpath..";")
+    p = string.gsub(p, "^;", "")   -- remove ';' at the beginning
+    p = string.gsub(p, ";$", "")   -- remove ';' at the end
+  end
+  assert(p == expected)
+end
+
+convert(";")
+convert(";;")
+convert("a;;b")
+convert(";;b")
+convert("a;;")
+convert("a;b;;c")
+
+
+-- test -l over multiple libraries
+prepfile("print(1); a=2; return {x=15}")
+prepfile(("print(a); print(_G['%s'].x)"):format(prog), otherprog)
+RUN('env LUA_PATH="?;;" lua -l %s -l%s -lstring -l io %s > %s', prog, otherprog, otherprog, out)
+checkout("1\n2\n15\n2\n15\n")
+
+-- test 'arg' table
+local a = [[
+  assert(#arg == 3 and arg[1] == 'a' and
+         arg[2] == 'b' and arg[3] == 'c')
+  assert(arg[-1] == '--' and arg[-2] == "-e " and arg[-3] == '%s')
+  assert(arg[4] == undef and arg[-4] == undef)
+  local a, b, c = ...
+  assert(... == 'a' and a == 'a' and b == 'b' and c == 'c')
+]]
+a = string.format(a, progname)
+prepfile(a)
+RUN('lua "-e " -- %s a b c', prog)   -- "-e " runs an empty command
+
+-- test 'arg' availability in libraries
+prepfile"assert(arg)"
+prepfile("assert(arg)", otherprog)
+RUN('env LUA_PATH="?;;" lua -l%s - < %s', prog, otherprog)
+
+-- test messing up the 'arg' table
+RUN('echo "print(...)" | lua -e "arg[1] = 100" - > %s', out)
+checkout("100\n")
+NoRun("'arg' is not a table", 'echo "" | lua -e "arg = 1" -')
+
+-- test error in 'print'
+RUN('echo 10 | lua -e "print=nil" -i > /dev/null 2> %s', out)
+assert(string.find(getoutput(), "error calling 'print'"))
+
+-- test 'debug.debug'
+RUN('echo "io.stderr:write(1000)\ncont" | lua -e "require\'debug\'.debug()" 2> %s', out)
+checkout("lua_debug> 1000lua_debug> ")
+
+
+print("testing warnings")
+
+-- no warnings by default
+RUN('echo "io.stderr:write(1); warn[[XXX]]" | lua 2> %s', out)
+checkout("1")
+
+prepfile[[
+warn("@allow")               -- unknown control, ignored
+warn("@off", "XXX", "@off")  -- these are not control messages
+warn("@off")                 -- this one is
+warn("@on", "YYY", "@on")    -- not control, but warn is off
+warn("@off")                 -- keep it off
+warn("@on")                  -- restart warnings
+warn("", "@on")              -- again, no control, real warning
+warn("@on")                  -- keep it "started"
+warn("Z", "Z", "Z")          -- common warning
+]]
+RUN('lua -W %s 2> %s', prog, out)
+checkout[[
+Lua warning: @offXXX@off
+Lua warning: @on
+Lua warning: ZZZ
+]]
+
+prepfile[[
+warn("@allow")
+-- create two objects to be finalized when closing state
+-- the errors in the finalizers must generate warnings
+u1 = setmetatable({}, {__gc = function () error("XYZ") end})
+u2 = setmetatable({}, {__gc = function () error("ZYX") end})
+]]
+RUN('lua -W %s 2> %s', prog, out)
+checkprogout("ZYX)\nXYZ)\n")
+
+
+-- test many arguments
+prepfile[[print(({...})[30])]]
+RUN('lua %s %s > %s', prog, string.rep(" a", 30), out)
+checkout("a\n")
+
+RUN([[lua "-eprint(1)" -ea=3 -e "print(a)" > %s]], out)
+checkout("1\n3\n")
+
+-- test iteractive mode
+prepfile[[
+(6*2-6) -- ===
+a =
+10
+print(a)
+a]]
+RUN([[lua -e"_PROMPT='' _PROMPT2=''" -i < %s > %s]], prog, out)
+checkprogout("6\n10\n10\n\n")
+
+prepfile("a = [[b\nc\nd\ne]]\n=a")
+RUN([[lua -e"_PROMPT='' _PROMPT2=''" -i < %s > %s]], prog, out)
+checkprogout("b\nc\nd\ne\n\n")
+
+prompt = "alo"
+prepfile[[ --
+a = 2
+]]
+RUN([[lua "-e_PROMPT='%s'" -i < %s > %s]], prompt, prog, out)
+local t = getoutput()
+assert(string.find(t, prompt .. ".*" .. prompt .. ".*" .. prompt))
+
+-- test for error objects
+prepfile[[
+debug = require "debug"
+m = {x=0}
+setmetatable(m, {__tostring = function(x)
+  return tostring(debug.getinfo(4).currentline + x.x)
+end})
+error(m)
+]]
+NoRun(progname .. ": 6\n", [[lua %s]], prog)
+
+prepfile("error{}")
+NoRun("error object is a table value", [[lua %s]], prog)
+
+
+-- chunk broken in many lines
+s = [=[ --
+function f ( x )
+  local a = [[
+xuxu
+]]
+  local b = "\
+xuxu\n"
+  if x == 11 then return 1 + 12 , 2 + 20 end  --[[ test multiple returns ]]
+  return x + 1
+  --\\
+end
+return( f( 100 ) )
+assert( a == b )
+do return f( 11 ) end  ]=]
+s = string.gsub(s, ' ', '\n\n')   -- change all spaces for newlines
+prepfile(s)
+RUN([[lua -e"_PROMPT='' _PROMPT2=''" -i < %s > %s]], prog, out)
+checkprogout("101\n13\t22\n\n")
+
+prepfile[[#comment in 1st line without \n at the end]]
+RUN('lua %s', prog)
+
+prepfile[[#test line number when file starts with comment line
+debug = require"debug"
+print(debug.getinfo(1).currentline)
+]]
+RUN('lua %s > %s', prog, out)
+checkprogout('3\n')
+
+-- close Lua with an open file
+prepfile(string.format([[io.output(%q); io.write('alo')]], out))
+RUN('lua %s', prog)
+checkout('alo')
+
+-- bug in 5.2 beta (extra \0 after version line)
+RUN([[lua -v  -e"print'hello'" > %s]], out)
+t = getoutput()
+assert(string.find(t, "PUC%-Rio\nhello"))
+
+
+-- testing os.exit
+prepfile("os.exit(nil, true)")
+RUN('lua %s', prog)
+prepfile("os.exit(0, true)")
+RUN('lua %s', prog)
+prepfile("os.exit(true, true)")
+RUN('lua %s', prog)
+prepfile("os.exit(1, true)")
+NoRun("", "lua %s", prog)   -- no message
+prepfile("os.exit(false, true)")
+NoRun("", "lua %s", prog)   -- no message
+
+
+-- to-be-closed variables in main chunk
+prepfile[[
+  local x <close> = setmetatable({},
+        {__close = function (self, err)
+                     assert(err == nil)
+                     print("Ok")
+                   end})
+  local e1 <close> = setmetatable({}, {__close = function () print(120) end})
+  os.exit(true, true)
+]]
+RUN('lua %s > %s', prog, out)
+checkprogout("120\nOk\n")
+
+
+-- remove temporary files
+assert(os.remove(prog))
+assert(os.remove(otherprog))
+assert(not os.remove(out))
+
+-- invalid options
+NoRun("unrecognized option '-h'", "lua -h")
+NoRun("unrecognized option '---'", "lua ---")
+NoRun("unrecognized option '-Ex'", "lua -Ex")
+NoRun("unrecognized option '-vv'", "lua -vv")
+NoRun("unrecognized option '-iv'", "lua -iv")
+NoRun("'-e' needs argument", "lua -e")
+NoRun("syntax error", "lua -e a")
+NoRun("'-l' needs argument", "lua -l")
+
+
+if T then   -- test library?
+  print("testing 'not enough memory' to create a state")
+  NoRun("not enough memory", "env MEMLIMIT=100 lua")
+
+  -- testing 'warn'
+  warn("@store")
+  warn("@123", "456", "789")
+  assert(_WARN == "@123456789"); _WARN = nil
+
+  warn("zip", "", " ", "zap")
+  assert(_WARN == "zip zap"); _WARN = nil
+  warn("ZIP", "", " ", "ZAP")
+  assert(_WARN == "ZIP ZAP"); _WARN = nil
+  warn("@normal")
+end
+
+do
+  -- 'warn' must get at least one argument
+  local st, msg = pcall(warn)
+  assert(string.find(msg, "string expected"))
+
+  -- 'warn' does not leave unfinished warning in case of errors
+  -- (message would appear in next warning)
+  st, msg = pcall(warn, "SHOULD NOT APPEAR", {})
+  assert(string.find(msg, "string expected"))
+end
+
+print('+')
+
+print('testing Ctrl C')
+do
+  -- interrupt a script
+  local function kill (pid)
+    return os.execute(string.format('kill -INT %s 2> /dev/null', pid))
+  end
+
+  -- function to run a script in background, returning its output file
+  -- descriptor and its pid
+  local function runback (luaprg)
+    -- shell script to run 'luaprg' in background and echo its pid
+    local shellprg = string.format('%s -e "%s" & echo $!', progname, luaprg)
+    local f = io.popen(shellprg, "r")   -- run shell script
+    local pid = f:read()   -- get pid for Lua script
+    print("(if test fails now, it may leave a Lua script running in \z
+            background, pid " .. pid .. ")")
+    return f, pid
+  end
+
+  -- Lua script that runs protected infinite loop and then prints '42'
+  local f, pid = runback[[
+    pcall(function () print(12); while true do end end); print(42)]]
+  -- wait until script is inside 'pcall'
+  assert(f:read() == "12")
+  kill(pid)  -- send INT signal to Lua script
+  -- check that 'pcall' captured the exception and script continued running
+  assert(f:read() == "42")  -- expected output
+  assert(f:close())
+  print("done")
+
+  -- Lua script in a long unbreakable search
+  local f, pid = runback[[
+    print(15); string.find(string.rep('a', 100000), '.*b')]]
+  -- wait (so script can reach the loop)
+  assert(f:read() == "15")
+  assert(os.execute("sleep 1"))
+  -- must send at least two INT signals to stop this Lua script
+  local n = 100
+  for i = 0, 100 do   -- keep sending signals
+    if not kill(pid) then   -- until it fails
+      n = i   -- number of non-failed kills
+      break
+    end
+  end
+  assert(f:close())
+  assert(n >= 2)
+  print(string.format("done (with %d kills)", n))
+
+end
+
+print("OK")
diff --git a/test/external/lua-5.4.0-tests/math.lua b/test/external/lua-5.4.0-tests/math.lua
new file mode 100644
index 0000000..930221e
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/math.lua
@@ -0,0 +1,1023 @@
+-- $Id: testes/math.lua $
+-- See Copyright Notice in file all.lua
+
+print("testing numbers and math lib")
+
+local minint <const> = math.mininteger
+local maxint <const> = math.maxinteger
+
+local intbits <const> = math.floor(math.log(maxint, 2) + 0.5) + 1
+assert((1 << intbits) == 0)
+
+assert(minint == 1 << (intbits - 1))
+assert(maxint == minint - 1)
+
+-- number of bits in the mantissa of a floating-point number
+local floatbits = 24
+do
+  local p = 2.0^floatbits
+  while p < p + 1.0 do
+    p = p * 2.0
+    floatbits = floatbits + 1
+  end
+end
+
+local function isNaN (x)
+  return (x ~= x)
+end
+
+assert(isNaN(0/0))
+assert(not isNaN(1/0))
+
+
+do
+  local x = 2.0^floatbits
+  assert(x > x - 1.0 and x == x + 1.0)
+
+  print(string.format("%d-bit integers, %d-bit (mantissa) floats",
+                       intbits, floatbits))
+end
+
+assert(math.type(0) == "integer" and math.type(0.0) == "float"
+       and not math.type("10"))
+
+
+local function checkerror (msg, f, ...)
+  local s, err = pcall(f, ...)
+  assert(not s and string.find(err, msg))
+end
+
+local msgf2i = "number.* has no integer representation"
+
+-- float equality
+function eq (a,b,limit)
+  if not limit then
+    if floatbits >= 50 then limit = 1E-11
+    else limit = 1E-5
+    end
+  end
+  -- a == b needed for +inf/-inf
+  return a == b or math.abs(a-b) <= limit
+end
+
+
+-- equality with types
+function eqT (a,b)
+  return a == b and math.type(a) == math.type(b)
+end
+
+
+-- basic float notation
+assert(0e12 == 0 and .0 == 0 and 0. == 0 and .2e2 == 20 and 2.E-1 == 0.2)
+
+do
+  local a,b,c = "2", " 3e0 ", " 10  "
+  assert(a+b == 5 and -b == -3 and b+"2" == 5 and "10"-c == 0)
+  assert(type(a) == 'string' and type(b) == 'string' and type(c) == 'string')
+  assert(a == "2" and b == " 3e0 " and c == " 10  " and -c == -"  10 ")
+  assert(c%a == 0 and a^b == 08)
+  a = 0
+  assert(a == -a and 0 == -0)
+end
+
+do
+  local x = -1
+  local mz = 0/x   -- minus zero
+  t = {[0] = 10, 20, 30, 40, 50}
+  assert(t[mz] == t[0] and t[-0] == t[0])
+end
+
+do   -- tests for 'modf'
+  local a,b = math.modf(3.5)
+  assert(a == 3.0 and b == 0.5)
+  a,b = math.modf(-2.5)
+  assert(a == -2.0 and b == -0.5)
+  a,b = math.modf(-3e23)
+  assert(a == -3e23 and b == 0.0)
+  a,b = math.modf(3e35)
+  assert(a == 3e35 and b == 0.0)
+  a,b = math.modf(-1/0)   -- -inf
+  assert(a == -1/0 and b == 0.0)
+  a,b = math.modf(1/0)   -- inf
+  assert(a == 1/0 and b == 0.0)
+  a,b = math.modf(0/0)   -- NaN
+  assert(isNaN(a) and isNaN(b))
+  a,b = math.modf(3)  -- integer argument
+  assert(eqT(a, 3) and eqT(b, 0.0))
+  a,b = math.modf(minint)
+  assert(eqT(a, minint) and eqT(b, 0.0))
+end
+
+assert(math.huge > 10e30)
+assert(-math.huge < -10e30)
+
+
+-- integer arithmetic
+assert(minint < minint + 1)
+assert(maxint - 1 < maxint)
+assert(0 - minint == minint)
+assert(minint * minint == 0)
+assert(maxint * maxint * maxint == maxint)
+
+
+-- testing floor division and conversions
+
+for _, i in pairs{-16, -15, -3, -2, -1, 0, 1, 2, 3, 15} do
+  for _, j in pairs{-16, -15, -3, -2, -1, 1, 2, 3, 15} do
+    for _, ti in pairs{0, 0.0} do     -- try 'i' as integer and as float
+      for _, tj in pairs{0, 0.0} do   -- try 'j' as integer and as float
+        local x = i + ti
+        local y = j + tj
+          assert(i//j == math.floor(i/j))
+      end
+    end
+  end
+end
+
+assert(1//0.0 == 1/0)
+assert(-1 // 0.0 == -1/0)
+assert(eqT(3.5 // 1.5, 2.0))
+assert(eqT(3.5 // -1.5, -3.0))
+
+do   -- tests for different kinds of opcodes
+  local x, y 
+  x = 1; assert(x // 0.0 == 1/0)
+  x = 1.0; assert(x // 0 == 1/0)
+  x = 3.5; assert(eqT(x // 1, 3.0))
+  assert(eqT(x // -1, -4.0))
+
+  x = 3.5; y = 1.5; assert(eqT(x // y, 2.0))
+  x = 3.5; y = -1.5; assert(eqT(x // y, -3.0))
+end
+
+assert(maxint // maxint == 1)
+assert(maxint // 1 == maxint)
+assert((maxint - 1) // maxint == 0)
+assert(maxint // (maxint - 1) == 1)
+assert(minint // minint == 1)
+assert(minint // minint == 1)
+assert((minint + 1) // minint == 0)
+assert(minint // (minint + 1) == 1)
+assert(minint // 1 == minint)
+
+assert(minint // -1 == -minint)
+assert(minint // -2 == 2^(intbits - 2))
+assert(maxint // -1 == -maxint)
+
+
+-- negative exponents
+do
+  assert(2^-3 == 1 / 2^3)
+  assert(eq((-3)^-3, 1 / (-3)^3))
+  for i = -3, 3 do    -- variables avoid constant folding
+      for j = -3, 3 do
+        -- domain errors (0^(-n)) are not portable
+        if not _port or i ~= 0 or j > 0 then
+          assert(eq(i^j, 1 / i^(-j)))
+       end
+    end
+  end
+end
+
+-- comparison between floats and integers (border cases)
+if floatbits < intbits then
+  assert(2.0^floatbits == (1 << floatbits))
+  assert(2.0^floatbits - 1.0 == (1 << floatbits) - 1.0)
+  assert(2.0^floatbits - 1.0 ~= (1 << floatbits))
+  -- float is rounded, int is not
+  assert(2.0^floatbits + 1.0 ~= (1 << floatbits) + 1)
+else   -- floats can express all integers with full accuracy
+  assert(maxint == maxint + 0.0)
+  assert(maxint - 1 == maxint - 1.0)
+  assert(minint + 1 == minint + 1.0)
+  assert(maxint ~= maxint - 1.0)
+end
+assert(maxint + 0.0 == 2.0^(intbits - 1) - 1.0)
+assert(minint + 0.0 == minint)
+assert(minint + 0.0 == -2.0^(intbits - 1))
+
+
+-- order between floats and integers
+assert(1 < 1.1); assert(not (1 < 0.9))
+assert(1 <= 1.1); assert(not (1 <= 0.9))
+assert(-1 < -0.9); assert(not (-1 < -1.1))
+assert(1 <= 1.1); assert(not (-1 <= -1.1))
+assert(-1 < -0.9); assert(not (-1 < -1.1))
+assert(-1 <= -0.9); assert(not (-1 <= -1.1))
+assert(minint <= minint + 0.0)
+assert(minint + 0.0 <= minint)
+assert(not (minint < minint + 0.0))
+assert(not (minint + 0.0 < minint))
+assert(maxint < minint * -1.0)
+assert(maxint <= minint * -1.0)
+
+do
+  local fmaxi1 = 2^(intbits - 1)
+  assert(maxint < fmaxi1)
+  assert(maxint <= fmaxi1)
+  assert(not (fmaxi1 <= maxint))
+  assert(minint <= -2^(intbits - 1))
+  assert(-2^(intbits - 1) <= minint)
+end
+
+if floatbits < intbits then
+  print("testing order (floats cannot represent all integers)")
+  local fmax = 2^floatbits
+  local ifmax = fmax | 0
+  assert(fmax < ifmax + 1)
+  assert(fmax - 1 < ifmax)
+  assert(-(fmax - 1) > -ifmax)
+  assert(not (fmax <= ifmax - 1))
+  assert(-fmax > -(ifmax + 1))
+  assert(not (-fmax >= -(ifmax - 1)))
+
+  assert(fmax/2 - 0.5 < ifmax//2)
+  assert(-(fmax/2 - 0.5) > -ifmax//2)
+
+  assert(maxint < 2^intbits)
+  assert(minint > -2^intbits)
+  assert(maxint <= 2^intbits)
+  assert(minint >= -2^intbits)
+else
+  print("testing order (floats can represent all integers)")
+  assert(maxint < maxint + 1.0)
+  assert(maxint < maxint + 0.5)
+  assert(maxint - 1.0 < maxint)
+  assert(maxint - 0.5 < maxint)
+  assert(not (maxint + 0.0 < maxint))
+  assert(maxint + 0.0 <= maxint)
+  assert(not (maxint < maxint + 0.0))
+  assert(maxint + 0.0 <= maxint)
+  assert(maxint <= maxint + 0.0)
+  assert(not (maxint + 1.0 <= maxint))
+  assert(not (maxint + 0.5 <= maxint))
+  assert(not (maxint <= maxint - 1.0))
+  assert(not (maxint <= maxint - 0.5))
+
+  assert(minint < minint + 1.0)
+  assert(minint < minint + 0.5)
+  assert(minint <= minint + 0.5)
+  assert(minint - 1.0 < minint)
+  assert(minint - 1.0 <= minint)
+  assert(not (minint + 0.0 < minint))
+  assert(not (minint + 0.5 < minint))
+  assert(not (minint < minint + 0.0))
+  assert(minint + 0.0 <= minint)
+  assert(minint <= minint + 0.0)
+  assert(not (minint + 1.0 <= minint))
+  assert(not (minint + 0.5 <= minint))
+  assert(not (minint <= minint - 1.0))
+end
+
+do
+  local NaN <const> = 0/0
+  assert(not (NaN < 0))
+  assert(not (NaN > minint))
+  assert(not (NaN <= -9))
+  assert(not (NaN <= maxint))
+  assert(not (NaN < maxint))
+  assert(not (minint <= NaN))
+  assert(not (minint < NaN))
+  assert(not (4 <= NaN))
+  assert(not (4 < NaN))
+end
+
+
+-- avoiding errors at compile time
+local function checkcompt (msg, code)
+  checkerror(msg, assert(load(code)))
+end
+checkcompt("divide by zero", "return 2 // 0")
+checkcompt(msgf2i, "return 2.3 >> 0")
+checkcompt(msgf2i, ("return 2.0^%d & 1"):format(intbits - 1))
+checkcompt("field 'huge'", "return math.huge << 1")
+checkcompt(msgf2i, ("return 1 | 2.0^%d"):format(intbits - 1))
+checkcompt(msgf2i, "return 2.3 ~ 0.0")
+
+
+-- testing overflow errors when converting from float to integer (runtime)
+local function f2i (x) return x | x end
+checkerror(msgf2i, f2i, math.huge)     -- +inf
+checkerror(msgf2i, f2i, -math.huge)    -- -inf
+checkerror(msgf2i, f2i, 0/0)           -- NaN
+
+if floatbits < intbits then
+  -- conversion tests when float cannot represent all integers
+  assert(maxint + 1.0 == maxint + 0.0)
+  assert(minint - 1.0 == minint + 0.0)
+  checkerror(msgf2i, f2i, maxint + 0.0)
+  assert(f2i(2.0^(intbits - 2)) == 1 << (intbits - 2))
+  assert(f2i(-2.0^(intbits - 2)) == -(1 << (intbits - 2)))
+  assert((2.0^(floatbits - 1) + 1.0) // 1 == (1 << (floatbits - 1)) + 1)
+  -- maximum integer representable as a float
+  local mf = maxint - (1 << (floatbits - intbits)) + 1
+  assert(f2i(mf + 0.0) == mf)  -- OK up to here
+  mf = mf + 1
+  assert(f2i(mf + 0.0) ~= mf)   -- no more representable
+else
+  -- conversion tests when float can represent all integers
+  assert(maxint + 1.0 > maxint)
+  assert(minint - 1.0 < minint)
+  assert(f2i(maxint + 0.0) == maxint)
+  checkerror("no integer rep", f2i, maxint + 1.0)
+  checkerror("no integer rep", f2i, minint - 1.0)
+end
+
+-- 'minint' should be representable as a float no matter the precision
+assert(f2i(minint + 0.0) == minint)
+
+
+-- testing numeric strings
+
+assert("2" + 1 == 3)
+assert("2 " + 1 == 3)
+assert(" -2 " + 1 == -1)
+assert(" -0xa " + 1 == -9)
+
+
+-- Literal integer Overflows (new behavior in 5.3.3)
+do
+  -- no overflows
+  assert(eqT(tonumber(tostring(maxint)), maxint))
+  assert(eqT(tonumber(tostring(minint)), minint))
+
+  -- add 1 to last digit as a string (it cannot be 9...)
+  local function incd (n)
+    local s = string.format("%d", n)
+    s = string.gsub(s, "%d$", function (d)
+          assert(d ~= '9')
+          return string.char(string.byte(d) + 1)
+        end)
+    return s
+  end
+
+  -- 'tonumber' with overflow by 1
+  assert(eqT(tonumber(incd(maxint)), maxint + 1.0))
+  assert(eqT(tonumber(incd(minint)), minint - 1.0))
+
+  -- large numbers
+  assert(eqT(tonumber("1"..string.rep("0", 30)), 1e30))
+  assert(eqT(tonumber("-1"..string.rep("0", 30)), -1e30))
+
+  -- hexa format still wraps around
+  assert(eqT(tonumber("0x1"..string.rep("0", 30)), 0))
+
+  -- lexer in the limits
+  assert(minint == load("return " .. minint)())
+  assert(eqT(maxint, load("return " .. maxint)()))
+
+  assert(eqT(10000000000000000000000.0, 10000000000000000000000))
+  assert(eqT(-10000000000000000000000.0, -10000000000000000000000))
+end
+
+
+-- testing 'tonumber'
+
+-- 'tonumber' with numbers
+assert(tonumber(3.4) == 3.4)
+assert(eqT(tonumber(3), 3))
+assert(eqT(tonumber(maxint), maxint) and eqT(tonumber(minint), minint))
+assert(tonumber(1/0) == 1/0)
+
+-- 'tonumber' with strings
+assert(tonumber("0") == 0)
+assert(not tonumber(""))
+assert(not tonumber("  "))
+assert(not tonumber("-"))
+assert(not tonumber("  -0x "))
+assert(not tonumber{})
+assert(tonumber'+0.01' == 1/100 and tonumber'+.01' == 0.01 and
+       tonumber'.01' == 0.01    and tonumber'-1.' == -1 and
+       tonumber'+1.' == 1)
+assert(not tonumber'+ 0.01' and not tonumber'+.e1' and
+       not tonumber'1e'     and not tonumber'1.0e+' and
+       not tonumber'.')
+assert(tonumber('-012') == -010-2)
+assert(tonumber('-1.2e2') == - - -120)
+
+assert(tonumber("0xffffffffffff") == (1 << (4*12)) - 1)
+assert(tonumber("0x"..string.rep("f", (intbits//4))) == -1)
+assert(tonumber("-0x"..string.rep("f", (intbits//4))) == 1)
+
+-- testing 'tonumber' with base
+assert(tonumber('  001010  ', 2) == 10)
+assert(tonumber('  001010  ', 10) == 001010)
+assert(tonumber('  -1010  ', 2) == -10)
+assert(tonumber('10', 36) == 36)
+assert(tonumber('  -10  ', 36) == -36)
+assert(tonumber('  +1Z  ', 36) == 36 + 35)
+assert(tonumber('  -1z  ', 36) == -36 + -35)
+assert(tonumber('-fFfa', 16) == -(10+(16*(15+(16*(15+(16*15)))))))
+assert(tonumber(string.rep('1', (intbits - 2)), 2) + 1 == 2^(intbits - 2))
+assert(tonumber('ffffFFFF', 16)+1 == (1 << 32))
+assert(tonumber('0ffffFFFF', 16)+1 == (1 << 32))
+assert(tonumber('-0ffffffFFFF', 16) - 1 == -(1 << 40))
+for i = 2,36 do
+  local i2 = i * i
+  local i10 = i2 * i2 * i2 * i2 * i2      -- i^10
+  assert(tonumber('\t10000000000\t', i) == i10)
+end
+
+if not _soft then
+  -- tests with very long numerals
+  assert(tonumber("0x"..string.rep("f", 13)..".0") == 2.0^(4*13) - 1)
+  assert(tonumber("0x"..string.rep("f", 150)..".0") == 2.0^(4*150) - 1)
+  assert(tonumber("0x"..string.rep("f", 300)..".0") == 2.0^(4*300) - 1)
+  assert(tonumber("0x"..string.rep("f", 500)..".0") == 2.0^(4*500) - 1)
+  assert(tonumber('0x3.' .. string.rep('0', 1000)) == 3)
+  assert(tonumber('0x' .. string.rep('0', 1000) .. 'a') == 10)
+  assert(tonumber('0x0.' .. string.rep('0', 13).."1") == 2.0^(-4*14))
+  assert(tonumber('0x0.' .. string.rep('0', 150).."1") == 2.0^(-4*151))
+  assert(tonumber('0x0.' .. string.rep('0', 300).."1") == 2.0^(-4*301))
+  assert(tonumber('0x0.' .. string.rep('0', 500).."1") == 2.0^(-4*501))
+
+  assert(tonumber('0xe03' .. string.rep('0', 1000) .. 'p-4000') == 3587.0)
+  assert(tonumber('0x.' .. string.rep('0', 1000) .. '74p4004') == 0x7.4)
+end
+
+-- testing 'tonumber' for invalid formats
+
+local function f (...)
+  if select('#', ...) == 1 then
+    return (...)
+  else
+    return "***"
+  end
+end
+
+assert(not f(tonumber('fFfa', 15)))
+assert(not f(tonumber('099', 8)))
+assert(not f(tonumber('1\0', 2)))
+assert(not f(tonumber('', 8)))
+assert(not f(tonumber('  ', 9)))
+assert(not f(tonumber('  ', 9)))
+assert(not f(tonumber('0xf', 10)))
+
+assert(not f(tonumber('inf')))
+assert(not f(tonumber(' INF ')))
+assert(not f(tonumber('Nan')))
+assert(not f(tonumber('nan')))
+
+assert(not f(tonumber('  ')))
+assert(not f(tonumber('')))
+assert(not f(tonumber('1  a')))
+assert(not f(tonumber('1  a', 2)))
+assert(not f(tonumber('1\0')))
+assert(not f(tonumber('1 \0')))
+assert(not f(tonumber('1\0 ')))
+assert(not f(tonumber('e1')))
+assert(not f(tonumber('e  1')))
+assert(not f(tonumber(' 3.4.5 ')))
+
+
+-- testing 'tonumber' for invalid hexadecimal formats
+
+assert(not tonumber('0x'))
+assert(not tonumber('x'))
+assert(not tonumber('x3'))
+assert(not tonumber('0x3.3.3'))   -- two decimal points
+assert(not tonumber('00x2'))
+assert(not tonumber('0x 2'))
+assert(not tonumber('0 x2'))
+assert(not tonumber('23x'))
+assert(not tonumber('- 0xaa'))
+assert(not tonumber('-0xaaP '))   -- no exponent
+assert(not tonumber('0x0.51p'))
+assert(not tonumber('0x5p+-2'))
+
+
+-- testing hexadecimal numerals
+
+assert(0x10 == 16 and 0xfff == 2^12 - 1 and 0XFB == 251)
+assert(0x0p12 == 0 and 0x.0p-3 == 0)
+assert(0xFFFFFFFF == (1 << 32) - 1)
+assert(tonumber('+0x2') == 2)
+assert(tonumber('-0xaA') == -170)
+assert(tonumber('-0xffFFFfff') == -(1 << 32) + 1)
+
+-- possible confusion with decimal exponent
+assert(0E+1 == 0 and 0xE+1 == 15 and 0xe-1 == 13)
+
+
+-- floating hexas
+
+assert(tonumber('  0x2.5  ') == 0x25/16)
+assert(tonumber('  -0x2.5  ') == -0x25/16)
+assert(tonumber('  +0x0.51p+8  ') == 0x51)
+assert(0x.FfffFFFF == 1 - '0x.00000001')
+assert('0xA.a' + 0 == 10 + 10/16)
+assert(0xa.aP4 == 0XAA)
+assert(0x4P-2 == 1)
+assert(0x1.1 == '0x1.' + '+0x.1')
+assert(0Xabcdef.0 == 0x.ABCDEFp+24)
+
+
+assert(1.1 == 1.+.1)
+assert(100.0 == 1E2 and .01 == 1e-2)
+assert(1111111111 - 1111111110 == 1000.00e-03)
+assert(1.1 == '1.'+'.1')
+assert(tonumber'1111111111' - tonumber'1111111110' ==
+       tonumber"  +0.001e+3 \n\t")
+
+assert(0.1e-30 > 0.9E-31 and 0.9E30 < 0.1e31)
+
+assert(0.123456 > 0.123455)
+
+assert(tonumber('+1.23E18') == 1.23*10.0^18)
+
+-- testing order operators
+assert(not(1<1) and (1<2) and not(2<1))
+assert(not('a'<'a') and ('a'<'b') and not('b'<'a'))
+assert((1<=1) and (1<=2) and not(2<=1))
+assert(('a'<='a') and ('a'<='b') and not('b'<='a'))
+assert(not(1>1) and not(1>2) and (2>1))
+assert(not('a'>'a') and not('a'>'b') and ('b'>'a'))
+assert((1>=1) and not(1>=2) and (2>=1))
+assert(('a'>='a') and not('a'>='b') and ('b'>='a'))
+assert(1.3 < 1.4 and 1.3 <= 1.4 and not (1.3 < 1.3) and 1.3 <= 1.3)
+
+-- testing mod operator
+assert(eqT(-4 % 3, 2))
+assert(eqT(4 % -3, -2))
+assert(eqT(-4.0 % 3, 2.0))
+assert(eqT(4 % -3.0, -2.0))
+assert(eqT(4 % -5, -1))
+assert(eqT(4 % -5.0, -1.0))
+assert(eqT(4 % 5, 4))
+assert(eqT(4 % 5.0, 4.0))
+assert(eqT(-4 % -5, -4))
+assert(eqT(-4 % -5.0, -4.0))
+assert(eqT(-4 % 5, 1))
+assert(eqT(-4 % 5.0, 1.0))
+assert(eqT(4.25 % 4, 0.25))
+assert(eqT(10.0 % 2, 0.0))
+assert(eqT(-10.0 % 2, 0.0))
+assert(eqT(-10.0 % -2, 0.0))
+assert(math.pi - math.pi % 1 == 3)
+assert(math.pi - math.pi % 0.001 == 3.141)
+
+do   -- very small numbers
+  local i, j = 0, 20000
+  while i < j do
+    local m = (i + j) // 2
+    if 10^-m > 0 then
+      i = m + 1
+    else
+      j = m
+    end
+  end
+  -- 'i' is the smallest possible ten-exponent
+  local b = 10^-(i - (i // 10))   -- a very small number
+  assert(b > 0 and b * b == 0)
+  local delta = b / 1000
+  assert(eq((2.1 * b) % (2 * b), (0.1 * b), delta))
+  assert(eq((-2.1 * b) % (2 * b), (2 * b) - (0.1 * b), delta))
+  assert(eq((2.1 * b) % (-2 * b), (0.1 * b) - (2 * b), delta))
+  assert(eq((-2.1 * b) % (-2 * b), (-0.1 * b), delta))
+end
+
+
+-- basic consistency between integer modulo and float modulo
+for i = -10, 10 do
+  for j = -10, 10 do
+    if j ~= 0 then
+      assert((i + 0.0) % j == i % j)
+    end
+  end
+end
+
+for i = 0, 10 do
+  for j = -10, 10 do
+    if j ~= 0 then
+      assert((2^i) % j == (1 << i) % j)
+    end
+  end
+end
+
+do    -- precision of module for large numbers
+  local i = 10
+  while (1 << i) > 0 do
+    assert((1 << i) % 3 == i % 2 + 1)
+    i = i + 1
+  end
+
+  i = 10
+  while 2^i < math.huge do
+    assert(2^i % 3 == i % 2 + 1)
+    i = i + 1
+  end
+end
+
+assert(eqT(minint % minint, 0))
+assert(eqT(maxint % maxint, 0))
+assert((minint + 1) % minint == minint + 1)
+assert((maxint - 1) % maxint == maxint - 1)
+assert(minint % maxint == maxint - 1)
+
+assert(minint % -1 == 0)
+assert(minint % -2 == 0)
+assert(maxint % -2 == -1)
+
+-- non-portable tests because Windows C library cannot compute 
+-- fmod(1, huge) correctly
+if not _port then
+  local function anan (x) assert(isNaN(x)) end   -- assert Not a Number
+  anan(0.0 % 0)
+  anan(1.3 % 0)
+  anan(math.huge % 1)
+  anan(math.huge % 1e30)
+  anan(-math.huge % 1e30)
+  anan(-math.huge % -1e30)
+  assert(1 % math.huge == 1)
+  assert(1e30 % math.huge == 1e30)
+  assert(1e30 % -math.huge == -math.huge)
+  assert(-1 % math.huge == math.huge)
+  assert(-1 % -math.huge == -1)
+end
+
+
+-- testing unsigned comparisons
+assert(math.ult(3, 4))
+assert(not math.ult(4, 4))
+assert(math.ult(-2, -1))
+assert(math.ult(2, -1))
+assert(not math.ult(-2, -2))
+assert(math.ult(maxint, minint))
+assert(not math.ult(minint, maxint))
+
+
+assert(eq(math.sin(-9.8)^2 + math.cos(-9.8)^2, 1))
+assert(eq(math.tan(math.pi/4), 1))
+assert(eq(math.sin(math.pi/2), 1) and eq(math.cos(math.pi/2), 0))
+assert(eq(math.atan(1), math.pi/4) and eq(math.acos(0), math.pi/2) and
+       eq(math.asin(1), math.pi/2))
+assert(eq(math.deg(math.pi/2), 90) and eq(math.rad(90), math.pi/2))
+assert(math.abs(-10.43) == 10.43)
+assert(eqT(math.abs(minint), minint))
+assert(eqT(math.abs(maxint), maxint))
+assert(eqT(math.abs(-maxint), maxint))
+assert(eq(math.atan(1,0), math.pi/2))
+assert(math.fmod(10,3) == 1)
+assert(eq(math.sqrt(10)^2, 10))
+assert(eq(math.log(2, 10), math.log(2)/math.log(10)))
+assert(eq(math.log(2, 2), 1))
+assert(eq(math.log(9, 3), 2))
+assert(eq(math.exp(0), 1))
+assert(eq(math.sin(10), math.sin(10%(2*math.pi))))
+
+
+assert(tonumber(' 1.3e-2 ') == 1.3e-2)
+assert(tonumber(' -1.00000000000001 ') == -1.00000000000001)
+
+-- testing constant limits
+-- 2^23 = 8388608
+assert(8388609 + -8388609 == 0)
+assert(8388608 + -8388608 == 0)
+assert(8388607 + -8388607 == 0)
+
+
+
+do   -- testing floor & ceil
+  assert(eqT(math.floor(3.4), 3))
+  assert(eqT(math.ceil(3.4), 4))
+  assert(eqT(math.floor(-3.4), -4))
+  assert(eqT(math.ceil(-3.4), -3))
+  assert(eqT(math.floor(maxint), maxint))
+  assert(eqT(math.ceil(maxint), maxint))
+  assert(eqT(math.floor(minint), minint))
+  assert(eqT(math.floor(minint + 0.0), minint))
+  assert(eqT(math.ceil(minint), minint))
+  assert(eqT(math.ceil(minint + 0.0), minint))
+  assert(math.floor(1e50) == 1e50)
+  assert(math.ceil(1e50) == 1e50)
+  assert(math.floor(-1e50) == -1e50)
+  assert(math.ceil(-1e50) == -1e50)
+  for _, p in pairs{31,32,63,64} do
+    assert(math.floor(2^p) == 2^p)
+    assert(math.floor(2^p + 0.5) == 2^p)
+    assert(math.ceil(2^p) == 2^p)
+    assert(math.ceil(2^p - 0.5) == 2^p)
+  end
+  checkerror("number expected", math.floor, {})
+  checkerror("number expected", math.ceil, print)
+  assert(eqT(math.tointeger(minint), minint))
+  assert(eqT(math.tointeger(minint .. ""), minint))
+  assert(eqT(math.tointeger(maxint), maxint))
+  assert(eqT(math.tointeger(maxint .. ""), maxint))
+  assert(eqT(math.tointeger(minint + 0.0), minint))
+  assert(not math.tointeger(0.0 - minint))
+  assert(not math.tointeger(math.pi))
+  assert(not math.tointeger(-math.pi))
+  assert(math.floor(math.huge) == math.huge)
+  assert(math.ceil(math.huge) == math.huge)
+  assert(not math.tointeger(math.huge))
+  assert(math.floor(-math.huge) == -math.huge)
+  assert(math.ceil(-math.huge) == -math.huge)
+  assert(not math.tointeger(-math.huge))
+  assert(math.tointeger("34.0") == 34)
+  assert(not math.tointeger("34.3"))
+  assert(not math.tointeger({}))
+  assert(not math.tointeger(0/0))    -- NaN
+end
+
+
+-- testing fmod for integers
+for i = -6, 6 do
+  for j = -6, 6 do
+    if j ~= 0 then
+      local mi = math.fmod(i, j)
+      local mf = math.fmod(i + 0.0, j)
+      assert(mi == mf)
+      assert(math.type(mi) == 'integer' and math.type(mf) == 'float')
+      if (i >= 0 and j >= 0) or (i <= 0 and j <= 0) or mi == 0 then
+        assert(eqT(mi, i % j))
+      end
+    end
+  end
+end
+assert(eqT(math.fmod(minint, minint), 0))
+assert(eqT(math.fmod(maxint, maxint), 0))
+assert(eqT(math.fmod(minint + 1, minint), minint + 1))
+assert(eqT(math.fmod(maxint - 1, maxint), maxint - 1))
+
+checkerror("zero", math.fmod, 3, 0)
+
+
+do    -- testing max/min
+  checkerror("value expected", math.max)
+  checkerror("value expected", math.min)
+  assert(eqT(math.max(3), 3))
+  assert(eqT(math.max(3, 5, 9, 1), 9))
+  assert(math.max(maxint, 10e60) == 10e60)
+  assert(eqT(math.max(minint, minint + 1), minint + 1))
+  assert(eqT(math.min(3), 3))
+  assert(eqT(math.min(3, 5, 9, 1), 1))
+  assert(math.min(3.2, 5.9, -9.2, 1.1) == -9.2)
+  assert(math.min(1.9, 1.7, 1.72) == 1.7)
+  assert(math.min(-10e60, minint) == -10e60)
+  assert(eqT(math.min(maxint, maxint - 1), maxint - 1))
+  assert(eqT(math.min(maxint - 2, maxint, maxint - 1), maxint - 2))
+end
+-- testing implicit conversions
+
+local a,b = '10', '20'
+assert(a*b == 200 and a+b == 30 and a-b == -10 and a/b == 0.5 and -b == -20)
+assert(a == '10' and b == '20')
+
+
+do
+  print("testing -0 and NaN")
+  local mz <const> = -0.0
+  local z <const> = 0.0
+  assert(mz == z)
+  assert(1/mz < 0 and 0 < 1/z)
+  local a = {[mz] = 1}
+  assert(a[z] == 1 and a[mz] == 1)
+  a[z] = 2
+  assert(a[z] == 2 and a[mz] == 2)
+  local inf = math.huge * 2 + 1
+  local mz <const> = -1/inf
+  local z <const> = 1/inf
+  assert(mz == z)
+  assert(1/mz < 0 and 0 < 1/z)
+  local NaN <const> = inf - inf
+  assert(NaN ~= NaN)
+  assert(not (NaN < NaN))
+  assert(not (NaN <= NaN))
+  assert(not (NaN > NaN))
+  assert(not (NaN >= NaN))
+  assert(not (0 < NaN) and not (NaN < 0))
+  local NaN1 <const> = 0/0
+  assert(NaN ~= NaN1 and not (NaN <= NaN1) and not (NaN1 <= NaN))
+  local a = {}
+  assert(not pcall(rawset, a, NaN, 1))
+  assert(a[NaN] == undef)
+  a[1] = 1
+  assert(not pcall(rawset, a, NaN, 1))
+  assert(a[NaN] == undef)
+  -- strings with same binary representation as 0.0 (might create problems
+  -- for constant manipulation in the pre-compiler)
+  local a1, a2, a3, a4, a5 = 0, 0, "\0\0\0\0\0\0\0\0", 0, "\0\0\0\0\0\0\0\0"
+  assert(a1 == a2 and a2 == a4 and a1 ~= a3)
+  assert(a3 == a5)
+end
+
+
+print("testing 'math.random'")
+
+local random, max, min = math.random, math.max, math.min
+
+local function testnear (val, ref, tol)
+  return (math.abs(val - ref) < ref * tol)
+end
+
+
+-- low-level!! For the current implementation of random in Lua,
+-- the first call after seed 1007 should return 0x7a7040a5a323c9d6
+do
+  -- all computations should work with 32-bit integers
+  local h <const> = 0x7a7040a5   -- higher half
+  local l <const> = 0xa323c9d6   -- lower half
+
+  math.randomseed(1007)
+  -- get the low 'intbits' of the 64-bit expected result
+  local res = (h << 32 | l) & ~(~0 << intbits)
+  assert(random(0) == res)
+
+  math.randomseed(1007, 0)
+  -- using higher bits to generate random floats; (the '% 2^32' converts
+  -- 32-bit integers to floats as unsigned)
+  local res
+  if floatbits <= 32 then
+    -- get all bits from the higher half
+    res = (h >> (32 - floatbits)) % 2^32
+  else
+    -- get 32 bits from the higher half and the rest from the lower half
+    res = (h % 2^32) * 2^(floatbits - 32) + ((l >> (64 - floatbits)) % 2^32)
+  end
+  local rand = random()
+  assert(eq(rand, 0x0.7a7040a5a323c9d6, 2^-floatbits))
+  assert(rand * 2^floatbits == res)
+end
+
+do
+  -- testing return of 'randomseed'
+  local x, y = math.randomseed()
+  local res = math.random(0)
+  x, y = math.randomseed(x, y)    -- should repeat the state
+  assert(math.random(0) == res)
+  math.randomseed(x, y)    -- again should repeat the state
+  assert(math.random(0) == res)
+  -- keep the random seed for following tests
+end
+
+do   -- test random for floats
+  local randbits = math.min(floatbits, 64)   -- at most 64 random bits
+  local mult = 2^randbits      -- to make random float into an integral
+  local counts = {}    -- counts for bits
+  for i = 1, randbits do counts[i] = 0 end
+  local up = -math.huge
+  local low = math.huge
+  local rounds = 100 * randbits   -- 100 times for each bit
+  local totalrounds = 0
+  ::doagain::   -- will repeat test until we get good statistics
+  for i = 0, rounds do
+    local t = random()
+    assert(0 <= t and t < 1)
+    up = max(up, t)
+    low = min(low, t)
+    assert(t * mult % 1 == 0)    -- no extra bits
+    local bit = i % randbits     -- bit to be tested
+    if (t * 2^bit) % 1 >= 0.5 then    -- is bit set?
+      counts[bit + 1] = counts[bit + 1] + 1   -- increment its count
+    end
+  end
+  totalrounds = totalrounds + rounds
+  if not (eq(up, 1, 0.001) and eq(low, 0, 0.001)) then
+    goto doagain
+  end
+  -- all bit counts should be near 50%
+  local expected = (totalrounds / randbits / 2)
+  for i = 1, randbits do
+    if not testnear(counts[i], expected, 0.10) then
+      goto doagain
+    end
+  end
+  print(string.format("float random range in %d calls: [%f, %f]",
+                      totalrounds, low, up))
+end
+
+
+do   -- test random for full integers
+  local up = 0
+  local low = 0
+  local counts = {}    -- counts for bits
+  for i = 1, intbits do counts[i] = 0 end
+  local rounds = 100 * intbits   -- 100 times for each bit
+  local totalrounds = 0
+  ::doagain::   -- will repeat test until we get good statistics
+  for i = 0, rounds do
+    local t = random(0)
+    up = max(up, t)
+    low = min(low, t)
+    local bit = i % intbits     -- bit to be tested
+    -- increment its count if it is set
+    counts[bit + 1] = counts[bit + 1] + ((t >> bit) & 1)
+  end
+  totalrounds = totalrounds + rounds
+  local lim = maxint >> 10
+  if not (maxint - up < lim and low - minint < lim) then
+    goto doagain
+  end
+  -- all bit counts should be near 50%
+  local expected = (totalrounds / intbits / 2)
+  for i = 1, intbits do
+    if not testnear(counts[i], expected, 0.10) then
+      goto doagain
+    end
+  end
+  print(string.format(
+     "integer random range in %d calls: [minint + %.0fppm, maxint - %.0fppm]",
+      totalrounds, (minint - low) / minint * 1e6,
+                   (maxint - up) / maxint * 1e6))
+end
+
+do
+  -- test distribution for a dice
+  local count = {0, 0, 0, 0, 0, 0}
+  local rep = 200
+  local totalrep = 0
+  ::doagain::
+  for i = 1, rep * 6 do
+    local r = random(6)
+    count[r] = count[r] + 1
+  end
+  totalrep = totalrep + rep
+  for i = 1, 6 do
+    if not testnear(count[i], totalrep, 0.05) then
+      goto doagain
+    end
+  end
+end
+
+do
+  local function aux (x1, x2)     -- test random for small intervals
+    local mark = {}; local count = 0   -- to check that all values appeared
+    while true do
+      local t = random(x1, x2)
+      assert(x1 <= t and t <= x2)
+      if not mark[t] then  -- new value
+        mark[t] = true
+        count = count + 1
+        if count == x2 - x1 + 1 then   -- all values appeared; OK
+          goto ok
+        end
+      end
+    end
+   ::ok::
+  end
+
+  aux(-10,0)
+  aux(1, 6)
+  aux(1, 2)
+  aux(1, 13)
+  aux(1, 31)
+  aux(1, 32)
+  aux(1, 33)
+  aux(-10, 10)
+  aux(-10,-10)   -- unit set
+  aux(minint, minint)   -- unit set
+  aux(maxint, maxint)   -- unit set
+  aux(minint, minint + 9)
+  aux(maxint - 3, maxint)
+end
+
+do
+  local function aux(p1, p2)       -- test random for large intervals
+    local max = minint
+    local min = maxint
+    local n = 100
+    local mark = {}; local count = 0   -- to count how many different values
+    ::doagain::
+    for _ = 1, n do
+      local t = random(p1, p2)
+      if not mark[t] then  -- new value
+        assert(p1 <= t and t <= p2)
+        max = math.max(max, t)
+        min = math.min(min, t)
+        mark[t] = true
+        count = count + 1
+      end
+    end
+    -- at least 80% of values are different
+    if not (count >= n * 0.8) then
+      goto doagain
+    end
+    -- min and max not too far from formal min and max
+    local diff = (p2 - p1) >> 4
+    if not (min < p1 + diff and max > p2 - diff) then
+      goto doagain
+    end
+  end
+  aux(0, maxint)
+  aux(1, maxint)
+  aux(3, maxint // 3)
+  aux(minint, -1)
+  aux(minint // 2, maxint // 2)
+  aux(minint, maxint)
+  aux(minint + 1, maxint)
+  aux(minint, maxint - 1)
+  aux(0, 1 << (intbits - 5))
+end
+
+
+assert(not pcall(random, 1, 2, 3))    -- too many arguments
+
+-- empty interval
+assert(not pcall(random, minint + 1, minint))
+assert(not pcall(random, maxint, maxint - 1))
+assert(not pcall(random, maxint, minint))
+
+
+
+print('OK')
diff --git a/test/external/lua-5.4.0-tests/nextvar.lua b/test/external/lua-5.4.0-tests/nextvar.lua
new file mode 100644
index 0000000..73af77d
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/nextvar.lua
@@ -0,0 +1,733 @@
+-- $Id: testes/nextvar.lua $
+-- See Copyright Notice in file all.lua
+
+print('testing tables, next, and for')
+
+local function checkerror (msg, f, ...)
+  local s, err = pcall(f, ...)
+  assert(not s and string.find(err, msg))
+end
+
+
+local a = {}
+
+-- make sure table has lots of space in hash part
+for i=1,100 do a[i.."+"] = true end
+for i=1,100 do a[i.."+"] = undef end
+-- fill hash part with numeric indices testing size operator
+for i=1,100 do
+  a[i] = true
+  assert(#a == i)
+end
+
+-- testing ipairs
+local x = 0
+for k,v in ipairs{10,20,30;x=12} do
+  x = x + 1
+  assert(k == x and v == x * 10)
+end
+
+for _ in ipairs{x=12, y=24} do assert(nil) end
+
+-- test for 'false' x ipair
+x = false
+local i = 0
+for k,v in ipairs{true,false,true,false} do
+  i = i + 1
+  x = not x
+  assert(x == v)
+end
+assert(i == 4)
+
+-- iterator function is always the same
+assert(type(ipairs{}) == 'function' and ipairs{} == ipairs{})
+
+
+if not T then
+  (Message or print)
+    ('\n >>> testC not active: skipping tests for table sizes <<<\n')
+else --[
+-- testing table sizes
+
+
+local function mp2 (n)   -- minimum power of 2 >= n
+  local mp = 2^math.ceil(math.log(n, 2))
+  assert(n == 0 or (mp/2 < n and n <= mp))
+  return mp
+end
+
+
+local function check (t, na, nh)
+  local a, h = T.querytab(t)
+  if a ~= na or h ~= nh then
+    print(na, nh, a, h)
+    assert(nil)
+  end
+end
+
+
+-- testing C library sizes
+do
+  local s = 0
+  for _ in pairs(math) do s = s + 1 end
+  check(math, 0, mp2(s))
+end
+
+
+-- testing constructor sizes
+local sizes = {0, 1, 2, 3, 4, 5, 7, 8, 9, 15, 16, 17,
+  30, 31, 32, 33, 34, 254, 255, 256, 500, 1000}
+
+for _, sa in ipairs(sizes) do    -- 'sa' is size of the array part
+  local arr = {"return {"}
+  for i = 1, sa do arr[1 + i] = "1," end    -- build array part
+  for _, sh in ipairs(sizes) do    -- 'sh' is size of the hash part
+    for j = 1, sh do   -- build hash part
+      arr[1 + sa + j] = string.format('k%x=%d,', j, j)
+    end
+    arr[1 + sa + sh + 1] = "}"
+    local prog = table.concat(arr)
+    local f = assert(load(prog))
+    f()    -- call once to ensure stack space
+    -- make sure table is not resized after being created
+    if sa == 0 or sh == 0 then
+      T.alloccount(2);  -- header + array or hash part
+    else
+      T.alloccount(3);  -- header + array part + hash part
+    end
+    local t = f()
+    T.alloccount();
+    assert(#t == sa)
+    check(t, sa, mp2(sh))
+  end
+end
+
+
+-- tests with unknown number of elements
+local a = {}
+for i=1,sizes[#sizes] do a[i] = i end   -- build auxiliary table
+for k in ipairs(sizes) do
+  local t = {table.unpack(a,1,k)}
+  assert(#t == k)
+  check(t, k, 0)
+  t = {1,2,3,table.unpack(a,1,k)}
+  check(t, k+3, 0)
+  assert(#t == k + 3)
+end
+
+
+-- testing tables dynamically built
+local lim = 130
+local a = {}; a[2] = 1; check(a, 0, 1)
+a = {}; a[0] = 1; check(a, 0, 1); a[2] = 1; check(a, 0, 2)
+a = {}; a[0] = 1; a[1] = 1; check(a, 1, 1)
+a = {}
+for i = 1,lim do
+  a[i] = 1
+  assert(#a == i)
+  check(a, mp2(i), 0)
+end
+
+a = {}
+for i = 1,lim do
+  a['a'..i] = 1
+  assert(#a == 0)
+  check(a, 0, mp2(i))
+end
+
+a = {}
+for i=1,16 do a[i] = i end
+check(a, 16, 0)
+do
+  for i=1,11 do a[i] = undef end
+  for i=30,50 do a[i] = true; a[i] = undef end   -- force a rehash (?)
+  check(a, 0, 8)   -- 5 elements in the table
+  a[10] = 1
+  for i=30,50 do a[i] = true; a[i] = undef end   -- force a rehash (?)
+  check(a, 0, 8)   -- only 6 elements in the table
+  for i=1,14 do a[i] = true; a[i] = undef end
+  for i=18,50 do a[i] = true; a[i] = undef end   -- force a rehash (?)
+  check(a, 0, 4)   -- only 2 elements ([15] and [16])
+end
+
+-- reverse filling
+for i=1,lim do
+  local a = {}
+  for i=i,1,-1 do a[i] = i end   -- fill in reverse
+  check(a, mp2(i), 0)
+end
+
+-- size tests for vararg
+lim = 35
+function foo (n, ...)
+  local arg = {...}
+  check(arg, n, 0)
+  assert(select('#', ...) == n)
+  arg[n+1] = true
+  check(arg, mp2(n+1), 0)
+  arg.x = true
+  check(arg, mp2(n+1), 1)
+end
+local a = {}
+for i=1,lim do a[i] = true; foo(i, table.unpack(a)) end
+
+
+-- Table length with limit smaller than maximum value at array
+local a = {}
+for i = 1,64 do a[i] = true end    -- make its array size 64
+for i = 1,64 do a[i] = nil end     -- erase all elements
+assert(T.querytab(a) == 64)    -- array part has 64 elements
+a[32] = true; a[48] = true;    -- binary search will find these ones
+a[51] = true                   -- binary search will miss this one
+assert(#a == 48)               -- this will set the limit
+assert(select(4, T.querytab(a)) == 48)  -- this is the limit now
+a[50] = true                   -- this will set a new limit
+assert(select(4, T.querytab(a)) == 50)  -- this is the limit now
+-- but the size is larger (and still inside the array part)
+assert(#a == 51)
+
+end  --]
+
+
+-- test size operation on tables with nils
+assert(#{} == 0)
+assert(#{nil} == 0)
+assert(#{nil, nil} == 0)
+assert(#{nil, nil, nil} == 0)
+assert(#{nil, nil, nil, nil} == 0)
+assert(#{1, 2, 3, nil, nil} == 3)
+print'+'
+
+
+local nofind = {}
+
+a,b,c = 1,2,3
+a,b,c = nil
+
+
+-- next uses always the same iteraction function
+assert(next{} == next{})
+
+local function find (name)
+  local n,v
+  while 1 do
+    n,v = next(_G, n)
+    if not n then return nofind end
+    assert(_G[n] ~= undef)
+    if n == name then return v end
+  end
+end
+
+local function find1 (name)
+  for n,v in pairs(_G) do
+    if n==name then return v end
+  end
+  return nil  -- not found
+end
+
+
+assert(print==find("print") and print == find1("print"))
+assert(_G["print"]==find("print"))
+assert(assert==find1("assert"))
+assert(nofind==find("return"))
+assert(not find1("return"))
+_G["ret" .. "urn"] = undef
+assert(nofind==find("return"))
+_G["xxx"] = 1
+assert(xxx==find("xxx"))
+
+-- invalid key to 'next'
+checkerror("invalid key", next, {10,20}, 3)
+
+-- both 'pairs' and 'ipairs' need an argument
+checkerror("bad argument", pairs)
+checkerror("bad argument", ipairs)
+
+print('+')
+
+a = {}
+for i=0,10000 do
+  if math.fmod(i,10) ~= 0 then
+    a['x'..i] = i
+  end
+end
+
+n = {n=0}
+for i,v in pairs(a) do
+  n.n = n.n+1
+  assert(i and v and a[i] == v)
+end
+assert(n.n == 9000)
+a = nil
+
+do   -- clear global table
+  local a = {}
+  for n,v in pairs(_G) do a[n]=v end
+  for n,v in pairs(a) do
+    if not package.loaded[n] and type(v) ~= "function" and
+       not string.find(n, "^[%u_]") then
+      _G[n] = undef
+    end
+    collectgarbage()
+  end
+end
+
+
+--
+
+local function checknext (a)
+  local b = {}
+  do local k,v = next(a); while k do b[k] = v; k,v = next(a,k) end end
+  for k,v in pairs(b) do assert(a[k] == v) end
+  for k,v in pairs(a) do assert(b[k] == v) end
+end
+
+checknext{1,x=1,y=2,z=3}
+checknext{1,2,x=1,y=2,z=3}
+checknext{1,2,3,x=1,y=2,z=3}
+checknext{1,2,3,4,x=1,y=2,z=3}
+checknext{1,2,3,4,5,x=1,y=2,z=3}
+
+assert(#{} == 0)
+assert(#{[-1] = 2} == 0)
+for i=0,40 do
+  local a = {}
+  for j=1,i do a[j]=j end
+  assert(#a == i)
+end
+
+-- 'maxn' is now deprecated, but it is easily defined in Lua
+function table.maxn (t)
+  local max = 0
+  for k in pairs(t) do
+    max = (type(k) == 'number') and math.max(max, k) or max
+  end
+  return max
+end
+
+assert(table.maxn{} == 0)
+assert(table.maxn{["1000"] = true} == 0)
+assert(table.maxn{["1000"] = true, [24.5] = 3} == 24.5)
+assert(table.maxn{[1000] = true} == 1000)
+assert(table.maxn{[10] = true, [100*math.pi] = print} == 100*math.pi)
+
+table.maxn = nil
+
+-- int overflow
+a = {}
+for i=0,50 do a[2^i] = true end
+assert(a[#a])
+
+print('+')
+
+
+do    -- testing 'next' with all kinds of keys
+  local a = {
+    [1] = 1,                        -- integer
+    [1.1] = 2,                      -- float
+    ['x'] = 3,                      -- short string
+    [string.rep('x', 1000)] = 4,    -- long string
+    [print] = 5,                    -- C function
+    [checkerror] = 6,               -- Lua function
+    [coroutine.running()] = 7,      -- thread
+    [true] = 8,                     -- boolean
+    [io.stdin] = 9,                 -- userdata
+    [{}] = 10,                      -- table
+  }
+  local b = {}; for i = 1, 10 do b[i] = true end
+  for k, v in pairs(a) do
+    assert(b[v]); b[v] = undef
+  end
+  assert(next(b) == nil)        -- 'b' now is empty
+end
+
+
+-- erasing values
+local t = {[{1}] = 1, [{2}] = 2, [string.rep("x ", 4)] = 3,
+           [100.3] = 4, [4] = 5}
+
+local n = 0
+for k, v in pairs( t ) do
+  n = n+1
+  assert(t[k] == v)
+  t[k] = undef
+  collectgarbage()
+  assert(t[k] == undef)
+end
+assert(n == 5)
+
+
+local function test (a)
+  assert(not pcall(table.insert, a, 2, 20));
+  table.insert(a, 10); table.insert(a, 2, 20);
+  table.insert(a, 1, -1); table.insert(a, 40);
+  table.insert(a, #a+1, 50)
+  table.insert(a, 2, -2)
+  assert(a[2] ~= undef)
+  assert(a["2"] == undef)
+  assert(not pcall(table.insert, a, 0, 20));
+  assert(not pcall(table.insert, a, #a + 2, 20));
+  assert(table.remove(a,1) == -1)
+  assert(table.remove(a,1) == -2)
+  assert(table.remove(a,1) == 10)
+  assert(table.remove(a,1) == 20)
+  assert(table.remove(a,1) == 40)
+  assert(table.remove(a,1) == 50)
+  assert(table.remove(a,1) == nil)
+  assert(table.remove(a) == nil)
+  assert(table.remove(a, #a) == nil)
+end
+
+a = {n=0, [-7] = "ban"}
+test(a)
+assert(a.n == 0 and a[-7] == "ban")
+
+a = {[-7] = "ban"};
+test(a)
+assert(a.n == nil and #a == 0 and a[-7] == "ban")
+
+a = {[-1] = "ban"}
+test(a)
+assert(#a == 0 and table.remove(a) == nil and a[-1] == "ban")
+
+a = {[0] = "ban"}
+assert(#a == 0 and table.remove(a) == "ban" and a[0] == undef)
+
+table.insert(a, 1, 10); table.insert(a, 1, 20); table.insert(a, 1, -1)
+assert(table.remove(a) == 10)
+assert(table.remove(a) == 20)
+assert(table.remove(a) == -1)
+assert(table.remove(a) == nil)
+
+a = {'c', 'd'}
+table.insert(a, 3, 'a')
+table.insert(a, 'b')
+assert(table.remove(a, 1) == 'c')
+assert(table.remove(a, 1) == 'd')
+assert(table.remove(a, 1) == 'a')
+assert(table.remove(a, 1) == 'b')
+assert(table.remove(a, 1) == nil)
+assert(#a == 0 and a.n == nil)
+
+a = {10,20,30,40}
+assert(table.remove(a, #a + 1) == nil)
+assert(not pcall(table.remove, a, 0))
+assert(a[#a] == 40)
+assert(table.remove(a, #a) == 40)
+assert(a[#a] == 30)
+assert(table.remove(a, 2) == 20)
+assert(a[#a] == 30 and #a == 2)
+
+do   -- testing table library with metamethods
+  local function test (proxy, t)
+    for i = 1, 10 do
+      table.insert(proxy, 1, i)
+    end
+    assert(#proxy == 10 and #t == 10 and proxy[1] ~= undef)
+    for i = 1, 10 do
+      assert(t[i] == 11 - i)
+    end
+    table.sort(proxy)
+    for i = 1, 10 do
+      assert(t[i] == i and proxy[i] == i)
+    end
+    assert(table.concat(proxy, ",") == "1,2,3,4,5,6,7,8,9,10")
+    for i = 1, 8 do
+      assert(table.remove(proxy, 1) == i)
+    end
+    assert(#proxy == 2 and #t == 2)
+    local a, b, c = table.unpack(proxy)
+    assert(a == 9 and b == 10 and c == nil)
+  end
+
+  -- all virtual
+  local t = {}
+  local proxy = setmetatable({}, {
+    __len = function () return #t end,
+    __index = t,
+    __newindex = t,
+  })
+  test(proxy, t)
+
+  -- only __newindex
+  local count = 0
+  t = setmetatable({}, {
+    __newindex = function (t,k,v) count = count + 1; rawset(t,k,v) end})
+  test(t, t)
+  assert(count == 10)   -- after first 10, all other sets are not new
+
+  -- no __newindex
+  t = setmetatable({}, {
+    __index = function (_,k) return k + 1 end,
+    __len = function (_) return 5 end})
+  assert(table.concat(t, ";") == "2;3;4;5;6")
+
+end
+
+
+if not T then
+  (Message or print)
+    ('\n >>> testC not active: skipping tests for table library on non-tables <<<\n')
+else --[
+  local debug = require'debug'
+  local tab = {10, 20, 30}
+  local mt = {}
+  local u = T.newuserdata(0)
+  checkerror("table expected", table.insert, u, 40)
+  checkerror("table expected", table.remove, u)
+  debug.setmetatable(u, mt)
+  checkerror("table expected", table.insert, u, 40)
+  checkerror("table expected", table.remove, u)
+  mt.__index = tab
+  checkerror("table expected", table.insert, u, 40)
+  checkerror("table expected", table.remove, u)
+  mt.__newindex = tab
+  checkerror("table expected", table.insert, u, 40)
+  checkerror("table expected", table.remove, u)
+  mt.__len = function () return #tab end
+  table.insert(u, 40)
+  assert(#u == 4 and #tab == 4 and u[4] == 40 and tab[4] == 40)
+  assert(table.remove(u) == 40)
+  table.insert(u, 1, 50)
+  assert(#u == 4 and #tab == 4 and u[4] == 30 and tab[1] == 50)
+
+  mt.__newindex = nil
+  mt.__len = nil
+  local tab2 = {}
+  local u2 = T.newuserdata(0)
+  debug.setmetatable(u2, {__newindex = function (_, k, v) tab2[k] = v end})
+  table.move(u, 1, 4, 1, u2)
+  assert(#tab2 == 4 and tab2[1] == tab[1] and tab2[4] == tab[4])
+
+end -- ]
+
+print('+')
+
+a = {}
+for i=1,1000 do
+  a[i] = i; a[i - 1] = undef
+end
+assert(next(a,nil) == 1000 and next(a,1000) == nil)
+
+assert(next({}) == nil)
+assert(next({}, nil) == nil)
+
+for a,b in pairs{} do error"not here" end
+for i=1,0 do error'not here' end
+for i=0,1,-1 do error'not here' end
+a = nil; for i=1,1 do assert(not a); a=1 end; assert(a)
+a = nil; for i=1,1,-1 do assert(not a); a=1 end; assert(a)
+
+do
+  print("testing floats in numeric for")
+  local a
+  -- integer count
+  a = 0; for i=1, 1, 1 do a=a+1 end; assert(a==1)
+  a = 0; for i=10000, 1e4, -1 do a=a+1 end; assert(a==1)
+  a = 0; for i=1, 0.99999, 1 do a=a+1 end; assert(a==0)
+  a = 0; for i=9999, 1e4, -1 do a=a+1 end; assert(a==0)
+  a = 0; for i=1, 0.99999, -1 do a=a+1 end; assert(a==1)
+
+  -- float count
+  a = 0; for i=0, 0.999999999, 0.1 do a=a+1 end; assert(a==10)
+  a = 0; for i=1.0, 1, 1 do a=a+1 end; assert(a==1)
+  a = 0; for i=-1.5, -1.5, 1 do a=a+1 end; assert(a==1)
+  a = 0; for i=1e6, 1e6, -1 do a=a+1 end; assert(a==1)
+  a = 0; for i=1.0, 0.99999, 1 do a=a+1 end; assert(a==0)
+  a = 0; for i=99999, 1e5, -1.0 do a=a+1 end; assert(a==0)
+  a = 0; for i=1.0, 0.99999, -1 do a=a+1 end; assert(a==1)
+end
+
+do   -- changing the control variable
+  local a
+  a = 0; for i = 1, 10 do a = a + 1; i = "x" end; assert(a == 10)
+  a = 0; for i = 10.0, 1, -1 do a = a + 1; i = "x" end; assert(a == 10)
+end
+
+-- conversion
+a = 0; for i="10","1","-2" do a=a+1 end; assert(a==5)
+
+do  -- checking types
+  local c
+  local function checkfloat (i)
+    assert(math.type(i) == "float")
+    c = c + 1
+  end
+
+  c = 0; for i = 1.0, 10 do checkfloat(i) end
+  assert(c == 10)
+
+  c = 0; for i = -1, -10, -1.0 do checkfloat(i) end
+  assert(c == 10)
+
+  local function checkint (i)
+    assert(math.type(i) == "integer")
+    c = c + 1
+  end
+
+  local m = math.maxinteger
+  c = 0; for i = m, m - 10, -1 do checkint(i) end
+  assert(c == 11)
+
+  c = 0; for i = 1, 10.9 do checkint(i) end
+  assert(c == 10)
+
+  c = 0; for i = 10, 0.001, -1 do checkint(i) end
+  assert(c == 10)
+
+  c = 0; for i = 1, "10.8" do checkint(i) end
+  assert(c == 10)
+
+  c = 0; for i = 9, "3.4", -1 do checkint(i) end
+  assert(c == 6)
+
+  c = 0; for i = 0, " -3.4  ", -1 do checkint(i) end
+  assert(c == 4)
+
+  c = 0; for i = 100, "96.3", -2 do checkint(i) end
+  assert(c == 2)
+
+  c = 0; for i = 1, math.huge do if i > 10 then break end; checkint(i) end
+  assert(c == 10)
+
+  c = 0; for i = -1, -math.huge, -1 do
+           if i < -10 then break end; checkint(i)
+          end
+  assert(c == 10)
+
+
+  for i = math.mininteger, -10e100 do assert(false) end
+  for i = math.maxinteger, 10e100, -1 do assert(false) end
+
+end
+
+
+do   -- testing other strange cases for numeric 'for'
+
+  local function checkfor (from, to, step, t)
+    local c = 0
+    for i = from, to, step do
+      c = c + 1
+      assert(i == t[c])
+    end
+    assert(c == #t)
+  end
+
+  local maxi = math.maxinteger
+  local mini = math.mininteger
+
+  checkfor(mini, maxi, maxi, {mini, -1, maxi - 1})
+
+  checkfor(mini, math.huge, maxi, {mini, -1, maxi - 1})
+
+  checkfor(maxi, mini, mini, {maxi, -1})
+
+  checkfor(maxi, mini, -maxi, {maxi, 0, -maxi})
+
+  checkfor(maxi, -math.huge, mini, {maxi, -1})
+
+  checkfor(maxi, mini, 1, {})
+  checkfor(mini, maxi, -1, {})
+
+  checkfor(maxi - 6, maxi, 3, {maxi - 6, maxi - 3, maxi})
+  checkfor(mini + 4, mini, -2, {mini + 4, mini + 2, mini})
+
+  local step = maxi // 10
+  local c = mini
+  for i = mini, maxi, step do
+    assert(i == c)
+    c = c + step
+  end
+
+  c = maxi
+  for i = maxi, mini, -step do
+    assert(i == c)
+    c = c - step
+  end
+
+  checkfor(maxi, maxi, maxi, {maxi})
+  checkfor(maxi, maxi, mini, {maxi})
+  checkfor(mini, mini, maxi, {mini})
+  checkfor(mini, mini, mini, {mini})
+end
+
+
+checkerror("'for' step is zero", function ()
+  for i = 1, 10, 0 do end
+end)
+
+checkerror("'for' step is zero", function ()
+  for i = 1, -10, 0 do end
+end)
+
+checkerror("'for' step is zero", function ()
+  for i = 1.0, -10, 0.0 do end
+end)
+
+collectgarbage()
+
+
+-- testing generic 'for'
+
+local function f (n, p)
+  local t = {}; for i=1,p do t[i] = i*10 end
+  return function (_, n, ...)
+           assert(select("#", ...) == 0)  -- no extra arguments
+           if n > 0 then
+             n = n-1
+             return n, table.unpack(t)
+           end
+         end, nil, n
+end
+
+local x = 0
+for n,a,b,c,d in f(5,3) do
+  x = x+1
+  assert(a == 10 and b == 20 and c == 30 and d == nil)
+end
+assert(x == 5)
+
+
+
+-- testing __pairs and __ipairs metamethod
+a = {}
+do
+  local x,y,z = pairs(a)
+  assert(type(x) == 'function' and y == a and z == nil)
+end
+
+local function foo (e,i)
+  assert(e == a)
+  if i <= 10 then return i+1, i+2 end
+end
+
+local function foo1 (e,i)
+  i = i + 1
+  assert(e == a)
+  if i <= e.n then return i,a[i] end
+end
+
+setmetatable(a, {__pairs = function (x) return foo, x, 0 end})
+
+local i = 0
+for k,v in pairs(a) do
+  i = i + 1
+  assert(k == i and v == k+1)
+end
+
+a.n = 5
+a[3] = 30
+
+-- testing ipairs with metamethods
+a = {n=10}
+setmetatable(a, { __index = function (t,k)
+                     if k <= t.n then return k * 10 end
+                  end})
+i = 0
+for k,v in ipairs(a) do
+  i = i + 1
+  assert(k == i and v == i * 10)
+end
+assert(i == a.n)
+
+print"OK"
diff --git a/test/external/lua-5.4.0-tests/pm.lua b/test/external/lua-5.4.0-tests/pm.lua
new file mode 100644
index 0000000..94bb63c
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/pm.lua
@@ -0,0 +1,421 @@
+-- $Id: testes/pm.lua $
+-- See Copyright Notice in file all.lua
+
+print('testing pattern matching')
+
+local function checkerror (msg, f, ...)
+  local s, err = pcall(f, ...)
+  assert(not s and string.find(err, msg))
+end
+
+
+function f(s, p)
+  local i,e = string.find(s, p)
+  if i then return string.sub(s, i, e) end
+end
+
+a,b = string.find('', '')    -- empty patterns are tricky
+assert(a == 1 and b == 0);
+a,b = string.find('alo', '')
+assert(a == 1 and b == 0)
+a,b = string.find('a\0o a\0o a\0o', 'a', 1)   -- first position
+assert(a == 1 and b == 1)
+a,b = string.find('a\0o a\0o a\0o', 'a\0o', 2)   -- starts in the midle
+assert(a == 5 and b == 7)
+a,b = string.find('a\0o a\0o a\0o', 'a\0o', 9)   -- starts in the midle
+assert(a == 9 and b == 11)
+a,b = string.find('a\0a\0a\0a\0\0ab', '\0ab', 2);  -- finds at the end
+assert(a == 9 and b == 11);
+a,b = string.find('a\0a\0a\0a\0\0ab', 'b')    -- last position
+assert(a == 11 and b == 11)
+assert(not string.find('a\0a\0a\0a\0\0ab', 'b\0'))   -- check ending
+assert(not string.find('', '\0'))
+assert(string.find('alo123alo', '12') == 4)
+assert(not string.find('alo123alo', '^12'))
+
+assert(string.match("aaab", ".*b") == "aaab")
+assert(string.match("aaa", ".*a") == "aaa")
+assert(string.match("b", ".*b") == "b")
+
+assert(string.match("aaab", ".+b") == "aaab")
+assert(string.match("aaa", ".+a") == "aaa")
+assert(not string.match("b", ".+b"))
+
+assert(string.match("aaab", ".?b") == "ab")
+assert(string.match("aaa", ".?a") == "aa")
+assert(string.match("b", ".?b") == "b")
+
+assert(f('aloALO', '%l*') == 'alo')
+assert(f('aLo_ALO', '%a*') == 'aLo')
+
+assert(f("  \n\r*&\n\r   xuxu  \n\n", "%g%g%g+") == "xuxu")
+
+assert(f('aaab', 'a*') == 'aaa');
+assert(f('aaa', '^.*$') == 'aaa');
+assert(f('aaa', 'b*') == '');
+assert(f('aaa', 'ab*a') == 'aa')
+assert(f('aba', 'ab*a') == 'aba')
+assert(f('aaab', 'a+') == 'aaa')
+assert(f('aaa', '^.+$') == 'aaa')
+assert(not f('aaa', 'b+'))
+assert(not f('aaa', 'ab+a'))
+assert(f('aba', 'ab+a') == 'aba')
+assert(f('a$a', '.$') == 'a')
+assert(f('a$a', '.%$') == 'a$')
+assert(f('a$a', '.$.') == 'a$a')
+assert(not f('a$a', '$$'))
+assert(not f('a$b', 'a$'))
+assert(f('a$a', '$') == '')
+assert(f('', 'b*') == '')
+assert(not f('aaa', 'bb*'))
+assert(f('aaab', 'a-') == '')
+assert(f('aaa', '^.-$') == 'aaa')
+assert(f('aabaaabaaabaaaba', 'b.*b') == 'baaabaaabaaab')
+assert(f('aabaaabaaabaaaba', 'b.-b') == 'baaab')
+assert(f('alo xo', '.o$') == 'xo')
+assert(f(' \n isto é assim', '%S%S*') == 'isto')
+assert(f(' \n isto é assim', '%S*$') == 'assim')
+assert(f(' \n isto é assim', '[a-z]*$') == 'assim')
+assert(f('um caracter ? extra', '[^%sa-z]') == '?')
+assert(f('', 'a?') == '')
+assert(f('á', 'á?') == 'á')
+assert(f('ábl', 'á?b?l?') == 'ábl')
+assert(f('  ábl', 'á?b?l?') == '')
+assert(f('aa', '^aa?a?a') == 'aa')
+assert(f(']]]áb', '[^]]') == 'á')
+assert(f("0alo alo", "%x*") == "0a")
+assert(f("alo alo", "%C+") == "alo alo")
+print('+')
+
+
+function f1(s, p)
+  p = string.gsub(p, "%%([0-9])", function (s)
+        return "%" .. (tonumber(s)+1)
+       end)
+  p = string.gsub(p, "^(^?)", "%1()", 1)
+  p = string.gsub(p, "($?)$", "()%1", 1)
+  local t = {string.match(s, p)}
+  return string.sub(s, t[1], t[#t] - 1)
+end
+
+assert(f1('alo alx 123 b\0o b\0o', '(..*) %1') == "b\0o b\0o")
+assert(f1('axz123= 4= 4 34', '(.+)=(.*)=%2 %1') == '3= 4= 4 3')
+assert(f1('=======', '^(=*)=%1$') == '=======')
+assert(not string.match('==========', '^([=]*)=%1$'))
+
+local function range (i, j)
+  if i <= j then
+    return i, range(i+1, j)
+  end
+end
+
+local abc = string.char(range(0, 127)) .. string.char(range(128, 255));
+
+assert(string.len(abc) == 256)
+
+function strset (p)
+  local res = {s=''}
+  string.gsub(abc, p, function (c) res.s = res.s .. c end)
+  return res.s
+end;
+
+assert(string.len(strset('[\200-\210]')) == 11)
+
+assert(strset('[a-z]') == "abcdefghijklmnopqrstuvwxyz")
+assert(strset('[a-z%d]') == strset('[%da-uu-z]'))
+assert(strset('[a-]') == "-a")
+assert(strset('[^%W]') == strset('[%w]'))
+assert(strset('[]%%]') == '%]')
+assert(strset('[a%-z]') == '-az')
+assert(strset('[%^%[%-a%]%-b]') == '-[]^ab')
+assert(strset('%Z') == strset('[\1-\255]'))
+assert(strset('.') == strset('[\1-\255%z]'))
+print('+');
+
+assert(string.match("alo xyzK", "(%w+)K") == "xyz")
+assert(string.match("254 K", "(%d*)K") == "")
+assert(string.match("alo ", "(%w*)$") == "")
+assert(not string.match("alo ", "(%w+)$"))
+assert(string.find("(álo)", "%(á") == 1)
+local a, b, c, d, e = string.match("âlo alo", "^(((.).).* (%w*))$")
+assert(a == 'âlo alo' and b == 'âl' and c == 'â' and d == 'alo' and e == nil)
+a, b, c, d  = string.match('0123456789', '(.+(.?)())')
+assert(a == '0123456789' and b == '' and c == 11 and d == nil)
+print('+')
+
+assert(string.gsub('ülo ülo', 'ü', 'x') == 'xlo xlo')
+assert(string.gsub('alo úlo  ', ' +$', '') == 'alo úlo')  -- trim
+assert(string.gsub('  alo alo  ', '^%s*(.-)%s*$', '%1') == 'alo alo')  -- double trim
+assert(string.gsub('alo  alo  \n 123\n ', '%s+', ' ') == 'alo alo 123 ')
+t = "abç d"
+a, b = string.gsub(t, '(.)', '%1@')
+assert('@'..a == string.gsub(t, '', '@') and b == 5)
+a, b = string.gsub('abçd', '(.)', '%0@', 2)
+assert(a == 'a@b@çd' and b == 2)
+assert(string.gsub('alo alo', '()[al]', '%1') == '12o 56o')
+assert(string.gsub("abc=xyz", "(%w*)(%p)(%w+)", "%3%2%1-%0") ==
+              "xyz=abc-abc=xyz")
+assert(string.gsub("abc", "%w", "%1%0") == "aabbcc")
+assert(string.gsub("abc", "%w+", "%0%1") == "abcabc")
+assert(string.gsub('áéí', '$', '\0óú') == 'áéí\0óú')
+assert(string.gsub('', '^', 'r') == 'r')
+assert(string.gsub('', '$', 'r') == 'r')
+print('+')
+
+
+do   -- new (5.3.3) semantics for empty matches
+  assert(string.gsub("a b cd", " *", "-") == "-a-b-c-d-")
+
+  local res = ""
+  local sub = "a  \nbc\t\td"
+  local i = 1
+  for p, e in string.gmatch(sub, "()%s*()") do
+    res = res .. string.sub(sub, i, p - 1) .. "-"
+    i = e
+  end
+  assert(res == "-a-b-c-d-")
+end
+
+
+assert(string.gsub("um (dois) tres (quatro)", "(%(%w+%))", string.upper) ==
+            "um (DOIS) tres (QUATRO)")
+
+do
+  local function setglobal (n,v) rawset(_G, n, v) end
+  string.gsub("a=roberto,roberto=a", "(%w+)=(%w%w*)", setglobal)
+  assert(_G.a=="roberto" and _G.roberto=="a")
+end
+
+function f(a,b) return string.gsub(a,'.',b) end
+assert(string.gsub("trocar tudo em |teste|b| é |beleza|al|", "|([^|]*)|([^|]*)|", f) ==
+            "trocar tudo em bbbbb é alalalalalal")
+
+local function dostring (s) return load(s, "")() or "" end
+assert(string.gsub("alo $a='x'$ novamente $return a$",
+                   "$([^$]*)%$",
+                   dostring) == "alo  novamente x")
+
+x = string.gsub("$x=string.gsub('alo', '.', string.upper)$ assim vai para $return x$",
+         "$([^$]*)%$", dostring)
+assert(x == ' assim vai para ALO')
+
+t = {}
+s = 'a alo jose  joao'
+r = string.gsub(s, '()(%w+)()', function (a,w,b)
+      assert(string.len(w) == b-a);
+      t[a] = b-a;
+    end)
+assert(s == r and t[1] == 1 and t[3] == 3 and t[7] == 4 and t[13] == 4)
+
+
+function isbalanced (s)
+  return not string.find(string.gsub(s, "%b()", ""), "[()]")
+end
+
+assert(isbalanced("(9 ((8))(\0) 7) \0\0 a b ()(c)() a"))
+assert(not isbalanced("(9 ((8) 7) a b (\0 c) a"))
+assert(string.gsub("alo 'oi' alo", "%b''", '"') == 'alo " alo')
+
+
+local t = {"apple", "orange", "lime"; n=0}
+assert(string.gsub("x and x and x", "x", function () t.n=t.n+1; return t[t.n] end)
+        == "apple and orange and lime")
+
+t = {n=0}
+string.gsub("first second word", "%w%w*", function (w) t.n=t.n+1; t[t.n] = w end)
+assert(t[1] == "first" and t[2] == "second" and t[3] == "word" and t.n == 3)
+
+t = {n=0}
+assert(string.gsub("first second word", "%w+",
+         function (w) t.n=t.n+1; t[t.n] = w end, 2) == "first second word")
+assert(t[1] == "first" and t[2] == "second" and t[3] == undef)
+
+checkerror("invalid replacement value %(a table%)",
+            string.gsub, "alo", ".", {a = {}})
+checkerror("invalid capture index %%2", string.gsub, "alo", ".", "%2")
+checkerror("invalid capture index %%0", string.gsub, "alo", "(%0)", "a")
+checkerror("invalid capture index %%1", string.gsub, "alo", "(%1)", "a")
+checkerror("invalid use of '%%'", string.gsub, "alo", ".", "%x")
+
+
+if not _soft then
+  print("big strings")
+  local a = string.rep('a', 300000)
+  assert(string.find(a, '^a*.?$'))
+  assert(not string.find(a, '^a*.?b$'))
+  assert(string.find(a, '^a-.?$'))
+
+  -- bug in 5.1.2
+  a = string.rep('a', 10000) .. string.rep('b', 10000)
+  assert(not pcall(string.gsub, a, 'b'))
+end
+
+-- recursive nest of gsubs
+function rev (s)
+  return string.gsub(s, "(.)(.+)", function (c,s1) return rev(s1)..c end)
+end
+
+local x = "abcdef"
+assert(rev(rev(x)) == x)
+
+
+-- gsub with tables
+assert(string.gsub("alo alo", ".", {}) == "alo alo")
+assert(string.gsub("alo alo", "(.)", {a="AA", l=""}) == "AAo AAo")
+assert(string.gsub("alo alo", "(.).", {a="AA", l="K"}) == "AAo AAo")
+assert(string.gsub("alo alo", "((.)(.?))", {al="AA", o=false}) == "AAo AAo")
+
+assert(string.gsub("alo alo", "().", {'x','yy','zzz'}) == "xyyzzz alo")
+
+t = {}; setmetatable(t, {__index = function (t,s) return string.upper(s) end})
+assert(string.gsub("a alo b hi", "%w%w+", t) == "a ALO b HI")
+
+
+-- tests for gmatch
+local a = 0
+for i in string.gmatch('abcde', '()') do assert(i == a+1); a=i end
+assert(a==6)
+
+t = {n=0}
+for w in string.gmatch("first second word", "%w+") do
+      t.n=t.n+1; t[t.n] = w
+end
+assert(t[1] == "first" and t[2] == "second" and t[3] == "word")
+
+t = {3, 6, 9}
+for i in string.gmatch ("xuxx uu ppar r", "()(.)%2") do
+  assert(i == table.remove(t, 1))
+end
+assert(#t == 0)
+
+t = {}
+for i,j in string.gmatch("13 14 10 = 11, 15= 16, 22=23", "(%d+)%s*=%s*(%d+)") do
+  t[tonumber(i)] = tonumber(j)
+end
+a = 0
+for k,v in pairs(t) do assert(k+1 == v+0); a=a+1 end
+assert(a == 3)
+
+
+do   -- init parameter in gmatch
+  local s = 0
+  for k in string.gmatch("10 20 30", "%d+", 3) do
+    s = s + tonumber(k)
+  end
+  assert(s == 50)
+
+  s = 0
+  for k in string.gmatch("11 21 31", "%d+", -4) do
+    s = s + tonumber(k)
+  end
+  assert(s == 32)
+
+  -- there is an empty string at the end of the subject
+  s = 0
+  for k in string.gmatch("11 21 31", "%w*", 9) do
+    s = s + 1
+  end
+  assert(s == 1)
+
+  -- there are no empty strings after the end of the subject
+  s = 0
+  for k in string.gmatch("11 21 31", "%w*", 10) do
+    s = s + 1
+  end
+  assert(s == 0)
+end
+
+
+-- tests for `%f' (`frontiers')
+
+assert(string.gsub("aaa aa a aaa a", "%f[%w]a", "x") == "xaa xa x xaa x")
+assert(string.gsub("[[]] [][] [[[[", "%f[[].", "x") == "x[]] x]x] x[[[")
+assert(string.gsub("01abc45de3", "%f[%d]", ".") == ".01abc.45de.3")
+assert(string.gsub("01abc45 de3x", "%f[%D]%w", ".") == "01.bc45 de3.")
+assert(string.gsub("function", "%f[\1-\255]%w", ".") == ".unction")
+assert(string.gsub("function", "%f[^\1-\255]", ".") == "function.")
+
+assert(string.find("a", "%f[a]") == 1)
+assert(string.find("a", "%f[^%z]") == 1)
+assert(string.find("a", "%f[^%l]") == 2)
+assert(string.find("aba", "%f[a%z]") == 3)
+assert(string.find("aba", "%f[%z]") == 4)
+assert(not string.find("aba", "%f[%l%z]"))
+assert(not string.find("aba", "%f[^%l%z]"))
+
+local i, e = string.find(" alo aalo allo", "%f[%S].-%f[%s].-%f[%S]")
+assert(i == 2 and e == 5)
+local k = string.match(" alo aalo allo", "%f[%S](.-%f[%s].-%f[%S])")
+assert(k == 'alo ')
+
+local a = {1, 5, 9, 14, 17,}
+for k in string.gmatch("alo alo th02 is 1hat", "()%f[%w%d]") do
+  assert(table.remove(a, 1) == k)
+end
+assert(#a == 0)
+
+
+-- malformed patterns
+local function malform (p, m)
+  m = m or "malformed"
+  local r, msg = pcall(string.find, "a", p)
+  assert(not r and string.find(msg, m))
+end
+
+malform("(.", "unfinished capture")
+malform(".)", "invalid pattern capture")
+malform("[a")
+malform("[]")
+malform("[^]")
+malform("[a%]")
+malform("[a%")
+malform("%b")
+malform("%ba")
+malform("%")
+malform("%f", "missing")
+
+-- \0 in patterns
+assert(string.match("ab\0\1\2c", "[\0-\2]+") == "\0\1\2")
+assert(string.match("ab\0\1\2c", "[\0-\0]+") == "\0")
+assert(string.find("b$a", "$\0?") == 2)
+assert(string.find("abc\0efg", "%\0") == 4)
+assert(string.match("abc\0efg\0\1e\1g", "%b\0\1") == "\0efg\0\1e\1")
+assert(string.match("abc\0\0\0", "%\0+") == "\0\0\0")
+assert(string.match("abc\0\0\0", "%\0%\0?") == "\0\0")
+
+-- magic char after \0
+assert(string.find("abc\0\0","\0.") == 4)
+assert(string.find("abcx\0\0abc\0abc","x\0\0abc\0a.") == 4)
+
+
+do   -- test reuse of original string in gsub
+  local s = string.rep("a", 100)
+  local r = string.gsub(s, "b", "c")   -- no match
+  assert(string.format("%p", s) == string.format("%p", r))
+
+  r = string.gsub(s, ".", {x = "y"})   -- no substitutions
+  assert(string.format("%p", s) == string.format("%p", r))
+
+  local count = 0
+  r = string.gsub(s, ".", function (x)
+                            assert(x == "a")
+                            count = count + 1
+                            return nil    -- no substitution
+                          end)
+  r = string.gsub(r, ".", {b = 'x'})   -- "a" is not a key; no subst.
+  assert(count == 100)
+  assert(string.format("%p", s) == string.format("%p", r))
+
+  count = 0
+  r = string.gsub(s, ".", function (x)
+                            assert(x == "a")
+                            count = count + 1
+                            return x    -- substitution...
+                          end)
+  assert(count == 100)
+  -- no reuse in this case
+  assert(r == s and string.format("%p", s) ~= string.format("%p", r))
+end
+
+print('OK')
+
diff --git a/test/external/lua-5.4.0-tests/sort.lua b/test/external/lua-5.4.0-tests/sort.lua
new file mode 100644
index 0000000..ef405d9
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/sort.lua
@@ -0,0 +1,310 @@
+-- $Id: testes/sort.lua $
+-- See Copyright Notice in file all.lua
+
+print "testing (parts of) table library"
+
+print "testing unpack"
+
+local unpack = table.unpack
+
+local maxI = math.maxinteger
+local minI = math.mininteger
+
+
+local function checkerror (msg, f, ...)
+  local s, err = pcall(f, ...)
+  assert(not s and string.find(err, msg))
+end
+
+
+checkerror("wrong number of arguments", table.insert, {}, 2, 3, 4)
+
+local x,y,z,a,n
+a = {}; lim = _soft and 200 or 2000
+for i=1, lim do a[i]=i end
+assert(select(lim, unpack(a)) == lim and select('#', unpack(a)) == lim)
+x = unpack(a)
+assert(x == 1)
+x = {unpack(a)}
+assert(#x == lim and x[1] == 1 and x[lim] == lim)
+x = {unpack(a, lim-2)}
+assert(#x == 3 and x[1] == lim-2 and x[3] == lim)
+x = {unpack(a, 10, 6)}
+assert(next(x) == nil)   -- no elements
+x = {unpack(a, 11, 10)}
+assert(next(x) == nil)   -- no elements
+x,y = unpack(a, 10, 10)
+assert(x == 10 and y == nil)
+x,y,z = unpack(a, 10, 11)
+assert(x == 10 and y == 11 and z == nil)
+a,x = unpack{1}
+assert(a==1 and x==nil)
+a,x = unpack({1,2}, 1, 1)
+assert(a==1 and x==nil)
+
+do
+  local maxi = (1 << 31) - 1          -- maximum value for an int (usually)
+  local mini = -(1 << 31)             -- minimum value for an int (usually)
+  checkerror("too many results", unpack, {}, 0, maxi)
+  checkerror("too many results", unpack, {}, 1, maxi)
+  checkerror("too many results", unpack, {}, 0, maxI)
+  checkerror("too many results", unpack, {}, 1, maxI)
+  checkerror("too many results", unpack, {}, mini, maxi)
+  checkerror("too many results", unpack, {}, -maxi, maxi)
+  checkerror("too many results", unpack, {}, minI, maxI)
+  unpack({}, maxi, 0)
+  unpack({}, maxi, 1)
+  unpack({}, maxI, minI)
+  pcall(unpack, {}, 1, maxi + 1)
+  local a, b = unpack({[maxi] = 20}, maxi, maxi)
+  assert(a == 20 and b == nil)
+  a, b = unpack({[maxi] = 20}, maxi - 1, maxi)
+  assert(a == nil and b == 20)
+  local t = {[maxI - 1] = 12, [maxI] = 23}
+  a, b = unpack(t, maxI - 1, maxI); assert(a == 12 and b == 23)
+  a, b = unpack(t, maxI, maxI); assert(a == 23 and b == nil)
+  a, b = unpack(t, maxI, maxI - 1); assert(a == nil and b == nil)
+  t = {[minI] = 12.3, [minI + 1] = 23.5}
+  a, b = unpack(t, minI, minI + 1); assert(a == 12.3 and b == 23.5)
+  a, b = unpack(t, minI, minI); assert(a == 12.3 and b == nil)
+  a, b = unpack(t, minI + 1, minI); assert(a == nil and b == nil)
+end
+
+do   -- length is not an integer
+  local t = setmetatable({}, {__len = function () return 'abc' end})
+  assert(#t == 'abc')
+  checkerror("object length is not an integer", table.insert, t, 1)
+end
+
+print "testing pack"
+
+a = table.pack()
+assert(a[1] == undef and a.n == 0) 
+
+a = table.pack(table)
+assert(a[1] == table and a.n == 1)
+
+a = table.pack(nil, nil, nil, nil)
+assert(a[1] == nil and a.n == 4)
+
+
+-- testing move
+do
+
+  checkerror("table expected", table.move, 1, 2, 3, 4)
+
+  local function eqT (a, b)
+    for k, v in pairs(a) do assert(b[k] == v) end 
+    for k, v in pairs(b) do assert(a[k] == v) end 
+  end
+
+  local a = table.move({10,20,30}, 1, 3, 2)  -- move forward
+  eqT(a, {10,10,20,30})
+
+  -- move forward with overlap of 1
+  a = table.move({10, 20, 30}, 1, 3, 3)
+  eqT(a, {10, 20, 10, 20, 30})
+
+  -- moving to the same table (not being explicit about it)
+  a = {10, 20, 30, 40}
+  table.move(a, 1, 4, 2, a)
+  eqT(a, {10, 10, 20, 30, 40})
+
+  a = table.move({10,20,30}, 2, 3, 1)   -- move backward
+  eqT(a, {20,30,30})
+
+  a = {}   -- move to new table
+  assert(table.move({10,20,30}, 1, 3, 1, a) == a)
+  eqT(a, {10,20,30})
+
+  a = {}
+  assert(table.move({10,20,30}, 1, 0, 3, a) == a)  -- empty move (no move)
+  eqT(a, {})
+
+  a = table.move({10,20,30}, 1, 10, 1)   -- move to the same place
+  eqT(a, {10,20,30})
+
+  -- moving on the fringes
+  a = table.move({[maxI - 2] = 1, [maxI - 1] = 2, [maxI] = 3},
+                 maxI - 2, maxI, -10, {})
+  eqT(a, {[-10] = 1, [-9] = 2, [-8] = 3})
+
+  a = table.move({[minI] = 1, [minI + 1] = 2, [minI + 2] = 3},
+                 minI, minI + 2, -10, {})
+  eqT(a, {[-10] = 1, [-9] = 2, [-8] = 3})
+
+  a = table.move({45}, 1, 1, maxI)
+  eqT(a, {45, [maxI] = 45})
+
+  a = table.move({[maxI] = 100}, maxI, maxI, minI)
+  eqT(a, {[minI] = 100, [maxI] = 100})
+
+  a = table.move({[minI] = 100}, minI, minI, maxI)
+  eqT(a, {[minI] = 100, [maxI] = 100})
+
+  a = setmetatable({}, {
+        __index = function (_,k) return k * 10 end,
+        __newindex = error})
+  local b = table.move(a, 1, 10, 3, {})
+  eqT(a, {})
+  eqT(b, {nil,nil,10,20,30,40,50,60,70,80,90,100})
+
+  b = setmetatable({""}, {
+        __index = error,
+        __newindex = function (t,k,v)
+          t[1] = string.format("%s(%d,%d)", t[1], k, v)
+      end})
+  table.move(a, 10, 13, 3, b)
+  assert(b[1] == "(3,100)(4,110)(5,120)(6,130)")
+  local stat, msg = pcall(table.move, b, 10, 13, 3, b)
+  assert(not stat and msg == b)
+end
+
+do
+  -- for very long moves, just check initial accesses and interrupt
+  -- move with an error
+  local function checkmove (f, e, t, x, y)
+    local pos1, pos2
+    local a = setmetatable({}, {
+                __index = function (_,k) pos1 = k end,
+                __newindex = function (_,k) pos2 = k; error() end, })
+    local st, msg = pcall(table.move, a, f, e, t)
+    assert(not st and not msg and pos1 == x and pos2 == y)
+  end
+  checkmove(1, maxI, 0, 1, 0)
+  checkmove(0, maxI - 1, 1, maxI - 1, maxI)
+  checkmove(minI, -2, -5, -2, maxI - 6)
+  checkmove(minI + 1, -1, -2, -1, maxI - 3)
+  checkmove(minI, -2, 0, minI, 0)  -- non overlapping
+  checkmove(minI + 1, -1, 1, minI + 1, 1)  -- non overlapping
+end
+
+checkerror("too many", table.move, {}, 0, maxI, 1)
+checkerror("too many", table.move, {}, -1, maxI - 1, 1)
+checkerror("too many", table.move, {}, minI, -1, 1)
+checkerror("too many", table.move, {}, minI, maxI, 1)
+checkerror("wrap around", table.move, {}, 1, maxI, 2)
+checkerror("wrap around", table.move, {}, 1, 2, maxI)
+checkerror("wrap around", table.move, {}, minI, -2, 2)
+
+
+print"testing sort"
+
+
+-- strange lengths
+local a = setmetatable({}, {__len = function () return -1 end})
+assert(#a == -1)
+table.sort(a, error)    -- should not compare anything
+a = setmetatable({}, {__len = function () return maxI end})
+checkerror("too big", table.sort, a)
+
+-- test checks for invalid order functions
+local function check (t)
+  local function f(a, b) assert(a and b); return true end
+  checkerror("invalid order function", table.sort, t, f)
+end
+
+check{1,2,3,4}
+check{1,2,3,4,5}
+check{1,2,3,4,5,6}
+
+
+function check (a, f)
+  f = f or function (x,y) return x<y end;
+  for n = #a, 2, -1 do
+    assert(not f(a[n], a[n-1]))
+  end
+end
+
+a = {"Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep",
+     "Oct", "Nov", "Dec"}
+
+table.sort(a)
+check(a)
+
+function perm (s, n)
+  n = n or #s
+  if n == 1 then
+    local t = {unpack(s)}
+    table.sort(t)
+    check(t)
+  else
+    for i = 1, n do
+      s[i], s[n] = s[n], s[i]
+      perm(s, n - 1)
+      s[i], s[n] = s[n], s[i]
+    end
+  end
+end
+
+perm{}
+perm{1}
+perm{1,2}
+perm{1,2,3}
+perm{1,2,3,4}
+perm{2,2,3,4}
+perm{1,2,3,4,5}
+perm{1,2,3,3,5}
+perm{1,2,3,4,5,6}
+perm{2,2,3,3,5,6}
+
+function timesort (a, n, func, msg, pre)
+  local x = os.clock()
+  table.sort(a, func)
+  x = (os.clock() - x) * 1000
+  pre = pre or ""
+  print(string.format("%ssorting %d %s elements in %.2f msec.", pre, n, msg, x))
+  check(a, func)
+end
+
+limit = 50000
+if _soft then limit = 5000 end
+
+a = {}
+for i=1,limit do
+  a[i] = math.random()
+end
+
+timesort(a, limit, nil, "random")
+
+timesort(a, limit, nil, "sorted", "re-")
+
+a = {}
+for i=1,limit do
+  a[i] = math.random()
+end
+
+x = os.clock(); i=0
+table.sort(a, function(x,y) i=i+1; return y<x end)
+x = (os.clock() - x) * 1000
+print(string.format("Invert-sorting other %d elements in %.2f msec., with %i comparisons",
+      limit, x, i))
+check(a, function(x,y) return y<x end)
+
+
+table.sort{}  -- empty array
+
+for i=1,limit do a[i] = false end
+timesort(a, limit,  function(x,y) return nil end, "equal")
+
+for i,v in pairs(a) do assert(v == false) end
+
+A = {"álo", "\0first :-)", "alo", "then this one", "45", "and a new"}
+table.sort(A)
+check(A)
+
+table.sort(A, function (x, y)
+          load(string.format("A[%q] = ''", x), "")()
+          collectgarbage()
+          return x<y
+        end)
+
+
+tt = {__lt = function (a,b) return a.val < b.val end}
+a = {}
+for i=1,10 do  a[i] = {val=math.random(100)}; setmetatable(a[i], tt); end
+table.sort(a)
+check(a, tt.__lt)
+check(a)
+
+print"OK"
diff --git a/test/external/lua-5.4.0-tests/strings.lua b/test/external/lua-5.4.0-tests/strings.lua
new file mode 100644
index 0000000..4a10857
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/strings.lua
@@ -0,0 +1,495 @@
+-- $Id: testes/strings.lua $
+-- See Copyright Notice in file all.lua
+
+print('testing strings and string library')
+
+local maxi <const> = math.maxinteger
+local mini <const> = math.mininteger
+
+
+local function checkerror (msg, f, ...)
+  local s, err = pcall(f, ...)
+  assert(not s and string.find(err, msg))
+end
+
+
+-- testing string comparisons
+assert('alo' < 'alo1')
+assert('' < 'a')
+assert('alo\0alo' < 'alo\0b')
+assert('alo\0alo\0\0' > 'alo\0alo\0')
+assert('alo' < 'alo\0')
+assert('alo\0' > 'alo')
+assert('\0' < '\1')
+assert('\0\0' < '\0\1')
+assert('\1\0a\0a' <= '\1\0a\0a')
+assert(not ('\1\0a\0b' <= '\1\0a\0a'))
+assert('\0\0\0' < '\0\0\0\0')
+assert(not('\0\0\0\0' < '\0\0\0'))
+assert('\0\0\0' <= '\0\0\0\0')
+assert(not('\0\0\0\0' <= '\0\0\0'))
+assert('\0\0\0' <= '\0\0\0')
+assert('\0\0\0' >= '\0\0\0')
+assert(not ('\0\0b' < '\0\0a\0'))
+
+-- testing string.sub
+assert(string.sub("123456789",2,4) == "234")
+assert(string.sub("123456789",7) == "789")
+assert(string.sub("123456789",7,6) == "")
+assert(string.sub("123456789",7,7) == "7")
+assert(string.sub("123456789",0,0) == "")
+assert(string.sub("123456789",-10,10) == "123456789")
+assert(string.sub("123456789",1,9) == "123456789")
+assert(string.sub("123456789",-10,-20) == "")
+assert(string.sub("123456789",-1) == "9")
+assert(string.sub("123456789",-4) == "6789")
+assert(string.sub("123456789",-6, -4) == "456")
+assert(string.sub("123456789", mini, -4) == "123456")
+assert(string.sub("123456789", mini, maxi) == "123456789")
+assert(string.sub("123456789", mini, mini) == "")
+assert(string.sub("\000123456789",3,5) == "234")
+assert(("\000123456789"):sub(8) == "789")
+
+-- testing string.find
+assert(string.find("123456789", "345") == 3)
+a,b = string.find("123456789", "345")
+assert(string.sub("123456789", a, b) == "345")
+assert(string.find("1234567890123456789", "345", 3) == 3)
+assert(string.find("1234567890123456789", "345", 4) == 13)
+assert(not string.find("1234567890123456789", "346", 4))
+assert(string.find("1234567890123456789", ".45", -9) == 13)
+assert(not string.find("abcdefg", "\0", 5, 1))
+assert(string.find("", "") == 1)
+assert(string.find("", "", 1) == 1)
+assert(not string.find("", "", 2))
+assert(not string.find('', 'aaa', 1))
+assert(('alo(.)alo'):find('(.)', 1, 1) == 4)
+
+assert(string.len("") == 0)
+assert(string.len("\0\0\0") == 3)
+assert(string.len("1234567890") == 10)
+
+assert(#"" == 0)
+assert(#"\0\0\0" == 3)
+assert(#"1234567890" == 10)
+
+-- testing string.byte/string.char
+assert(string.byte("a") == 97)
+assert(string.byte("\xe4") > 127)
+assert(string.byte(string.char(255)) == 255)
+assert(string.byte(string.char(0)) == 0)
+assert(string.byte("\0") == 0)
+assert(string.byte("\0\0alo\0x", -1) == string.byte('x'))
+assert(string.byte("ba", 2) == 97)
+assert(string.byte("\n\n", 2, -1) == 10)
+assert(string.byte("\n\n", 2, 2) == 10)
+assert(string.byte("") == nil)
+assert(string.byte("hi", -3) == nil)
+assert(string.byte("hi", 3) == nil)
+assert(string.byte("hi", 9, 10) == nil)
+assert(string.byte("hi", 2, 1) == nil)
+assert(string.char() == "")
+assert(string.char(0, 255, 0) == "\0\255\0")
+assert(string.char(0, string.byte("\xe4"), 0) == "\0\xe4\0")
+assert(string.char(string.byte("\xe4l\0óu", 1, -1)) == "\xe4l\0óu")
+assert(string.char(string.byte("\xe4l\0óu", 1, 0)) == "")
+assert(string.char(string.byte("\xe4l\0óu", -10, 100)) == "\xe4l\0óu")
+
+checkerror("out of range", string.char, 256)
+checkerror("out of range", string.char, -1)
+checkerror("out of range", string.char, math.maxinteger)
+checkerror("out of range", string.char, math.mininteger)
+
+assert(string.upper("ab\0c") == "AB\0C")
+assert(string.lower("\0ABCc%$") == "\0abcc%$")
+assert(string.rep('teste', 0) == '')
+assert(string.rep('tés\00tê', 2) == 'tés\0têtés\000tê')
+assert(string.rep('', 10) == '')
+
+if string.packsize("i") == 4 then
+  -- result length would be 2^31 (int overflow)
+  checkerror("too large", string.rep, 'aa', (1 << 30))
+  checkerror("too large", string.rep, 'a', (1 << 30), ',')
+end
+
+-- repetitions with separator
+assert(string.rep('teste', 0, 'xuxu') == '')
+assert(string.rep('teste', 1, 'xuxu') == 'teste')
+assert(string.rep('\1\0\1', 2, '\0\0') == '\1\0\1\0\0\1\0\1')
+assert(string.rep('', 10, '.') == string.rep('.', 9))
+assert(not pcall(string.rep, "aa", maxi // 2 + 10))
+assert(not pcall(string.rep, "", maxi // 2 + 10, "aa"))
+
+assert(string.reverse"" == "")
+assert(string.reverse"\0\1\2\3" == "\3\2\1\0")
+assert(string.reverse"\0001234" == "4321\0")
+
+for i=0,30 do assert(string.len(string.rep('a', i)) == i) end
+
+assert(type(tostring(nil)) == 'string')
+assert(type(tostring(12)) == 'string')
+assert(string.find(tostring{}, 'table:'))
+assert(string.find(tostring(print), 'function:'))
+assert(#tostring('\0') == 1)
+assert(tostring(true) == "true")
+assert(tostring(false) == "false")
+assert(tostring(-1203) == "-1203")
+assert(tostring(1203.125) == "1203.125")
+assert(tostring(-0.5) == "-0.5")
+assert(tostring(-32767) == "-32767")
+if math.tointeger(2147483647) then   -- no overflow? (32 bits)
+  assert(tostring(-2147483647) == "-2147483647")
+end
+if math.tointeger(4611686018427387904) then   -- no overflow? (64 bits)
+  assert(tostring(4611686018427387904) == "4611686018427387904")
+  assert(tostring(-4611686018427387904) == "-4611686018427387904")
+end
+
+if tostring(0.0) == "0.0" then   -- "standard" coercion float->string
+  assert('' .. 12 == '12' and 12.0 .. '' == '12.0')
+  assert(tostring(-1203 + 0.0) == "-1203.0")
+else   -- compatible coercion
+  assert(tostring(0.0) == "0")
+  assert('' .. 12 == '12' and 12.0 .. '' == '12')
+  assert(tostring(-1203 + 0.0) == "-1203")
+end
+
+do  -- tests for '%p' format
+  -- not much to test, as C does not specify what '%p' does.
+  -- ("The value of the pointer is converted to a sequence of printing
+  -- characters, in an implementation-defined manner.")
+  local null = "(null)"    -- nulls are formatted by Lua
+  assert(string.format("%p", 4) == null)
+  assert(string.format("%p", true) == null)
+  assert(string.format("%p", nil) == null)
+  assert(string.format("%p", {}) ~= null)
+  assert(string.format("%p", print) ~= null)
+  assert(string.format("%p", coroutine.running()) ~= null)
+  assert(string.format("%p", io.stdin) ~= null)
+  assert(string.format("%p", io.stdin) == string.format("%p", io.stdin))
+  assert(string.format("%p", print) == string.format("%p", print))
+  assert(string.format("%p", print) ~= string.format("%p", assert))
+
+  assert(#string.format("%90p", {}) == 90)
+  assert(#string.format("%-60p", {}) == 60)
+  assert(string.format("%10p", false) == string.rep(" ", 10 - #null) .. null)
+  assert(string.format("%-12p", 1.5) == null .. string.rep(" ", 12 - #null))
+
+  do
+    local t1 = {}; local t2 = {}
+    assert(string.format("%p", t1) ~= string.format("%p", t2))
+  end
+
+  do     -- short strings are internalized
+    local s1 = string.rep("a", 10)
+    local s2 = string.rep("aa", 5)
+  assert(string.format("%p", s1) == string.format("%p", s2))
+  end
+
+  do     -- long strings aren't internalized
+    local s1 = string.rep("a", 300); local s2 = string.rep("a", 300)
+    assert(string.format("%p", s1) ~= string.format("%p", s2))
+  end
+end
+
+x = '"ílo"\n\\'
+assert(string.format('%q%s', x, x) == '"\\"ílo\\"\\\n\\\\""ílo"\n\\')
+assert(string.format('%q', "\0") == [["\0"]])
+assert(load(string.format('return %q', x))() == x)
+x = "\0\1\0023\5\0009"
+assert(load(string.format('return %q', x))() == x)
+assert(string.format("\0%c\0%c%x\0", string.byte("\xe4"), string.byte("b"), 140) ==
+              "\0\xe4\0b8c\0")
+assert(string.format('') == "")
+assert(string.format("%c",34)..string.format("%c",48)..string.format("%c",90)..string.format("%c",100) ==
+       string.format("%c%c%c%c", 34, 48, 90, 100))
+assert(string.format("%s\0 is not \0%s", 'not be', 'be') == 'not be\0 is not \0be')
+assert(string.format("%%%d %010d", 10, 23) == "%10 0000000023")
+assert(tonumber(string.format("%f", 10.3)) == 10.3)
+x = string.format('"%-50s"', 'a')
+assert(#x == 52)
+assert(string.sub(x, 1, 4) == '"a  ')
+
+assert(string.format("-%.20s.20s", string.rep("%", 2000)) ==
+                     "-"..string.rep("%", 20)..".20s")
+assert(string.format('"-%20s.20s"', string.rep("%", 2000)) ==
+       string.format("%q", "-"..string.rep("%", 2000)..".20s"))
+
+do
+  local function checkQ (v)
+    local s = string.format("%q", v)
+    local nv = load("return " .. s)()
+    assert(v == nv and math.type(v) == math.type(nv))
+  end
+  checkQ("\0\0\1\255\u{234}")
+  checkQ(math.maxinteger)
+  checkQ(math.mininteger)
+  checkQ(math.pi)
+  checkQ(0.1)
+  checkQ(true)
+  checkQ(nil)
+  checkQ(false)
+  checkQ(math.huge)
+  checkQ(-math.huge)
+  assert(string.format("%q", 0/0) == "(0/0)")   -- NaN
+  checkerror("no literal", string.format, "%q", {})
+end
+
+assert(string.format("\0%s\0", "\0\0\1") == "\0\0\0\1\0")
+checkerror("contains zeros", string.format, "%10s", "\0")
+checkerror("cannot have modifiers", string.format, "%10q", "1")
+
+-- format x tostring
+assert(string.format("%s %s", nil, true) == "nil true")
+assert(string.format("%s %.4s", false, true) == "false true")
+assert(string.format("%.3s %.3s", false, true) == "fal tru")
+local m = setmetatable({}, {__tostring = function () return "hello" end,
+                            __name = "hi"})
+assert(string.format("%s %.10s", m, m) == "hello hello")
+getmetatable(m).__tostring = nil   -- will use '__name' from now on
+assert(string.format("%.4s", m) == "hi: ")
+
+getmetatable(m).__tostring = function () return {} end
+checkerror("'__tostring' must return a string", tostring, m)
+
+
+assert(string.format("%x", 0.0) == "0")
+assert(string.format("%02x", 0.0) == "00")
+assert(string.format("%08X", 0xFFFFFFFF) == "FFFFFFFF")
+assert(string.format("%+08d", 31501) == "+0031501")
+assert(string.format("%+08d", -30927) == "-0030927")
+
+
+do    -- longest number that can be formatted
+  local i = 1
+  local j = 10000
+  while i + 1 < j do   -- binary search for maximum finite float
+    local m = (i + j) // 2
+    if 10^m < math.huge then i = m else j = m end
+  end
+  assert(10^i < math.huge and 10^j == math.huge)
+  local s = string.format('%.99f', -(10^i))
+  assert(string.len(s) >= i + 101)
+  assert(tonumber(s) == -(10^i))
+
+  -- limit for floats
+  assert(10^38 < math.huge)
+  local s = string.format('%.99f', -(10^38))
+  assert(string.len(s) >= 38 + 101)
+  assert(tonumber(s) == -(10^38))
+end
+
+
+-- testing large numbers for format
+do   -- assume at least 32 bits
+  local max, min = 0x7fffffff, -0x80000000    -- "large" for 32 bits
+  assert(string.sub(string.format("%8x", -1), -8) == "ffffffff")
+  assert(string.format("%x", max) == "7fffffff")
+  assert(string.sub(string.format("%x", min), -8) == "80000000")
+  assert(string.format("%d", max) ==  "2147483647")
+  assert(string.format("%d", min) == "-2147483648")
+  assert(string.format("%u", 0xffffffff) == "4294967295")
+  assert(string.format("%o", 0xABCD) == "125715")
+
+  max, min = 0x7fffffffffffffff, -0x8000000000000000
+  if max > 2.0^53 then  -- only for 64 bits
+    assert(string.format("%x", (2^52 | 0) - 1) == "fffffffffffff")
+    assert(string.format("0x%8X", 0x8f000003) == "0x8F000003")
+    assert(string.format("%d", 2^53) == "9007199254740992")
+    assert(string.format("%i", -2^53) == "-9007199254740992")
+    assert(string.format("%x", max) == "7fffffffffffffff")
+    assert(string.format("%x", min) == "8000000000000000")
+    assert(string.format("%d", max) ==  "9223372036854775807")
+    assert(string.format("%d", min) == "-9223372036854775808")
+    assert(string.format("%u", ~(-1 << 64)) == "18446744073709551615")
+    assert(tostring(1234567890123) == '1234567890123')
+  end
+end
+
+
+do print("testing 'format %a %A'")
+  local function matchhexa (n)
+    local s = string.format("%a", n)
+    -- result matches ISO C requirements
+    assert(string.find(s, "^%-?0x[1-9a-f]%.?[0-9a-f]*p[-+]?%d+$"))
+    assert(tonumber(s) == n)  -- and has full precision
+    s = string.format("%A", n)
+    assert(string.find(s, "^%-?0X[1-9A-F]%.?[0-9A-F]*P[-+]?%d+$"))
+    assert(tonumber(s) == n)
+  end
+  for _, n in ipairs{0.1, -0.1, 1/3, -1/3, 1e30, -1e30,
+                     -45/247, 1, -1, 2, -2, 3e-20, -3e-20} do
+    matchhexa(n)
+  end
+
+  assert(string.find(string.format("%A", 0.0), "^0X0%.?0*P%+?0$"))
+  assert(string.find(string.format("%a", -0.0), "^%-0x0%.?0*p%+?0$"))
+
+  if not _port then   -- test inf, -inf, NaN, and -0.0
+    assert(string.find(string.format("%a", 1/0), "^inf"))
+    assert(string.find(string.format("%A", -1/0), "^%-INF"))
+    assert(string.find(string.format("%a", 0/0), "^%-?nan"))
+    assert(string.find(string.format("%a", -0.0), "^%-0x0"))
+  end
+  
+  if not pcall(string.format, "%.3a", 0) then
+    (Message or print)("\n >>> modifiers for format '%a' not available <<<\n")
+  else
+    assert(string.find(string.format("%+.2A", 12), "^%+0X%x%.%x0P%+?%d$"))
+    assert(string.find(string.format("%.4A", -12), "^%-0X%x%.%x000P%+?%d$"))
+  end
+end
+
+
+-- errors in format
+
+local function check (fmt, msg)
+  checkerror(msg, string.format, fmt, 10)
+end
+
+local aux = string.rep('0', 600)
+check("%100.3d", "too long")
+check("%1"..aux..".3d", "too long")
+check("%1.100d", "too long")
+check("%10.1"..aux.."004d", "too long")
+check("%t", "invalid conversion")
+check("%"..aux.."d", "repeated flags")
+check("%d %d", "no value")
+
+
+assert(load("return 1\n--comment without ending EOL")() == 1)
+
+
+checkerror("table expected", table.concat, 3)
+assert(table.concat{} == "")
+assert(table.concat({}, 'x') == "")
+assert(table.concat({'\0', '\0\1', '\0\1\2'}, '.\0.') == "\0.\0.\0\1.\0.\0\1\2")
+local a = {}; for i=1,300 do a[i] = "xuxu" end
+assert(table.concat(a, "123").."123" == string.rep("xuxu123", 300))
+assert(table.concat(a, "b", 20, 20) == "xuxu")
+assert(table.concat(a, "", 20, 21) == "xuxuxuxu")
+assert(table.concat(a, "x", 22, 21) == "")
+assert(table.concat(a, "3", 299) == "xuxu3xuxu")
+assert(table.concat({}, "x", maxi, maxi - 1) == "")
+assert(table.concat({}, "x", mini + 1, mini) == "")
+assert(table.concat({}, "x", maxi, mini) == "")
+assert(table.concat({[maxi] = "alo"}, "x", maxi, maxi) == "alo")
+assert(table.concat({[maxi] = "alo", [maxi - 1] = "y"}, "-", maxi - 1, maxi)
+       == "y-alo")
+
+assert(not pcall(table.concat, {"a", "b", {}}))
+
+a = {"a","b","c"}
+assert(table.concat(a, ",", 1, 0) == "")
+assert(table.concat(a, ",", 1, 1) == "a")
+assert(table.concat(a, ",", 1, 2) == "a,b")
+assert(table.concat(a, ",", 2) == "b,c")
+assert(table.concat(a, ",", 3) == "c")
+assert(table.concat(a, ",", 4) == "")
+
+if not _port then
+
+  local locales = { "ptb", "pt_BR.iso88591", "ISO-8859-1" }
+  local function trylocale (w)
+    for i = 1, #locales do
+      if os.setlocale(locales[i], w) then
+        print(string.format("'%s' locale set to '%s'", w, locales[i]))
+        return locales[i]
+      end
+    end
+    print(string.format("'%s' locale not found", w))
+    return false
+  end
+
+  if trylocale("collate")  then
+    assert("alo" < "álo" and "álo" < "amo")
+  end
+
+  if trylocale("ctype") then
+    assert(string.gsub("áéíóú", "%a", "x") == "xxxxx")
+    assert(string.gsub("áÁéÉ", "%l", "x") == "xÁxÉ")
+    assert(string.gsub("áÁéÉ", "%u", "x") == "áxéx")
+    assert(string.upper"áÁé{xuxu}ção" == "ÁÁÉ{XUXU}ÇÃO")
+  end
+
+  os.setlocale("C")
+  assert(os.setlocale() == 'C')
+  assert(os.setlocale(nil, "numeric") == 'C')
+
+end
+
+
+-- bug in Lua 5.3.2
+-- 'gmatch' iterator does not work across coroutines
+do
+  local f = string.gmatch("1 2 3 4 5", "%d+")
+  assert(f() == "1")
+  co = coroutine.wrap(f)
+  assert(co() == "2")
+end
+
+
+if T==nil then
+  (Message or print)
+     ("\n >>> testC not active: skipping 'pushfstring' tests <<<\n")
+else
+
+  print"testing 'pushfstring'"
+
+  -- formats %U, %f, %I already tested elsewhere
+
+  local blen = 400    -- internal buffer length in 'luaO_pushfstring'
+
+  local function callpfs (op, fmt, n)
+    local x = {T.testC("pushfstring" .. op .. "; return *", fmt, n)}
+    -- stack has code, 'fmt', 'n', and result from operation
+    assert(#x == 4)  -- make sure nothing else was left in the stack
+    return x[4]
+  end
+
+  local function testpfs (op, fmt, n)
+    assert(callpfs(op, fmt, n) == string.format(fmt, n))
+  end
+
+  testpfs("I", "", 0)
+  testpfs("I", string.rep("a", blen - 1), 0)
+  testpfs("I", string.rep("a", blen), 0)
+  testpfs("I", string.rep("a", blen + 1), 0)
+
+  local str = string.rep("ab", blen) .. "%d" .. string.rep("d", blen / 2)
+  testpfs("I", str, 2^14)
+  testpfs("I", str, -2^15)
+
+  str = "%d" .. string.rep("cd", blen)
+  testpfs("I", str, 2^14)
+  testpfs("I", str, -2^15)
+
+  str = string.rep("c", blen - 2) .. "%d"
+  testpfs("I", str, 2^14)
+  testpfs("I", str, -2^15)
+
+  for l = 12, 14 do
+    local str1 = string.rep("a", l)
+    for i = 0, 500, 13 do
+      for j = 0, 500, 13 do
+        str = string.rep("a", i) .. "%s" .. string.rep("d", j)
+        testpfs("S", str, str1)
+        testpfs("S", str, str)
+      end
+    end
+  end
+
+  str = "abc %c def"
+  testpfs("I", str, string.byte("A"))
+  testpfs("I", str, 255)
+
+  str = string.rep("a", blen - 1) .. "%p" .. string.rep("cd", blen)
+  testpfs("P", str, {})
+
+  str = string.rep("%%", 3 * blen) .. "%p" .. string.rep("%%", 2 * blen)
+  testpfs("P", str, {})
+end
+
+
+print('OK')
+
diff --git a/test/external/lua-5.4.0-tests/tpack.lua b/test/external/lua-5.4.0-tests/tpack.lua
new file mode 100644
index 0000000..2b9953f
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/tpack.lua
@@ -0,0 +1,322 @@
+-- $Id: testes/tpack.lua $
+-- See Copyright Notice in file all.lua
+
+local pack = string.pack
+local packsize = string.packsize
+local unpack = string.unpack
+
+print "testing pack/unpack"
+
+-- maximum size for integers
+local NB = 16
+
+local sizeshort = packsize("h")
+local sizeint = packsize("i")
+local sizelong = packsize("l")
+local sizesize_t = packsize("T")
+local sizeLI = packsize("j")
+local sizefloat = packsize("f")
+local sizedouble = packsize("d")
+local sizenumber = packsize("n")
+local little = (pack("i2", 1) == "\1\0")
+local align = packsize("!xXi16")
+
+assert(1 <= sizeshort and sizeshort <= sizeint and sizeint <= sizelong and
+       sizefloat <= sizedouble)
+
+print("platform:")
+print(string.format(
+  "\tshort %d, int %d, long %d, size_t %d, float %d, double %d,\n\z
+   \tlua Integer %d, lua Number %d",
+   sizeshort, sizeint, sizelong, sizesize_t, sizefloat, sizedouble,
+   sizeLI, sizenumber))
+print("\t" .. (little and "little" or "big") .. " endian")
+print("\talignment: " .. align)
+
+
+-- check errors in arguments
+function checkerror (msg, f, ...)
+  local status, err = pcall(f, ...)
+  -- print(status, err, msg)
+  assert(not status and string.find(err, msg))
+end
+
+-- minimum behavior for integer formats
+assert(unpack("B", pack("B", 0xff)) == 0xff)
+assert(unpack("b", pack("b", 0x7f)) == 0x7f)
+assert(unpack("b", pack("b", -0x80)) == -0x80)
+
+assert(unpack("H", pack("H", 0xffff)) == 0xffff)
+assert(unpack("h", pack("h", 0x7fff)) == 0x7fff)
+assert(unpack("h", pack("h", -0x8000)) == -0x8000)
+
+assert(unpack("L", pack("L", 0xffffffff)) == 0xffffffff)
+assert(unpack("l", pack("l", 0x7fffffff)) == 0x7fffffff)
+assert(unpack("l", pack("l", -0x80000000)) == -0x80000000)
+
+
+for i = 1, NB do
+  -- small numbers with signal extension ("\xFF...")
+  local s = string.rep("\xff", i)
+  assert(pack("i" .. i, -1) == s)
+  assert(packsize("i" .. i) == #s)
+  assert(unpack("i" .. i, s) == -1)
+
+  -- small unsigned number ("\0...\xAA")
+  s = "\xAA" .. string.rep("\0", i - 1)
+  assert(pack("<I" .. i, 0xAA) == s)
+  assert(unpack("<I" .. i, s) == 0xAA)
+  assert(pack(">I" .. i, 0xAA) == s:reverse())
+  assert(unpack(">I" .. i, s:reverse()) == 0xAA)
+end
+
+do
+  local lnum = 0x13121110090807060504030201
+  local s = pack("<j", lnum)
+  assert(unpack("<j", s) == lnum)
+  assert(unpack("<i" .. sizeLI + 1, s .. "\0") == lnum)
+  assert(unpack("<i" .. sizeLI + 1, s .. "\0") == lnum)
+
+  for i = sizeLI + 1, NB do
+    local s = pack("<j", -lnum)
+    assert(unpack("<j", s) == -lnum)
+    -- strings with (correct) extra bytes
+    assert(unpack("<i" .. i, s .. ("\xFF"):rep(i - sizeLI)) == -lnum)
+    assert(unpack(">i" .. i, ("\xFF"):rep(i - sizeLI) .. s:reverse()) == -lnum)
+    assert(unpack("<I" .. i, s .. ("\0"):rep(i - sizeLI)) == -lnum)
+
+    -- overflows
+    checkerror("does not fit", unpack, "<I" .. i, ("\x00"):rep(i - 1) .. "\1")
+    checkerror("does not fit", unpack, ">i" .. i, "\1" .. ("\x00"):rep(i - 1))
+  end
+end
+
+for i = 1, sizeLI do
+  local lstr = "\1\2\3\4\5\6\7\8\9\10\11\12\13"
+  local lnum = 0x13121110090807060504030201
+  local n = lnum & (~(-1 << (i * 8)))
+  local s = string.sub(lstr, 1, i)
+  assert(pack("<i" .. i, n) == s)
+  assert(pack(">i" .. i, n) == s:reverse())
+  assert(unpack(">i" .. i, s:reverse()) == n)
+end
+
+-- sign extension
+do
+  local u = 0xf0
+  for i = 1, sizeLI - 1 do
+    assert(unpack("<i"..i, "\xf0"..("\xff"):rep(i - 1)) == -16)
+    assert(unpack(">I"..i, "\xf0"..("\xff"):rep(i - 1)) == u)
+    u = u * 256 + 0xff
+  end
+end
+
+-- mixed endianness
+do
+  assert(pack(">i2 <i2", 10, 20) == "\0\10\20\0")
+  local a, b = unpack("<i2 >i2", "\10\0\0\20")
+  assert(a == 10 and b == 20)
+  assert(pack("=i4", 2001) == pack("i4", 2001))
+end
+
+print("testing invalid formats")
+
+checkerror("out of limits", pack, "i0", 0)
+checkerror("out of limits", pack, "i" .. NB + 1, 0)
+checkerror("out of limits", pack, "!" .. NB + 1, 0)
+checkerror("%(17%) out of limits %[1,16%]", pack, "Xi" .. NB + 1)
+checkerror("invalid format option 'r'", pack, "i3r", 0)
+checkerror("16%-byte integer", unpack, "i16", string.rep('\3', 16))
+checkerror("not power of 2", pack, "!4i3", 0);
+checkerror("missing size", pack, "c", "")
+checkerror("variable%-length format", packsize, "s")
+checkerror("variable%-length format", packsize, "z")
+
+-- overflow in option size  (error will be in digit after limit)
+checkerror("invalid format", packsize, "c1" .. string.rep("0", 40))
+
+if packsize("i") == 4 then
+  -- result would be 2^31  (2^3 repetitions of 2^28 strings)
+  local s = string.rep("c268435456", 2^3)
+  checkerror("too large", packsize, s)
+  -- one less is OK
+  s = string.rep("c268435456", 2^3 - 1) .. "c268435455"
+  assert(packsize(s) == 0x7fffffff)
+end
+
+-- overflow in packing
+for i = 1, sizeLI - 1 do
+  local umax = (1 << (i * 8)) - 1
+  local max = umax >> 1
+  local min = ~max
+  checkerror("overflow", pack, "<I" .. i, -1)
+  checkerror("overflow", pack, "<I" .. i, min)
+  checkerror("overflow", pack, ">I" .. i, umax + 1)
+
+  checkerror("overflow", pack, ">i" .. i, umax)
+  checkerror("overflow", pack, ">i" .. i, max + 1)
+  checkerror("overflow", pack, "<i" .. i, min - 1)
+
+  assert(unpack(">i" .. i, pack(">i" .. i, max)) == max)
+  assert(unpack("<i" .. i, pack("<i" .. i, min)) == min)
+  assert(unpack(">I" .. i, pack(">I" .. i, umax)) == umax)
+end
+
+-- Lua integer size
+assert(unpack(">j", pack(">j", math.maxinteger)) == math.maxinteger)
+assert(unpack("<j", pack("<j", math.mininteger)) == math.mininteger)
+assert(unpack("<J", pack("<j", -1)) == -1)   -- maximum unsigned integer
+
+if little then
+  assert(pack("f", 24) == pack("<f", 24))
+else
+  assert(pack("f", 24) == pack(">f", 24))
+end
+
+print "testing pack/unpack of floating-point numbers" 
+
+for _, n in ipairs{0, -1.1, 1.9, 1/0, -1/0, 1e20, -1e20, 0.1, 2000.7} do
+    assert(unpack("n", pack("n", n)) == n)
+    assert(unpack("<n", pack("<n", n)) == n)
+    assert(unpack(">n", pack(">n", n)) == n)
+    assert(pack("<f", n) == pack(">f", n):reverse())
+    assert(pack(">d", n) == pack("<d", n):reverse())
+end
+
+-- for non-native precisions, test only with "round" numbers
+for _, n in ipairs{0, -1.5, 1/0, -1/0, 1e10, -1e9, 0.5, 2000.25} do
+  assert(unpack("<f", pack("<f", n)) == n)
+  assert(unpack(">f", pack(">f", n)) == n)
+  assert(unpack("<d", pack("<d", n)) == n)
+  assert(unpack(">d", pack(">d", n)) == n)
+end
+
+print "testing pack/unpack of strings"
+do
+  local s = string.rep("abc", 1000)
+  assert(pack("zB", s, 247) == s .. "\0\xF7")
+  local s1, b = unpack("zB", s .. "\0\xF9")
+  assert(b == 249 and s1 == s)
+  s1 = pack("s", s)
+  assert(unpack("s", s1) == s)
+
+  checkerror("does not fit", pack, "s1", s)
+
+  checkerror("contains zeros", pack, "z", "alo\0");
+
+  checkerror("unfinished string", unpack, "zc10000000", "alo")
+
+  for i = 2, NB do
+    local s1 = pack("s" .. i, s)
+    assert(unpack("s" .. i, s1) == s and #s1 == #s + i)
+  end
+end
+
+do
+  local x = pack("s", "alo")
+  checkerror("too short", unpack, "s", x:sub(1, -2))
+  checkerror("too short", unpack, "c5", "abcd")
+  checkerror("out of limits", pack, "s100", "alo")
+end
+
+do
+  assert(pack("c0", "") == "")
+  assert(packsize("c0") == 0)
+  assert(unpack("c0", "") == "")
+  assert(pack("<! c3", "abc") == "abc")
+  assert(packsize("<! c3") == 3)
+  assert(pack(">!4 c6", "abcdef") == "abcdef")
+  assert(pack("c3", "123") == "123")
+  assert(pack("c0", "") == "")
+  assert(pack("c8", "123456") == "123456\0\0")
+  assert(pack("c88", "") == string.rep("\0", 88))
+  assert(pack("c188", "ab") == "ab" .. string.rep("\0", 188 - 2))
+  local a, b, c = unpack("!4 z c3", "abcdefghi\0xyz")
+  assert(a == "abcdefghi" and b == "xyz" and c == 14)
+  checkerror("longer than", pack, "c3", "1234")
+end
+
+
+-- testing multiple types and sequence
+do
+  local x = pack("<b h b f d f n i", 1, 2, 3, 4, 5, 6, 7, 8)
+  assert(#x == packsize("<b h b f d f n i"))
+  local a, b, c, d, e, f, g, h = unpack("<b h b f d f n i", x)
+  assert(a == 1 and b == 2 and c == 3 and d == 4 and e == 5 and f == 6 and
+         g == 7 and h == 8) 
+end
+
+print "testing alignment"
+do
+  assert(pack(" < i1 i2 ", 2, 3) == "\2\3\0")   -- no alignment by default
+  local x = pack(">!8 b Xh i4 i8 c1 Xi8", -12, 100, 200, "\xEC")
+  assert(#x == packsize(">!8 b Xh i4 i8 c1 Xi8"))
+  assert(x == "\xf4" .. "\0\0\0" ..
+              "\0\0\0\100" ..
+              "\0\0\0\0\0\0\0\xC8" .. 
+              "\xEC" .. "\0\0\0\0\0\0\0")
+  local a, b, c, d, pos = unpack(">!8 c1 Xh i4 i8 b Xi8 XI XH", x)
+  assert(a == "\xF4" and b == 100 and c == 200 and d == -20 and (pos - 1) == #x)
+
+  x = pack(">!4 c3 c4 c2 z i4 c5 c2 Xi4",
+                  "abc", "abcd", "xz", "hello", 5, "world", "xy")
+  assert(x == "abcabcdxzhello\0\0\0\0\0\5worldxy\0")
+  local a, b, c, d, e, f, g, pos = unpack(">!4 c3 c4 c2 z i4 c5 c2 Xh Xi4", x)
+  assert(a == "abc" and b == "abcd" and c == "xz" and d == "hello" and
+         e == 5 and f == "world" and g == "xy" and (pos - 1) % 4 == 0)
+
+  x = pack(" b b Xd b Xb x", 1, 2, 3)
+  assert(packsize(" b b Xd b Xb x") == 4)
+  assert(x == "\1\2\3\0")
+  a, b, c, pos = unpack("bbXdb", x)
+  assert(a == 1 and b == 2 and c == 3 and pos == #x)
+
+  -- only alignment
+  assert(packsize("!8 xXi8") == 8)
+  local pos = unpack("!8 xXi8", "0123456701234567"); assert(pos == 9)
+  assert(packsize("!8 xXi2") == 2)
+  local pos = unpack("!8 xXi2", "0123456701234567"); assert(pos == 3)
+  assert(packsize("!2 xXi2") == 2)
+  local pos = unpack("!2 xXi2", "0123456701234567"); assert(pos == 3)
+  assert(packsize("!2 xXi8") == 2)
+  local pos = unpack("!2 xXi8", "0123456701234567"); assert(pos == 3)
+  assert(packsize("!16 xXi16") == 16)
+  local pos = unpack("!16 xXi16", "0123456701234567"); assert(pos == 17)
+
+  checkerror("invalid next option", pack, "X")
+  checkerror("invalid next option", unpack, "XXi", "")
+  checkerror("invalid next option", unpack, "X i", "")
+  checkerror("invalid next option", pack, "Xc1")
+end
+
+do    -- testing initial position
+  local x = pack("i4i4i4i4", 1, 2, 3, 4)
+  for pos = 1, 16, 4 do
+    local i, p = unpack("i4", x, pos)
+    assert(i == pos//4 + 1 and p == pos + 4)
+  end
+
+  -- with alignment
+  for pos = 0, 12 do    -- will always round position to power of 2
+    local i, p = unpack("!4 i4", x, pos + 1)
+    assert(i == (pos + 3)//4 + 1 and p == i*4 + 1)
+  end
+
+  -- negative indices
+  local i, p = unpack("!4 i4", x, -4)
+  assert(i == 4 and p == 17)
+  local i, p = unpack("!4 i4", x, -7)
+  assert(i == 4 and p == 17)
+  local i, p = unpack("!4 i4", x, -#x)
+  assert(i == 1 and p == 5)
+
+  -- limits
+  for i = 1, #x + 1 do
+    assert(unpack("c0", x, i) == "")
+  end
+  checkerror("out of string", unpack, "c0", x, #x + 2)
+ 
+end
+
+print "OK"
+
diff --git a/test/external/lua-5.4.0-tests/utf8.lua b/test/external/lua-5.4.0-tests/utf8.lua
new file mode 100644
index 0000000..6010d1a
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/utf8.lua
@@ -0,0 +1,241 @@
+-- $Id: testes/utf8.lua $
+-- See Copyright Notice in file all.lua
+
+print "testing UTF-8 library"
+
+local utf8 = require'utf8'
+
+
+local function checkerror (msg, f, ...)
+  local s, err = pcall(f, ...)
+  assert(not s and string.find(err, msg))
+end
+
+
+local function len (s)
+  return #string.gsub(s, "[\x80-\xBF]", "")
+end
+
+
+local justone = "^" .. utf8.charpattern .. "$"
+
+-- 't' is the list of codepoints of 's'
+local function checksyntax (s, t)
+  -- creates a string "return '\u{t[1]}...\u{t[n]}'"
+  local ts = {"return '"}
+  for i = 1, #t do ts[i + 1] = string.format("\\u{%x}", t[i]) end
+  ts[#t + 2] = "'"
+  ts = table.concat(ts)
+  -- its execution should result in 's'
+  assert(assert(load(ts))() == s)
+end
+
+assert(not utf8.offset("alo", 5))
+assert(not utf8.offset("alo", -4))
+
+-- 'check' makes several tests over the validity of string 's'.
+-- 't' is the list of codepoints of 's'.
+local function check (s, t, nonstrict)
+  local l = utf8.len(s, 1, -1, nonstrict)
+  assert(#t == l and len(s) == l)
+  assert(utf8.char(table.unpack(t)) == s)   -- 't' and 's' are equivalent
+
+  assert(utf8.offset(s, 0) == 1)
+
+  checksyntax(s, t)
+
+  -- creates new table with all codepoints of 's'
+  local t1 = {utf8.codepoint(s, 1, -1, nonstrict)}
+  assert(#t == #t1)
+  for i = 1, #t do assert(t[i] == t1[i]) end   -- 't' is equal to 't1'
+
+  for i = 1, l do   -- for all codepoints
+    local pi = utf8.offset(s, i)        -- position of i-th char
+    local pi1 = utf8.offset(s, 2, pi)   -- position of next char
+    assert(string.find(string.sub(s, pi, pi1 - 1), justone))
+    assert(utf8.offset(s, -1, pi1) == pi)
+    assert(utf8.offset(s, i - l - 1) == pi)
+    assert(pi1 - pi == #utf8.char(utf8.codepoint(s, pi, pi, nonstrict)))
+    for j = pi, pi1 - 1 do
+      assert(utf8.offset(s, 0, j) == pi)
+    end
+    for j = pi + 1, pi1 - 1 do
+      assert(not utf8.len(s, j))
+    end
+   assert(utf8.len(s, pi, pi, nonstrict) == 1)
+   assert(utf8.len(s, pi, pi1 - 1, nonstrict) == 1)
+   assert(utf8.len(s, pi, -1, nonstrict) == l - i + 1)
+   assert(utf8.len(s, pi1, -1, nonstrict) == l - i)
+   assert(utf8.len(s, 1, pi, nonstrict) == i)
+  end
+
+  local i = 0
+  for p, c in utf8.codes(s, nonstrict) do
+    i = i + 1
+    assert(c == t[i] and p == utf8.offset(s, i))
+    assert(utf8.codepoint(s, p, p, nonstrict) == c)
+  end
+  assert(i == #t)
+
+  i = 0
+  for c in string.gmatch(s, utf8.charpattern) do
+    i = i + 1
+    assert(c == utf8.char(t[i]))
+  end
+  assert(i == #t)
+
+  for i = 1, l do
+    assert(utf8.offset(s, i) == utf8.offset(s, i - l - 1, #s + 1))
+  end
+
+end
+
+
+do    -- error indication in utf8.len
+  local function check (s, p)
+    local a, b = utf8.len(s)
+    assert(not a and b == p)
+  end
+  check("abc\xE3def", 4)
+  check("汉字\x80", #("汉字") + 1)
+  check("\xF4\x9F\xBF", 1)
+  check("\xF4\x9F\xBF\xBF", 1)
+end
+
+-- errors in utf8.codes
+do
+  local function errorcodes (s)
+    checkerror("invalid UTF%-8 code",
+      function ()
+        for c in utf8.codes(s) do assert(c) end
+      end)
+  end
+  errorcodes("ab\xff")
+  errorcodes("\u{110000}")
+end
+
+-- error in initial position for offset
+checkerror("position out of bounds", utf8.offset, "abc", 1, 5)
+checkerror("position out of bounds", utf8.offset, "abc", 1, -4)
+checkerror("position out of bounds", utf8.offset, "", 1, 2)
+checkerror("position out of bounds", utf8.offset, "", 1, -1)
+checkerror("continuation byte", utf8.offset, "𦧺", 1, 2)
+checkerror("continuation byte", utf8.offset, "𦧺", 1, 2)
+checkerror("continuation byte", utf8.offset, "\x80", 1)
+
+-- error in indices for len
+checkerror("out of bounds", utf8.len, "abc", 0, 2)
+checkerror("out of bounds", utf8.len, "abc", 1, 4)
+
+
+local s = "hello World"
+local t = {string.byte(s, 1, -1)}
+for i = 1, utf8.len(s) do assert(t[i] == string.byte(s, i)) end
+check(s, t)
+
+check("汉字/漢字", {27721, 23383, 47, 28450, 23383,})
+
+do
+  local s = "áéí\128"
+  local t = {utf8.codepoint(s,1,#s - 1)}
+  assert(#t == 3 and t[1] == 225 and t[2] == 233 and t[3] == 237)
+  checkerror("invalid UTF%-8 code", utf8.codepoint, s, 1, #s)
+  checkerror("out of bounds", utf8.codepoint, s, #s + 1)
+  t = {utf8.codepoint(s, 4, 3)}
+  assert(#t == 0)
+  checkerror("out of bounds", utf8.codepoint, s, -(#s + 1), 1)
+  checkerror("out of bounds", utf8.codepoint, s, 1, #s + 1)
+  -- surrogates
+  assert(utf8.codepoint("\u{D7FF}") == 0xD800 - 1)
+  assert(utf8.codepoint("\u{E000}") == 0xDFFF + 1)
+  assert(utf8.codepoint("\u{D800}", 1, 1, true) == 0xD800)
+  assert(utf8.codepoint("\u{DFFF}", 1, 1, true) == 0xDFFF)
+  assert(utf8.codepoint("\u{7FFFFFFF}", 1, 1, true) == 0x7FFFFFFF)
+end
+
+assert(utf8.char() == "")
+assert(utf8.char(0, 97, 98, 99, 1) == "\0abc\1")
+
+assert(utf8.codepoint(utf8.char(0x10FFFF)) == 0x10FFFF)
+assert(utf8.codepoint(utf8.char(0x7FFFFFFF), 1, 1, true) == (1<<31) - 1)
+
+checkerror("value out of range", utf8.char, 0x7FFFFFFF + 1)
+checkerror("value out of range", utf8.char, -1)
+
+local function invalid (s)
+  checkerror("invalid UTF%-8 code", utf8.codepoint, s)
+  assert(not utf8.len(s))
+end
+
+-- UTF-8 representation for 0x11ffff (value out of valid range)
+invalid("\xF4\x9F\xBF\xBF")
+
+-- surrogates
+invalid("\u{D800}")
+invalid("\u{DFFF}")
+
+-- overlong sequences
+invalid("\xC0\x80")          -- zero
+invalid("\xC1\xBF")          -- 0x7F (should be coded in 1 byte)
+invalid("\xE0\x9F\xBF")      -- 0x7FF (should be coded in 2 bytes)
+invalid("\xF0\x8F\xBF\xBF")  -- 0xFFFF (should be coded in 3 bytes)
+
+
+-- invalid bytes
+invalid("\x80")  -- continuation byte
+invalid("\xBF")  -- continuation byte
+invalid("\xFE")  -- invalid byte
+invalid("\xFF")  -- invalid byte
+
+
+-- empty string
+check("", {})
+
+-- minimum and maximum values for each sequence size
+s = "\0 \x7F\z
+     \xC2\x80 \xDF\xBF\z
+     \xE0\xA0\x80 \xEF\xBF\xBF\z
+     \xF0\x90\x80\x80  \xF4\x8F\xBF\xBF"
+s = string.gsub(s, " ", "")
+check(s, {0,0x7F, 0x80,0x7FF, 0x800,0xFFFF, 0x10000,0x10FFFF})
+
+do
+  -- original UTF-8 values
+  local s = "\u{4000000}\u{7FFFFFFF}"
+  assert(#s == 12)
+  check(s, {0x4000000, 0x7FFFFFFF}, true)
+
+  s = "\u{200000}\u{3FFFFFF}"
+  assert(#s == 10)
+  check(s, {0x200000, 0x3FFFFFF}, true)
+
+  s = "\u{10000}\u{1fffff}"
+  assert(#s == 8)
+  check(s, {0x10000, 0x1FFFFF}, true)
+end
+
+x = "日本語a-4\0éó"
+check(x, {26085, 26412, 35486, 97, 45, 52, 0, 233, 243})
+
+
+-- Supplementary Characters
+check("𣲷𠜎𠱓�𠵼ab𠺢",
+      {0x23CB7, 0x2070E, 0x20C53, 0x2107B, 0x20D7C, 0x61, 0x62, 0x20EA2,})
+
+check("𨳊𩶘𦧺𨳒𥄫𤓓\xF4\x8F\xBF\xBF",
+      {0x28CCA, 0x29D98, 0x269FA, 0x28CD2, 0x2512B, 0x244D3, 0x10ffff})
+
+
+local i = 0
+for p, c in string.gmatch(x, "()(" .. utf8.charpattern .. ")") do
+  i = i + 1
+  assert(utf8.offset(x, i) == p)
+  assert(utf8.len(x, p) == utf8.len(x) - i + 1)
+  assert(utf8.len(c) == 1)
+  for j = 1, #c - 1 do
+    assert(utf8.offset(x, 0, p + j - 1) == p)
+  end
+end
+
+print'ok'
+
diff --git a/test/external/lua-5.4.0-tests/vararg.lua b/test/external/lua-5.4.0-tests/vararg.lua
new file mode 100644
index 0000000..44848d2
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/vararg.lua
@@ -0,0 +1,151 @@
+-- $Id: testes/vararg.lua $
+-- See Copyright Notice in file all.lua
+
+print('testing vararg')
+
+function f(a, ...)
+  local x = {n = select('#', ...), ...}
+  for i = 1, x.n do assert(a[i] == x[i]) end
+  return x.n
+end
+
+function c12 (...)
+  assert(arg == _G.arg)    -- no local 'arg'
+  local x = {...}; x.n = #x
+  local res = (x.n==2 and x[1] == 1 and x[2] == 2)
+  if res then res = 55 end
+  return res, 2
+end
+
+function vararg (...) return {n = select('#', ...), ...} end
+
+local call = function (f, args) return f(table.unpack(args, 1, args.n)) end
+
+assert(f() == 0)
+assert(f({1,2,3}, 1, 2, 3) == 3)
+assert(f({"alo", nil, 45, f, nil}, "alo", nil, 45, f, nil) == 5)
+
+assert(vararg().n == 0)
+assert(vararg(nil, nil).n == 2)
+
+assert(c12(1,2)==55)
+a,b = assert(call(c12, {1,2}))
+assert(a == 55 and b == 2)
+a = call(c12, {1,2;n=2})
+assert(a == 55 and b == 2)
+a = call(c12, {1,2;n=1})
+assert(not a)
+assert(c12(1,2,3) == false)
+local a = vararg(call(next, {_G,nil;n=2}))
+local b,c = next(_G)
+assert(a[1] == b and a[2] == c and a.n == 2)
+a = vararg(call(call, {c12, {1,2}}))
+assert(a.n == 2 and a[1] == 55 and a[2] == 2)
+a = call(print, {'+'})
+assert(a == nil)
+
+local t = {1, 10}
+function t:f (...) local arg = {...}; return self[...]+#arg end
+assert(t:f(1,4) == 3 and t:f(2) == 11)
+print('+')
+
+lim = 20
+local i, a = 1, {}
+while i <= lim do a[i] = i+0.3; i=i+1 end
+
+function f(a, b, c, d, ...)
+  local more = {...}
+  assert(a == 1.3 and more[1] == 5.3 and
+         more[lim-4] == lim+0.3 and not more[lim-3])
+end
+
+function g(a,b,c)
+  assert(a == 1.3 and b == 2.3 and c == 3.3)
+end
+
+call(f, a)
+call(g, a)
+
+a = {}
+i = 1
+while i <= lim do a[i] = i; i=i+1 end
+assert(call(math.max, a) == lim)
+
+print("+")
+
+
+-- new-style varargs
+
+function oneless (a, ...) return ... end
+
+function f (n, a, ...)
+  local b
+  assert(arg == _G.arg)   -- no local 'arg'
+  if n == 0 then
+    local b, c, d = ...
+    return a, b, c, d, oneless(oneless(oneless(...)))
+  else
+    n, b, a = n-1, ..., a
+    assert(b == ...)
+    return f(n, a, ...)
+  end
+end
+
+a,b,c,d,e = assert(f(10,5,4,3,2,1))
+assert(a==5 and b==4 and c==3 and d==2 and e==1)
+
+a,b,c,d,e = f(4)
+assert(a==nil and b==nil and c==nil and d==nil and e==nil)
+
+
+-- varargs for main chunks
+f = load[[ return {...} ]]
+x = f(2,3)
+assert(x[1] == 2 and x[2] == 3 and x[3] == undef)
+
+
+f = load[[
+  local x = {...}
+  for i=1,select('#', ...) do assert(x[i] == select(i, ...)) end
+  assert(x[select('#', ...)+1] == undef)
+  return true
+]]
+
+assert(f("a", "b", nil, {}, assert))
+assert(f())
+
+a = {select(3, table.unpack{10,20,30,40})}
+assert(#a == 2 and a[1] == 30 and a[2] == 40)
+a = {select(1)}
+assert(next(a) == nil)
+a = {select(-1, 3, 5, 7)}
+assert(a[1] == 7 and a[2] == undef)
+a = {select(-2, 3, 5, 7)}
+assert(a[1] == 5 and a[2] == 7 and a[3] == undef)
+pcall(select, 10000)
+pcall(select, -10000)
+
+
+-- bug in 5.2.2
+
+function f(p1, p2, p3, p4, p5, p6, p7, p8, p9, p10,
+p11, p12, p13, p14, p15, p16, p17, p18, p19, p20,
+p21, p22, p23, p24, p25, p26, p27, p28, p29, p30,
+p31, p32, p33, p34, p35, p36, p37, p38, p39, p40,
+p41, p42, p43, p44, p45, p46, p48, p49, p50, ...)
+  local a1,a2,a3,a4,a5,a6,a7
+  local a8,a9,a10,a11,a12,a13,a14
+end
+
+-- assertion fail here
+f()
+
+-- missing arguments in tail call
+do
+  local function f(a,b,c) return c, b end
+  local function g() return f(1,2) end
+  local a, b = g()
+  assert(a == nil and b == 2)
+end
+print('OK')
+
diff --git a/test/external/lua-5.4.0-tests/verybig.lua b/test/external/lua-5.4.0-tests/verybig.lua
new file mode 100644
index 0000000..8fb7b13
--- /dev/null
+++ b/test/external/lua-5.4.0-tests/verybig.lua
@@ -0,0 +1,152 @@
+-- $Id: testes/verybig.lua $
+-- See Copyright Notice in file all.lua
+
+print "testing RK"
+
+-- testing opcodes with RK arguments larger than K limit
+local function foo ()
+  local dummy = {
+     -- fill first 256 entries in table of constants
+     1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16,
+     17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32,
+     33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,
+     49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64,
+     65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80,
+     81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96,
+     97, 98, 99, 100, 101, 102, 103, 104,
+     105, 106, 107, 108, 109, 110, 111, 112,
+     113, 114, 115, 116, 117, 118, 119, 120,
+     121, 122, 123, 124, 125, 126, 127, 128,
+     129, 130, 131, 132, 133, 134, 135, 136,
+     137, 138, 139, 140, 141, 142, 143, 144,
+     145, 146, 147, 148, 149, 150, 151, 152,
+     153, 154, 155, 156, 157, 158, 159, 160,
+     161, 162, 163, 164, 165, 166, 167, 168,
+     169, 170, 171, 172, 173, 174, 175, 176,
+     177, 178, 179, 180, 181, 182, 183, 184,
+     185, 186, 187, 188, 189, 190, 191, 192,
+     193, 194, 195, 196, 197, 198, 199, 200,
+     201, 202, 203, 204, 205, 206, 207, 208,
+     209, 210, 211, 212, 213, 214, 215, 216,
+     217, 218, 219, 220, 221, 222, 223, 224,
+     225, 226, 227, 228, 229, 230, 231, 232,
+     233, 234, 235, 236, 237, 238, 239, 240,
+     241, 242, 243, 244, 245, 246, 247, 248,
+     249, 250, 251, 252, 253, 254, 255, 256,
+  }
+  assert(24.5 + 0.6 == 25.1)
+  local t = {foo = function (self, x) return x + self.x end, x = 10}
+  t.t = t
+  assert(t:foo(1.5) == 11.5)
+  assert(t.t:foo(0.5) == 10.5)   -- bug in 5.2 alpha
+  assert(24.3 == 24.3)
+  assert((function () return t.x end)() == 10)
+end
+
+
+foo()
+foo = nil
+
+if _soft then return 10 end
+
+print "testing large programs (>64k)"
+
+-- template to create a very big test file
+prog = [[$
+
+local a,b
+
+b = {$1$
+  b30009 = 65534,
+  b30010 = 65535,
+  b30011 = 65536,
+  b30012 = 65537,
+  b30013 = 16777214,
+  b30014 = 16777215,
+  b30015 = 16777216,
+  b30016 = 16777217,
+  b30017 = 0x7fffff,
+  b30018 = -0x7fffff,
+  b30019 = 0x1ffffff,
+  b30020 = -0x1ffffd,
+  b30021 = -65534,
+  b30022 = -65535,
+  b30023 = -65536,
+  b30024 = -0xffffff,
+  b30025 = 15012.5,
+  $2$
+};
+
+assert(b.a50008 == 25004 and b["a11"] == -5.5)
+assert(b.a33007 == -16503.5 and b.a50009 == -25004.5)
+assert(b["b"..30024] == -0xffffff)
+
+function b:xxx (a,b) return a+b end
+assert(b:xxx(10, 12) == 22)   -- pushself with non-constant index
+b["xxx"] = undef
+
+s = 0; n=0
+for a,b in pairs(b) do s=s+b; n=n+1 end
+-- with 32-bit floats, exact value of 's' depends on summation order
+assert(81800000.0 < s and s < 81860000 and n == 70001)
+
+a = nil; b = nil
+print'+'
+
+function f(x) b=x end
+
+a = f{$3$} or 10
+
+assert(a==10)
+assert(b[1] == "a10" and b[2] == 5 and b[#b-1] == "a50009")
+
+
+function xxxx (x) return b[x] end
+
+assert(xxxx(3) == "a11")
+
+a = nil; b=nil
+xxxx = nil
+
+return 10
+
+]]
+
+-- functions to fill in the $n$
+
+local function sig (x)
+  return (x % 2 == 0) and '' or '-'
+end
+
+F = {
+function ()   -- $1$
+  for i=10,50009 do
+    io.write('a', i, ' = ', sig(i), 5+((i-10)/2), ',\n')
+  end
+end,
+
+function ()   -- $2$
+  for i=30026,50009 do
+    io.write('b', i, ' = ', sig(i), 15013+((i-30026)/2), ',\n')
+  end
+end,
+
+function ()   -- $3$
+  for i=10,50009 do
+    io.write('"a', i, '", ', sig(i), 5+((i-10)/2), ',\n')
+  end
+end,
+}
+
+file = os.tmpname()
+io.output(file)
+for s in string.gmatch(prog, "$([^$]+)") do
+  local n = tonumber(s)
+  if not n then io.write(s) else F[n]() end
+end
+io.close()
+result = dofile(file)
+assert(os.remove(file))
+print'OK'
+return result
+
diff --git a/test/external/lua-5.4.0/Makefile b/test/external/lua-5.4.0/Makefile
new file mode 100644
index 0000000..416f444
--- /dev/null
+++ b/test/external/lua-5.4.0/Makefile
@@ -0,0 +1,106 @@
+# Makefile for installing Lua
+# See doc/readme.html for installation and customization instructions.
+
+# == CHANGE THE SETTINGS BELOW TO SUIT YOUR ENVIRONMENT =======================
+
+# Your platform. See PLATS for possible values.
+PLAT= guess
+
+# Where to install. The installation starts in the src and doc directories,
+# so take care if INSTALL_TOP is not an absolute path. See the local target.
+# You may want to make INSTALL_LMOD and INSTALL_CMOD consistent with
+# LUA_ROOT, LUA_LDIR, and LUA_CDIR in luaconf.h.
+INSTALL_TOP= /usr/local
+INSTALL_BIN= $(INSTALL_TOP)/bin
+INSTALL_INC= $(INSTALL_TOP)/include
+INSTALL_LIB= $(INSTALL_TOP)/lib
+INSTALL_MAN= $(INSTALL_TOP)/man/man1
+INSTALL_LMOD= $(INSTALL_TOP)/share/lua/$V
+INSTALL_CMOD= $(INSTALL_TOP)/lib/lua/$V
+
+# How to install. If your install program does not support "-p", then
+# you may have to run ranlib on the installed liblua.a.
+INSTALL= install -p
+INSTALL_EXEC= $(INSTALL) -m 0755
+INSTALL_DATA= $(INSTALL) -m 0644
+#
+# If you don't have "install" you can use "cp" instead.
+# INSTALL= cp -p
+# INSTALL_EXEC= $(INSTALL)
+# INSTALL_DATA= $(INSTALL)
+
+# Other utilities.
+MKDIR= mkdir -p
+RM= rm -f
+
+# == END OF USER SETTINGS -- NO NEED TO CHANGE ANYTHING BELOW THIS LINE =======
+
+# Convenience platforms targets.
+PLATS= guess aix bsd c89 freebsd generic linux linux-readline macosx mingw posix solaris
+
+# What to install.
+TO_BIN= lua luac
+TO_INC= lua.h luaconf.h lualib.h lauxlib.h lua.hpp
+TO_LIB= liblua.a
+TO_MAN= lua.1 luac.1
+
+# Lua version and release.
+V= 5.4
+R= $V.0
+
+# Targets start here.
+all:	$(PLAT)
+
+$(PLATS) help test clean:
+	@cd src && $(MAKE) $@
+
+install: dummy
+	cd src && $(MKDIR) $(INSTALL_BIN) $(INSTALL_INC) $(INSTALL_LIB) $(INSTALL_MAN) $(INSTALL_LMOD) $(INSTALL_CMOD)
+	cd src && $(INSTALL_EXEC) $(TO_BIN) $(INSTALL_BIN)
+	cd src && $(INSTALL_DATA) $(TO_INC) $(INSTALL_INC)
+	cd src && $(INSTALL_DATA) $(TO_LIB) $(INSTALL_LIB)
+	cd doc && $(INSTALL_DATA) $(TO_MAN) $(INSTALL_MAN)
+
+uninstall:
+	cd src && cd $(INSTALL_BIN) && $(RM) $(TO_BIN)
+	cd src && cd $(INSTALL_INC) && $(RM) $(TO_INC)
+	cd src && cd $(INSTALL_LIB) && $(RM) $(TO_LIB)
+	cd doc && cd $(INSTALL_MAN) && $(RM) $(TO_MAN)
+
+local:
+	$(MAKE) install INSTALL_TOP=../install
+
+# make may get confused with install/ if it does not support .PHONY.
+dummy:
+
+# Echo config parameters.
+echo:
+	@cd src && $(MAKE) -s echo
+	@echo "PLAT= $(PLAT)"
+	@echo "V= $V"
+	@echo "R= $R"
+	@echo "TO_BIN= $(TO_BIN)"
+	@echo "TO_INC= $(TO_INC)"
+	@echo "TO_LIB= $(TO_LIB)"
+	@echo "TO_MAN= $(TO_MAN)"
+	@echo "INSTALL_TOP= $(INSTALL_TOP)"
+	@echo "INSTALL_BIN= $(INSTALL_BIN)"
+	@echo "INSTALL_INC= $(INSTALL_INC)"
+	@echo "INSTALL_LIB= $(INSTALL_LIB)"
+	@echo "INSTALL_MAN= $(INSTALL_MAN)"
+	@echo "INSTALL_LMOD= $(INSTALL_LMOD)"
+	@echo "INSTALL_CMOD= $(INSTALL_CMOD)"
+	@echo "INSTALL_EXEC= $(INSTALL_EXEC)"
+	@echo "INSTALL_DATA= $(INSTALL_DATA)"
+
+# Echo pkg-config data.
+pc:
+	@echo "version=$R"
+	@echo "prefix=$(INSTALL_TOP)"
+	@echo "libdir=$(INSTALL_LIB)"
+	@echo "includedir=$(INSTALL_INC)"
+
+# Targets that do not create files (not all makes understand .PHONY).
+.PHONY: all $(PLATS) help test clean install uninstall local dummy echo pc
+
+# (end of Makefile)
diff --git a/test/external/lua-5.4.0/README b/test/external/lua-5.4.0/README
new file mode 100644
index 0000000..57572c0
--- /dev/null
+++ b/test/external/lua-5.4.0/README
@@ -0,0 +1,6 @@
+
+This is Lua 5.4.0, released on 18 Jun 2020.
+
+For installation instructions, license details, and
+further information about Lua, see doc/readme.html.
+
diff --git a/test/external/lua-5.4.0/doc/contents.html b/test/external/lua-5.4.0/doc/contents.html
new file mode 100644
index 0000000..ffc0323
--- /dev/null
+++ b/test/external/lua-5.4.0/doc/contents.html
@@ -0,0 +1,674 @@
+<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
+<HTML>
+<HEAD>
+<TITLE>Lua 5.4 Reference Manual - contents</TITLE>
+<LINK REL="stylesheet" TYPE="text/css" HREF="lua.css">
+<LINK REL="stylesheet" TYPE="text/css" HREF="index.css">
+<META HTTP-EQUIV="content-type" CONTENT="text/html; charset=iso-8859-1">
+</HEAD>
+
+<BODY>
+
+<H1>
+<A HREF="http://www.lua.org/"><IMG SRC="logo.gif" ALT="Lua"></A>
+Lua 5.4 Reference Manual
+</H1>
+
+<P>
+The reference manual is the official definition of the Lua language.
+<BR>
+For a complete introduction to Lua programming, see the book
+<A HREF="http://www.lua.org/pil/">Programming in Lua</A>.
+
+<DIV CLASS="menubar">
+<A HREF="manual.html">start</A>
+&middot;
+<A HREF="#contents">contents</A>
+&middot;
+<A HREF="#index">index</A>
+&middot;
+<A HREF="http://www.lua.org/manual/">other versions</A>
+</DIV>
+
+<P>
+<SMALL>
+Copyright &copy; 2020 Lua.org, PUC-Rio.
+Freely available under the terms of the
+<A HREF="http://www.lua.org/license.html">Lua license</A>.
+</SMALL>
+
+<H2><A NAME="contents">Contents</A></H2>
+<UL CLASS="contents menubar">
+<LI><A HREF="manual.html">1 &ndash; Introduction</A>
+<P>
+<LI><A HREF="manual.html#2">2 &ndash; Basic Concepts</A>
+<UL>
+<LI><A HREF="manual.html#2.1">2.1 &ndash; Values and Types</A>
+<LI><A HREF="manual.html#2.2">2.2 &ndash; Environments and the Global Environment</A>
+<LI><A HREF="manual.html#2.3">2.3 &ndash; Error Handling</A>
+<LI><A HREF="manual.html#2.4">2.4 &ndash; Metatables and Metamethods</A>
+<LI><A HREF="manual.html#2.5">2.5 &ndash; Garbage Collection</A>
+<UL>
+<LI><A HREF="manual.html#2.5.1">2.5.1 &ndash; Incremental Garbage Collection</A>
+<LI><A HREF="manual.html#2.5.2">2.5.2 &ndash; Generational Garbage Collection</A>
+<LI><A HREF="manual.html#2.5.3">2.5.3 &ndash; Garbage-Collection Metamethods</A>
+<LI><A HREF="manual.html#2.5.4">2.5.4 &ndash; Weak Tables</A>
+</UL>
+<LI><A HREF="manual.html#2.6">2.6 &ndash; Coroutines</A>
+</UL>
+<P>
+<LI><A HREF="manual.html#3">3 &ndash; The Language</A>
+<UL>
+<LI><A HREF="manual.html#3.1">3.1 &ndash; Lexical Conventions</A>
+<LI><A HREF="manual.html#3.2">3.2 &ndash; Variables</A>
+<LI><A HREF="manual.html#3.3">3.3 &ndash; Statements</A>
+<UL>
+<LI><A HREF="manual.html#3.3.1">3.3.1 &ndash; Blocks</A>
+<LI><A HREF="manual.html#3.3.2">3.3.2 &ndash; Chunks</A>
+<LI><A HREF="manual.html#3.3.3">3.3.3 &ndash; Assignment</A>
+<LI><A HREF="manual.html#3.3.4">3.3.4 &ndash; Control Structures</A>
+<LI><A HREF="manual.html#3.3.5">3.3.5 &ndash; For Statement</A>
+<LI><A HREF="manual.html#3.3.6">3.3.6 &ndash; Function Calls as Statements</A>
+<LI><A HREF="manual.html#3.3.7">3.3.7 &ndash; Local Declarations</A>
+<LI><A HREF="manual.html#3.3.8">3.3.8 &ndash; To-be-closed Variables</A>
+</UL>
+<LI><A HREF="manual.html#3.4">3.4 &ndash; Expressions</A>
+<UL>
+<LI><A HREF="manual.html#3.4.1">3.4.1 &ndash; Arithmetic Operators</A>
+<LI><A HREF="manual.html#3.4.2">3.4.2 &ndash; Bitwise Operators</A>
+<LI><A HREF="manual.html#3.4.3">3.4.3 &ndash; Coercions and Conversions</A>
+<LI><A HREF="manual.html#3.4.4">3.4.4 &ndash; Relational Operators</A>
+<LI><A HREF="manual.html#3.4.5">3.4.5 &ndash; Logical Operators</A>
+<LI><A HREF="manual.html#3.4.6">3.4.6 &ndash; Concatenation</A>
+<LI><A HREF="manual.html#3.4.7">3.4.7 &ndash; The Length Operator</A>
+<LI><A HREF="manual.html#3.4.8">3.4.8 &ndash; Precedence</A>
+<LI><A HREF="manual.html#3.4.9">3.4.9 &ndash; Table Constructors</A>
+<LI><A HREF="manual.html#3.4.10">3.4.10 &ndash; Function Calls</A>
+<LI><A HREF="manual.html#3.4.11">3.4.11 &ndash; Function Definitions</A>
+</UL>
+<LI><A HREF="manual.html#3.5">3.5 &ndash; Visibility Rules</A>
+</UL>
+<P>
+<LI><A HREF="manual.html#4">4 &ndash; The Application Program Interface</A>
+<UL>
+<LI><A HREF="manual.html#4.1">4.1 &ndash; The Stack</A>
+<UL>
+<LI><A HREF="manual.html#4.1.1">4.1.1 &ndash; Stack Size</A>
+<LI><A HREF="manual.html#4.1.2">4.1.2 &ndash; Valid and Acceptable Indices</A>
+</UL>
+<LI><A HREF="manual.html#4.2">4.2 &ndash; C Closures</A>
+<LI><A HREF="manual.html#4.3">4.3 &ndash; Registry</A>
+<LI><A HREF="manual.html#4.4">4.4 &ndash; Error Handling in C</A>
+<UL>
+<LI><A HREF="manual.html#4.4.1">4.4.1 &ndash; Status Codes</A>
+</UL>
+<LI><A HREF="manual.html#4.5">4.5 &ndash; Handling Yields in C</A>
+<LI><A HREF="manual.html#4.6">4.6 &ndash; Functions and Types</A>
+<LI><A HREF="manual.html#4.7">4.7 &ndash; The Debug Interface</A>
+</UL>
+<P>
+<LI><A HREF="manual.html#5">5 &ndash; The Auxiliary Library</A>
+<UL>
+<LI><A HREF="manual.html#5.1">5.1 &ndash; Functions and Types</A>
+</UL>
+<P>
+<LI><A HREF="manual.html#6">6 &ndash; The Standard Libraries</A>
+<UL>
+<LI><A HREF="manual.html#6.1">6.1 &ndash; Basic Functions</A>
+<LI><A HREF="manual.html#6.2">6.2 &ndash; Coroutine Manipulation</A>
+<LI><A HREF="manual.html#6.3">6.3 &ndash; Modules</A>
+<LI><A HREF="manual.html#6.4">6.4 &ndash; String Manipulation</A>
+<UL>
+<LI><A HREF="manual.html#6.4.1">6.4.1 &ndash; Patterns</A>
+<LI><A HREF="manual.html#6.4.2">6.4.2 &ndash; Format Strings for Pack and Unpack</A>
+</UL>
+<LI><A HREF="manual.html#6.5">6.5 &ndash; UTF-8 Support</A>
+<LI><A HREF="manual.html#6.6">6.6 &ndash; Table Manipulation</A>
+<LI><A HREF="manual.html#6.7">6.7 &ndash; Mathematical Functions</A>
+<LI><A HREF="manual.html#6.8">6.8 &ndash; Input and Output Facilities</A>
+<LI><A HREF="manual.html#6.9">6.9 &ndash; Operating System Facilities</A>
+<LI><A HREF="manual.html#6.10">6.10 &ndash; The Debug Library</A>
+</UL>
+<P>
+<LI><A HREF="manual.html#7">7 &ndash; Lua Standalone</A>
+<P>
+<LI><A HREF="manual.html#8">8 &ndash; Incompatibilities with the Previous Version</A>
+<UL>
+<LI><A HREF="manual.html#8.1">8.1 &ndash; Incompatibilities in the Language</A>
+<LI><A HREF="manual.html#8.2">8.2 &ndash; Incompatibilities in the Libraries</A>
+<LI><A HREF="manual.html#8.3">8.3 &ndash; Incompatibilities in the API</A>
+</UL>
+<P>
+<LI><A HREF="manual.html#9">9 &ndash; The Complete Syntax of Lua</A>
+</UL>
+
+<H2><A NAME="index">Index</A></H2>
+<TABLE CLASS="menubar" WIDTH="100%">
+<TR>
+<TD>
+<H3><A NAME="functions">Lua functions</A></H3>
+<P>
+<A HREF="manual.html#6.1">basic</A><BR>
+<A HREF="manual.html#pdf-_G">_G</A><BR>
+<A HREF="manual.html#pdf-_VERSION">_VERSION</A><BR>
+<A HREF="manual.html#pdf-assert">assert</A><BR>
+<A HREF="manual.html#pdf-collectgarbage">collectgarbage</A><BR>
+<A HREF="manual.html#pdf-dofile">dofile</A><BR>
+<A HREF="manual.html#pdf-error">error</A><BR>
+<A HREF="manual.html#pdf-getmetatable">getmetatable</A><BR>
+<A HREF="manual.html#pdf-ipairs">ipairs</A><BR>
+<A HREF="manual.html#pdf-load">load</A><BR>
+<A HREF="manual.html#pdf-loadfile">loadfile</A><BR>
+<A HREF="manual.html#pdf-next">next</A><BR>
+<A HREF="manual.html#pdf-pairs">pairs</A><BR>
+<A HREF="manual.html#pdf-pcall">pcall</A><BR>
+<A HREF="manual.html#pdf-print">print</A><BR>
+<A HREF="manual.html#pdf-rawequal">rawequal</A><BR>
+<A HREF="manual.html#pdf-rawget">rawget</A><BR>
+<A HREF="manual.html#pdf-rawlen">rawlen</A><BR>
+<A HREF="manual.html#pdf-rawset">rawset</A><BR>
+<A HREF="manual.html#pdf-require">require</A><BR>
+<A HREF="manual.html#pdf-select">select</A><BR>
+<A HREF="manual.html#pdf-setmetatable">setmetatable</A><BR>
+<A HREF="manual.html#pdf-tonumber">tonumber</A><BR>
+<A HREF="manual.html#pdf-tostring">tostring</A><BR>
+<A HREF="manual.html#pdf-type">type</A><BR>
+<A HREF="manual.html#pdf-warn">warn</A><BR>
+<A HREF="manual.html#pdf-xpcall">xpcall</A><BR>
+
+<P>
+<A HREF="manual.html#6.2">coroutine</A><BR>
+<A HREF="manual.html#pdf-coroutine.close">coroutine.close</A><BR>
+<A HREF="manual.html#pdf-coroutine.create">coroutine.create</A><BR>
+<A HREF="manual.html#pdf-coroutine.isyieldable">coroutine.isyieldable</A><BR>
+<A HREF="manual.html#pdf-coroutine.resume">coroutine.resume</A><BR>
+<A HREF="manual.html#pdf-coroutine.running">coroutine.running</A><BR>
+<A HREF="manual.html#pdf-coroutine.status">coroutine.status</A><BR>
+<A HREF="manual.html#pdf-coroutine.wrap">coroutine.wrap</A><BR>
+<A HREF="manual.html#pdf-coroutine.yield">coroutine.yield</A><BR>
+
+<P>
+<A HREF="manual.html#6.10">debug</A><BR>
+<A HREF="manual.html#pdf-debug.debug">debug.debug</A><BR>
+<A HREF="manual.html#pdf-debug.gethook">debug.gethook</A><BR>
+<A HREF="manual.html#pdf-debug.getinfo">debug.getinfo</A><BR>
+<A HREF="manual.html#pdf-debug.getlocal">debug.getlocal</A><BR>
+<A HREF="manual.html#pdf-debug.getmetatable">debug.getmetatable</A><BR>
+<A HREF="manual.html#pdf-debug.getregistry">debug.getregistry</A><BR>
+<A HREF="manual.html#pdf-debug.getupvalue">debug.getupvalue</A><BR>
+<A HREF="manual.html#pdf-debug.getuservalue">debug.getuservalue</A><BR>
+<A HREF="manual.html#pdf-debug.setcstacklimit">debug.setcstacklimit</A><BR>
+<A HREF="manual.html#pdf-debug.sethook">debug.sethook</A><BR>
+<A HREF="manual.html#pdf-debug.setlocal">debug.setlocal</A><BR>
+<A HREF="manual.html#pdf-debug.setmetatable">debug.setmetatable</A><BR>
+<A HREF="manual.html#pdf-debug.setupvalue">debug.setupvalue</A><BR>
+<A HREF="manual.html#pdf-debug.setuservalue">debug.setuservalue</A><BR>
+<A HREF="manual.html#pdf-debug.traceback">debug.traceback</A><BR>
+<A HREF="manual.html#pdf-debug.upvalueid">debug.upvalueid</A><BR>
+<A HREF="manual.html#pdf-debug.upvaluejoin">debug.upvaluejoin</A><BR>
+
+<P>
+<A HREF="manual.html#6.8">io</A><BR>
+<A HREF="manual.html#pdf-io.close">io.close</A><BR>
+<A HREF="manual.html#pdf-io.flush">io.flush</A><BR>
+<A HREF="manual.html#pdf-io.input">io.input</A><BR>
+<A HREF="manual.html#pdf-io.lines">io.lines</A><BR>
+<A HREF="manual.html#pdf-io.open">io.open</A><BR>
+<A HREF="manual.html#pdf-io.output">io.output</A><BR>
+<A HREF="manual.html#pdf-io.popen">io.popen</A><BR>
+<A HREF="manual.html#pdf-io.read">io.read</A><BR>
+<A HREF="manual.html#pdf-io.stderr">io.stderr</A><BR>
+<A HREF="manual.html#pdf-io.stdin">io.stdin</A><BR>
+<A HREF="manual.html#pdf-io.stdout">io.stdout</A><BR>
+<A HREF="manual.html#pdf-io.tmpfile">io.tmpfile</A><BR>
+<A HREF="manual.html#pdf-io.type">io.type</A><BR>
+<A HREF="manual.html#pdf-io.write">io.write</A><BR>
+
+<A HREF="manual.html#pdf-file:close">file:close</A><BR>
+<A HREF="manual.html#pdf-file:flush">file:flush</A><BR>
+<A HREF="manual.html#pdf-file:lines">file:lines</A><BR>
+<A HREF="manual.html#pdf-file:read">file:read</A><BR>
+<A HREF="manual.html#pdf-file:seek">file:seek</A><BR>
+<A HREF="manual.html#pdf-file:setvbuf">file:setvbuf</A><BR>
+<A HREF="manual.html#pdf-file:write">file:write</A><BR>
+
+</TD>
+<TD>
+<H3>&nbsp;</H3>
+<P>
+<A HREF="manual.html#6.7">math</A><BR>
+<A HREF="manual.html#pdf-math.abs">math.abs</A><BR>
+<A HREF="manual.html#pdf-math.acos">math.acos</A><BR>
+<A HREF="manual.html#pdf-math.asin">math.asin</A><BR>
+<A HREF="manual.html#pdf-math.atan">math.atan</A><BR>
+<A HREF="manual.html#pdf-math.ceil">math.ceil</A><BR>
+<A HREF="manual.html#pdf-math.cos">math.cos</A><BR>
+<A HREF="manual.html#pdf-math.deg">math.deg</A><BR>
+<A HREF="manual.html#pdf-math.exp">math.exp</A><BR>
+<A HREF="manual.html#pdf-math.floor">math.floor</A><BR>
+<A HREF="manual.html#pdf-math.fmod">math.fmod</A><BR>
+<A HREF="manual.html#pdf-math.huge">math.huge</A><BR>
+<A HREF="manual.html#pdf-math.log">math.log</A><BR>
+<A HREF="manual.html#pdf-math.max">math.max</A><BR>
+<A HREF="manual.html#pdf-math.maxinteger">math.maxinteger</A><BR>
+<A HREF="manual.html#pdf-math.min">math.min</A><BR>
+<A HREF="manual.html#pdf-math.mininteger">math.mininteger</A><BR>
+<A HREF="manual.html#pdf-math.modf">math.modf</A><BR>
+<A HREF="manual.html#pdf-math.pi">math.pi</A><BR>
+<A HREF="manual.html#pdf-math.rad">math.rad</A><BR>
+<A HREF="manual.html#pdf-math.random">math.random</A><BR>
+<A HREF="manual.html#pdf-math.randomseed">math.randomseed</A><BR>
+<A HREF="manual.html#pdf-math.sin">math.sin</A><BR>
+<A HREF="manual.html#pdf-math.sqrt">math.sqrt</A><BR>
+<A HREF="manual.html#pdf-math.tan">math.tan</A><BR>
+<A HREF="manual.html#pdf-math.tointeger">math.tointeger</A><BR>
+<A HREF="manual.html#pdf-math.type">math.type</A><BR>
+<A HREF="manual.html#pdf-math.ult">math.ult</A><BR>
+
+<P>
+<A HREF="manual.html#6.9">os</A><BR>
+<A HREF="manual.html#pdf-os.clock">os.clock</A><BR>
+<A HREF="manual.html#pdf-os.date">os.date</A><BR>
+<A HREF="manual.html#pdf-os.difftime">os.difftime</A><BR>
+<A HREF="manual.html#pdf-os.execute">os.execute</A><BR>
+<A HREF="manual.html#pdf-os.exit">os.exit</A><BR>
+<A HREF="manual.html#pdf-os.getenv">os.getenv</A><BR>
+<A HREF="manual.html#pdf-os.remove">os.remove</A><BR>
+<A HREF="manual.html#pdf-os.rename">os.rename</A><BR>
+<A HREF="manual.html#pdf-os.setlocale">os.setlocale</A><BR>
+<A HREF="manual.html#pdf-os.time">os.time</A><BR>
+<A HREF="manual.html#pdf-os.tmpname">os.tmpname</A><BR>
+
+<P>
+<A HREF="manual.html#6.3">package</A><BR>
+<A HREF="manual.html#pdf-package.config">package.config</A><BR>
+<A HREF="manual.html#pdf-package.cpath">package.cpath</A><BR>
+<A HREF="manual.html#pdf-package.loaded">package.loaded</A><BR>
+<A HREF="manual.html#pdf-package.loadlib">package.loadlib</A><BR>
+<A HREF="manual.html#pdf-package.path">package.path</A><BR>
+<A HREF="manual.html#pdf-package.preload">package.preload</A><BR>
+<A HREF="manual.html#pdf-package.searchers">package.searchers</A><BR>
+<A HREF="manual.html#pdf-package.searchpath">package.searchpath</A><BR>
+
+<P>
+<A HREF="manual.html#6.4">string</A><BR>
+<A HREF="manual.html#pdf-string.byte">string.byte</A><BR>
+<A HREF="manual.html#pdf-string.char">string.char</A><BR>
+<A HREF="manual.html#pdf-string.dump">string.dump</A><BR>
+<A HREF="manual.html#pdf-string.find">string.find</A><BR>
+<A HREF="manual.html#pdf-string.format">string.format</A><BR>
+<A HREF="manual.html#pdf-string.gmatch">string.gmatch</A><BR>
+<A HREF="manual.html#pdf-string.gsub">string.gsub</A><BR>
+<A HREF="manual.html#pdf-string.len">string.len</A><BR>
+<A HREF="manual.html#pdf-string.lower">string.lower</A><BR>
+<A HREF="manual.html#pdf-string.match">string.match</A><BR>
+<A HREF="manual.html#pdf-string.pack">string.pack</A><BR>
+<A HREF="manual.html#pdf-string.packsize">string.packsize</A><BR>
+<A HREF="manual.html#pdf-string.rep">string.rep</A><BR>
+<A HREF="manual.html#pdf-string.reverse">string.reverse</A><BR>
+<A HREF="manual.html#pdf-string.sub">string.sub</A><BR>
+<A HREF="manual.html#pdf-string.unpack">string.unpack</A><BR>
+<A HREF="manual.html#pdf-string.upper">string.upper</A><BR>
+
+<P>
+<A HREF="manual.html#6.6">table</A><BR>
+<A HREF="manual.html#pdf-table.concat">table.concat</A><BR>
+<A HREF="manual.html#pdf-table.insert">table.insert</A><BR>
+<A HREF="manual.html#pdf-table.move">table.move</A><BR>
+<A HREF="manual.html#pdf-table.pack">table.pack</A><BR>
+<A HREF="manual.html#pdf-table.remove">table.remove</A><BR>
+<A HREF="manual.html#pdf-table.sort">table.sort</A><BR>
+<A HREF="manual.html#pdf-table.unpack">table.unpack</A><BR>
+
+<P>
+<A HREF="manual.html#6.5">utf8</A><BR>
+<A HREF="manual.html#pdf-utf8.char">utf8.char</A><BR>
+<A HREF="manual.html#pdf-utf8.charpattern">utf8.charpattern</A><BR>
+<A HREF="manual.html#pdf-utf8.codepoint">utf8.codepoint</A><BR>
+<A HREF="manual.html#pdf-utf8.codes">utf8.codes</A><BR>
+<A HREF="manual.html#pdf-utf8.len">utf8.len</A><BR>
+<A HREF="manual.html#pdf-utf8.offset">utf8.offset</A><BR>
+
+<H3><A NAME="metamethods">metamethods</A></H3>
+<P>
+<A HREF="manual.html#2.4">__add</A><BR>
+<A HREF="manual.html#2.4">__band</A><BR>
+<A HREF="manual.html#2.4">__bnot</A><BR>
+<A HREF="manual.html#2.4">__bor</A><BR>
+<A HREF="manual.html#2.4">__bxor</A><BR>
+<A HREF="manual.html#2.4">__call</A><BR>
+<A HREF="manual.html#3.3.8">__close</A><BR>
+<A HREF="manual.html#2.4">__concat</A><BR>
+<A HREF="manual.html#2.4">__div</A><BR>
+<A HREF="manual.html#2.4">__eq</A><BR>
+<A HREF="manual.html#2.5.3">__gc</A><BR>
+<A HREF="manual.html#2.4">__idiv</A><BR>
+<A HREF="manual.html#2.4">__index</A><BR>
+<A HREF="manual.html#2.4">__le</A><BR>
+<A HREF="manual.html#2.4">__len</A><BR>
+<A HREF="manual.html#2.4">__lt</A><BR>
+<A HREF="manual.html#pdf-getmetatable">__metatable</A><BR>
+<A HREF="manual.html#2.4">__mod</A><BR>
+<A HREF="manual.html#2.5.4">__mode</A><BR>
+<A HREF="manual.html#2.4">__mul</A><BR>
+<A HREF="manual.html#luaL_newmetatable">__name</A><BR>
+<A HREF="manual.html#2.4">__newindex</A><BR>
+<A HREF="manual.html#pdf-pairs">__pairs</A><BR>
+<A HREF="manual.html#2.4">__pow</A><BR>
+<A HREF="manual.html#2.4">__shl</A><BR>
+<A HREF="manual.html#2.4">__shr</A><BR>
+<A HREF="manual.html#2.4">__sub</A><BR>
+<A HREF="manual.html#pdf-tostring">__tostring</A><BR>
+<A HREF="manual.html#2.4">__unm</A><BR>
+
+<H3><A NAME="env">environment<BR>variables</A></H3>
+<P>
+<A HREF="manual.html#pdf-LUA_CPATH">LUA_CPATH</A><BR>
+<A HREF="manual.html#pdf-LUA_CPATH_5_4">LUA_CPATH_5_4</A><BR>
+<A HREF="manual.html#pdf-LUA_INIT">LUA_INIT</A><BR>
+<A HREF="manual.html#pdf-LUA_INIT_5_4">LUA_INIT_5_4</A><BR>
+<A HREF="manual.html#pdf-LUA_PATH">LUA_PATH</A><BR>
+<A HREF="manual.html#pdf-LUA_PATH_5_4">LUA_PATH_5_4</A><BR>
+
+</TD>
+<TD>
+<H3><A NAME="api">C API</A></H3>
+<P>
+<A HREF="manual.html#lua_Alloc">lua_Alloc</A><BR>
+<A HREF="manual.html#lua_CFunction">lua_CFunction</A><BR>
+<A HREF="manual.html#lua_Debug">lua_Debug</A><BR>
+<A HREF="manual.html#lua_Hook">lua_Hook</A><BR>
+<A HREF="manual.html#lua_Integer">lua_Integer</A><BR>
+<A HREF="manual.html#lua_KContext">lua_KContext</A><BR>
+<A HREF="manual.html#lua_KFunction">lua_KFunction</A><BR>
+<A HREF="manual.html#lua_Number">lua_Number</A><BR>
+<A HREF="manual.html#lua_Reader">lua_Reader</A><BR>
+<A HREF="manual.html#lua_State">lua_State</A><BR>
+<A HREF="manual.html#lua_Unsigned">lua_Unsigned</A><BR>
+<A HREF="manual.html#lua_WarnFunction">lua_WarnFunction</A><BR>
+<A HREF="manual.html#lua_Writer">lua_Writer</A><BR>
+
+<P>
+<A HREF="manual.html#lua_absindex">lua_absindex</A><BR>
+<A HREF="manual.html#lua_arith">lua_arith</A><BR>
+<A HREF="manual.html#lua_atpanic">lua_atpanic</A><BR>
+<A HREF="manual.html#lua_call">lua_call</A><BR>
+<A HREF="manual.html#lua_callk">lua_callk</A><BR>
+<A HREF="manual.html#lua_checkstack">lua_checkstack</A><BR>
+<A HREF="manual.html#lua_close">lua_close</A><BR>
+<A HREF="manual.html#lua_compare">lua_compare</A><BR>
+<A HREF="manual.html#lua_concat">lua_concat</A><BR>
+<A HREF="manual.html#lua_copy">lua_copy</A><BR>
+<A HREF="manual.html#lua_createtable">lua_createtable</A><BR>
+<A HREF="manual.html#lua_dump">lua_dump</A><BR>
+<A HREF="manual.html#lua_error">lua_error</A><BR>
+<A HREF="manual.html#lua_gc">lua_gc</A><BR>
+<A HREF="manual.html#lua_getallocf">lua_getallocf</A><BR>
+<A HREF="manual.html#lua_getextraspace">lua_getextraspace</A><BR>
+<A HREF="manual.html#lua_getfield">lua_getfield</A><BR>
+<A HREF="manual.html#lua_getglobal">lua_getglobal</A><BR>
+<A HREF="manual.html#lua_gethook">lua_gethook</A><BR>
+<A HREF="manual.html#lua_gethookcount">lua_gethookcount</A><BR>
+<A HREF="manual.html#lua_gethookmask">lua_gethookmask</A><BR>
+<A HREF="manual.html#lua_geti">lua_geti</A><BR>
+<A HREF="manual.html#lua_getinfo">lua_getinfo</A><BR>
+<A HREF="manual.html#lua_getiuservalue">lua_getiuservalue</A><BR>
+<A HREF="manual.html#lua_getlocal">lua_getlocal</A><BR>
+<A HREF="manual.html#lua_getmetatable">lua_getmetatable</A><BR>
+<A HREF="manual.html#lua_getstack">lua_getstack</A><BR>
+<A HREF="manual.html#lua_gettable">lua_gettable</A><BR>
+<A HREF="manual.html#lua_gettop">lua_gettop</A><BR>
+<A HREF="manual.html#lua_getupvalue">lua_getupvalue</A><BR>
+<A HREF="manual.html#lua_insert">lua_insert</A><BR>
+<A HREF="manual.html#lua_isboolean">lua_isboolean</A><BR>
+<A HREF="manual.html#lua_iscfunction">lua_iscfunction</A><BR>
+<A HREF="manual.html#lua_isfunction">lua_isfunction</A><BR>
+<A HREF="manual.html#lua_isinteger">lua_isinteger</A><BR>
+<A HREF="manual.html#lua_islightuserdata">lua_islightuserdata</A><BR>
+<A HREF="manual.html#lua_isnil">lua_isnil</A><BR>
+<A HREF="manual.html#lua_isnone">lua_isnone</A><BR>
+<A HREF="manual.html#lua_isnoneornil">lua_isnoneornil</A><BR>
+<A HREF="manual.html#lua_isnumber">lua_isnumber</A><BR>
+<A HREF="manual.html#lua_isstring">lua_isstring</A><BR>
+<A HREF="manual.html#lua_istable">lua_istable</A><BR>
+<A HREF="manual.html#lua_isthread">lua_isthread</A><BR>
+<A HREF="manual.html#lua_isuserdata">lua_isuserdata</A><BR>
+<A HREF="manual.html#lua_isyieldable">lua_isyieldable</A><BR>
+<A HREF="manual.html#lua_len">lua_len</A><BR>
+<A HREF="manual.html#lua_load">lua_load</A><BR>
+<A HREF="manual.html#lua_newstate">lua_newstate</A><BR>
+<A HREF="manual.html#lua_newtable">lua_newtable</A><BR>
+<A HREF="manual.html#lua_newthread">lua_newthread</A><BR>
+<A HREF="manual.html#lua_newuserdatauv">lua_newuserdatauv</A><BR>
+<A HREF="manual.html#lua_next">lua_next</A><BR>
+<A HREF="manual.html#lua_numbertointeger">lua_numbertointeger</A><BR>
+<A HREF="manual.html#lua_pcall">lua_pcall</A><BR>
+<A HREF="manual.html#lua_pcallk">lua_pcallk</A><BR>
+<A HREF="manual.html#lua_pop">lua_pop</A><BR>
+<A HREF="manual.html#lua_pushboolean">lua_pushboolean</A><BR>
+<A HREF="manual.html#lua_pushcclosure">lua_pushcclosure</A><BR>
+<A HREF="manual.html#lua_pushcfunction">lua_pushcfunction</A><BR>
+<A HREF="manual.html#lua_pushfstring">lua_pushfstring</A><BR>
+<A HREF="manual.html#lua_pushglobaltable">lua_pushglobaltable</A><BR>
+<A HREF="manual.html#lua_pushinteger">lua_pushinteger</A><BR>
+<A HREF="manual.html#lua_pushlightuserdata">lua_pushlightuserdata</A><BR>
+<A HREF="manual.html#lua_pushliteral">lua_pushliteral</A><BR>
+<A HREF="manual.html#lua_pushlstring">lua_pushlstring</A><BR>
+<A HREF="manual.html#lua_pushnil">lua_pushnil</A><BR>
+<A HREF="manual.html#lua_pushnumber">lua_pushnumber</A><BR>
+<A HREF="manual.html#lua_pushstring">lua_pushstring</A><BR>
+<A HREF="manual.html#lua_pushthread">lua_pushthread</A><BR>
+<A HREF="manual.html#lua_pushvalue">lua_pushvalue</A><BR>
+<A HREF="manual.html#lua_pushvfstring">lua_pushvfstring</A><BR>
+<A HREF="manual.html#lua_rawequal">lua_rawequal</A><BR>
+<A HREF="manual.html#lua_rawget">lua_rawget</A><BR>
+<A HREF="manual.html#lua_rawgeti">lua_rawgeti</A><BR>
+<A HREF="manual.html#lua_rawgetp">lua_rawgetp</A><BR>
+<A HREF="manual.html#lua_rawlen">lua_rawlen</A><BR>
+<A HREF="manual.html#lua_rawset">lua_rawset</A><BR>
+<A HREF="manual.html#lua_rawseti">lua_rawseti</A><BR>
+<A HREF="manual.html#lua_rawsetp">lua_rawsetp</A><BR>
+<A HREF="manual.html#lua_register">lua_register</A><BR>
+<A HREF="manual.html#lua_remove">lua_remove</A><BR>
+<A HREF="manual.html#lua_replace">lua_replace</A><BR>
+<A HREF="manual.html#lua_resetthread">lua_resetthread</A><BR>
+<A HREF="manual.html#lua_resume">lua_resume</A><BR>
+<A HREF="manual.html#lua_rotate">lua_rotate</A><BR>
+<A HREF="manual.html#lua_setallocf">lua_setallocf</A><BR>
+<A HREF="manual.html#lua_setcstacklimit">lua_setcstacklimit</A><BR>
+<A HREF="manual.html#lua_setfield">lua_setfield</A><BR>
+<A HREF="manual.html#lua_setglobal">lua_setglobal</A><BR>
+<A HREF="manual.html#lua_sethook">lua_sethook</A><BR>
+<A HREF="manual.html#lua_seti">lua_seti</A><BR>
+<A HREF="manual.html#lua_setiuservalue">lua_setiuservalue</A><BR>
+<A HREF="manual.html#lua_setlocal">lua_setlocal</A><BR>
+<A HREF="manual.html#lua_setmetatable">lua_setmetatable</A><BR>
+<A HREF="manual.html#lua_settable">lua_settable</A><BR>
+<A HREF="manual.html#lua_settop">lua_settop</A><BR>
+<A HREF="manual.html#lua_setupvalue">lua_setupvalue</A><BR>
+<A HREF="manual.html#lua_setwarnf">lua_setwarnf</A><BR>
+<A HREF="manual.html#lua_status">lua_status</A><BR>
+<A HREF="manual.html#lua_stringtonumber">lua_stringtonumber</A><BR>
+<A HREF="manual.html#lua_toboolean">lua_toboolean</A><BR>
+<A HREF="manual.html#lua_tocfunction">lua_tocfunction</A><BR>
+<A HREF="manual.html#lua_toclose">lua_toclose</A><BR>
+<A HREF="manual.html#lua_tointeger">lua_tointeger</A><BR>
+<A HREF="manual.html#lua_tointegerx">lua_tointegerx</A><BR>
+<A HREF="manual.html#lua_tolstring">lua_tolstring</A><BR>
+<A HREF="manual.html#lua_tonumber">lua_tonumber</A><BR>
+<A HREF="manual.html#lua_tonumberx">lua_tonumberx</A><BR>
+<A HREF="manual.html#lua_topointer">lua_topointer</A><BR>
+<A HREF="manual.html#lua_tostring">lua_tostring</A><BR>
+<A HREF="manual.html#lua_tothread">lua_tothread</A><BR>
+<A HREF="manual.html#lua_touserdata">lua_touserdata</A><BR>
+<A HREF="manual.html#lua_type">lua_type</A><BR>
+<A HREF="manual.html#lua_typename">lua_typename</A><BR>
+<A HREF="manual.html#lua_upvalueid">lua_upvalueid</A><BR>
+<A HREF="manual.html#lua_upvalueindex">lua_upvalueindex</A><BR>
+<A HREF="manual.html#lua_upvaluejoin">lua_upvaluejoin</A><BR>
+<A HREF="manual.html#lua_version">lua_version</A><BR>
+<A HREF="manual.html#lua_warning">lua_warning</A><BR>
+<A HREF="manual.html#lua_xmove">lua_xmove</A><BR>
+<A HREF="manual.html#lua_yield">lua_yield</A><BR>
+<A HREF="manual.html#lua_yieldk">lua_yieldk</A><BR>
+
+</TD>
+<TD>
+<H3><A NAME="auxlib">auxiliary library</A></H3>
+<P>
+<A HREF="manual.html#luaL_Buffer">luaL_Buffer</A><BR>
+<A HREF="manual.html#luaL_Reg">luaL_Reg</A><BR>
+<A HREF="manual.html#luaL_Stream">luaL_Stream</A><BR>
+
+<P>
+<A HREF="manual.html#luaL_addchar">luaL_addchar</A><BR>
+<A HREF="manual.html#luaL_addgsub">luaL_addgsub</A><BR>
+<A HREF="manual.html#luaL_addlstring">luaL_addlstring</A><BR>
+<A HREF="manual.html#luaL_addsize">luaL_addsize</A><BR>
+<A HREF="manual.html#luaL_addstring">luaL_addstring</A><BR>
+<A HREF="manual.html#luaL_addvalue">luaL_addvalue</A><BR>
+<A HREF="manual.html#luaL_argcheck">luaL_argcheck</A><BR>
+<A HREF="manual.html#luaL_argerror">luaL_argerror</A><BR>
+<A HREF="manual.html#luaL_argexpected">luaL_argexpected</A><BR>
+<A HREF="manual.html#luaL_buffaddr">luaL_buffaddr</A><BR>
+<A HREF="manual.html#luaL_buffinit">luaL_buffinit</A><BR>
+<A HREF="manual.html#luaL_buffinitsize">luaL_buffinitsize</A><BR>
+<A HREF="manual.html#luaL_bufflen">luaL_bufflen</A><BR>
+<A HREF="manual.html#luaL_buffsub">luaL_buffsub</A><BR>
+<A HREF="manual.html#luaL_callmeta">luaL_callmeta</A><BR>
+<A HREF="manual.html#luaL_checkany">luaL_checkany</A><BR>
+<A HREF="manual.html#luaL_checkinteger">luaL_checkinteger</A><BR>
+<A HREF="manual.html#luaL_checklstring">luaL_checklstring</A><BR>
+<A HREF="manual.html#luaL_checknumber">luaL_checknumber</A><BR>
+<A HREF="manual.html#luaL_checkoption">luaL_checkoption</A><BR>
+<A HREF="manual.html#luaL_checkstack">luaL_checkstack</A><BR>
+<A HREF="manual.html#luaL_checkstring">luaL_checkstring</A><BR>
+<A HREF="manual.html#luaL_checktype">luaL_checktype</A><BR>
+<A HREF="manual.html#luaL_checkudata">luaL_checkudata</A><BR>
+<A HREF="manual.html#luaL_checkversion">luaL_checkversion</A><BR>
+<A HREF="manual.html#luaL_dofile">luaL_dofile</A><BR>
+<A HREF="manual.html#luaL_dostring">luaL_dostring</A><BR>
+<A HREF="manual.html#luaL_error">luaL_error</A><BR>
+<A HREF="manual.html#luaL_execresult">luaL_execresult</A><BR>
+<A HREF="manual.html#luaL_fileresult">luaL_fileresult</A><BR>
+<A HREF="manual.html#luaL_getmetafield">luaL_getmetafield</A><BR>
+<A HREF="manual.html#luaL_getmetatable">luaL_getmetatable</A><BR>
+<A HREF="manual.html#luaL_getsubtable">luaL_getsubtable</A><BR>
+<A HREF="manual.html#luaL_gsub">luaL_gsub</A><BR>
+<A HREF="manual.html#luaL_len">luaL_len</A><BR>
+<A HREF="manual.html#luaL_loadbuffer">luaL_loadbuffer</A><BR>
+<A HREF="manual.html#luaL_loadbufferx">luaL_loadbufferx</A><BR>
+<A HREF="manual.html#luaL_loadfile">luaL_loadfile</A><BR>
+<A HREF="manual.html#luaL_loadfilex">luaL_loadfilex</A><BR>
+<A HREF="manual.html#luaL_loadstring">luaL_loadstring</A><BR>
+<A HREF="manual.html#luaL_newlib">luaL_newlib</A><BR>
+<A HREF="manual.html#luaL_newlibtable">luaL_newlibtable</A><BR>
+<A HREF="manual.html#luaL_newmetatable">luaL_newmetatable</A><BR>
+<A HREF="manual.html#luaL_newstate">luaL_newstate</A><BR>
+<A HREF="manual.html#luaL_openlibs">luaL_openlibs</A><BR>
+<A HREF="manual.html#luaL_opt">luaL_opt</A><BR>
+<A HREF="manual.html#luaL_optinteger">luaL_optinteger</A><BR>
+<A HREF="manual.html#luaL_optlstring">luaL_optlstring</A><BR>
+<A HREF="manual.html#luaL_optnumber">luaL_optnumber</A><BR>
+<A HREF="manual.html#luaL_optstring">luaL_optstring</A><BR>
+<A HREF="manual.html#luaL_prepbuffer">luaL_prepbuffer</A><BR>
+<A HREF="manual.html#luaL_prepbuffsize">luaL_prepbuffsize</A><BR>
+<A HREF="manual.html#luaL_pushfail">luaL_pushfail</A><BR>
+<A HREF="manual.html#luaL_pushresult">luaL_pushresult</A><BR>
+<A HREF="manual.html#luaL_pushresultsize">luaL_pushresultsize</A><BR>
+<A HREF="manual.html#luaL_ref">luaL_ref</A><BR>
+<A HREF="manual.html#luaL_requiref">luaL_requiref</A><BR>
+<A HREF="manual.html#luaL_setfuncs">luaL_setfuncs</A><BR>
+<A HREF="manual.html#luaL_setmetatable">luaL_setmetatable</A><BR>
+<A HREF="manual.html#luaL_testudata">luaL_testudata</A><BR>
+<A HREF="manual.html#luaL_tolstring">luaL_tolstring</A><BR>
+<A HREF="manual.html#luaL_traceback">luaL_traceback</A><BR>
+<A HREF="manual.html#luaL_typeerror">luaL_typeerror</A><BR>
+<A HREF="manual.html#luaL_typename">luaL_typename</A><BR>
+<A HREF="manual.html#luaL_unref">luaL_unref</A><BR>
+<A HREF="manual.html#luaL_where">luaL_where</A><BR>
+
+<H3><A NAME="library">standard library</A></H3>
+<P>
+<A HREF="manual.html#pdf-luaopen_base">luaopen_base</A><BR>
+<A HREF="manual.html#pdf-luaopen_coroutine">luaopen_coroutine</A><BR>
+<A HREF="manual.html#pdf-luaopen_debug">luaopen_debug</A><BR>
+<A HREF="manual.html#pdf-luaopen_io">luaopen_io</A><BR>
+<A HREF="manual.html#pdf-luaopen_math">luaopen_math</A><BR>
+<A HREF="manual.html#pdf-luaopen_os">luaopen_os</A><BR>
+<A HREF="manual.html#pdf-luaopen_package">luaopen_package</A><BR>
+<A HREF="manual.html#pdf-luaopen_string">luaopen_string</A><BR>
+<A HREF="manual.html#pdf-luaopen_table">luaopen_table</A><BR>
+<A HREF="manual.html#pdf-luaopen_utf8">luaopen_utf8</A><BR>
+
+<H3><A NAME="constants">constants</A></H3>
+<P>
+<A HREF="manual.html#pdf-LUA_ERRERR">LUA_ERRERR</A><BR>
+<A HREF="manual.html#pdf-LUA_ERRFILE">LUA_ERRFILE</A><BR>
+<A HREF="manual.html#pdf-LUA_ERRMEM">LUA_ERRMEM</A><BR>
+<A HREF="manual.html#pdf-LUA_ERRRUN">LUA_ERRRUN</A><BR>
+<A HREF="manual.html#pdf-LUA_ERRSYNTAX">LUA_ERRSYNTAX</A><BR>
+<A HREF="manual.html#pdf-LUA_HOOKCALL">LUA_HOOKCALL</A><BR>
+<A HREF="manual.html#pdf-LUA_HOOKCOUNT">LUA_HOOKCOUNT</A><BR>
+<A HREF="manual.html#pdf-LUA_HOOKLINE">LUA_HOOKLINE</A><BR>
+<A HREF="manual.html#pdf-LUA_HOOKRET">LUA_HOOKRET</A><BR>
+<A HREF="manual.html#pdf-LUA_HOOKTAILCALL">LUA_HOOKTAILCALL</A><BR>
+<A HREF="manual.html#pdf-LUAL_BUFFERSIZE">LUAL_BUFFERSIZE</A><BR>
+<A HREF="manual.html#pdf-LUA_MASKCALL">LUA_MASKCALL</A><BR>
+<A HREF="manual.html#pdf-LUA_MASKCOUNT">LUA_MASKCOUNT</A><BR>
+<A HREF="manual.html#pdf-LUA_MASKLINE">LUA_MASKLINE</A><BR>
+<A HREF="manual.html#pdf-LUA_MASKRET">LUA_MASKRET</A><BR>
+<A HREF="manual.html#pdf-LUA_MAXINTEGER">LUA_MAXINTEGER</A><BR>
+<A HREF="manual.html#pdf-LUA_MININTEGER">LUA_MININTEGER</A><BR>
+<A HREF="manual.html#pdf-LUA_MINSTACK">LUA_MINSTACK</A><BR>
+<A HREF="manual.html#pdf-LUA_MULTRET">LUA_MULTRET</A><BR>
+<A HREF="manual.html#pdf-LUA_NOREF">LUA_NOREF</A><BR>
+<A HREF="manual.html#pdf-LUA_OK">LUA_OK</A><BR>
+<A HREF="manual.html#pdf-LUA_OPADD">LUA_OPADD</A><BR>
+<A HREF="manual.html#pdf-LUA_OPBAND">LUA_OPBAND</A><BR>
+<A HREF="manual.html#pdf-LUA_OPBNOT">LUA_OPBNOT</A><BR>
+<A HREF="manual.html#pdf-LUA_OPBOR">LUA_OPBOR</A><BR>
+<A HREF="manual.html#pdf-LUA_OPBXOR">LUA_OPBXOR</A><BR>
+<A HREF="manual.html#pdf-LUA_OPDIV">LUA_OPDIV</A><BR>
+<A HREF="manual.html#pdf-LUA_OPEQ">LUA_OPEQ</A><BR>
+<A HREF="manual.html#pdf-LUA_OPIDIV">LUA_OPIDIV</A><BR>
+<A HREF="manual.html#pdf-LUA_OPLE">LUA_OPLE</A><BR>
+<A HREF="manual.html#pdf-LUA_OPLT">LUA_OPLT</A><BR>
+<A HREF="manual.html#pdf-LUA_OPMOD">LUA_OPMOD</A><BR>
+<A HREF="manual.html#pdf-LUA_OPMUL">LUA_OPMUL</A><BR>
+<A HREF="manual.html#pdf-LUA_OPPOW">LUA_OPPOW</A><BR>
+<A HREF="manual.html#pdf-LUA_OPSHL">LUA_OPSHL</A><BR>
+<A HREF="manual.html#pdf-LUA_OPSHR">LUA_OPSHR</A><BR>
+<A HREF="manual.html#pdf-LUA_OPSUB">LUA_OPSUB</A><BR>
+<A HREF="manual.html#pdf-LUA_OPUNM">LUA_OPUNM</A><BR>
+<A HREF="manual.html#pdf-LUA_REFNIL">LUA_REFNIL</A><BR>
+<A HREF="manual.html#pdf-LUA_REGISTRYINDEX">LUA_REGISTRYINDEX</A><BR>
+<A HREF="manual.html#pdf-LUA_RIDX_GLOBALS">LUA_RIDX_GLOBALS</A><BR>
+<A HREF="manual.html#pdf-LUA_RIDX_MAINTHREAD">LUA_RIDX_MAINTHREAD</A><BR>
+<A HREF="manual.html#pdf-LUA_TBOOLEAN">LUA_TBOOLEAN</A><BR>
+<A HREF="manual.html#pdf-LUA_TFUNCTION">LUA_TFUNCTION</A><BR>
+<A HREF="manual.html#pdf-LUA_TLIGHTUSERDATA">LUA_TLIGHTUSERDATA</A><BR>
+<A HREF="manual.html#pdf-LUA_TNIL">LUA_TNIL</A><BR>
+<A HREF="manual.html#pdf-LUA_TNONE">LUA_TNONE</A><BR>
+<A HREF="manual.html#pdf-LUA_TNUMBER">LUA_TNUMBER</A><BR>
+<A HREF="manual.html#pdf-LUA_TSTRING">LUA_TSTRING</A><BR>
+<A HREF="manual.html#pdf-LUA_TTABLE">LUA_TTABLE</A><BR>
+<A HREF="manual.html#pdf-LUA_TTHREAD">LUA_TTHREAD</A><BR>
+<A HREF="manual.html#pdf-LUA_TUSERDATA">LUA_TUSERDATA</A><BR>
+<A HREF="manual.html#pdf-LUA_USE_APICHECK">LUA_USE_APICHECK</A><BR>
+<A HREF="manual.html#pdf-LUA_YIELD">LUA_YIELD</A><BR>
+
+</TD>
+</TR>
+</TABLE>
+
+<P CLASS="footer">
+Last update:
+Sat May 30 08:22:18 -03 2020
+</P>
+<!--
+Last change: revised for Lua 5.4.0 (final)
+-->
+
+</BODY>
+</HTML>
diff --git a/test/external/lua-5.4.0/doc/index.css b/test/external/lua-5.4.0/doc/index.css
new file mode 100644
index 0000000..c961835
--- /dev/null
+++ b/test/external/lua-5.4.0/doc/index.css
@@ -0,0 +1,21 @@
+ul {
+	list-style-type: none ;
+}
+
+ul.contents {
+	padding: 0 ;
+}
+
+table {
+	border: none ;
+	border-spacing: 0 ;
+	border-collapse: collapse ;
+}
+
+td {
+	vertical-align: top ;
+	padding: 0 ;
+	text-align: left ;
+	line-height: 1.25 ;
+	width: 15% ;
+}
diff --git a/test/external/lua-5.4.0/doc/logo.gif b/test/external/lua-5.4.0/doc/logo.gif
new file mode 100644
index 0000000..5c77eac
--- /dev/null
+++ b/test/external/lua-5.4.0/doc/logo.gif
diff --git a/test/external/lua-5.4.0/doc/lua.1 b/test/external/lua-5.4.0/doc/lua.1
new file mode 100644
index 0000000..a46a1a6
--- /dev/null
+++ b/test/external/lua-5.4.0/doc/lua.1
@@ -0,0 +1,149 @@
+.\" $Id: lua.man,v 1.14 2020/05/21 19:31:21 lhf Exp $
+.TH LUA 1 "$Date: 2020/05/21 19:31:21 $"
+.SH NAME
+lua \- Lua interpreter
+.SH SYNOPSIS
+.B lua
+[
+.I options
+]
+[
+.I script
+[
+.I args
+]
+]
+.SH DESCRIPTION
+.B lua
+is the standalone Lua interpreter.
+It loads and executes Lua programs,
+either in textual source form or
+in precompiled binary form.
+(Precompiled binaries are output by
+.BR luac ,
+the Lua compiler.)
+.B lua
+can be used as a batch interpreter and also interactively.
+.LP
+After handling the
+.IR options ,
+the Lua program in file
+.I script
+is loaded and executed.
+The
+.I args
+are available to
+.I script
+as strings in a global table named
+.B arg
+and also as arguments to its main function.
+When called without arguments,
+.B lua
+behaves as
+.B "lua \-v \-i"
+if the standard input is a terminal,
+and as
+.B "lua \-"
+otherwise.
+.LP
+In interactive mode,
+.B lua
+prompts the user,
+reads lines from the standard input,
+and executes them as they are read.
+If the line contains an expression,
+then the line is evaluated and the result is printed.
+If a line does not contain a complete statement,
+then a secondary prompt is displayed and
+lines are read until a complete statement is formed or
+a syntax error is found.
+.LP
+Before handling command line options and scripts,
+.B lua
+checks the contents of the environment variables
+.B LUA_INIT_5_4
+and
+.BR LUA_INIT ,
+in that order.
+If the contents are of the form
+.RI '@ filename ',
+then
+.I filename
+is executed.
+Otherwise, the contents are assumed to be a Lua statement and is executed.
+When
+.B LUA_INIT_5_4
+is defined,
+.B LUA_INIT
+is ignored.
+.SH OPTIONS
+.TP
+.BI \-e " stat"
+execute statement
+.IR stat .
+.TP
+.B \-i
+enter interactive mode after executing
+.IR script .
+.TP
+.BI \-l " name"
+require library
+.I name
+into global
+.IR name .
+.TP
+.B \-v
+show version information.
+.TP
+.B \-E
+ignore environment variables.
+.TP
+.B \-W
+turn warnings on.
+.TP
+.B \-\-
+stop handling options.
+.TP
+.B \-
+stop handling options and execute the standard input as a file.
+.SH ENVIRONMENT VARIABLES
+The following environment variables affect the execution of
+.BR lua .
+When defined,
+the version-specific variants take priority
+and the version-neutral variants are ignored.
+.TP
+.B LUA_INIT, LUA_INIT_5_4
+Code to be executed before command line options and scripts.
+.TP
+.B LUA_PATH, LUA_PATH_5_4
+Initial value of package.cpath,
+the path used by require to search for Lua loaders.
+.TP
+.B LUA_CPATH, LUA_CPATH_5_4
+Initial value of package.cpath,
+the path used by require to search for C loaders.
+.SH EXIT STATUS
+If a script calls os.exit,
+then
+.B lua
+exits with the given exit status.
+Otherwise,
+.B lua
+exits
+with EXIT_SUCCESS (0 on POSIX systems) if there were no errors
+and
+with EXIT_FAILURE (1 on POSIX systems) if there were errors.
+Errors raised in interactive mode do not cause exits.
+.SH DIAGNOSTICS
+Error messages should be self explanatory.
+.SH "SEE ALSO"
+.BR luac (1)
+.br
+The documentation at lua.org,
+especially section 7 of the reference manual.
+.SH AUTHORS
+R. Ierusalimschy,
+L. H. de Figueiredo,
+W. Celes
+.\" EOF
diff --git a/test/external/lua-5.4.0/doc/lua.css b/test/external/lua-5.4.0/doc/lua.css
new file mode 100644
index 0000000..cbd0799
--- /dev/null
+++ b/test/external/lua-5.4.0/doc/lua.css
@@ -0,0 +1,161 @@
+html {
+	background-color: #F8F8F8 ;
+}
+
+body {
+	background-color: #FFFFFF ;
+	color: #000000 ;
+	font-family: Helvetica, Arial, sans-serif ;
+	text-align: justify ;
+	line-height: 1.25 ;
+	margin: 16px auto ;
+	padding: 32px ;
+	border: solid #ccc 1px ;
+	border-radius: 20px ;
+	max-width: 70em ;
+	width: 90% ;
+}
+
+h1, h2, h3, h4 {
+	color: #000080 ;
+	font-family: Verdana, Geneva, sans-serif ;
+	font-weight: normal ;
+	font-style: normal ;
+	text-align: left ;
+}
+
+h1 {
+	font-size: 28pt ;
+}
+
+h1 img {
+	vertical-align: text-bottom ;
+}
+
+h2:before {
+	content: "\2756" ;
+	padding-right: 0.5em ;
+}
+
+a {
+	text-decoration: none ;
+}
+
+a:link {
+	color: #000080 ;
+}
+
+a:link:hover, a:visited:hover {
+	background-color: #D0D0FF ;
+	color: #000080 ;
+	border-radius: 4px ;
+}
+
+a:link:active, a:visited:active {
+	color: #FF0000 ;
+}
+
+div.menubar {
+	padding-bottom: 0.5em ;
+}
+
+p.menubar {
+	margin-left: 2.5em ;
+}
+
+.menubar a:hover  {
+	margin: -3px -3px -3px -3px ;
+	padding: 3px  3px  3px  3px ;
+	border-radius: 4px ;
+}
+
+:target {
+	background-color: #F0F0F0 ;
+	margin: -8px ;
+	padding: 8px ;
+	border-radius: 8px ;
+	outline: none ;
+}
+
+hr {
+	display: none ;
+}
+
+table hr {
+	background-color: #a0a0a0 ;
+	color: #a0a0a0 ;
+	border: 0 ;
+	height: 1px ;
+	display: block ;
+}
+
+.footer {
+	color: gray ;
+	font-size: x-small ;
+	text-transform: lowercase ;
+}
+
+input[type=text] {
+	border: solid #a0a0a0 2px ;
+	border-radius: 2em ;
+	background-image: url('images/search.png') ;
+	background-repeat: no-repeat ;
+	background-position: 4px center ;
+	padding-left: 20px ;
+	height: 2em ;
+}
+
+pre.session {
+	background-color: #F8F8F8 ;
+	padding: 1em ;
+	border-radius: 8px ;
+}
+
+table {
+	border: none ;
+	border-spacing: 0 ;
+	border-collapse: collapse ;
+}
+
+td {
+	padding: 0 ;
+	margin: 0 ;
+}
+
+td.gutter {
+	width: 4% ;
+}
+
+table.columns td {
+	vertical-align: top ;
+	padding-bottom: 1em ;
+	text-align: justify ;
+	line-height: 1.25 ;
+}
+
+table.book td {
+	vertical-align: top ;
+}
+
+table.book td.cover {
+	padding-right: 1em ;
+}
+
+table.book img {
+	border: solid #000080 1px ;
+}
+
+table.book span {
+	font-size: small ;
+	text-align: left ;
+	display: block ;
+	margin-top: 0.25em ;
+}
+
+p.logos a:link:hover, p.logos a:visited:hover {
+	background-color: inherit ;
+}
+
+img {
+	background-color: white ;
+}
diff --git a/test/external/lua-5.4.0/doc/luac.1 b/test/external/lua-5.4.0/doc/luac.1
new file mode 100644
index 0000000..33a4ed0
--- /dev/null
+++ b/test/external/lua-5.4.0/doc/luac.1
@@ -0,0 +1,118 @@
+.\" $Id: luac.man,v 1.29 2011/11/16 13:53:40 lhf Exp $
+.TH LUAC 1 "$Date: 2011/11/16 13:53:40 $"
+.SH NAME
+luac \- Lua compiler
+.SH SYNOPSIS
+.B luac
+[
+.I options
+] [
+.I filenames
+]
+.SH DESCRIPTION
+.B luac
+is the Lua compiler.
+It translates programs written in the Lua programming language
+into binary files containing precompiled chunks
+that can be later loaded and executed.
+.LP
+The main advantages of precompiling chunks are:
+faster loading,
+protecting source code from accidental user changes,
+and
+off-line syntax checking.
+Precompiling does not imply faster execution
+because in Lua chunks are always compiled into bytecodes before being executed.
+.B luac
+simply allows those bytecodes to be saved in a file for later execution.
+Precompiled chunks are not necessarily smaller than the corresponding source.
+The main goal in precompiling is faster loading.
+.LP
+In the command line,
+you can mix
+text files containing Lua source and
+binary files containing precompiled chunks.
+.B luac
+produces a single output file containing the combined bytecodes
+for all files given.
+Executing the combined file is equivalent to executing the given files.
+By default,
+the output file is named
+.BR luac.out ,
+but you can change this with the
+.B \-o
+option.
+.LP
+Precompiled chunks are
+.I not
+portable across different architectures.
+Moreover,
+the internal format of precompiled chunks
+is likely to change when a new version of Lua is released.
+Make sure you save the source files of all Lua programs that you precompile.
+.LP
+.SH OPTIONS
+.TP
+.B \-l
+produce a listing of the compiled bytecode for Lua's virtual machine.
+Listing bytecodes is useful to learn about Lua's virtual machine.
+If no files are given, then
+.B luac
+loads
+.B luac.out
+and lists its contents.
+Use
+.B \-l \-l
+for a full listing.
+.TP
+.BI \-o " file"
+output to
+.IR file ,
+instead of the default
+.BR luac.out .
+(You can use
+.B "'\-'"
+for standard output,
+but not on platforms that open standard output in text mode.)
+The output file may be one of the given files because
+all files are loaded before the output file is written.
+Be careful not to overwrite precious files.
+.TP
+.B \-p
+load files but do not generate any output file.
+Used mainly for syntax checking and for testing precompiled chunks:
+corrupted files will probably generate errors when loaded.
+If no files are given, then
+.B luac
+loads
+.B luac.out
+and tests its contents.
+No messages are displayed if the file loads without errors.
+.TP
+.B \-s
+strip debug information before writing the output file.
+This saves some space in very large chunks,
+but if errors occur when running a stripped chunk,
+then the error messages may not contain the full information they usually do.
+In particular,
+line numbers and names of local variables are lost.
+.TP
+.B \-v
+show version information.
+.TP
+.B \-\-
+stop handling options.
+.TP
+.B \-
+stop handling options and process standard input.
+.SH "SEE ALSO"
+.BR lua (1)
+.br
+The documentation at lua.org.
+.SH DIAGNOSTICS
+Error messages should be self explanatory.
+.SH AUTHORS
+R. Ierusalimschy,
+L. H. de Figueiredo,
+W. Celes
+.\" EOF
diff --git a/test/external/lua-5.4.0/doc/manual.css b/test/external/lua-5.4.0/doc/manual.css
new file mode 100644
index 0000000..aa0e677
--- /dev/null
+++ b/test/external/lua-5.4.0/doc/manual.css
@@ -0,0 +1,21 @@
+h3 code {
+	font-family: inherit ;
+	font-size: inherit ;
+}
+
+pre, code {
+	font-size: 12pt ;
+}
+
+span.apii {
+	color: gray ;
+	float: right ;
+	font-family: inherit ;
+	font-style: normal ;
+	font-size: small ;
+}
+
+h2:before {
+	content: "" ;
+	padding-right: 0em ;
+}
diff --git a/test/external/lua-5.4.0/doc/manual.html b/test/external/lua-5.4.0/doc/manual.html
new file mode 100644
index 0000000..257f490
--- /dev/null
+++ b/test/external/lua-5.4.0/doc/manual.html
@@ -0,0 +1,11896 @@
+<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
+<HTML>
+<HEAD>
+<TITLE>Lua 5.4 Reference Manual</TITLE>
+<LINK REL="stylesheet" TYPE="text/css" HREF="lua.css">
+<LINK REL="stylesheet" TYPE="text/css" HREF="manual.css">
+<META HTTP-EQUIV="content-type" CONTENT="text/html; charset=iso-8859-1">
+</HEAD>
+
+<BODY>
+
+<H1>
+<A HREF="http://www.lua.org/"><IMG SRC="logo.gif" ALT="Lua"></A>
+Lua 5.4 Reference Manual
+</H1>
+
+<P>
+by Roberto Ierusalimschy, Luiz Henrique de Figueiredo, Waldemar Celes
+
+<P>
+<SMALL>
+Copyright &copy; 2020 Lua.org, PUC-Rio.
+Freely available under the terms of the
+<a href="http://www.lua.org/license.html">Lua license</a>.
+</SMALL>
+
+<DIV CLASS="menubar">
+<A HREF="contents.html#contents">contents</A>
+&middot;
+<A HREF="contents.html#index">index</A>
+&middot;
+<A HREF="http://www.lua.org/manual/">other versions</A>
+</DIV>
+
+<!-- ====================================================================== -->
+<p>
+
+<!-- $Id: manual.of $ -->
+
+
+
+
+<h1>1 &ndash; <a name="1">Introduction</a></h1>
+
+<p>
+Lua is a powerful, efficient, lightweight, embeddable scripting language.
+It supports procedural programming,
+object-oriented programming, functional programming,
+data-driven programming, and data description.
+
+
+<p>
+Lua combines simple procedural syntax with powerful data description
+constructs based on associative arrays and extensible semantics.
+Lua is dynamically typed,
+runs by interpreting bytecode with a register-based
+virtual machine,
+and has automatic memory management with
+a generational garbage collection,
+making it ideal for configuration, scripting,
+and rapid prototyping.
+
+
+<p>
+Lua is implemented as a library, written in <em>clean C</em>,
+the common subset of Standard&nbsp;C and C++.
+The Lua distribution includes a host program called <code>lua</code>,
+which uses the Lua library to offer a complete,
+standalone Lua interpreter,
+for interactive or batch use.
+Lua is intended to be used both as a powerful, lightweight,
+embeddable scripting language for any program that needs one,
+and as a powerful but lightweight and efficient stand-alone language.
+
+
+<p>
+As an extension language, Lua has no notion of a "main" program:
+it works <em>embedded</em> in a host client,
+called the <em>embedding program</em> or simply the <em>host</em>.
+(Frequently, this host is the stand-alone <code>lua</code> program.)
+The host program can invoke functions to execute a piece of Lua code,
+can write and read Lua variables,
+and can register C&nbsp;functions to be called by Lua code.
+Through the use of C&nbsp;functions, Lua can be augmented to cope with
+a wide range of different domains,
+thus creating customized programming languages sharing a syntactical framework.
+
+
+<p>
+Lua is free software,
+and is provided as usual with no guarantees,
+as stated in its license.
+The implementation described in this manual is available
+at Lua's official web site, <code>www.lua.org</code>.
+
+
+<p>
+Like any other reference manual,
+this document is dry in places.
+For a discussion of the decisions behind the design of Lua,
+see the technical papers available at Lua's web site.
+For a detailed introduction to programming in Lua,
+see Roberto's book, <em>Programming in Lua</em>.
+
+
+
+<h1>2 &ndash; <a name="2">Basic Concepts</a></h1>
+
+
+
+<p>
+This section describes the basic concepts of the language.
+
+
+
+
+
+<h2>2.1 &ndash; <a name="2.1">Values and Types</a></h2>
+
+<p>
+Lua is a dynamically typed language.
+This means that
+variables do not have types; only values do.
+There are no type definitions in the language.
+All values carry their own type.
+
+
+<p>
+All values in Lua are first-class values.
+This means that all values can be stored in variables,
+passed as arguments to other functions, and returned as results.
+
+
+<p>
+There are eight basic types in Lua:
+<em>nil</em>, <em>boolean</em>, <em>number</em>,
+<em>string</em>, <em>function</em>, <em>userdata</em>,
+<em>thread</em>, and <em>table</em>.
+The type <em>nil</em> has one single value, <b>nil</b>,
+whose main property is to be different from any other value;
+it often represents the absence of a useful value.
+The type <em>boolean</em> has two values, <b>false</b> and <b>true</b>.
+Both <b>nil</b> and <b>false</b> make a condition false;
+they are collectively called <em>false values</em>.
+Any other value makes a condition true.
+
+
+<p>
+The type <em>number</em> represents both
+integer numbers and real (floating-point) numbers,
+using two subtypes: <em>integer</em> and <em>float</em>.
+Standard Lua uses 64-bit integers and double-precision (64-bit) floats,
+but you can also compile Lua so that it
+uses 32-bit integers and/or single-precision (32-bit) floats.
+The option with 32 bits for both integers and floats
+is particularly attractive
+for small machines and embedded systems.
+(See macro <code>LUA_32BITS</code> in file <code>luaconf.h</code>.)
+
+
+<p>
+Unless stated otherwise,
+any overflow when manipulating integer values <em>wrap around</em>,
+according to the usual rules of two-complement arithmetic.
+(In other words,
+the actual result is the unique representable integer
+that is equal modulo <em>2<sup>n</sup></em> to the mathematical result,
+where <em>n</em> is the number of bits of the integer type.)
+
+
+<p>
+Lua has explicit rules about when each subtype is used,
+but it also converts between them automatically as needed (see <a href="#3.4.3">&sect;3.4.3</a>).
+Therefore,
+the programmer may choose to mostly ignore the difference
+between integers and floats
+or to assume complete control over the representation of each number.
+
+
+<p>
+The type <em>string</em> represents immutable sequences of bytes.
+
+Lua is 8-bit clean:
+strings can contain any 8-bit value,
+including embedded zeros ('<code>\0</code>').
+Lua is also encoding-agnostic;
+it makes no assumptions about the contents of a string.
+The length of any string in Lua must fit in a Lua integer.
+
+
+<p>
+Lua can call (and manipulate) functions written in Lua and
+functions written in C (see <a href="#3.4.10">&sect;3.4.10</a>).
+Both are represented by the type <em>function</em>.
+
+
+<p>
+The type <em>userdata</em> is provided to allow arbitrary C&nbsp;data to
+be stored in Lua variables.
+A userdata value represents a block of raw memory.
+There are two kinds of userdata:
+<em>full userdata</em>,
+which is an object with a block of memory managed by Lua,
+and <em>light userdata</em>,
+which is simply a C&nbsp;pointer value.
+Userdata has no predefined operations in Lua,
+except assignment and identity test.
+By using <em>metatables</em>,
+the programmer can define operations for full userdata values
+(see <a href="#2.4">&sect;2.4</a>).
+Userdata values cannot be created or modified in Lua,
+only through the C&nbsp;API.
+This guarantees the integrity of data owned by
+the host program and C&nbsp;libraries.
+
+
+<p>
+The type <em>thread</em> represents independent threads of execution
+and it is used to implement coroutines (see <a href="#2.6">&sect;2.6</a>).
+Lua threads are not related to operating-system threads.
+Lua supports coroutines on all systems,
+even those that do not support threads natively.
+
+
+<p>
+The type <em>table</em> implements associative arrays,
+that is, arrays that can have as indices not only numbers,
+but any Lua value except <b>nil</b> and NaN.
+(<em>Not a Number</em> is a special floating-point value
+used by the IEEE 754 standard to represent
+undefined numerical results, such as <code>0/0</code>.)
+Tables can be <em>heterogeneous</em>;
+that is, they can contain values of all types (except <b>nil</b>).
+Any key associated to the value <b>nil</b> is not considered part of the table.
+Conversely, any key that is not part of a table has
+an associated value <b>nil</b>.
+
+
+<p>
+Tables are the sole data-structuring mechanism in Lua;
+they can be used to represent ordinary arrays, lists,
+symbol tables, sets, records, graphs, trees, etc.
+To represent records, Lua uses the field name as an index.
+The language supports this representation by
+providing <code>a.name</code> as syntactic sugar for <code>a["name"]</code>.
+There are several convenient ways to create tables in Lua
+(see <a href="#3.4.9">&sect;3.4.9</a>).
+
+
+<p>
+Like indices,
+the values of table fields can be of any type.
+In particular,
+because functions are first-class values,
+table fields can contain functions.
+Thus tables can also carry <em>methods</em> (see <a href="#3.4.11">&sect;3.4.11</a>).
+
+
+<p>
+The indexing of tables follows
+the definition of raw equality in the language.
+The expressions <code>a[i]</code> and <code>a[j]</code>
+denote the same table element
+if and only if <code>i</code> and <code>j</code> are raw equal
+(that is, equal without metamethods).
+In particular, floats with integral values
+are equal to their respective integers
+(e.g., <code>1.0 == 1</code>).
+To avoid ambiguities,
+any float used as a key that is equal to an integer
+is converted to that integer.
+For instance, if you write <code>a[2.0] = true</code>,
+the actual key inserted into the table will be the integer <code>2</code>.
+
+
+<p>
+Tables, functions, threads, and (full) userdata values are <em>objects</em>:
+variables do not actually <em>contain</em> these values,
+only <em>references</em> to them.
+Assignment, parameter passing, and function returns
+always manipulate references to such values;
+these operations do not imply any kind of copy.
+
+
+<p>
+The library function <a href="#pdf-type"><code>type</code></a> returns a string describing the type
+of a given value (see <a href="#pdf-type"><code>type</code></a>).
+
+
+
+
+
+<h2>2.2 &ndash; <a name="2.2">Environments and the Global Environment</a></h2>
+
+<p>
+As we will discuss further in <a href="#3.2">&sect;3.2</a> and <a href="#3.3.3">&sect;3.3.3</a>,
+any reference to a free name
+(that is, a name not bound to any declaration) <code>var</code>
+is syntactically translated to <code>_ENV.var</code>.
+Moreover, every chunk is compiled in the scope of
+an external local variable named <code>_ENV</code> (see <a href="#3.3.2">&sect;3.3.2</a>),
+so <code>_ENV</code> itself is never a free name in a chunk.
+
+
+<p>
+Despite the existence of this external <code>_ENV</code> variable and
+the translation of free names,
+<code>_ENV</code> is a completely regular name.
+In particular,
+you can define new variables and parameters with that name.
+Each reference to a free name uses the <code>_ENV</code> that is
+visible at that point in the program,
+following the usual visibility rules of Lua (see <a href="#3.5">&sect;3.5</a>).
+
+
+<p>
+Any table used as the value of <code>_ENV</code> is called an <em>environment</em>.
+
+
+<p>
+Lua keeps a distinguished environment called the <em>global environment</em>.
+This value is kept at a special index in the C registry (see <a href="#4.3">&sect;4.3</a>).
+In Lua, the global variable <a href="#pdf-_G"><code>_G</code></a> is initialized with this same value.
+(<a href="#pdf-_G"><code>_G</code></a> is never used internally,
+so changing its value will affect only your own code.)
+
+
+<p>
+When Lua loads a chunk,
+the default value for its <code>_ENV</code> variable
+is the global environment (see <a href="#pdf-load"><code>load</code></a>).
+Therefore, by default,
+free names in Lua code refer to entries in the global environment
+and, therefore, they are also called <em>global variables</em>.
+Moreover, all standard libraries are loaded in the global environment
+and some functions there operate on that environment.
+You can use <a href="#pdf-load"><code>load</code></a> (or <a href="#pdf-loadfile"><code>loadfile</code></a>)
+to load a chunk with a different environment.
+(In C, you have to load the chunk and then change the value
+of its first upvalue; see <a href="#lua_setupvalue"><code>lua_setupvalue</code></a>.)
+
+
+
+
+
+<h2>2.3 &ndash; <a name="2.3">Error Handling</a></h2>
+
+<p>
+Several operations in Lua can <em>raise</em> an error.
+An error interrupts the normal flow of the program,
+which can continue by <em>catching</em> the error.
+
+
+<p>
+Lua code can explicitly raise an error by calling the
+<a href="#pdf-error"><code>error</code></a> function.
+(This function never returns.)
+
+
+<p>
+To catch errors in Lua,
+you can do a <em>protected call</em>,
+using <a href="#pdf-pcall"><code>pcall</code></a> (or <a href="#pdf-xpcall"><code>xpcall</code></a>).
+The function <a href="#pdf-pcall"><code>pcall</code></a> calls a given function in <em>protected mode</em>.
+Any error while running the function stops its execution,
+and control returns immediately to <code>pcall</code>,
+which returns a status code.
+
+
+<p>
+Because Lua is an embedded extension language,
+Lua code starts running by a call
+from C&nbsp;code in the host program.
+(When you use Lua standalone,
+the <code>lua</code> application is the host program.)
+Usually, this call is protected;
+so, when an otherwise unprotected error occurs during
+the compilation or execution of a Lua chunk,
+control returns to the host,
+which can take appropriate measures,
+such as printing an error message.
+
+
+<p>
+Whenever there is an error,
+an <em>error object</em>
+is propagated with information about the error.
+Lua itself only generates errors whose error object is a string,
+but programs may generate errors with
+any value as the error object.
+It is up to the Lua program or its host to handle such error objects.
+For historical reasons,
+an error object is often called an <em>error message</em>,
+even though it does not have to be a string.
+
+
+<p>
+When you use <a href="#pdf-xpcall"><code>xpcall</code></a> (or <a href="#lua_pcall"><code>lua_pcall</code></a>, in C)
+you may give a <em>message handler</em>
+to be called in case of errors.
+This function is called with the original error object
+and returns a new error object.
+It is called before the error unwinds the stack,
+so that it can gather more information about the error,
+for instance by inspecting the stack and creating a stack traceback.
+This message handler is still protected by the protected call;
+so, an error inside the message handler
+will call the message handler again.
+If this loop goes on for too long,
+Lua breaks it and returns an appropriate message.
+The message handler is called only for regular runtime errors.
+It is not called for memory-allocation errors
+nor for errors while running finalizers or other message handlers.
+
+
+<p>
+Lua also offers a system of <em>warnings</em> (see <a href="#pdf-warn"><code>warn</code></a>).
+Unlike errors, warnings do not interfere
+in any way with program execution.
+They typically only generate a message to the user,
+although this behavior can be adapted from C (see <a href="#lua_setwarnf"><code>lua_setwarnf</code></a>).
+
+
+
+
+
+<h2>2.4 &ndash; <a name="2.4">Metatables and Metamethods</a></h2>
+
+<p>
+Every value in Lua can have a <em>metatable</em>.
+This <em>metatable</em> is an ordinary Lua table
+that defines the behavior of the original value
+under certain events.
+You can change several aspects of the behavior
+of a value by setting specific fields in its metatable.
+For instance, when a non-numeric value is the operand of an addition,
+Lua checks for a function in the field "<code>__add</code>" of the value's metatable.
+If it finds one,
+Lua calls this function to perform the addition.
+
+
+<p>
+The key for each event in a metatable is a string
+with the event name prefixed by two underscores;
+the corresponding value is called a <em>metavalue</em>.
+For most events, the metavalue must be a function,
+which is then called a <em>metamethod</em>.
+In the previous example, the key is the string "<code>__add</code>"
+and the metamethod is the function that performs the addition.
+Unless stated otherwise,
+a metamethod may in fact be any callable value,
+which is either a function or a value with a <code>__call</code> metamethod.
+
+
+<p>
+You can query the metatable of any value
+using the <a href="#pdf-getmetatable"><code>getmetatable</code></a> function.
+Lua queries metamethods in metatables using a raw access (see <a href="#pdf-rawget"><code>rawget</code></a>).
+
+
+<p>
+You can replace the metatable of tables
+using the <a href="#pdf-setmetatable"><code>setmetatable</code></a> function.
+You cannot change the metatable of other types from Lua code,
+except by using the debug library (<a href="#6.10">&sect;6.10</a>).
+
+
+<p>
+Tables and full userdata have individual metatables,
+although multiple tables and userdata can share their metatables.
+Values of all other types share one single metatable per type;
+that is, there is one single metatable for all numbers,
+one for all strings, etc.
+By default, a value has no metatable,
+but the string library sets a metatable for the string type (see <a href="#6.4">&sect;6.4</a>).
+
+
+<p>
+A detailed list of operations controlled by metatables is given next.
+Each event is identified by its corresponding key.
+By convention, all metatable keys used by Lua are composed by
+two underscores followed by lowercase Latin letters.
+
+
+
+<ul>
+
+<li><b><code>__add</code>: </b>
+the addition (<code>+</code>) operation.
+If any operand for an addition is not a number,
+Lua will try to call a metamethod.
+It starts by checking the first operand (even if it is a number);
+if that operand does not define a metamethod for <code>__add</code>,
+then Lua will check the second operand.
+If Lua can find a metamethod,
+it calls the metamethod with the two operands as arguments,
+and the result of the call
+(adjusted to one value)
+is the result of the operation.
+Otherwise, if no metamethod is found,
+Lua raises an error.
+</li>
+
+<li><b><code>__sub</code>: </b>
+the subtraction (<code>-</code>) operation.
+Behavior similar to the addition operation.
+</li>
+
+<li><b><code>__mul</code>: </b>
+the multiplication (<code>*</code>) operation.
+Behavior similar to the addition operation.
+</li>
+
+<li><b><code>__div</code>: </b>
+the division (<code>/</code>) operation.
+Behavior similar to the addition operation.
+</li>
+
+<li><b><code>__mod</code>: </b>
+the modulo (<code>%</code>) operation.
+Behavior similar to the addition operation.
+</li>
+
+<li><b><code>__pow</code>: </b>
+the exponentiation (<code>^</code>) operation.
+Behavior similar to the addition operation.
+</li>
+
+<li><b><code>__unm</code>: </b>
+the negation (unary <code>-</code>) operation.
+Behavior similar to the addition operation.
+</li>
+
+<li><b><code>__idiv</code>: </b>
+the floor division (<code>//</code>) operation.
+Behavior similar to the addition operation.
+</li>
+
+<li><b><code>__band</code>: </b>
+the bitwise AND (<code>&amp;</code>) operation.
+Behavior similar to the addition operation,
+except that Lua will try a metamethod
+if any operand is neither an integer
+nor a float coercible to an integer (see <a href="#3.4.3">&sect;3.4.3</a>).
+</li>
+
+<li><b><code>__bor</code>: </b>
+the bitwise OR (<code>|</code>) operation.
+Behavior similar to the bitwise AND operation.
+</li>
+
+<li><b><code>__bxor</code>: </b>
+the bitwise exclusive OR (binary <code>~</code>) operation.
+Behavior similar to the bitwise AND operation.
+</li>
+
+<li><b><code>__bnot</code>: </b>
+the bitwise NOT (unary <code>~</code>) operation.
+Behavior similar to the bitwise AND operation.
+</li>
+
+<li><b><code>__shl</code>: </b>
+the bitwise left shift (<code>&lt;&lt;</code>) operation.
+Behavior similar to the bitwise AND operation.
+</li>
+
+<li><b><code>__shr</code>: </b>
+the bitwise right shift (<code>&gt;&gt;</code>) operation.
+Behavior similar to the bitwise AND operation.
+</li>
+
+<li><b><code>__concat</code>: </b>
+the concatenation (<code>..</code>) operation.
+Behavior similar to the addition operation,
+except that Lua will try a metamethod
+if any operand is neither a string nor a number
+(which is always coercible to a string).
+</li>
+
+<li><b><code>__len</code>: </b>
+the length (<code>#</code>) operation.
+If the object is not a string,
+Lua will try its metamethod.
+If there is a metamethod,
+Lua calls it with the object as argument,
+and the result of the call
+(always adjusted to one value)
+is the result of the operation.
+If there is no metamethod but the object is a table,
+then Lua uses the table length operation (see <a href="#3.4.7">&sect;3.4.7</a>).
+Otherwise, Lua raises an error.
+</li>
+
+<li><b><code>__eq</code>: </b>
+the equal (<code>==</code>) operation.
+Behavior similar to the addition operation,
+except that Lua will try a metamethod only when the values
+being compared are either both tables or both full userdata
+and they are not primitively equal.
+The result of the call is always converted to a boolean.
+</li>
+
+<li><b><code>__lt</code>: </b>
+the less than (<code>&lt;</code>) operation.
+Behavior similar to the addition operation,
+except that Lua will try a metamethod only when the values
+being compared are neither both numbers nor both strings.
+Moreover, the result of the call is always converted to a boolean.
+</li>
+
+<li><b><code>__le</code>: </b>
+the less equal (<code>&lt;=</code>) operation.
+Behavior similar to the less than operation.
+</li>
+
+<li><b><code>__index</code>: </b>
+The indexing access operation <code>table[key]</code>.
+This event happens when <code>table</code> is not a table or
+when <code>key</code> is not present in <code>table</code>.
+The metavalue is looked up in the metatable of <code>table</code>.
+
+
+<p>
+The metavalue for this event can be either a function, a table,
+or any value with an <code>__index</code> metavalue.
+If it is a function,
+it is called with <code>table</code> and <code>key</code> as arguments,
+and the result of the call
+(adjusted to one value)
+is the result of the operation.
+Otherwise,
+the final result is the result of indexing this metavalue with <code>key</code>.
+This indexing is regular, not raw,
+and therefore can trigger another <code>__index</code> metavalue.
+</li>
+
+<li><b><code>__newindex</code>: </b>
+The indexing assignment <code>table[key] = value</code>.
+Like the index event,
+this event happens when <code>table</code> is not a table or
+when <code>key</code> is not present in <code>table</code>.
+The metavalue is looked up in the metatable of <code>table</code>.
+
+
+<p>
+Like with indexing,
+the metavalue for this event can be either a function, a table,
+or any value with an <code>__newindex</code> metavalue.
+If it is a function,
+it is called with <code>table</code>, <code>key</code>, and <code>value</code> as arguments.
+Otherwise,
+Lua repeats the indexing assignment over this metavalue
+with the same key and value.
+This assignment is regular, not raw,
+and therefore can trigger another <code>__newindex</code> metavalue.
+
+
+<p>
+Whenever a <code>__newindex</code> metavalue is invoked,
+Lua does not perform the primitive assignment.
+If needed,
+the metamethod itself can call <a href="#pdf-rawset"><code>rawset</code></a>
+to do the assignment.
+</li>
+
+<li><b><code>__call</code>: </b>
+The call operation <code>func(args)</code>.
+This event happens when Lua tries to call a non-function value
+(that is, <code>func</code> is not a function).
+The metamethod is looked up in <code>func</code>.
+If present,
+the metamethod is called with <code>func</code> as its first argument,
+followed by the arguments of the original call (<code>args</code>).
+All results of the call
+are the results of the operation.
+This is the only metamethod that allows multiple results.
+</li>
+
+</ul>
+
+<p>
+In addition to the previous list,
+the interpreter also respects the following keys in metatables:
+<code>__gc</code> (see <a href="#2.5.3">&sect;2.5.3</a>),
+<code>__close</code> (see <a href="#3.3.8">&sect;3.3.8</a>),
+<code>__mode</code> (see <a href="#2.5.4">&sect;2.5.4</a>),
+and <code>__name</code>.
+(The entry <code>__name</code>,
+when it contains a string,
+may be used by <a href="#pdf-tostring"><code>tostring</code></a> and in error messages.)
+
+
+<p>
+For the unary operators (negation, length, and bitwise NOT),
+the metamethod is computed and called with a dummy second operand,
+equal to the first one.
+This extra operand is only to simplify Lua's internals
+(by making these operators behave like a binary operation)
+and may be removed in future versions.
+For most uses this extra operand is irrelevant.
+
+
+<p>
+Because metatables are regular tables,
+they can contain arbitrary fields,
+not only the event names defined above.
+Some functions in the standard library
+(e.g., <a href="#pdf-tostring"><code>tostring</code></a>)
+use other fields in metatables for their own purposes.
+
+
+<p>
+It is a good practice to add all needed metamethods to a table
+before setting it as a metatable of some object.
+In particular, the <code>__gc</code> metamethod works only when this order
+is followed (see <a href="#2.5.3">&sect;2.5.3</a>).
+It is also a good practice to set the metatable of an object
+right after its creation.
+
+
+
+
+
+<h2>2.5 &ndash; <a name="2.5">Garbage Collection</a></h2>
+
+
+
+<p>
+Lua performs automatic memory management.
+This means that
+you do not have to worry about allocating memory for new objects
+or freeing it when the objects are no longer needed.
+Lua manages memory automatically by running
+a <em>garbage collector</em> to collect all <em>dead</em> objects.
+All memory used by Lua is subject to automatic management:
+strings, tables, userdata, functions, threads, internal structures, etc.
+
+
+<p>
+An object is considered <em>dead</em>
+as soon as the collector can be sure the object
+will not be accessed again in the normal execution of the program.
+("Normal execution" here excludes finalizers,
+which can resurrect dead objects (see <a href="#2.5.3">&sect;2.5.3</a>),
+and excludes also operations using the debug library.)
+Note that the time when the collector can be sure that an object
+is dead may not coincide with the programmer's expectations.
+The only guarantees are that Lua will not collect an object
+that may still be accessed in the normal execution of the program,
+and it will eventually collect an object
+that is inaccessible from Lua.
+(Here,
+<em>inaccessible from Lua</em> means that neither a variable nor
+another live object refer to the object.)
+Because Lua has no knowledge about C&nbsp;code,
+it never collects objects accessible through the registry (see <a href="#4.3">&sect;4.3</a>),
+which includes the global environment (see <a href="#2.2">&sect;2.2</a>).
+
+
+<p>
+The garbage collector (GC) in Lua can work in two modes:
+incremental and generational.
+
+
+<p>
+The default GC mode with the default parameters
+are adequate for most uses.
+However, programs that waste a large proportion of their time
+allocating and freeing memory can benefit from other settings.
+Keep in mind that the GC behavior is non-portable
+both across platforms and across different Lua releases;
+therefore, optimal settings are also non-portable.
+
+
+<p>
+You can change the GC mode and parameters by calling
+<a href="#lua_gc"><code>lua_gc</code></a> in&nbsp;C
+or <a href="#pdf-collectgarbage"><code>collectgarbage</code></a> in Lua.
+You can also use these functions to control
+the collector directly (e.g., to stop and restart it).
+
+
+
+
+
+<h3>2.5.1 &ndash; <a name="2.5.1">Incremental Garbage Collection</a></h3>
+
+<p>
+In incremental mode,
+each GC cycle performs a mark-and-sweep collection in small steps
+interleaved with the program's execution.
+In this mode,
+the collector uses three numbers to control its garbage-collection cycles:
+the <em>garbage-collector pause</em>,
+the <em>garbage-collector step multiplier</em>,
+and the <em>garbage-collector step size</em>.
+
+
+<p>
+The garbage-collector pause
+controls how long the collector waits before starting a new cycle.
+The collector starts a new cycle when the use of memory
+hits <em>n%</em> of the use after the previous collection.
+Larger values make the collector less aggressive.
+Values equal to or less than 100 mean the collector will not wait to
+start a new cycle.
+A value of 200 means that the collector waits for the total memory in use
+to double before starting a new cycle.
+The default value is 200; the maximum value is 1000.
+
+
+<p>
+The garbage-collector step multiplier
+controls the speed of the collector relative to
+memory allocation,
+that is,
+how many elements it marks or sweeps for each
+kilobyte of memory allocated.
+Larger values make the collector more aggressive but also increase
+the size of each incremental step.
+You should not use values less than 100,
+because they make the collector too slow and
+can result in the collector never finishing a cycle.
+The default value is 100;  the maximum value is 1000.
+
+
+<p>
+The garbage-collector step size controls the
+size of each incremental step,
+specifically how many bytes the interpreter allocates
+before performing a step.
+This parameter is logarithmic:
+A value of <em>n</em> means the interpreter will allocate <em>2<sup>n</sup></em>
+bytes between steps and perform equivalent work during the step.
+A large value (e.g., 60) makes the collector a stop-the-world
+(non-incremental) collector.
+The default value is 13,
+which means steps of approximately 8&nbsp;Kbytes.
+
+
+
+
+
+<h3>2.5.2 &ndash; <a name="2.5.2">Generational Garbage Collection</a></h3>
+
+<p>
+In generational mode,
+the collector does frequent <em>minor</em> collections,
+which traverses only objects recently created.
+If after a minor collection the use of memory is still above a limit,
+the collector does a stop-the-world <em>major</em> collection,
+which traverses all objects.
+The generational mode uses two parameters:
+the <em>minor multiplier</em> and the <em>the major multiplier</em>.
+
+
+<p>
+The minor multiplier controls the frequency of minor collections.
+For a minor multiplier <em>x</em>,
+a new minor collection will be done when memory
+grows <em>x%</em> larger than the memory in use after the previous major
+collection.
+For instance, for a multiplier of 20,
+the collector will do a minor collection when the use of memory
+gets 20% larger than the use after the previous major collection.
+The default value is 20; the maximum value is 200.
+
+
+<p>
+The major multiplier controls the frequency of major collections.
+For a major multiplier <em>x</em>,
+a new major collection will be done when memory
+grows <em>x%</em> larger than the memory in use after the previous major
+collection.
+For instance, for a multiplier of 100,
+the collector will do a major collection when the use of memory
+gets larger than twice the use after the previous collection.
+The default value is 100; the maximum value is 1000.
+
+
+
+
+
+<h3>2.5.3 &ndash; <a name="2.5.3">Garbage-Collection Metamethods</a></h3>
+
+<p>
+You can set garbage-collector metamethods for tables
+and, using the C&nbsp;API,
+for full userdata (see <a href="#2.4">&sect;2.4</a>).
+These metamethods, called <em>finalizers</em>,
+are called when the garbage collector detects that the
+corresponding table or userdata is dead.
+Finalizers allow you to coordinate Lua's garbage collection
+with external resource management such as closing files,
+network or database connections,
+or freeing your own memory.
+
+
+<p>
+For an object (table or userdata) to be finalized when collected,
+you must <em>mark</em> it for finalization.
+
+You mark an object for finalization when you set its metatable
+and the metatable has a field indexed by the string "<code>__gc</code>".
+Note that if you set a metatable without a <code>__gc</code> field
+and later create that field in the metatable,
+the object will not be marked for finalization.
+
+
+<p>
+When a marked object becomes dead,
+it is not collected immediately by the garbage collector.
+Instead, Lua puts it in a list.
+After the collection,
+Lua goes through that list.
+For each object in the list,
+it checks the object's <code>__gc</code> metamethod:
+If it is present,
+Lua calls it with the object as its single argument.
+
+
+<p>
+At the end of each garbage-collection cycle,
+the finalizers are called in
+the reverse order that the objects were marked for finalization,
+among those collected in that cycle;
+that is, the first finalizer to be called is the one associated
+with the object marked last in the program.
+The execution of each finalizer may occur at any point during
+the execution of the regular code.
+
+
+<p>
+Because the object being collected must still be used by the finalizer,
+that object (and other objects accessible only through it)
+must be <em>resurrected</em> by Lua.
+Usually, this resurrection is transient,
+and the object memory is freed in the next garbage-collection cycle.
+However, if the finalizer stores the object in some global place
+(e.g., a global variable),
+then the resurrection is permanent.
+Moreover, if the finalizer marks a finalizing object for finalization again,
+its finalizer will be called again in the next cycle where the
+object is dead.
+In any case,
+the object memory is freed only in a GC cycle where
+the object is dead and not marked for finalization.
+
+
+<p>
+When you close a state (see <a href="#lua_close"><code>lua_close</code></a>),
+Lua calls the finalizers of all objects marked for finalization,
+following the reverse order that they were marked.
+If any finalizer marks objects for collection during that phase,
+these marks have no effect.
+
+
+<p>
+Finalizers cannot yield.
+Except for that, they can do anything,
+such as raise errors, create new objects,
+or even run the garbage collector.
+However, because they can run in unpredictable times,
+it is good practice to restrict each finalizer
+to the minimum necessary to properly release
+its associated resource.
+
+
+<p>
+Any error while running a finalizer generates a warning;
+the error is not propagated.
+
+
+
+
+
+<h3>2.5.4 &ndash; <a name="2.5.4">Weak Tables</a></h3>
+
+<p>
+A <em>weak table</em> is a table whose elements are
+<em>weak references</em>.
+A weak reference is ignored by the garbage collector.
+In other words,
+if the only references to an object are weak references,
+then the garbage collector will collect that object.
+
+
+<p>
+A weak table can have weak keys, weak values, or both.
+A table with weak values allows the collection of its values,
+but prevents the collection of its keys.
+A table with both weak keys and weak values allows the collection of
+both keys and values.
+In any case, if either the key or the value is collected,
+the whole pair is removed from the table.
+The weakness of a table is controlled by the
+<code>__mode</code> field of its metatable.
+This metavalue, if present, must be one of the following strings:
+"<code>k</code>", for a table with weak keys;
+"<code>v</code>", for a table with weak values;
+or "<code>kv</code>", for a table with both weak keys and values.
+
+
+<p>
+A table with weak keys and strong values
+is also called an <em>ephemeron table</em>.
+In an ephemeron table,
+a value is considered reachable only if its key is reachable.
+In particular,
+if the only reference to a key comes through its value,
+the pair is removed.
+
+
+<p>
+Any change in the weakness of a table may take effect only
+at the next collect cycle.
+In particular, if you change the weakness to a stronger mode,
+Lua may still collect some items from that table
+before the change takes effect.
+
+
+<p>
+Only objects that have an explicit construction
+are removed from weak tables.
+Values, such as numbers and light C&nbsp;functions,
+are not subject to garbage collection,
+and therefore are not removed from weak tables
+(unless their associated values are collected).
+Although strings are subject to garbage collection,
+they do not have an explicit construction and
+their equality is by value;
+they behave more like values than like objects.
+Therefore, they are not removed from weak tables.
+
+
+<p>
+Resurrected objects
+(that is, objects being finalized
+and objects accessible only through objects being finalized)
+have a special behavior in weak tables.
+They are removed from weak values before running their finalizers,
+but are removed from weak keys only in the next collection
+after running their finalizers, when such objects are actually freed.
+This behavior allows the finalizer to access properties
+associated with the object through weak tables.
+
+
+<p>
+If a weak table is among the resurrected objects in a collection cycle,
+it may not be properly cleared until the next cycle.
+
+
+
+
+
+
+
+<h2>2.6 &ndash; <a name="2.6">Coroutines</a></h2>
+
+<p>
+Lua supports coroutines,
+also called <em>collaborative multithreading</em>.
+A coroutine in Lua represents an independent thread of execution.
+Unlike threads in multithread systems, however,
+a coroutine only suspends its execution by explicitly calling
+a yield function.
+
+
+<p>
+You create a coroutine by calling <a href="#pdf-coroutine.create"><code>coroutine.create</code></a>.
+Its sole argument is a function
+that is the main function of the coroutine.
+The <code>create</code> function only creates a new coroutine and
+returns a handle to it (an object of type <em>thread</em>);
+it does not start the coroutine.
+
+
+<p>
+You execute a coroutine by calling <a href="#pdf-coroutine.resume"><code>coroutine.resume</code></a>.
+When you first call <a href="#pdf-coroutine.resume"><code>coroutine.resume</code></a>,
+passing as its first argument
+a thread returned by <a href="#pdf-coroutine.create"><code>coroutine.create</code></a>,
+the coroutine starts its execution by
+calling its main function.
+Extra arguments passed to <a href="#pdf-coroutine.resume"><code>coroutine.resume</code></a> are passed
+as arguments to that function.
+After the coroutine starts running,
+it runs until it terminates or <em>yields</em>.
+
+
+<p>
+A coroutine can terminate its execution in two ways:
+normally, when its main function returns
+(explicitly or implicitly, after the last instruction);
+and abnormally, if there is an unprotected error.
+In case of normal termination,
+<a href="#pdf-coroutine.resume"><code>coroutine.resume</code></a> returns <b>true</b>,
+plus any values returned by the coroutine main function.
+In case of errors, <a href="#pdf-coroutine.resume"><code>coroutine.resume</code></a> returns <b>false</b>
+plus the error object.
+In this case, the coroutine does not unwind its stack,
+so that it is possible to inspect it after the error
+with the debug API.
+
+
+<p>
+A coroutine yields by calling <a href="#pdf-coroutine.yield"><code>coroutine.yield</code></a>.
+When a coroutine yields,
+the corresponding <a href="#pdf-coroutine.resume"><code>coroutine.resume</code></a> returns immediately,
+even if the yield happens inside nested function calls
+(that is, not in the main function,
+but in a function directly or indirectly called by the main function).
+In the case of a yield, <a href="#pdf-coroutine.resume"><code>coroutine.resume</code></a> also returns <b>true</b>,
+plus any values passed to <a href="#pdf-coroutine.yield"><code>coroutine.yield</code></a>.
+The next time you resume the same coroutine,
+it continues its execution from the point where it yielded,
+with the call to <a href="#pdf-coroutine.yield"><code>coroutine.yield</code></a> returning any extra
+arguments passed to <a href="#pdf-coroutine.resume"><code>coroutine.resume</code></a>.
+
+
+<p>
+Like <a href="#pdf-coroutine.create"><code>coroutine.create</code></a>,
+the <a href="#pdf-coroutine.wrap"><code>coroutine.wrap</code></a> function also creates a coroutine,
+but instead of returning the coroutine itself,
+it returns a function that, when called, resumes the coroutine.
+Any arguments passed to this function
+go as extra arguments to <a href="#pdf-coroutine.resume"><code>coroutine.resume</code></a>.
+<a href="#pdf-coroutine.wrap"><code>coroutine.wrap</code></a> returns all the values returned by <a href="#pdf-coroutine.resume"><code>coroutine.resume</code></a>,
+except the first one (the boolean error code).
+Unlike <a href="#pdf-coroutine.resume"><code>coroutine.resume</code></a>,
+the function created by <a href="#pdf-coroutine.wrap"><code>coroutine.wrap</code></a>
+propagates any error to the caller.
+In this case,
+the function also closes the coroutine (see <a href="#pdf-coroutine.close"><code>coroutine.close</code></a>).
+
+
+<p>
+As an example of how coroutines work,
+consider the following code:
+
+<pre>
+     function foo (a)
+       print("foo", a)
+       return coroutine.yield(2*a)
+     end
+     
+     co = coroutine.create(function (a,b)
+           print("co-body", a, b)
+           local r = foo(a+1)
+           print("co-body", r)
+           local r, s = coroutine.yield(a+b, a-b)
+           print("co-body", r, s)
+           return b, "end"
+     end)
+     
+     print("main", coroutine.resume(co, 1, 10))
+     print("main", coroutine.resume(co, "r"))
+     print("main", coroutine.resume(co, "x", "y"))
+     print("main", coroutine.resume(co, "x", "y"))
+</pre><p>
+When you run it, it produces the following output:
+
+<pre>
+     co-body 1       10
+     foo     2
+     main    true    4
+     co-body r
+     main    true    11      -9
+     co-body x       y
+     main    true    10      end
+     main    false   cannot resume dead coroutine
+</pre>
+
+<p>
+You can also create and manipulate coroutines through the C API:
+see functions <a href="#lua_newthread"><code>lua_newthread</code></a>, <a href="#lua_resume"><code>lua_resume</code></a>,
+and <a href="#lua_yield"><code>lua_yield</code></a>.
+
+
+
+
+
+<h1>3 &ndash; <a name="3">The Language</a></h1>
+
+
+
+<p>
+This section describes the lexis, the syntax, and the semantics of Lua.
+In other words,
+this section describes
+which tokens are valid,
+how they can be combined,
+and what their combinations mean.
+
+
+<p>
+Language constructs will be explained using the usual extended BNF notation,
+in which
+{<em>a</em>}&nbsp;means&nbsp;0 or more <em>a</em>'s, and
+[<em>a</em>]&nbsp;means an optional <em>a</em>.
+Non-terminals are shown like non-terminal,
+keywords are shown like <b>kword</b>,
+and other terminal symbols are shown like &lsquo;<b>=</b>&rsquo;.
+The complete syntax of Lua can be found in <a href="#9">&sect;9</a>
+at the end of this manual.
+
+
+
+
+
+<h2>3.1 &ndash; <a name="3.1">Lexical Conventions</a></h2>
+
+<p>
+Lua is a free-form language.
+It ignores spaces and comments between lexical elements (tokens),
+except as delimiters between two tokens.
+In source code,
+Lua recognizes as spaces the standard ASCII whitespace
+characters space, form feed, newline,
+carriage return, horizontal tab, and vertical tab.
+
+
+<p>
+<em>Names</em>
+(also called <em>identifiers</em>)
+in Lua can be any string of Latin letters,
+Arabic-Indic digits, and underscores,
+not beginning with a digit and
+not being a reserved word.
+Identifiers are used to name variables, table fields, and labels.
+
+
+<p>
+The following <em>keywords</em> are reserved
+and cannot be used as names:
+
+
+<pre>
+     and       break     do        else      elseif    end
+     false     for       function  goto      if        in
+     local     nil       not       or        repeat    return
+     then      true      until     while
+</pre>
+
+<p>
+Lua is a case-sensitive language:
+<code>and</code> is a reserved word, but <code>And</code> and <code>AND</code>
+are two different, valid names.
+As a convention,
+programs should avoid creating
+names that start with an underscore followed by
+one or more uppercase letters (such as <a href="#pdf-_VERSION"><code>_VERSION</code></a>).
+
+
+<p>
+The following strings denote other tokens:
+
+<pre>
+     +     -     *     /     %     ^     #
+     &amp;     ~     |     &lt;&lt;    &gt;&gt;    //
+     ==    ~=    &lt;=    &gt;=    &lt;     &gt;     =
+     (     )     {     }     [     ]     ::
+     ;     :     ,     .     ..    ...
+</pre>
+
+<p>
+A <em>short literal string</em>
+can be delimited by matching single or double quotes,
+and can contain the following C-like escape sequences:
+'<code>\a</code>' (bell),
+'<code>\b</code>' (backspace),
+'<code>\f</code>' (form feed),
+'<code>\n</code>' (newline),
+'<code>\r</code>' (carriage return),
+'<code>\t</code>' (horizontal tab),
+'<code>\v</code>' (vertical tab),
+'<code>\\</code>' (backslash),
+'<code>\"</code>' (quotation mark [double quote]),
+and '<code>\'</code>' (apostrophe [single quote]).
+A backslash followed by a line break
+results in a newline in the string.
+The escape sequence '<code>\z</code>' skips the following span
+of whitespace characters,
+including line breaks;
+it is particularly useful to break and indent a long literal string
+into multiple lines without adding the newlines and spaces
+into the string contents.
+A short literal string cannot contain unescaped line breaks
+nor escapes not forming a valid escape sequence.
+
+
+<p>
+We can specify any byte in a short literal string,
+including embedded zeros,
+by its numeric value.
+This can be done
+with the escape sequence <code>\x<em>XX</em></code>,
+where <em>XX</em> is a sequence of exactly two hexadecimal digits,
+or with the escape sequence <code>\<em>ddd</em></code>,
+where <em>ddd</em> is a sequence of up to three decimal digits.
+(Note that if a decimal escape sequence is to be followed by a digit,
+it must be expressed using exactly three digits.)
+
+
+<p>
+The UTF-8 encoding of a Unicode character
+can be inserted in a literal string with
+the escape sequence <code>\u{<em>XXX</em>}</code>
+(with mandatory enclosing braces),
+where <em>XXX</em> is a sequence of one or more hexadecimal digits
+representing the character code point.
+This code point can be any value less than <em>2<sup>31</sup></em>.
+(Lua uses the original UTF-8 specification here,
+which is not restricted to valid Unicode code points.)
+
+
+<p>
+Literal strings can also be defined using a long format
+enclosed by <em>long brackets</em>.
+We define an <em>opening long bracket of level <em>n</em></em> as an opening
+square bracket followed by <em>n</em> equal signs followed by another
+opening square bracket.
+So, an opening long bracket of level&nbsp;0 is written as <code>[[</code>, 
+an opening long bracket of level&nbsp;1 is written as <code>[=[</code>, 
+and so on.
+A <em>closing long bracket</em> is defined similarly;
+for instance,
+a closing long bracket of level&nbsp;4 is written as  <code>]====]</code>.
+A <em>long literal</em> starts with an opening long bracket of any level and
+ends at the first closing long bracket of the same level.
+It can contain any text except a closing bracket of the same level.
+Literals in this bracketed form can run for several lines,
+do not interpret any escape sequences,
+and ignore long brackets of any other level.
+Any kind of end-of-line sequence
+(carriage return, newline, carriage return followed by newline,
+or newline followed by carriage return)
+is converted to a simple newline.
+When the opening long bracket is immediately followed by a newline,
+the newline is not included in the string.
+
+
+<p>
+As an example, in a system using ASCII
+(in which '<code>a</code>' is coded as&nbsp;97,
+newline is coded as&nbsp;10, and '<code>1</code>' is coded as&nbsp;49),
+the five literal strings below denote the same string:
+
+<pre>
+     a = 'alo\n123"'
+     a = "alo\n123\""
+     a = '\97lo\10\04923"'
+     a = [[alo
+     123"]]
+     a = [==[
+     alo
+     123"]==]
+</pre>
+
+<p>
+Any byte in a literal string not
+explicitly affected by the previous rules represents itself.
+However, Lua opens files for parsing in text mode,
+and the system's file functions may have problems with
+some control characters.
+So, it is safer to represent
+binary data as a quoted literal with
+explicit escape sequences for the non-text characters.
+
+
+<p>
+A <em>numeric constant</em> (or <em>numeral</em>)
+can be written with an optional fractional part
+and an optional decimal exponent,
+marked by a letter '<code>e</code>' or '<code>E</code>'.
+Lua also accepts hexadecimal constants,
+which start with <code>0x</code> or <code>0X</code>.
+Hexadecimal constants also accept an optional fractional part
+plus an optional binary exponent,
+marked by a letter '<code>p</code>' or '<code>P</code>'.
+
+
+<p>
+A numeric constant with a radix point or an exponent
+denotes a float;
+otherwise,
+if its value fits in an integer or it is a hexadecimal constant,
+it denotes an integer;
+otherwise (that is, a decimal integer numeral that overflows),
+it denotes a float.
+Hexadecimal numerals with neither a radix point nor an exponent
+always denote an integer value;
+if the value overflows, it <em>wraps around</em>
+to fit into a valid integer.
+
+
+<p>
+Examples of valid integer constants are
+
+<pre>
+     3   345   0xff   0xBEBADA
+</pre><p>
+Examples of valid float constants are
+
+<pre>
+     3.0     3.1416     314.16e-2     0.31416E1     34e1
+     0x0.1E  0xA23p-4   0X1.921FB54442D18P+1
+</pre>
+
+<p>
+A <em>comment</em> starts with a double hyphen (<code>--</code>)
+anywhere outside a string.
+If the text immediately after <code>--</code> is not an opening long bracket,
+the comment is a <em>short comment</em>,
+which runs until the end of the line.
+Otherwise, it is a <em>long comment</em>,
+which runs until the corresponding closing long bracket.
+
+
+
+
+
+<h2>3.2 &ndash; <a name="3.2">Variables</a></h2>
+
+<p>
+Variables are places that store values.
+There are three kinds of variables in Lua:
+global variables, local variables, and table fields.
+
+
+<p>
+A single name can denote a global variable or a local variable
+(or a function's formal parameter,
+which is a particular kind of local variable):
+
+<pre>
+	var ::= Name
+</pre><p>
+Name denotes identifiers (see <a href="#3.1">&sect;3.1</a>).
+
+
+<p>
+Any variable name is assumed to be global unless explicitly declared
+as a local (see <a href="#3.3.7">&sect;3.3.7</a>).
+Local variables are <em>lexically scoped</em>:
+local variables can be freely accessed by functions
+defined inside their scope (see <a href="#3.5">&sect;3.5</a>).
+
+
+<p>
+Before the first assignment to a variable, its value is <b>nil</b>.
+
+
+<p>
+Square brackets are used to index a table:
+
+<pre>
+	var ::= prefixexp &lsquo;<b>[</b>&rsquo; exp &lsquo;<b>]</b>&rsquo;
+</pre><p>
+The meaning of accesses to table fields can be changed via metatables
+(see <a href="#2.4">&sect;2.4</a>).
+
+
+<p>
+The syntax <code>var.Name</code> is just syntactic sugar for
+<code>var["Name"]</code>:
+
+<pre>
+	var ::= prefixexp &lsquo;<b>.</b>&rsquo; Name
+</pre>
+
+<p>
+An access to a global variable <code>x</code>
+is equivalent to <code>_ENV.x</code>.
+Due to the way that chunks are compiled,
+the variable <code>_ENV</code> itself is never global (see <a href="#2.2">&sect;2.2</a>).
+
+
+
+
+
+<h2>3.3 &ndash; <a name="3.3">Statements</a></h2>
+
+
+
+<p>
+Lua supports an almost conventional set of statements,
+similar to those in other conventional languages.
+This set includes
+blocks, assignments, control structures, function calls,
+and variable declarations.
+
+
+
+
+
+<h3>3.3.1 &ndash; <a name="3.3.1">Blocks</a></h3>
+
+<p>
+A block is a list of statements,
+which are executed sequentially:
+
+<pre>
+	block ::= {stat}
+</pre><p>
+Lua has <em>empty statements</em>
+that allow you to separate statements with semicolons,
+start a block with a semicolon
+or write two semicolons in sequence:
+
+<pre>
+	stat ::= &lsquo;<b>;</b>&rsquo;
+</pre>
+
+<p>
+Both function calls and assignments
+can start with an open parenthesis.
+This possibility leads to an ambiguity in Lua's grammar.
+Consider the following fragment:
+
+<pre>
+     a = b + c
+     (print or io.write)('done')
+</pre><p>
+The grammar could see this fragment in two ways:
+
+<pre>
+     a = b + c(print or io.write)('done')
+     
+     a = b + c; (print or io.write)('done')
+</pre><p>
+The current parser always sees such constructions
+in the first way,
+interpreting the open parenthesis
+as the start of the arguments to a call.
+To avoid this ambiguity,
+it is a good practice to always precede with a semicolon
+statements that start with a parenthesis:
+
+<pre>
+     ;(print or io.write)('done')
+</pre>
+
+<p>
+A block can be explicitly delimited to produce a single statement:
+
+<pre>
+	stat ::= <b>do</b> block <b>end</b>
+</pre><p>
+Explicit blocks are useful
+to control the scope of variable declarations.
+Explicit blocks are also sometimes used to
+add a <b>return</b> statement in the middle
+of another block (see <a href="#3.3.4">&sect;3.3.4</a>).
+
+
+
+
+
+<h3>3.3.2 &ndash; <a name="3.3.2">Chunks</a></h3>
+
+<p>
+The unit of compilation of Lua is called a <em>chunk</em>.
+Syntactically,
+a chunk is simply a block:
+
+<pre>
+	chunk ::= block
+</pre>
+
+<p>
+Lua handles a chunk as the body of an anonymous function
+with a variable number of arguments
+(see <a href="#3.4.11">&sect;3.4.11</a>).
+As such, chunks can define local variables,
+receive arguments, and return values.
+Moreover, such anonymous function is compiled as in the
+scope of an external local variable called <code>_ENV</code> (see <a href="#2.2">&sect;2.2</a>).
+The resulting function always has <code>_ENV</code> as its only external variable,
+even if it does not use that variable.
+
+
+<p>
+A chunk can be stored in a file or in a string inside the host program.
+To execute a chunk,
+Lua first <em>loads</em> it,
+precompiling the chunk's code into instructions for a virtual machine,
+and then Lua executes the compiled code
+with an interpreter for the virtual machine.
+
+
+<p>
+Chunks can also be precompiled into binary form;
+see the program <code>luac</code> and the function <a href="#pdf-string.dump"><code>string.dump</code></a> for details.
+Programs in source and compiled forms are interchangeable;
+Lua automatically detects the file type and acts accordingly (see <a href="#pdf-load"><code>load</code></a>).
+
+
+
+
+
+<h3>3.3.3 &ndash; <a name="3.3.3">Assignment</a></h3>
+
+<p>
+Lua allows multiple assignments.
+Therefore, the syntax for assignment
+defines a list of variables on the left side
+and a list of expressions on the right side.
+The elements in both lists are separated by commas:
+
+<pre>
+	stat ::= varlist &lsquo;<b>=</b>&rsquo; explist
+	varlist ::= var {&lsquo;<b>,</b>&rsquo; var}
+	explist ::= exp {&lsquo;<b>,</b>&rsquo; exp}
+</pre><p>
+Expressions are discussed in <a href="#3.4">&sect;3.4</a>.
+
+
+<p>
+Before the assignment,
+the list of values is <em>adjusted</em> to the length of
+the list of variables.
+If there are more values than needed,
+the excess values are thrown away.
+If there are fewer values than needed,
+the list is extended with <b>nil</b>'s.
+If the list of expressions ends with a function call,
+then all values returned by that call enter the list of values,
+before the adjustment
+(except when the call is enclosed in parentheses; see <a href="#3.4">&sect;3.4</a>).
+
+
+<p>
+The assignment statement first evaluates all its expressions
+and only then the assignments are performed.
+Thus the code
+
+<pre>
+     i = 3
+     i, a[i] = i+1, 20
+</pre><p>
+sets <code>a[3]</code> to 20, without affecting <code>a[4]</code>
+because the <code>i</code> in <code>a[i]</code> is evaluated (to 3)
+before it is assigned&nbsp;4.
+Similarly, the line
+
+<pre>
+     x, y = y, x
+</pre><p>
+exchanges the values of <code>x</code> and <code>y</code>,
+and
+
+<pre>
+     x, y, z = y, z, x
+</pre><p>
+cyclically permutes the values of <code>x</code>, <code>y</code>, and <code>z</code>.
+
+
+<p>
+An assignment to a global name <code>x = val</code>
+is equivalent to the assignment
+<code>_ENV.x = val</code> (see <a href="#2.2">&sect;2.2</a>).
+
+
+<p>
+The meaning of assignments to table fields and
+global variables (which are actually table fields, too)
+can be changed via metatables (see <a href="#2.4">&sect;2.4</a>).
+
+
+
+
+
+<h3>3.3.4 &ndash; <a name="3.3.4">Control Structures</a></h3><p>
+The control structures
+<b>if</b>, <b>while</b>, and <b>repeat</b> have the usual meaning and
+familiar syntax:
+
+
+
+
+<pre>
+	stat ::= <b>while</b> exp <b>do</b> block <b>end</b>
+	stat ::= <b>repeat</b> block <b>until</b> exp
+	stat ::= <b>if</b> exp <b>then</b> block {<b>elseif</b> exp <b>then</b> block} [<b>else</b> block] <b>end</b>
+</pre><p>
+Lua also has a <b>for</b> statement, in two flavors (see <a href="#3.3.5">&sect;3.3.5</a>).
+
+
+<p>
+The condition expression of a
+control structure can return any value.
+Both <b>false</b> and <b>nil</b> test false.
+All values different from <b>nil</b> and <b>false</b> test true.
+In particular, the number 0 and the empty string also test true.
+
+
+<p>
+In the <b>repeat</b>&ndash;<b>until</b> loop,
+the inner block does not end at the <b>until</b> keyword,
+but only after the condition.
+So, the condition can refer to local variables
+declared inside the loop block.
+
+
+<p>
+The <b>goto</b> statement transfers the program control to a label.
+For syntactical reasons,
+labels in Lua are considered statements too:
+
+
+
+<pre>
+	stat ::= <b>goto</b> Name
+	stat ::= label
+	label ::= &lsquo;<b>::</b>&rsquo; Name &lsquo;<b>::</b>&rsquo;
+</pre>
+
+<p>
+A label is visible in the entire block where it is defined,
+except inside nested functions.
+A goto may jump to any visible label as long as it does not
+enter into the scope of a local variable.
+A label should not be declared
+where a label with the same name is visible,
+even if this other label has been declared in an enclosing block.
+
+
+<p>
+Labels and empty statements are called <em>void statements</em>,
+as they perform no actions.
+
+
+<p>
+The <b>break</b> statement terminates the execution of a
+<b>while</b>, <b>repeat</b>, or <b>for</b> loop,
+skipping to the next statement after the loop:
+
+
+<pre>
+	stat ::= <b>break</b>
+</pre><p>
+A <b>break</b> ends the innermost enclosing loop.
+
+
+<p>
+The <b>return</b> statement is used to return values
+from a function or a chunk
+(which is handled as an anonymous function).
+
+Functions can return more than one value,
+so the syntax for the <b>return</b> statement is
+
+<pre>
+	stat ::= <b>return</b> [explist] [&lsquo;<b>;</b>&rsquo;]
+</pre>
+
+<p>
+The <b>return</b> statement can only be written
+as the last statement of a block.
+If it is necessary to <b>return</b> in the middle of a block,
+then an explicit inner block can be used,
+as in the idiom <code>do return end</code>,
+because now <b>return</b> is the last statement in its (inner) block.
+
+
+
+
+
+<h3>3.3.5 &ndash; <a name="3.3.5">For Statement</a></h3>
+
+<p>
+
+The <b>for</b> statement has two forms:
+one numerical and one generic.
+
+
+
+<h4>The numerical <b>for</b> loop</h4>
+
+<p>
+The numerical <b>for</b> loop repeats a block of code while a
+control variable goes through an arithmetic progression.
+It has the following syntax:
+
+<pre>
+	stat ::= <b>for</b> Name &lsquo;<b>=</b>&rsquo; exp &lsquo;<b>,</b>&rsquo; exp [&lsquo;<b>,</b>&rsquo; exp] <b>do</b> block <b>end</b>
+</pre><p>
+The given identifier (Name) defines the control variable,
+which is a new variable local to the loop body (<em>block</em>).
+
+
+<p>
+The loop starts by evaluating once the three control expressions.
+Their values are called respectively
+the <em>initial value</em>, the <em>limit</em>, and the <em>step</em>.
+If the step is absent, it defaults to&nbsp;1.
+
+
+<p>
+If both the initial value and the step are integers,
+the loop is done with integers;
+note that the limit may not be an integer.
+Otherwise, the three values are converted to
+floats and the loop is done with floats.
+Beware of floating-point accuracy in this case.
+
+
+<p>
+After that initialization,
+the loop body is repeated with the value of the control variable
+going through an arithmetic progression,
+starting at the initial value,
+with a common difference given by the step.
+A negative step makes a decreasing sequence;
+a step equal to zero raises an error.
+The loop continues while the value is less than
+or equal to the limit
+(greater than or equal to for a negative step).
+If the initial value is already greater than the limit
+(or less than, if the step is negative),
+the body is not executed.
+
+
+<p>
+For integer loops,
+the control variable never wraps around;
+instead, the loop ends in case of an overflow.
+
+
+<p>
+You should not change the value of the control variable
+during the loop.
+If you need its value after the loop,
+assign it to another variable before exiting the loop.
+
+
+
+
+
+<h4>The generic <b>for</b> loop</h4>
+
+<p>
+The generic <b>for</b> statement works over functions,
+called <em>iterators</em>.
+On each iteration, the iterator function is called to produce a new value,
+stopping when this new value is <b>nil</b>.
+The generic <b>for</b> loop has the following syntax:
+
+<pre>
+	stat ::= <b>for</b> namelist <b>in</b> explist <b>do</b> block <b>end</b>
+	namelist ::= Name {&lsquo;<b>,</b>&rsquo; Name}
+</pre><p>
+A <b>for</b> statement like
+
+<pre>
+     for <em>var_1</em>, &middot;&middot;&middot;, <em>var_n</em> in <em>explist</em> do <em>body</em> end
+</pre><p>
+works as follows.
+
+
+<p>
+The names <em>var_i</em> declare loop variables local to the loop body.
+The first of these variables is the <em>control variable</em>.
+
+
+<p>
+The loop starts by evaluating <em>explist</em>
+to produce four values:
+an <em>iterator function</em>,
+a <em>state</em>,
+an initial value for the control variable,
+and a <em>closing value</em>.
+
+
+<p>
+Then, at each iteration,
+Lua calls the iterator function with two arguments:
+the state and the control variable.
+The results from this call are then assigned to the loop variables,
+following the rules of multiple assignments (see <a href="#3.3.3">&sect;3.3.3</a>).
+If the control variable becomes <b>nil</b>,
+the loop terminates.
+Otherwise, the body is executed and the loop goes
+to the next iteration.
+
+
+<p>
+The closing value behaves like a
+to-be-closed variable (see <a href="#3.3.8">&sect;3.3.8</a>),
+which can be used to release resources when the loop ends.
+Otherwise, it does not interfere with the loop.
+
+
+<p>
+You should not change the value of the control variable
+during the loop.
+
+
+
+
+
+
+
+<h3>3.3.6 &ndash; <a name="3.3.6">Function Calls as Statements</a></h3><p>
+To allow possible side-effects,
+function calls can be executed as statements:
+
+<pre>
+	stat ::= functioncall
+</pre><p>
+In this case, all returned values are thrown away.
+Function calls are explained in <a href="#3.4.10">&sect;3.4.10</a>.
+
+
+
+
+
+<h3>3.3.7 &ndash; <a name="3.3.7">Local Declarations</a></h3><p>
+Local variables can be declared anywhere inside a block.
+The declaration can include an initialization:
+
+<pre>
+	stat ::= <b>local</b> attnamelist [&lsquo;<b>=</b>&rsquo; explist]
+	attnamelist ::=  Name attrib {&lsquo;<b>,</b>&rsquo; Name attrib}
+</pre><p>
+If present, an initial assignment has the same semantics
+of a multiple assignment (see <a href="#3.3.3">&sect;3.3.3</a>).
+Otherwise, all variables are initialized with <b>nil</b>.
+
+
+<p>
+Each variable name may be postfixed by an attribute
+(a name between angle brackets):
+
+<pre>
+	attrib ::= [&lsquo;<b>&lt;</b>&rsquo; Name &lsquo;<b>&gt;</b>&rsquo;]
+</pre><p>
+There are two possible attributes:
+<code>const</code>, which declares a constant variable,
+that is, a variable that cannot be assigned to
+after its initialization;
+and <code>close</code>, which declares a to-be-closed variable (see <a href="#3.3.8">&sect;3.3.8</a>).
+A list of variables can contain at most one to-be-closed variable.
+
+
+<p>
+A chunk is also a block (see <a href="#3.3.2">&sect;3.3.2</a>),
+and so local variables can be declared in a chunk outside any explicit block.
+
+
+<p>
+The visibility rules for local variables are explained in <a href="#3.5">&sect;3.5</a>.
+
+
+
+
+
+<h3>3.3.8 &ndash; <a name="3.3.8">To-be-closed Variables</a></h3>
+
+<p>
+A to-be-closed variable behaves like a constant local variable,
+except that its value is <em>closed</em> whenever the variable
+goes out of scope, including normal block termination,
+exiting its block by <b>break</b>/<b>goto</b>/<b>return</b>,
+or exiting by an error.
+
+
+<p>
+Here, to <em>close</em> a value means
+to call its <code>__close</code> metamethod.
+When calling the metamethod,
+the value itself is passed as the first argument
+and the error object that caused the exit (if any)
+is passed as a second argument;
+if there was no error, the second argument is <b>nil</b>.
+
+
+<p>
+The value assigned to a to-be-closed variable
+must have a <code>__close</code> metamethod
+or be a false value.
+(<b>nil</b> and <b>false</b> are ignored as to-be-closed values.)
+
+
+<p>
+If several to-be-closed variables go out of scope at the same event,
+they are closed in the reverse order that they were declared.
+
+
+<p>
+If there is any error while running a closing method,
+that error is handled like an error in the regular code
+where the variable was defined.
+However, Lua may call the method one more time.
+
+
+<p>
+After an error,
+the other pending closing methods will still be called.
+Errors in these methods
+interrupt the respective method and generate a warning,
+but are otherwise ignored;
+the error reported is only the original one.
+
+
+<p>
+If a coroutine yields and is never resumed again,
+some variables may never go out of scope,
+and therefore they will never be closed.
+(These variables are the ones created inside the coroutine
+and in scope at the point where the coroutine yielded.)
+Similarly, if a coroutine ends with an error,
+it does not unwind its stack,
+so it does not close any variable.
+In both cases,
+you can either use finalizers
+or call <a href="#pdf-coroutine.close"><code>coroutine.close</code></a> to close the variables.
+However, if the coroutine was created
+through <a href="#pdf-coroutine.wrap"><code>coroutine.wrap</code></a>,
+then its corresponding function will close the coroutine
+in case of errors.
+
+
+
+
+
+
+
+<h2>3.4 &ndash; <a name="3.4">Expressions</a></h2>
+
+
+
+<p>
+The basic expressions in Lua are the following:
+
+<pre>
+	exp ::= prefixexp
+	exp ::= <b>nil</b> | <b>false</b> | <b>true</b>
+	exp ::= Numeral
+	exp ::= LiteralString
+	exp ::= functiondef
+	exp ::= tableconstructor
+	exp ::= &lsquo;<b>...</b>&rsquo;
+	exp ::= exp binop exp
+	exp ::= unop exp
+	prefixexp ::= var | functioncall | &lsquo;<b>(</b>&rsquo; exp &lsquo;<b>)</b>&rsquo;
+</pre>
+
+<p>
+Numerals and literal strings are explained in <a href="#3.1">&sect;3.1</a>;
+variables are explained in <a href="#3.2">&sect;3.2</a>;
+function definitions are explained in <a href="#3.4.11">&sect;3.4.11</a>;
+function calls are explained in <a href="#3.4.10">&sect;3.4.10</a>;
+table constructors are explained in <a href="#3.4.9">&sect;3.4.9</a>.
+Vararg expressions,
+denoted by three dots ('<code>...</code>'), can only be used when
+directly inside a vararg function;
+they are explained in <a href="#3.4.11">&sect;3.4.11</a>.
+
+
+<p>
+Binary operators comprise arithmetic operators (see <a href="#3.4.1">&sect;3.4.1</a>),
+bitwise operators (see <a href="#3.4.2">&sect;3.4.2</a>),
+relational operators (see <a href="#3.4.4">&sect;3.4.4</a>), logical operators (see <a href="#3.4.5">&sect;3.4.5</a>),
+and the concatenation operator (see <a href="#3.4.6">&sect;3.4.6</a>).
+Unary operators comprise the unary minus (see <a href="#3.4.1">&sect;3.4.1</a>),
+the unary bitwise NOT (see <a href="#3.4.2">&sect;3.4.2</a>),
+the unary logical <b>not</b> (see <a href="#3.4.5">&sect;3.4.5</a>),
+and the unary <em>length operator</em> (see <a href="#3.4.7">&sect;3.4.7</a>).
+
+
+<p>
+Both function calls and vararg expressions can result in multiple values.
+If a function call is used as a statement (see <a href="#3.3.6">&sect;3.3.6</a>),
+then its return list is adjusted to zero elements,
+thus discarding all returned values.
+If an expression is used as the last (or the only) element
+of a list of expressions,
+then no adjustment is made
+(unless the expression is enclosed in parentheses).
+In all other contexts,
+Lua adjusts the result list to one element,
+either discarding all values except the first one
+or adding a single <b>nil</b> if there are no values.
+
+
+<p>
+Here are some examples:
+
+<pre>
+     f()                -- adjusted to 0 results
+     g(f(), x)          -- f() is adjusted to 1 result
+     g(x, f())          -- g gets x plus all results from f()
+     a,b,c = f(), x     -- f() is adjusted to 1 result (c gets nil)
+     a,b = ...          -- a gets the first vararg argument, b gets
+                        -- the second (both a and b can get nil if there
+                        -- is no corresponding vararg argument)
+     
+     a,b,c = x, f()     -- f() is adjusted to 2 results
+     a,b,c = f()        -- f() is adjusted to 3 results
+     return f()         -- returns all results from f()
+     return ...         -- returns all received vararg arguments
+     return x,y,f()     -- returns x, y, and all results from f()
+     {f()}              -- creates a list with all results from f()
+     {...}              -- creates a list with all vararg arguments
+     {f(), nil}         -- f() is adjusted to 1 result
+</pre>
+
+<p>
+Any expression enclosed in parentheses always results in only one value.
+Thus,
+<code>(f(x,y,z))</code> is always a single value,
+even if <code>f</code> returns several values.
+(The value of <code>(f(x,y,z))</code> is the first value returned by <code>f</code>
+or <b>nil</b> if <code>f</code> does not return any values.)
+
+
+
+
+
+<h3>3.4.1 &ndash; <a name="3.4.1">Arithmetic Operators</a></h3><p>
+Lua supports the following arithmetic operators:
+
+<ul>
+<li><b><code>+</code>: </b>addition</li>
+<li><b><code>-</code>: </b>subtraction</li>
+<li><b><code>*</code>: </b>multiplication</li>
+<li><b><code>/</code>: </b>float division</li>
+<li><b><code>//</code>: </b>floor division</li>
+<li><b><code>%</code>: </b>modulo</li>
+<li><b><code>^</code>: </b>exponentiation</li>
+<li><b><code>-</code>: </b>unary minus</li>
+</ul>
+
+<p>
+With the exception of exponentiation and float division,
+the arithmetic operators work as follows:
+If both operands are integers,
+the operation is performed over integers and the result is an integer.
+Otherwise, if both operands are numbers,
+then they are converted to floats,
+the operation is performed following the machine's rules
+for floating-point arithmetic
+(usually the IEEE 754 standard),
+and the result is a float.
+(The string library coerces strings to numbers in
+arithmetic operations; see <a href="#3.4.3">&sect;3.4.3</a> for details.)
+
+
+<p>
+Exponentiation and float division (<code>/</code>)
+always convert their operands to floats
+and the result is always a float.
+Exponentiation uses the ISO&nbsp;C function <code>pow</code>,
+so that it works for non-integer exponents too.
+
+
+<p>
+Floor division (<code>//</code>) is a division
+that rounds the quotient towards minus infinity,
+resulting in the floor of the division of its operands.
+
+
+<p>
+Modulo is defined as the remainder of a division
+that rounds the quotient towards minus infinity (floor division).
+
+
+<p>
+In case of overflows in integer arithmetic,
+all operations <em>wrap around</em>.
+
+
+
+<h3>3.4.2 &ndash; <a name="3.4.2">Bitwise Operators</a></h3><p>
+Lua supports the following bitwise operators:
+
+<ul>
+<li><b><code>&amp;</code>: </b>bitwise AND</li>
+<li><b><code>&#124;</code>: </b>bitwise OR</li>
+<li><b><code>~</code>: </b>bitwise exclusive OR</li>
+<li><b><code>&gt;&gt;</code>: </b>right shift</li>
+<li><b><code>&lt;&lt;</code>: </b>left shift</li>
+<li><b><code>~</code>: </b>unary bitwise NOT</li>
+</ul>
+
+<p>
+All bitwise operations convert its operands to integers
+(see <a href="#3.4.3">&sect;3.4.3</a>),
+operate on all bits of those integers,
+and result in an integer.
+
+
+<p>
+Both right and left shifts fill the vacant bits with zeros.
+Negative displacements shift to the other direction;
+displacements with absolute values equal to or higher than
+the number of bits in an integer
+result in zero (as all bits are shifted out).
+
+
+
+
+
+<h3>3.4.3 &ndash; <a name="3.4.3">Coercions and Conversions</a></h3><p>
+Lua provides some automatic conversions between some
+types and representations at run time.
+Bitwise operators always convert float operands to integers.
+Exponentiation and float division
+always convert integer operands to floats.
+All other arithmetic operations applied to mixed numbers
+(integers and floats) convert the integer operand to a float.
+The C API also converts both integers to floats and
+floats to integers, as needed.
+Moreover, string concatenation accepts numbers as arguments,
+besides strings.
+
+
+<p>
+In a conversion from integer to float,
+if the integer value has an exact representation as a float,
+that is the result.
+Otherwise,
+the conversion gets the nearest higher or
+the nearest lower representable value.
+This kind of conversion never fails.
+
+
+<p>
+The conversion from float to integer
+checks whether the float has an exact representation as an integer
+(that is, the float has an integral value and
+it is in the range of integer representation).
+If it does, that representation is the result.
+Otherwise, the conversion fails.
+
+
+<p>
+Several places in Lua coerce strings to numbers when necessary.
+In particular,
+the string library sets metamethods that try to coerce
+strings to numbers in all arithmetic operations.
+If the conversion fails,
+the library calls the metamethod of the other operand
+(if present) or it raises an error.
+Note that bitwise operators do not do this coercion.
+
+
+<p>
+Nonetheless, it is always a good practice not to rely on these
+implicit coercions, as they are not always applied;
+in particular, <code>"1"==1</code> is false and <code>"1"&lt;1</code> raises an error
+(see <a href="#3.4.4">&sect;3.4.4</a>).
+These coercions exist mainly for compatibility and may be removed
+in future versions of the language.
+
+
+<p>
+A string is converted to an integer or a float
+following its syntax and the rules of the Lua lexer.
+The string may have also leading and trailing whitespaces and a sign.
+All conversions from strings to numbers
+accept both a dot and the current locale mark
+as the radix character.
+(The Lua lexer, however, accepts only a dot.)
+If the string is not a valid numeral,
+the conversion fails.
+If necessary, the result of this first step is then converted
+to a specific number subtype following the previous rules
+for conversions between floats and integers.
+
+
+<p>
+The conversion from numbers to strings uses a
+non-specified human-readable format.
+To convert numbers to strings in any specific way,
+use the function <a href="#pdf-string.format"><code>string.format</code></a>.
+
+
+
+
+
+<h3>3.4.4 &ndash; <a name="3.4.4">Relational Operators</a></h3><p>
+Lua supports the following relational operators:
+
+<ul>
+<li><b><code>==</code>: </b>equality</li>
+<li><b><code>~=</code>: </b>inequality</li>
+<li><b><code>&lt;</code>: </b>less than</li>
+<li><b><code>&gt;</code>: </b>greater than</li>
+<li><b><code>&lt;=</code>: </b>less or equal</li>
+<li><b><code>&gt;=</code>: </b>greater or equal</li>
+</ul><p>
+These operators always result in <b>false</b> or <b>true</b>.
+
+
+<p>
+Equality (<code>==</code>) first compares the type of its operands.
+If the types are different, then the result is <b>false</b>.
+Otherwise, the values of the operands are compared.
+Strings are equal if they have the same byte content.
+Numbers are equal if they denote the same mathematical value.
+
+
+<p>
+Tables, userdata, and threads
+are compared by reference:
+two objects are considered equal only if they are the same object.
+Every time you create a new object
+(a table, a userdata, or a thread),
+this new object is different from any previously existing object.
+A function is always equal to itself.
+Functions with any detectable difference
+(different behavior, different definition) are always different.
+Functions created at different times but with no detectable differences
+may be classified as equal or not
+(depending on internal caching details).
+
+
+<p>
+You can change the way that Lua compares tables and userdata
+by using the <code>__eq</code> metamethod (see <a href="#2.4">&sect;2.4</a>).
+
+
+<p>
+Equality comparisons do not convert strings to numbers
+or vice versa.
+Thus, <code>"0"==0</code> evaluates to <b>false</b>,
+and <code>t[0]</code> and <code>t["0"]</code> denote different
+entries in a table.
+
+
+<p>
+The operator <code>~=</code> is exactly the negation of equality (<code>==</code>).
+
+
+<p>
+The order operators work as follows.
+If both arguments are numbers,
+then they are compared according to their mathematical values,
+regardless of their subtypes.
+Otherwise, if both arguments are strings,
+then their values are compared according to the current locale.
+Otherwise, Lua tries to call the <code>__lt</code> or the <code>__le</code>
+metamethod (see <a href="#2.4">&sect;2.4</a>).
+A comparison <code>a &gt; b</code> is translated to <code>b &lt; a</code>
+and <code>a &gt;= b</code> is translated to <code>b &lt;= a</code>.
+
+
+<p>
+Following the IEEE 754 standard,
+the special value NaN is considered neither less than,
+nor equal to, nor greater than any value, including itself.
+
+
+
+
+
+<h3>3.4.5 &ndash; <a name="3.4.5">Logical Operators</a></h3><p>
+The logical operators in Lua are
+<b>and</b>, <b>or</b>, and <b>not</b>.
+Like the control structures (see <a href="#3.3.4">&sect;3.3.4</a>),
+all logical operators consider both <b>false</b> and <b>nil</b> as false
+and anything else as true.
+
+
+<p>
+The negation operator <b>not</b> always returns <b>false</b> or <b>true</b>.
+The conjunction operator <b>and</b> returns its first argument
+if this value is <b>false</b> or <b>nil</b>;
+otherwise, <b>and</b> returns its second argument.
+The disjunction operator <b>or</b> returns its first argument
+if this value is different from <b>nil</b> and <b>false</b>;
+otherwise, <b>or</b> returns its second argument.
+Both <b>and</b> and <b>or</b> use short-circuit evaluation;
+that is,
+the second operand is evaluated only if necessary.
+Here are some examples:
+
+<pre>
+     10 or 20            --&gt; 10
+     10 or error()       --&gt; 10
+     nil or "a"          --&gt; "a"
+     nil and 10          --&gt; nil
+     false and error()   --&gt; false
+     false and nil       --&gt; false
+     false or nil        --&gt; nil
+     10 and 20           --&gt; 20
+</pre>
+
+
+
+
+<h3>3.4.6 &ndash; <a name="3.4.6">Concatenation</a></h3><p>
+The string concatenation operator in Lua is
+denoted by two dots ('<code>..</code>').
+If both operands are strings or numbers,
+then the numbers are converted to strings
+in a non-specified format (see <a href="#3.4.3">&sect;3.4.3</a>).
+Otherwise, the <code>__concat</code> metamethod is called (see <a href="#2.4">&sect;2.4</a>).
+
+
+
+
+
+<h3>3.4.7 &ndash; <a name="3.4.7">The Length Operator</a></h3>
+
+<p>
+The length operator is denoted by the unary prefix operator <code>#</code>.
+
+
+<p>
+The length of a string is its number of bytes.
+(That is the usual meaning of string length when each
+character is one byte.)
+
+
+<p>
+The length operator applied on a table
+returns a border in that table.
+A <em>border</em> in a table <code>t</code> is any natural number
+that satisfies the following condition:
+
+<pre>
+     (border == 0 or t[border] ~= nil) and t[border + 1] == nil
+</pre><p>
+In words,
+a border is any (natural) index present in the table
+that is followed by an absent index
+(or zero, when index 1 is absent).
+
+
+<p>
+A table with exactly one border is called a <em>sequence</em>.
+For instance, the table <code>{10, 20, 30, 40, 50}</code> is a sequence,
+as it has only one border (5).
+The table <code>{10, 20, 30, nil, 50}</code> has two borders (3 and 5),
+and therefore it is not a sequence.
+(The <b>nil</b> at index 4 is called a <em>hole</em>.)
+The table <code>{nil, 20, 30, nil, nil, 60, nil}</code>
+has three borders (0, 3, and 6) and three holes
+(at indices 1, 4, and 5),
+so it is not a sequence, too.
+The table <code>{}</code> is a sequence with border 0.
+Note that non-natural keys do not interfere
+with whether a table is a sequence.
+
+
+<p>
+When <code>t</code> is a sequence,
+<code>#t</code> returns its only border,
+which corresponds to the intuitive notion of the length of the sequence.
+When <code>t</code> is not a sequence,
+<code>#t</code> can return any of its borders.
+(The exact one depends on details of
+the internal representation of the table,
+which in turn can depend on how the table was populated and
+the memory addresses of its non-numeric keys.)
+
+
+<p>
+The computation of the length of a table
+has a guaranteed worst time of <em>O(log n)</em>,
+where <em>n</em> is the largest natural key in the table.
+
+
+<p>
+A program can modify the behavior of the length operator for
+any value but strings through the <code>__len</code> metamethod (see <a href="#2.4">&sect;2.4</a>).
+
+
+
+
+
+<h3>3.4.8 &ndash; <a name="3.4.8">Precedence</a></h3><p>
+Operator precedence in Lua follows the table below,
+from lower to higher priority:
+
+<pre>
+     or
+     and
+     &lt;     &gt;     &lt;=    &gt;=    ~=    ==
+     |
+     ~
+     &amp;
+     &lt;&lt;    &gt;&gt;
+     ..
+     +     -
+     *     /     //    %
+     unary operators (not   #     -     ~)
+     ^
+</pre><p>
+As usual,
+you can use parentheses to change the precedences of an expression.
+The concatenation ('<code>..</code>') and exponentiation ('<code>^</code>')
+operators are right associative.
+All other binary operators are left associative.
+
+
+
+
+
+<h3>3.4.9 &ndash; <a name="3.4.9">Table Constructors</a></h3><p>
+Table constructors are expressions that create tables.
+Every time a constructor is evaluated, a new table is created.
+A constructor can be used to create an empty table
+or to create a table and initialize some of its fields.
+The general syntax for constructors is
+
+<pre>
+	tableconstructor ::= &lsquo;<b>{</b>&rsquo; [fieldlist] &lsquo;<b>}</b>&rsquo;
+	fieldlist ::= field {fieldsep field} [fieldsep]
+	field ::= &lsquo;<b>[</b>&rsquo; exp &lsquo;<b>]</b>&rsquo; &lsquo;<b>=</b>&rsquo; exp | Name &lsquo;<b>=</b>&rsquo; exp | exp
+	fieldsep ::= &lsquo;<b>,</b>&rsquo; | &lsquo;<b>;</b>&rsquo;
+</pre>
+
+<p>
+Each field of the form <code>[exp1] = exp2</code> adds to the new table an entry
+with key <code>exp1</code> and value <code>exp2</code>.
+A field of the form <code>name = exp</code> is equivalent to
+<code>["name"] = exp</code>.
+Fields of the form <code>exp</code> are equivalent to
+<code>[i] = exp</code>, where <code>i</code> are consecutive integers
+starting with 1;
+fields in the other formats do not affect this counting.
+For example,
+
+<pre>
+     a = { [f(1)] = g; "x", "y"; x = 1, f(x), [30] = 23; 45 }
+</pre><p>
+is equivalent to
+
+<pre>
+     do
+       local t = {}
+       t[f(1)] = g
+       t[1] = "x"         -- 1st exp
+       t[2] = "y"         -- 2nd exp
+       t.x = 1            -- t["x"] = 1
+       t[3] = f(x)        -- 3rd exp
+       t[30] = 23
+       t[4] = 45          -- 4th exp
+       a = t
+     end
+</pre>
+
+<p>
+The order of the assignments in a constructor is undefined.
+(This order would be relevant only when there are repeated keys.)
+
+
+<p>
+If the last field in the list has the form <code>exp</code>
+and the expression is a function call or a vararg expression,
+then all values returned by this expression enter the list consecutively
+(see <a href="#3.4.10">&sect;3.4.10</a>).
+
+
+<p>
+The field list can have an optional trailing separator,
+as a convenience for machine-generated code.
+
+
+
+
+
+<h3>3.4.10 &ndash; <a name="3.4.10">Function Calls</a></h3><p>
+A function call in Lua has the following syntax:
+
+<pre>
+	functioncall ::= prefixexp args
+</pre><p>
+In a function call,
+first prefixexp and args are evaluated.
+If the value of prefixexp has type <em>function</em>,
+then this function is called
+with the given arguments.
+Otherwise, if present,
+the prefixexp <code>__call</code> metamethod is called:
+its first argument is the value of prefixexp,
+followed by the original call arguments
+(see <a href="#2.4">&sect;2.4</a>).
+
+
+<p>
+The form
+
+<pre>
+	functioncall ::= prefixexp &lsquo;<b>:</b>&rsquo; Name args
+</pre><p>
+can be used to emulate methods.
+A call <code>v:name(<em>args</em>)</code>
+is syntactic sugar for <code>v.name(v,<em>args</em>)</code>,
+except that <code>v</code> is evaluated only once.
+
+
+<p>
+Arguments have the following syntax:
+
+<pre>
+	args ::= &lsquo;<b>(</b>&rsquo; [explist] &lsquo;<b>)</b>&rsquo;
+	args ::= tableconstructor
+	args ::= LiteralString
+</pre><p>
+All argument expressions are evaluated before the call.
+A call of the form <code>f{<em>fields</em>}</code> is
+syntactic sugar for <code>f({<em>fields</em>})</code>;
+that is, the argument list is a single new table.
+A call of the form <code>f'<em>string</em>'</code>
+(or <code>f"<em>string</em>"</code> or <code>f[[<em>string</em>]]</code>)
+is syntactic sugar for <code>f('<em>string</em>')</code>;
+that is, the argument list is a single literal string.
+
+
+<p>
+A call of the form <code>return <em>functioncall</em></code> not in the
+scope of a to-be-closed variable is called a <em>tail call</em>.
+Lua implements <em>proper tail calls</em>
+(or <em>proper tail recursion</em>):
+in a tail call,
+the called function reuses the stack entry of the calling function.
+Therefore, there is no limit on the number of nested tail calls that
+a program can execute.
+However, a tail call erases any debug information about the
+calling function.
+Note that a tail call only happens with a particular syntax,
+where the <b>return</b> has one single function call as argument,
+and it is outside the scope of any to-be-closed variable.
+This syntax makes the calling function return exactly
+the returns of the called function,
+without any intervening action.
+So, none of the following examples are tail calls:
+
+<pre>
+     return (f(x))        -- results adjusted to 1
+     return 2 * f(x)      -- result multiplied by 2
+     return x, f(x)       -- additional results
+     f(x); return         -- results discarded
+     return x or f(x)     -- results adjusted to 1
+</pre>
+
+
+
+
+<h3>3.4.11 &ndash; <a name="3.4.11">Function Definitions</a></h3>
+
+<p>
+The syntax for function definition is
+
+<pre>
+	functiondef ::= <b>function</b> funcbody
+	funcbody ::= &lsquo;<b>(</b>&rsquo; [parlist] &lsquo;<b>)</b>&rsquo; block <b>end</b>
+</pre>
+
+<p>
+The following syntactic sugar simplifies function definitions:
+
+<pre>
+	stat ::= <b>function</b> funcname funcbody
+	stat ::= <b>local</b> <b>function</b> Name funcbody
+	funcname ::= Name {&lsquo;<b>.</b>&rsquo; Name} [&lsquo;<b>:</b>&rsquo; Name]
+</pre><p>
+The statement
+
+<pre>
+     function f () <em>body</em> end
+</pre><p>
+translates to
+
+<pre>
+     f = function () <em>body</em> end
+</pre><p>
+The statement
+
+<pre>
+     function t.a.b.c.f () <em>body</em> end
+</pre><p>
+translates to
+
+<pre>
+     t.a.b.c.f = function () <em>body</em> end
+</pre><p>
+The statement
+
+<pre>
+     local function f () <em>body</em> end
+</pre><p>
+translates to
+
+<pre>
+     local f; f = function () <em>body</em> end
+</pre><p>
+not to
+
+<pre>
+     local f = function () <em>body</em> end
+</pre><p>
+(This only makes a difference when the body of the function
+contains references to <code>f</code>.)
+
+
+<p>
+A function definition is an executable expression,
+whose value has type <em>function</em>.
+When Lua precompiles a chunk,
+all its function bodies are precompiled too,
+but they are not created yet.
+Then, whenever Lua executes the function definition,
+the function is <em>instantiated</em> (or <em>closed</em>).
+This function instance, or <em>closure</em>,
+is the final value of the expression.
+
+
+<p>
+Parameters act as local variables that are
+initialized with the argument values:
+
+<pre>
+	parlist ::= namelist [&lsquo;<b>,</b>&rsquo; &lsquo;<b>...</b>&rsquo;] | &lsquo;<b>...</b>&rsquo;
+</pre><p>
+When a Lua function is called,
+it adjusts its list of arguments to
+the length of its list of parameters,
+unless the function is a <em>vararg function</em>,
+which is indicated by three dots ('<code>...</code>')
+at the end of its parameter list.
+A vararg function does not adjust its argument list;
+instead, it collects all extra arguments and supplies them
+to the function through a <em>vararg expression</em>,
+which is also written as three dots.
+The value of this expression is a list of all actual extra arguments,
+similar to a function with multiple results.
+If a vararg expression is used inside another expression
+or in the middle of a list of expressions,
+then its return list is adjusted to one element.
+If the expression is used as the last element of a list of expressions,
+then no adjustment is made
+(unless that last expression is enclosed in parentheses).
+
+
+<p>
+As an example, consider the following definitions:
+
+<pre>
+     function f(a, b) end
+     function g(a, b, ...) end
+     function r() return 1,2,3 end
+</pre><p>
+Then, we have the following mapping from arguments to parameters and
+to the vararg expression:
+
+<pre>
+     CALL             PARAMETERS
+     
+     f(3)             a=3, b=nil
+     f(3, 4)          a=3, b=4
+     f(3, 4, 5)       a=3, b=4
+     f(r(), 10)       a=1, b=10
+     f(r())           a=1, b=2
+     
+     g(3)             a=3, b=nil, ... --&gt;  (nothing)
+     g(3, 4)          a=3, b=4,   ... --&gt;  (nothing)
+     g(3, 4, 5, 8)    a=3, b=4,   ... --&gt;  5  8
+     g(5, r())        a=5, b=1,   ... --&gt;  2  3
+</pre>
+
+<p>
+Results are returned using the <b>return</b> statement (see <a href="#3.3.4">&sect;3.3.4</a>).
+If control reaches the end of a function
+without encountering a <b>return</b> statement,
+then the function returns with no results.
+
+
+<p>
+
+There is a system-dependent limit on the number of values
+that a function may return.
+This limit is guaranteed to be greater than 1000.
+
+
+<p>
+The <em>colon</em> syntax
+is used to emulate <em>methods</em>,
+adding an implicit extra parameter <code>self</code> to the function.
+Thus, the statement
+
+<pre>
+     function t.a.b.c:f (<em>params</em>) <em>body</em> end
+</pre><p>
+is syntactic sugar for
+
+<pre>
+     t.a.b.c.f = function (self, <em>params</em>) <em>body</em> end
+</pre>
+
+
+
+
+
+
+<h2>3.5 &ndash; <a name="3.5">Visibility Rules</a></h2>
+
+<p>
+
+Lua is a lexically scoped language.
+The scope of a local variable begins at the first statement after
+its declaration and lasts until the last non-void statement
+of the innermost block that includes the declaration.
+Consider the following example:
+
+<pre>
+     x = 10                -- global variable
+     do                    -- new block
+       local x = x         -- new 'x', with value 10
+       print(x)            --&gt; 10
+       x = x+1
+       do                  -- another block
+         local x = x+1     -- another 'x'
+         print(x)          --&gt; 12
+       end
+       print(x)            --&gt; 11
+     end
+     print(x)              --&gt; 10  (the global one)
+</pre>
+
+<p>
+Notice that, in a declaration like <code>local x = x</code>,
+the new <code>x</code> being declared is not in scope yet,
+and so the second <code>x</code> refers to the outside variable.
+
+
+<p>
+Because of the lexical scoping rules,
+local variables can be freely accessed by functions
+defined inside their scope.
+A local variable used by an inner function is called an <em>upvalue</em>
+(or <em>external local variable</em>, or simply <em>external variable</em>)
+inside the inner function.
+
+
+<p>
+Notice that each execution of a <b>local</b> statement
+defines new local variables.
+Consider the following example:
+
+<pre>
+     a = {}
+     local x = 20
+     for i = 1, 10 do
+       local y = 0
+       a[i] = function () y = y + 1; return x + y end
+     end
+</pre><p>
+The loop creates ten closures
+(that is, ten instances of the anonymous function).
+Each of these closures uses a different <code>y</code> variable,
+while all of them share the same <code>x</code>.
+
+
+
+
+
+<h1>4 &ndash; <a name="4">The Application Program Interface</a></h1>
+
+
+
+<p>
+
+This section describes the C&nbsp;API for Lua, that is,
+the set of C&nbsp;functions available to the host program to communicate
+with Lua.
+All API functions and related types and constants
+are declared in the header file <a name="pdf-lua.h"><code>lua.h</code></a>.
+
+
+<p>
+Even when we use the term "function",
+any facility in the API may be provided as a macro instead.
+Except where stated otherwise,
+all such macros use each of their arguments exactly once
+(except for the first argument, which is always a Lua state),
+and so do not generate any hidden side-effects.
+
+
+<p>
+As in most C&nbsp;libraries,
+the Lua API functions do not check their arguments
+for validity or consistency.
+However, you can change this behavior by compiling Lua
+with the macro <a name="pdf-LUA_USE_APICHECK"><code>LUA_USE_APICHECK</code></a> defined.
+
+
+<p>
+The Lua library is fully reentrant:
+it has no global variables.
+It keeps all information it needs in a dynamic structure,
+called the <em>Lua state</em>.
+
+
+<p>
+Each Lua state has one or more threads,
+which correspond to independent, cooperative lines of execution.
+The type <a href="#lua_State"><code>lua_State</code></a> (despite its name) refers to a thread.
+(Indirectly, through the thread, it also refers to the
+Lua state associated to the thread.)
+
+
+<p>
+A pointer to a thread must be passed as the first argument to
+every function in the library, except to <a href="#lua_newstate"><code>lua_newstate</code></a>,
+which creates a Lua state from scratch and returns a pointer
+to the <em>main thread</em> in the new state.
+
+
+
+
+
+<h2>4.1 &ndash; <a name="4.1">The Stack</a></h2>
+
+
+
+<p>
+Lua uses a <em>virtual stack</em> to pass values to and from C.
+Each element in this stack represents a Lua value
+(<b>nil</b>, number, string, etc.).
+Functions in the API can access this stack through the
+Lua state parameter that they receive.
+
+
+<p>
+Whenever Lua calls C, the called function gets a new stack,
+which is independent of previous stacks and of stacks of
+C&nbsp;functions that are still active.
+This stack initially contains any arguments to the C&nbsp;function
+and it is where the C&nbsp;function can store temporary
+Lua values and must push its results
+to be returned to the caller (see <a href="#lua_CFunction"><code>lua_CFunction</code></a>).
+
+
+<p>
+For convenience,
+most query operations in the API do not follow a strict stack discipline.
+Instead, they can refer to any element in the stack
+by using an <em>index</em>:
+A positive index represents an absolute stack position,
+starting at&nbsp;1 as the bottom of the stack;
+a negative index represents an offset relative to the top of the stack.
+More specifically, if the stack has <em>n</em> elements,
+then index&nbsp;1 represents the first element
+(that is, the element that was pushed onto the stack first)
+and
+index&nbsp;<em>n</em> represents the last element;
+index&nbsp;-1 also represents the last element
+(that is, the element at the&nbsp;top)
+and index <em>-n</em> represents the first element.
+
+
+
+
+
+<h3>4.1.1 &ndash; <a name="4.1.1">Stack Size</a></h3>
+
+<p>
+When you interact with the Lua API,
+you are responsible for ensuring consistency.
+In particular,
+<em>you are responsible for controlling stack overflow</em>.
+You can use the function <a href="#lua_checkstack"><code>lua_checkstack</code></a>
+to ensure that the stack has enough space for pushing new elements.
+
+
+<p>
+Whenever Lua calls C,
+it ensures that the stack has space for
+at least <a name="pdf-LUA_MINSTACK"><code>LUA_MINSTACK</code></a> extra slots.
+<code>LUA_MINSTACK</code> is defined as 20,
+so that usually you do not have to worry about stack space
+unless your code has loops pushing elements onto the stack.
+
+
+<p>
+When you call a Lua function
+without a fixed number of results (see <a href="#lua_call"><code>lua_call</code></a>),
+Lua ensures that the stack has enough space for all results,
+but it does not ensure any extra space.
+So, before pushing anything in the stack after such a call
+you should use <a href="#lua_checkstack"><code>lua_checkstack</code></a>.
+
+
+
+
+
+<h3>4.1.2 &ndash; <a name="4.1.2">Valid and Acceptable Indices</a></h3>
+
+<p>
+Any function in the API that receives stack indices
+works only with <em>valid indices</em> or <em>acceptable indices</em>.
+
+
+<p>
+A <em>valid index</em> is an index that refers to a
+position that stores a modifiable Lua value.
+It comprises stack indices between&nbsp;1 and the stack top
+(<code>1 &le; abs(index) &le; top</code>)
+
+plus <em>pseudo-indices</em>,
+which represent some positions that are accessible to C&nbsp;code
+but that are not in the stack.
+Pseudo-indices are used to access the registry (see <a href="#4.3">&sect;4.3</a>)
+and the upvalues of a C&nbsp;function (see <a href="#4.2">&sect;4.2</a>).
+
+
+<p>
+Functions that do not need a specific mutable position,
+but only a value (e.g., query functions),
+can be called with acceptable indices.
+An <em>acceptable index</em> can be any valid index,
+but it also can be any positive index after the stack top
+within the space allocated for the stack,
+that is, indices up to the stack size.
+(Note that 0 is never an acceptable index.)
+Indices to upvalues (see <a href="#4.2">&sect;4.2</a>) greater than the real number
+of upvalues in the current C&nbsp;function are also acceptable (but invalid).
+Except when noted otherwise,
+functions in the API work with acceptable indices.
+
+
+<p>
+Acceptable indices serve to avoid extra tests
+against the stack top when querying the stack.
+For instance, a C&nbsp;function can query its third argument
+without the need to check whether there is a third argument,
+that is, without the need to check whether 3 is a valid index.
+
+
+<p>
+For functions that can be called with acceptable indices,
+any non-valid index is treated as if it
+contains a value of a virtual type <a name="pdf-LUA_TNONE"><code>LUA_TNONE</code></a>,
+which behaves like a nil value.
+
+
+
+
+
+
+
+<h2>4.2 &ndash; <a name="4.2">C Closures</a></h2>
+
+<p>
+When a C&nbsp;function is created,
+it is possible to associate some values with it,
+thus creating a <em>C&nbsp;closure</em>
+(see <a href="#lua_pushcclosure"><code>lua_pushcclosure</code></a>);
+these values are called <em>upvalues</em> and are
+accessible to the function whenever it is called.
+
+
+<p>
+Whenever a C&nbsp;function is called,
+its upvalues are located at specific pseudo-indices.
+These pseudo-indices are produced by the macro
+<a href="#lua_upvalueindex"><code>lua_upvalueindex</code></a>.
+The first upvalue associated with a function is at index
+<code>lua_upvalueindex(1)</code>, and so on.
+Any access to <code>lua_upvalueindex(<em>n</em>)</code>,
+where <em>n</em> is greater than the number of upvalues of the
+current function
+(but not greater than 256,
+which is one plus the maximum number of upvalues in a closure),
+produces an acceptable but invalid index.
+
+
+<p>
+A C&nbsp;closure can also change the values
+of its corresponding upvalues.
+
+
+
+
+
+<h2>4.3 &ndash; <a name="4.3">Registry</a></h2>
+
+<p>
+Lua provides a <em>registry</em>,
+a predefined table that can be used by any C&nbsp;code to
+store whatever Lua values it needs to store.
+The registry table is always accessible at pseudo-index
+<a name="pdf-LUA_REGISTRYINDEX"><code>LUA_REGISTRYINDEX</code></a>.
+Any C&nbsp;library can store data into this table,
+but it must take care to choose keys
+that are different from those used
+by other libraries, to avoid collisions.
+Typically, you should use as key a string containing your library name,
+or a light userdata with the address of a C&nbsp;object in your code,
+or any Lua object created by your code.
+As with variable names,
+string keys starting with an underscore followed by
+uppercase letters are reserved for Lua.
+
+
+<p>
+The integer keys in the registry are used
+by the reference mechanism (see <a href="#luaL_ref"><code>luaL_ref</code></a>)
+and by some predefined values.
+Therefore, integer keys in the registry
+must not be used for other purposes.
+
+
+<p>
+When you create a new Lua state,
+its registry comes with some predefined values.
+These predefined values are indexed with integer keys
+defined as constants in <code>lua.h</code>.
+The following constants are defined:
+
+<ul>
+<li><b><a name="pdf-LUA_RIDX_MAINTHREAD"><code>LUA_RIDX_MAINTHREAD</code></a>: </b> At this index the registry has
+the main thread of the state.
+(The main thread is the one created together with the state.)
+</li>
+
+<li><b><a name="pdf-LUA_RIDX_GLOBALS"><code>LUA_RIDX_GLOBALS</code></a>: </b> At this index the registry has
+the global environment.
+</li>
+</ul>
+
+
+
+
+<h2>4.4 &ndash; <a name="4.4">Error Handling in C</a></h2>
+
+
+
+<p>
+Internally, Lua uses the C <code>longjmp</code> facility to handle errors.
+(Lua will use exceptions if you compile it as C++;
+search for <code>LUAI_THROW</code> in the source code for details.)
+When Lua faces any error,
+such as a memory allocation error or a type error,
+it <em>raises</em> an error;
+that is, it does a long jump.
+A <em>protected environment</em> uses <code>setjmp</code>
+to set a recovery point;
+any error jumps to the most recent active recovery point.
+
+
+<p>
+Inside a C&nbsp;function you can raise an error explicitly
+by calling <a href="#lua_error"><code>lua_error</code></a>.
+
+
+<p>
+Most functions in the API can raise an error,
+for instance due to a memory allocation error.
+The documentation for each function indicates whether
+it can raise errors.
+
+
+<p>
+If an error happens outside any protected environment,
+Lua calls a <em>panic function</em> (see <a href="#lua_atpanic"><code>lua_atpanic</code></a>)
+and then calls <code>abort</code>,
+thus exiting the host application.
+Your panic function can avoid this exit by
+never returning
+(e.g., doing a long jump to your own recovery point outside Lua).
+
+
+<p>
+The panic function,
+as its name implies,
+is a mechanism of last resort.
+Programs should avoid it.
+As a general rule,
+when a C&nbsp;function is called by Lua with a Lua state,
+it can do whatever it wants on that Lua state,
+as it should be already protected.
+However,
+when C code operates on other Lua states
+(e.g., a Lua-state argument to the function,
+a Lua state stored in the registry, or
+the result of <a href="#lua_newthread"><code>lua_newthread</code></a>),
+it should use them only in API calls that cannot raise errors.
+
+
+<p>
+The panic function runs as if it were a message handler (see <a href="#2.3">&sect;2.3</a>);
+in particular, the error object is on the top of the stack.
+However, there is no guarantee about stack space.
+To push anything on the stack,
+the panic function must first check the available space (see <a href="#4.1.1">&sect;4.1.1</a>).
+
+
+
+
+
+<h3>4.4.1 &ndash; <a name="4.4.1">Status Codes</a></h3>
+
+<p>
+Several functions that report errors in the API use the following
+status codes to indicate different kinds of errors or other conditions:
+
+<ul>
+
+<li><b><a name="pdf-LUA_OK"><code>LUA_OK</code></a> (0): </b> no errors.</li>
+
+<li><b><a name="pdf-LUA_ERRRUN"><code>LUA_ERRRUN</code></a>: </b> a runtime error.</li>
+
+<li><b><a name="pdf-LUA_ERRMEM"><code>LUA_ERRMEM</code></a>: </b>
+memory allocation error.
+For such errors, Lua does not call the message handler.
+</li>
+
+<li><b><a name="pdf-LUA_ERRERR"><code>LUA_ERRERR</code></a>: </b> error while running the message handler.</li>
+
+<li><b><a name="pdf-LUA_ERRSYNTAX"><code>LUA_ERRSYNTAX</code></a>: </b> syntax error during precompilation.</li>
+
+<li><b><a name="pdf-LUA_YIELD"><code>LUA_YIELD</code></a>: </b> the thread (coroutine) yields.</li>
+
+<li><b><a name="pdf-LUA_ERRFILE"><code>LUA_ERRFILE</code></a>: </b> a file-related error;
+e.g., it cannot open or read the file.</li>
+
+</ul><p>
+These constants are defined in the header file <code>lua.h</code>.
+
+
+
+
+
+
+
+<h2>4.5 &ndash; <a name="4.5">Handling Yields in C</a></h2>
+
+<p>
+Internally, Lua uses the C <code>longjmp</code> facility to yield a coroutine.
+Therefore, if a C&nbsp;function <code>foo</code> calls an API function
+and this API function yields
+(directly or indirectly by calling another function that yields),
+Lua cannot return to <code>foo</code> any more,
+because the <code>longjmp</code> removes its frame from the C stack.
+
+
+<p>
+To avoid this kind of problem,
+Lua raises an error whenever it tries to yield across an API call,
+except for three functions:
+<a href="#lua_yieldk"><code>lua_yieldk</code></a>, <a href="#lua_callk"><code>lua_callk</code></a>, and <a href="#lua_pcallk"><code>lua_pcallk</code></a>.
+All those functions receive a <em>continuation function</em>
+(as a parameter named <code>k</code>) to continue execution after a yield.
+
+
+<p>
+We need to set some terminology to explain continuations.
+We have a C&nbsp;function called from Lua which we will call
+the <em>original function</em>.
+This original function then calls one of those three functions in the C API,
+which we will call the <em>callee function</em>,
+that then yields the current thread.
+This can happen when the callee function is <a href="#lua_yieldk"><code>lua_yieldk</code></a>,
+or when the callee function is either <a href="#lua_callk"><code>lua_callk</code></a> or <a href="#lua_pcallk"><code>lua_pcallk</code></a>
+and the function called by them yields.
+
+
+<p>
+Suppose the running thread yields while executing the callee function.
+After the thread resumes,
+it eventually will finish running the callee function.
+However,
+the callee function cannot return to the original function,
+because its frame in the C stack was destroyed by the yield.
+Instead, Lua calls a <em>continuation function</em>,
+which was given as an argument to the callee function.
+As the name implies,
+the continuation function should continue the task
+of the original function.
+
+
+<p>
+As an illustration, consider the following function:
+
+<pre>
+     int original_function (lua_State *L) {
+       ...     /* code 1 */
+       status = lua_pcall(L, n, m, h);  /* calls Lua */
+       ...     /* code 2 */
+     }
+</pre><p>
+Now we want to allow
+the Lua code being run by <a href="#lua_pcall"><code>lua_pcall</code></a> to yield.
+First, we can rewrite our function like here:
+
+<pre>
+     int k (lua_State *L, int status, lua_KContext ctx) {
+       ...  /* code 2 */
+     }
+     
+     int original_function (lua_State *L) {
+       ...     /* code 1 */
+       return k(L, lua_pcall(L, n, m, h), ctx);
+     }
+</pre><p>
+In the above code,
+the new function <code>k</code> is a
+<em>continuation function</em> (with type <a href="#lua_KFunction"><code>lua_KFunction</code></a>),
+which should do all the work that the original function
+was doing after calling <a href="#lua_pcall"><code>lua_pcall</code></a>.
+Now, we must inform Lua that it must call <code>k</code> if the Lua code
+being executed by <a href="#lua_pcall"><code>lua_pcall</code></a> gets interrupted in some way
+(errors or yielding),
+so we rewrite the code as here,
+replacing <a href="#lua_pcall"><code>lua_pcall</code></a> by <a href="#lua_pcallk"><code>lua_pcallk</code></a>:
+
+<pre>
+     int original_function (lua_State *L) {
+       ...     /* code 1 */
+       return k(L, lua_pcallk(L, n, m, h, ctx2, k), ctx1);
+     }
+</pre><p>
+Note the external, explicit call to the continuation:
+Lua will call the continuation only if needed, that is,
+in case of errors or resuming after a yield.
+If the called function returns normally without ever yielding,
+<a href="#lua_pcallk"><code>lua_pcallk</code></a> (and <a href="#lua_callk"><code>lua_callk</code></a>) will also return normally.
+(Of course, instead of calling the continuation in that case,
+you can do the equivalent work directly inside the original function.)
+
+
+<p>
+Besides the Lua state,
+the continuation function has two other parameters:
+the final status of the call and the context value (<code>ctx</code>) that
+was passed originally to <a href="#lua_pcallk"><code>lua_pcallk</code></a>.
+Lua does not use this context value;
+it only passes this value from the original function to the
+continuation function.
+For <a href="#lua_pcallk"><code>lua_pcallk</code></a>,
+the status is the same value that would be returned by <a href="#lua_pcallk"><code>lua_pcallk</code></a>,
+except that it is <a href="#pdf-LUA_YIELD"><code>LUA_YIELD</code></a> when being executed after a yield
+(instead of <a href="#pdf-LUA_OK"><code>LUA_OK</code></a>).
+For <a href="#lua_yieldk"><code>lua_yieldk</code></a> and <a href="#lua_callk"><code>lua_callk</code></a>,
+the status is always <a href="#pdf-LUA_YIELD"><code>LUA_YIELD</code></a> when Lua calls the continuation.
+(For these two functions,
+Lua will not call the continuation in case of errors,
+because they do not handle errors.)
+Similarly, when using <a href="#lua_callk"><code>lua_callk</code></a>,
+you should call the continuation function
+with <a href="#pdf-LUA_OK"><code>LUA_OK</code></a> as the status.
+(For <a href="#lua_yieldk"><code>lua_yieldk</code></a>, there is not much point in calling
+directly the continuation function,
+because <a href="#lua_yieldk"><code>lua_yieldk</code></a> usually does not return.)
+
+
+<p>
+Lua treats the continuation function as if it were the original function.
+The continuation function receives the same Lua stack
+from the original function,
+in the same state it would be if the callee function had returned.
+(For instance,
+after a <a href="#lua_callk"><code>lua_callk</code></a> the function and its arguments are
+removed from the stack and replaced by the results from the call.)
+It also has the same upvalues.
+Whatever it returns is handled by Lua as if it were the return
+of the original function.
+
+
+
+
+
+<h2>4.6 &ndash; <a name="4.6">Functions and Types</a></h2>
+
+<p>
+Here we list all functions and types from the C&nbsp;API in
+alphabetical order.
+Each function has an indicator like this:
+<span class="apii">[-o, +p, <em>x</em>]</span>
+
+
+<p>
+The first field, <code>o</code>,
+is how many elements the function pops from the stack.
+The second field, <code>p</code>,
+is how many elements the function pushes onto the stack.
+(Any function always pushes its results after popping its arguments.)
+A field in the form <code>x|y</code> means the function can push (or pop)
+<code>x</code> or <code>y</code> elements,
+depending on the situation;
+an interrogation mark '<code>?</code>' means that
+we cannot know how many elements the function pops/pushes
+by looking only at its arguments.
+(For instance, they may depend on what is on the stack.)
+The third field, <code>x</code>,
+tells whether the function may raise errors:
+'<code>-</code>' means the function never raises any error;
+'<code>m</code>' means the function may raise only out-of-memory errors;
+'<code>v</code>' means the function may raise the errors explained in the text;
+'<code>e</code>' means the function can run arbitrary Lua code,
+either directly or through metamethods,
+and therefore may raise any errors.
+
+
+
+<hr><h3><a name="lua_absindex"><code>lua_absindex</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>int lua_absindex (lua_State *L, int idx);</pre>
+
+<p>
+Converts the acceptable index <code>idx</code>
+into an equivalent absolute index
+(that is, one that does not depend on the stack top).
+
+
+
+
+
+<hr><h3><a name="lua_Alloc"><code>lua_Alloc</code></a></h3>
+<pre>typedef void * (*lua_Alloc) (void *ud,
+                             void *ptr,
+                             size_t osize,
+                             size_t nsize);</pre>
+
+<p>
+The type of the memory-allocation function used by Lua states.
+The allocator function must provide a
+functionality similar to <code>realloc</code>,
+but not exactly the same.
+Its arguments are
+<code>ud</code>, an opaque pointer passed to <a href="#lua_newstate"><code>lua_newstate</code></a>;
+<code>ptr</code>, a pointer to the block being allocated/reallocated/freed;
+<code>osize</code>, the original size of the block or some code about what
+is being allocated;
+and <code>nsize</code>, the new size of the block.
+
+
+<p>
+When <code>ptr</code> is not <code>NULL</code>,
+<code>osize</code> is the size of the block pointed by <code>ptr</code>,
+that is, the size given when it was allocated or reallocated.
+
+
+<p>
+When <code>ptr</code> is <code>NULL</code>,
+<code>osize</code> encodes the kind of object that Lua is allocating.
+<code>osize</code> is any of
+<a href="#pdf-LUA_TSTRING"><code>LUA_TSTRING</code></a>, <a href="#pdf-LUA_TTABLE"><code>LUA_TTABLE</code></a>, <a href="#pdf-LUA_TFUNCTION"><code>LUA_TFUNCTION</code></a>,
+<a href="#pdf-LUA_TUSERDATA"><code>LUA_TUSERDATA</code></a>, or <a href="#pdf-LUA_TTHREAD"><code>LUA_TTHREAD</code></a> when (and only when)
+Lua is creating a new object of that type.
+When <code>osize</code> is some other value,
+Lua is allocating memory for something else.
+
+
+<p>
+Lua assumes the following behavior from the allocator function:
+
+
+<p>
+When <code>nsize</code> is zero,
+the allocator must behave like <code>free</code>
+and then return <code>NULL</code>.
+
+
+<p>
+When <code>nsize</code> is not zero,
+the allocator must behave like <code>realloc</code>.
+In particular, the allocator returns <code>NULL</code>
+if and only if it cannot fulfill the request.
+
+
+<p>
+Here is a simple implementation for the allocator function.
+It is used in the auxiliary library by <a href="#luaL_newstate"><code>luaL_newstate</code></a>.
+
+<pre>
+     static void *l_alloc (void *ud, void *ptr, size_t osize,
+                                                size_t nsize) {
+       (void)ud;  (void)osize;  /* not used */
+       if (nsize == 0) {
+         free(ptr);
+         return NULL;
+       }
+       else
+         return realloc(ptr, nsize);
+     }
+</pre><p>
+Note that Standard&nbsp;C ensures
+that <code>free(NULL)</code> has no effect and that
+<code>realloc(NULL,size)</code> is equivalent to <code>malloc(size)</code>.
+
+
+
+
+
+<hr><h3><a name="lua_arith"><code>lua_arith</code></a></h3><p>
+<span class="apii">[-(2|1), +1, <em>e</em>]</span>
+<pre>void lua_arith (lua_State *L, int op);</pre>
+
+<p>
+Performs an arithmetic or bitwise operation over the two values
+(or one, in the case of negations)
+at the top of the stack,
+with the value on the top being the second operand,
+pops these values, and pushes the result of the operation.
+The function follows the semantics of the corresponding Lua operator
+(that is, it may call metamethods).
+
+
+<p>
+The value of <code>op</code> must be one of the following constants:
+
+<ul>
+
+<li><b><a name="pdf-LUA_OPADD"><code>LUA_OPADD</code></a>: </b> performs addition (<code>+</code>)</li>
+<li><b><a name="pdf-LUA_OPSUB"><code>LUA_OPSUB</code></a>: </b> performs subtraction (<code>-</code>)</li>
+<li><b><a name="pdf-LUA_OPMUL"><code>LUA_OPMUL</code></a>: </b> performs multiplication (<code>*</code>)</li>
+<li><b><a name="pdf-LUA_OPDIV"><code>LUA_OPDIV</code></a>: </b> performs float division (<code>/</code>)</li>
+<li><b><a name="pdf-LUA_OPIDIV"><code>LUA_OPIDIV</code></a>: </b> performs floor division (<code>//</code>)</li>
+<li><b><a name="pdf-LUA_OPMOD"><code>LUA_OPMOD</code></a>: </b> performs modulo (<code>%</code>)</li>
+<li><b><a name="pdf-LUA_OPPOW"><code>LUA_OPPOW</code></a>: </b> performs exponentiation (<code>^</code>)</li>
+<li><b><a name="pdf-LUA_OPUNM"><code>LUA_OPUNM</code></a>: </b> performs mathematical negation (unary <code>-</code>)</li>
+<li><b><a name="pdf-LUA_OPBNOT"><code>LUA_OPBNOT</code></a>: </b> performs bitwise NOT (<code>~</code>)</li>
+<li><b><a name="pdf-LUA_OPBAND"><code>LUA_OPBAND</code></a>: </b> performs bitwise AND (<code>&amp;</code>)</li>
+<li><b><a name="pdf-LUA_OPBOR"><code>LUA_OPBOR</code></a>: </b> performs bitwise OR (<code>|</code>)</li>
+<li><b><a name="pdf-LUA_OPBXOR"><code>LUA_OPBXOR</code></a>: </b> performs bitwise exclusive OR (<code>~</code>)</li>
+<li><b><a name="pdf-LUA_OPSHL"><code>LUA_OPSHL</code></a>: </b> performs left shift (<code>&lt;&lt;</code>)</li>
+<li><b><a name="pdf-LUA_OPSHR"><code>LUA_OPSHR</code></a>: </b> performs right shift (<code>&gt;&gt;</code>)</li>
+
+</ul>
+
+
+
+
+<hr><h3><a name="lua_atpanic"><code>lua_atpanic</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>lua_CFunction lua_atpanic (lua_State *L, lua_CFunction panicf);</pre>
+
+<p>
+Sets a new panic function and returns the old one (see <a href="#4.4">&sect;4.4</a>).
+
+
+
+
+
+<hr><h3><a name="lua_call"><code>lua_call</code></a></h3><p>
+<span class="apii">[-(nargs+1), +nresults, <em>e</em>]</span>
+<pre>void lua_call (lua_State *L, int nargs, int nresults);</pre>
+
+<p>
+Calls a function.
+Like regular Lua calls,
+<code>lua_call</code> respects the <code>__call</code> metamethod.
+So, here the word "function"
+means any callable value.
+
+
+<p>
+To do a call you must use the following protocol:
+first, the function to be called is pushed onto the stack;
+then, the arguments to the call are pushed
+in direct order;
+that is, the first argument is pushed first.
+Finally you call <a href="#lua_call"><code>lua_call</code></a>;
+<code>nargs</code> is the number of arguments that you pushed onto the stack.
+When the function returns,
+all arguments and the function value are popped
+and the call results are pushed onto the stack.
+The number of results is adjusted to <code>nresults</code>,
+unless <code>nresults</code> is <a name="pdf-LUA_MULTRET"><code>LUA_MULTRET</code></a>.
+In this case, all results from the function are pushed;
+Lua takes care that the returned values fit into the stack space,
+but it does not ensure any extra space in the stack.
+The function results are pushed onto the stack in direct order
+(the first result is pushed first),
+so that after the call the last result is on the top of the stack.
+
+
+<p>
+Any error while calling and running the function is propagated upwards
+(with a <code>longjmp</code>).
+
+
+<p>
+The following example shows how the host program can do the
+equivalent to this Lua code:
+
+<pre>
+     a = f("how", t.x, 14)
+</pre><p>
+Here it is in&nbsp;C:
+
+<pre>
+     lua_getglobal(L, "f");                  /* function to be called */
+     lua_pushliteral(L, "how");                       /* 1st argument */
+     lua_getglobal(L, "t");                    /* table to be indexed */
+     lua_getfield(L, -1, "x");        /* push result of t.x (2nd arg) */
+     lua_remove(L, -2);                  /* remove 't' from the stack */
+     lua_pushinteger(L, 14);                          /* 3rd argument */
+     lua_call(L, 3, 1);     /* call 'f' with 3 arguments and 1 result */
+     lua_setglobal(L, "a");                         /* set global 'a' */
+</pre><p>
+Note that the code above is <em>balanced</em>:
+at its end, the stack is back to its original configuration.
+This is considered good programming practice.
+
+
+
+
+
+<hr><h3><a name="lua_callk"><code>lua_callk</code></a></h3><p>
+<span class="apii">[-(nargs + 1), +nresults, <em>e</em>]</span>
+<pre>void lua_callk (lua_State *L,
+                int nargs,
+                int nresults,
+                lua_KContext ctx,
+                lua_KFunction k);</pre>
+
+<p>
+This function behaves exactly like <a href="#lua_call"><code>lua_call</code></a>,
+but allows the called function to yield (see <a href="#4.5">&sect;4.5</a>).
+
+
+
+
+
+<hr><h3><a name="lua_CFunction"><code>lua_CFunction</code></a></h3>
+<pre>typedef int (*lua_CFunction) (lua_State *L);</pre>
+
+<p>
+Type for C&nbsp;functions.
+
+
+<p>
+In order to communicate properly with Lua,
+a C&nbsp;function must use the following protocol,
+which defines the way parameters and results are passed:
+a C&nbsp;function receives its arguments from Lua in its stack
+in direct order (the first argument is pushed first).
+So, when the function starts,
+<code>lua_gettop(L)</code> returns the number of arguments received by the function.
+The first argument (if any) is at index 1
+and its last argument is at index <code>lua_gettop(L)</code>.
+To return values to Lua, a C&nbsp;function just pushes them onto the stack,
+in direct order (the first result is pushed first),
+and returns in C the number of results.
+Any other value in the stack below the results will be properly
+discarded by Lua.
+Like a Lua function, a C&nbsp;function called by Lua can also return
+many results.
+
+
+<p>
+As an example, the following function receives a variable number
+of numeric arguments and returns their average and their sum:
+
+<pre>
+     static int foo (lua_State *L) {
+       int n = lua_gettop(L);    /* number of arguments */
+       lua_Number sum = 0.0;
+       int i;
+       for (i = 1; i &lt;= n; i++) {
+         if (!lua_isnumber(L, i)) {
+           lua_pushliteral(L, "incorrect argument");
+           lua_error(L);
+         }
+         sum += lua_tonumber(L, i);
+       }
+       lua_pushnumber(L, sum/n);        /* first result */
+       lua_pushnumber(L, sum);         /* second result */
+       return 2;                   /* number of results */
+     }
+</pre>
+
+
+
+
+<hr><h3><a name="lua_checkstack"><code>lua_checkstack</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>int lua_checkstack (lua_State *L, int n);</pre>
+
+<p>
+Ensures that the stack has space for at least <code>n</code> extra slots,
+that is, that you can safely push up to <code>n</code> values into it.
+It returns false if it cannot fulfill the request,
+either because it would cause the stack
+to be greater than a fixed maximum size
+(typically at least several thousand elements) or
+because it cannot allocate memory for the extra space.
+This function never shrinks the stack;
+if the stack already has space for the extra slots,
+it is left unchanged.
+
+
+
+
+
+<hr><h3><a name="lua_close"><code>lua_close</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>void lua_close (lua_State *L);</pre>
+
+<p>
+Close all active to-be-closed variables in the main thread,
+release all objects in the given Lua state
+(calling the corresponding garbage-collection metamethods, if any),
+and frees all dynamic memory used by this state.
+
+
+<p>
+On several platforms, you may not need to call this function,
+because all resources are naturally released when the host program ends.
+On the other hand, long-running programs that create multiple states,
+such as daemons or web servers,
+will probably need to close states as soon as they are not needed.
+
+
+
+
+
+<hr><h3><a name="lua_compare"><code>lua_compare</code></a></h3><p>
+<span class="apii">[-0, +0, <em>e</em>]</span>
+<pre>int lua_compare (lua_State *L, int index1, int index2, int op);</pre>
+
+<p>
+Compares two Lua values.
+Returns 1 if the value at index <code>index1</code> satisfies <code>op</code>
+when compared with the value at index <code>index2</code>,
+following the semantics of the corresponding Lua operator
+(that is, it may call metamethods).
+Otherwise returns&nbsp;0.
+Also returns&nbsp;0 if any of the indices is not valid.
+
+
+<p>
+The value of <code>op</code> must be one of the following constants:
+
+<ul>
+
+<li><b><a name="pdf-LUA_OPEQ"><code>LUA_OPEQ</code></a>: </b> compares for equality (<code>==</code>)</li>
+<li><b><a name="pdf-LUA_OPLT"><code>LUA_OPLT</code></a>: </b> compares for less than (<code>&lt;</code>)</li>
+<li><b><a name="pdf-LUA_OPLE"><code>LUA_OPLE</code></a>: </b> compares for less or equal (<code>&lt;=</code>)</li>
+
+</ul>
+
+
+
+
+<hr><h3><a name="lua_concat"><code>lua_concat</code></a></h3><p>
+<span class="apii">[-n, +1, <em>e</em>]</span>
+<pre>void lua_concat (lua_State *L, int n);</pre>
+
+<p>
+Concatenates the <code>n</code> values at the top of the stack,
+pops them, and leaves the result on the top.
+If <code>n</code>&nbsp;is&nbsp;1, the result is the single value on the stack
+(that is, the function does nothing);
+if <code>n</code> is 0, the result is the empty string.
+Concatenation is performed following the usual semantics of Lua
+(see <a href="#3.4.6">&sect;3.4.6</a>).
+
+
+
+
+
+<hr><h3><a name="lua_copy"><code>lua_copy</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>void lua_copy (lua_State *L, int fromidx, int toidx);</pre>
+
+<p>
+Copies the element at index <code>fromidx</code>
+into the valid index <code>toidx</code>,
+replacing the value at that position.
+Values at other positions are not affected.
+
+
+
+
+
+<hr><h3><a name="lua_createtable"><code>lua_createtable</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>void lua_createtable (lua_State *L, int narr, int nrec);</pre>
+
+<p>
+Creates a new empty table and pushes it onto the stack.
+Parameter <code>narr</code> is a hint for how many elements the table
+will have as a sequence;
+parameter <code>nrec</code> is a hint for how many other elements
+the table will have.
+Lua may use these hints to preallocate memory for the new table.
+This preallocation may help performance when you know in advance
+how many elements the table will have.
+Otherwise you can use the function <a href="#lua_newtable"><code>lua_newtable</code></a>.
+
+
+
+
+
+<hr><h3><a name="lua_dump"><code>lua_dump</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>int lua_dump (lua_State *L,
+                        lua_Writer writer,
+                        void *data,
+                        int strip);</pre>
+
+<p>
+Dumps a function as a binary chunk.
+Receives a Lua function on the top of the stack
+and produces a binary chunk that,
+if loaded again,
+results in a function equivalent to the one dumped.
+As it produces parts of the chunk,
+<a href="#lua_dump"><code>lua_dump</code></a> calls function <code>writer</code> (see <a href="#lua_Writer"><code>lua_Writer</code></a>)
+with the given <code>data</code>
+to write them.
+
+
+<p>
+If <code>strip</code> is true,
+the binary representation may not include all debug information
+about the function,
+to save space.
+
+
+<p>
+The value returned is the error code returned by the last
+call to the writer;
+0&nbsp;means no errors.
+
+
+<p>
+This function does not pop the Lua function from the stack.
+
+
+
+
+
+<hr><h3><a name="lua_error"><code>lua_error</code></a></h3><p>
+<span class="apii">[-1, +0, <em>v</em>]</span>
+<pre>int lua_error (lua_State *L);</pre>
+
+<p>
+Raises a Lua error,
+using the value on the top of the stack as the error object.
+This function does a long jump,
+and therefore never returns
+(see <a href="#luaL_error"><code>luaL_error</code></a>).
+
+
+
+
+
+<hr><h3><a name="lua_gc"><code>lua_gc</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>int lua_gc (lua_State *L, int what, ...);</pre>
+
+<p>
+Controls the garbage collector.
+
+
+<p>
+This function performs several tasks,
+according to the value of the parameter <code>what</code>.
+For options that need extra arguments,
+they are listed after the option.
+
+<ul>
+
+<li><b><code>LUA_GCCOLLECT</code>: </b>
+Performs a full garbage-collection cycle.
+</li>
+
+<li><b><code>LUA_GCSTOP</code>: </b>
+Stops the garbage collector.
+</li>
+
+<li><b><code>LUA_GCRESTART</code>: </b>
+Restarts the garbage collector.
+</li>
+
+<li><b><code>LUA_GCCOUNT</code>: </b>
+Returns the current amount of memory (in Kbytes) in use by Lua.
+</li>
+
+<li><b><code>LUA_GCCOUNTB</code>: </b>
+Returns the remainder of dividing the current amount of bytes of
+memory in use by Lua by 1024.
+</li>
+
+<li><b><code>LUA_GCSTEP</code> <code>(int stepsize)</code>: </b>
+Performs an incremental step of garbage collection,
+corresponding to the allocation of <code>stepsize</code> Kbytes.
+</li>
+
+<li><b><code>LUA_GCISRUNNING</code>: </b>
+Returns a boolean that tells whether the collector is running
+(i.e., not stopped).
+</li>
+
+<li><b><code>LUA_GCINC</code> (int pause, int stepmul, stepsize): </b>
+Changes the collector to incremental mode
+with the given parameters (see <a href="#2.5.1">&sect;2.5.1</a>).
+Returns the previous mode (<code>LUA_GCGEN</code> or <code>LUA_GCINC</code>).
+</li>
+
+<li><b><code>LUA_GCGEN</code> (int minormul, int majormul): </b>
+Changes the collector to generational mode
+with the given parameters (see <a href="#2.5.2">&sect;2.5.2</a>).
+Returns the previous mode (<code>LUA_GCGEN</code> or <code>LUA_GCINC</code>).
+</li>
+
+</ul><p>
+For more details about these options,
+see <a href="#pdf-collectgarbage"><code>collectgarbage</code></a>.
+
+
+
+
+
+<hr><h3><a name="lua_getallocf"><code>lua_getallocf</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>lua_Alloc lua_getallocf (lua_State *L, void **ud);</pre>
+
+<p>
+Returns the memory-allocation function of a given state.
+If <code>ud</code> is not <code>NULL</code>, Lua stores in <code>*ud</code> the
+opaque pointer given when the memory-allocator function was set.
+
+
+
+
+
+<hr><h3><a name="lua_getfield"><code>lua_getfield</code></a></h3><p>
+<span class="apii">[-0, +1, <em>e</em>]</span>
+<pre>int lua_getfield (lua_State *L, int index, const char *k);</pre>
+
+<p>
+Pushes onto the stack the value <code>t[k]</code>,
+where <code>t</code> is the value at the given index.
+As in Lua, this function may trigger a metamethod
+for the "index" event (see <a href="#2.4">&sect;2.4</a>).
+
+
+<p>
+Returns the type of the pushed value.
+
+
+
+
+
+<hr><h3><a name="lua_getextraspace"><code>lua_getextraspace</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>void *lua_getextraspace (lua_State *L);</pre>
+
+<p>
+Returns a pointer to a raw memory area associated with the
+given Lua state.
+The application can use this area for any purpose;
+Lua does not use it for anything.
+
+
+<p>
+Each new thread has this area initialized with a copy
+of the area of the main thread.
+
+
+<p>
+By default, this area has the size of a pointer to void,
+but you can recompile Lua with a different size for this area.
+(See <code>LUA_EXTRASPACE</code> in <code>luaconf.h</code>.)
+
+
+
+
+
+<hr><h3><a name="lua_getglobal"><code>lua_getglobal</code></a></h3><p>
+<span class="apii">[-0, +1, <em>e</em>]</span>
+<pre>int lua_getglobal (lua_State *L, const char *name);</pre>
+
+<p>
+Pushes onto the stack the value of the global <code>name</code>.
+Returns the type of that value.
+
+
+
+
+
+<hr><h3><a name="lua_geti"><code>lua_geti</code></a></h3><p>
+<span class="apii">[-0, +1, <em>e</em>]</span>
+<pre>int lua_geti (lua_State *L, int index, lua_Integer i);</pre>
+
+<p>
+Pushes onto the stack the value <code>t[i]</code>,
+where <code>t</code> is the value at the given index.
+As in Lua, this function may trigger a metamethod
+for the "index" event (see <a href="#2.4">&sect;2.4</a>).
+
+
+<p>
+Returns the type of the pushed value.
+
+
+
+
+
+<hr><h3><a name="lua_getmetatable"><code>lua_getmetatable</code></a></h3><p>
+<span class="apii">[-0, +(0|1), &ndash;]</span>
+<pre>int lua_getmetatable (lua_State *L, int index);</pre>
+
+<p>
+If the value at the given index has a metatable,
+the function pushes that metatable onto the stack and returns&nbsp;1.
+Otherwise,
+the function returns&nbsp;0 and pushes nothing on the stack.
+
+
+
+
+
+<hr><h3><a name="lua_gettable"><code>lua_gettable</code></a></h3><p>
+<span class="apii">[-1, +1, <em>e</em>]</span>
+<pre>int lua_gettable (lua_State *L, int index);</pre>
+
+<p>
+Pushes onto the stack the value <code>t[k]</code>,
+where <code>t</code> is the value at the given index
+and <code>k</code> is the value on the top of the stack.
+
+
+<p>
+This function pops the key from the stack,
+pushing the resulting value in its place.
+As in Lua, this function may trigger a metamethod
+for the "index" event (see <a href="#2.4">&sect;2.4</a>).
+
+
+<p>
+Returns the type of the pushed value.
+
+
+
+
+
+<hr><h3><a name="lua_gettop"><code>lua_gettop</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>int lua_gettop (lua_State *L);</pre>
+
+<p>
+Returns the index of the top element in the stack.
+Because indices start at&nbsp;1,
+this result is equal to the number of elements in the stack;
+in particular, 0&nbsp;means an empty stack.
+
+
+
+
+
+<hr><h3><a name="lua_getiuservalue"><code>lua_getiuservalue</code></a></h3><p>
+<span class="apii">[-0, +1, &ndash;]</span>
+<pre>int lua_getiuservalue (lua_State *L, int index, int n);</pre>
+
+<p>
+Pushes onto the stack the <code>n</code>-th user value associated with the
+full userdata at the given index and
+returns the type of the pushed value.
+
+
+<p>
+If the userdata does not have that value,
+pushes <b>nil</b> and returns <a href="#pdf-LUA_TNONE"><code>LUA_TNONE</code></a>.
+
+
+
+
+
+<hr><h3><a name="lua_insert"><code>lua_insert</code></a></h3><p>
+<span class="apii">[-1, +1, &ndash;]</span>
+<pre>void lua_insert (lua_State *L, int index);</pre>
+
+<p>
+Moves the top element into the given valid index,
+shifting up the elements above this index to open space.
+This function cannot be called with a pseudo-index,
+because a pseudo-index is not an actual stack position.
+
+
+
+
+
+<hr><h3><a name="lua_Integer"><code>lua_Integer</code></a></h3>
+<pre>typedef ... lua_Integer;</pre>
+
+<p>
+The type of integers in Lua.
+
+
+<p>
+By default this type is <code>long long</code>,
+(usually a 64-bit two-complement integer),
+but that can be changed to <code>long</code> or <code>int</code>
+(usually a 32-bit two-complement integer).
+(See <code>LUA_INT_TYPE</code> in <code>luaconf.h</code>.)
+
+
+<p>
+Lua also defines the constants
+<a name="pdf-LUA_MININTEGER"><code>LUA_MININTEGER</code></a> and <a name="pdf-LUA_MAXINTEGER"><code>LUA_MAXINTEGER</code></a>,
+with the minimum and the maximum values that fit in this type.
+
+
+
+
+
+<hr><h3><a name="lua_isboolean"><code>lua_isboolean</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>int lua_isboolean (lua_State *L, int index);</pre>
+
+<p>
+Returns 1 if the value at the given index is a boolean,
+and 0&nbsp;otherwise.
+
+
+
+
+
+<hr><h3><a name="lua_iscfunction"><code>lua_iscfunction</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>int lua_iscfunction (lua_State *L, int index);</pre>
+
+<p>
+Returns 1 if the value at the given index is a C&nbsp;function,
+and 0&nbsp;otherwise.
+
+
+
+
+
+<hr><h3><a name="lua_isfunction"><code>lua_isfunction</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>int lua_isfunction (lua_State *L, int index);</pre>
+
+<p>
+Returns 1 if the value at the given index is a function
+(either C or Lua), and 0&nbsp;otherwise.
+
+
+
+
+
+<hr><h3><a name="lua_isinteger"><code>lua_isinteger</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>int lua_isinteger (lua_State *L, int index);</pre>
+
+<p>
+Returns 1 if the value at the given index is an integer
+(that is, the value is a number and is represented as an integer),
+and 0&nbsp;otherwise.
+
+
+
+
+
+<hr><h3><a name="lua_islightuserdata"><code>lua_islightuserdata</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>int lua_islightuserdata (lua_State *L, int index);</pre>
+
+<p>
+Returns 1 if the value at the given index is a light userdata,
+and 0&nbsp;otherwise.
+
+
+
+
+
+<hr><h3><a name="lua_isnil"><code>lua_isnil</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>int lua_isnil (lua_State *L, int index);</pre>
+
+<p>
+Returns 1 if the value at the given index is <b>nil</b>,
+and 0&nbsp;otherwise.
+
+
+
+
+
+<hr><h3><a name="lua_isnone"><code>lua_isnone</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>int lua_isnone (lua_State *L, int index);</pre>
+
+<p>
+Returns 1 if the given index is not valid,
+and 0&nbsp;otherwise.
+
+
+
+
+
+<hr><h3><a name="lua_isnoneornil"><code>lua_isnoneornil</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>int lua_isnoneornil (lua_State *L, int index);</pre>
+
+<p>
+Returns 1 if the given index is not valid
+or if the value at this index is <b>nil</b>,
+and 0&nbsp;otherwise.
+
+
+
+
+
+<hr><h3><a name="lua_isnumber"><code>lua_isnumber</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>int lua_isnumber (lua_State *L, int index);</pre>
+
+<p>
+Returns 1 if the value at the given index is a number
+or a string convertible to a number,
+and 0&nbsp;otherwise.
+
+
+
+
+
+<hr><h3><a name="lua_isstring"><code>lua_isstring</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>int lua_isstring (lua_State *L, int index);</pre>
+
+<p>
+Returns 1 if the value at the given index is a string
+or a number (which is always convertible to a string),
+and 0&nbsp;otherwise.
+
+
+
+
+
+<hr><h3><a name="lua_istable"><code>lua_istable</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>int lua_istable (lua_State *L, int index);</pre>
+
+<p>
+Returns 1 if the value at the given index is a table,
+and 0&nbsp;otherwise.
+
+
+
+
+
+<hr><h3><a name="lua_isthread"><code>lua_isthread</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>int lua_isthread (lua_State *L, int index);</pre>
+
+<p>
+Returns 1 if the value at the given index is a thread,
+and 0&nbsp;otherwise.
+
+
+
+
+
+<hr><h3><a name="lua_isuserdata"><code>lua_isuserdata</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>int lua_isuserdata (lua_State *L, int index);</pre>
+
+<p>
+Returns 1 if the value at the given index is a userdata
+(either full or light), and 0&nbsp;otherwise.
+
+
+
+
+
+<hr><h3><a name="lua_isyieldable"><code>lua_isyieldable</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>int lua_isyieldable (lua_State *L);</pre>
+
+<p>
+Returns 1 if the given coroutine can yield,
+and 0&nbsp;otherwise.
+
+
+
+
+
+<hr><h3><a name="lua_KContext"><code>lua_KContext</code></a></h3>
+<pre>typedef ... lua_KContext;</pre>
+
+<p>
+The type for continuation-function contexts.
+It must be a numeric type.
+This type is defined as <code>intptr_t</code>
+when <code>intptr_t</code> is available,
+so that it can store pointers too.
+Otherwise, it is defined as <code>ptrdiff_t</code>.
+
+
+
+
+
+<hr><h3><a name="lua_KFunction"><code>lua_KFunction</code></a></h3>
+<pre>typedef int (*lua_KFunction) (lua_State *L, int status, lua_KContext ctx);</pre>
+
+<p>
+Type for continuation functions (see <a href="#4.5">&sect;4.5</a>).
+
+
+
+
+
+<hr><h3><a name="lua_len"><code>lua_len</code></a></h3><p>
+<span class="apii">[-0, +1, <em>e</em>]</span>
+<pre>void lua_len (lua_State *L, int index);</pre>
+
+<p>
+Returns the length of the value at the given index.
+It is equivalent to the '<code>#</code>' operator in Lua (see <a href="#3.4.7">&sect;3.4.7</a>) and
+may trigger a metamethod for the "length" event (see <a href="#2.4">&sect;2.4</a>).
+The result is pushed on the stack.
+
+
+
+
+
+<hr><h3><a name="lua_load"><code>lua_load</code></a></h3><p>
+<span class="apii">[-0, +1, &ndash;]</span>
+<pre>int lua_load (lua_State *L,
+              lua_Reader reader,
+              void *data,
+              const char *chunkname,
+              const char *mode);</pre>
+
+<p>
+Loads a Lua chunk without running it.
+If there are no errors,
+<code>lua_load</code> pushes the compiled chunk as a Lua
+function on top of the stack.
+Otherwise, it pushes an error message.
+
+
+<p>
+The <code>lua_load</code> function uses a user-supplied <code>reader</code> function
+to read the chunk (see <a href="#lua_Reader"><code>lua_Reader</code></a>).
+The <code>data</code> argument is an opaque value passed to the reader function.
+
+
+<p>
+The <code>chunkname</code> argument gives a name to the chunk,
+which is used for error messages and in debug information (see <a href="#4.7">&sect;4.7</a>).
+
+
+<p>
+<code>lua_load</code> automatically detects whether the chunk is text or binary
+and loads it accordingly (see program <code>luac</code>).
+The string <code>mode</code> works as in function <a href="#pdf-load"><code>load</code></a>,
+with the addition that
+a <code>NULL</code> value is equivalent to the string "<code>bt</code>".
+
+
+<p>
+<code>lua_load</code> uses the stack internally,
+so the reader function must always leave the stack
+unmodified when returning.
+
+
+<p>
+<code>lua_load</code> can return
+<a href="#pdf-LUA_OK"><code>LUA_OK</code></a>, <a href="#pdf-LUA_ERRSYNTAX"><code>LUA_ERRSYNTAX</code></a>, or <a href="#pdf-LUA_ERRMEM"><code>LUA_ERRMEM</code></a>.
+The function may also return other values corresponding to
+errors raised by the read function (see <a href="#4.4.1">&sect;4.4.1</a>).
+
+
+<p>
+If the resulting function has upvalues,
+its first upvalue is set to the value of the global environment
+stored at index <code>LUA_RIDX_GLOBALS</code> in the registry (see <a href="#4.3">&sect;4.3</a>).
+When loading main chunks,
+this upvalue will be the <code>_ENV</code> variable (see <a href="#2.2">&sect;2.2</a>).
+Other upvalues are initialized with <b>nil</b>.
+
+
+
+
+
+<hr><h3><a name="lua_newstate"><code>lua_newstate</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>lua_State *lua_newstate (lua_Alloc f, void *ud);</pre>
+
+<p>
+Creates a new independent state and returns its main thread.
+Returns <code>NULL</code> if it cannot create the state
+(due to lack of memory).
+The argument <code>f</code> is the allocator function;
+Lua will do all memory allocation for this state
+through this function (see <a href="#lua_Alloc"><code>lua_Alloc</code></a>).
+The second argument, <code>ud</code>, is an opaque pointer that Lua
+passes to the allocator in every call.
+
+
+
+
+
+<hr><h3><a name="lua_newtable"><code>lua_newtable</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>void lua_newtable (lua_State *L);</pre>
+
+<p>
+Creates a new empty table and pushes it onto the stack.
+It is equivalent to <code>lua_createtable(L, 0, 0)</code>.
+
+
+
+
+
+<hr><h3><a name="lua_newthread"><code>lua_newthread</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>lua_State *lua_newthread (lua_State *L);</pre>
+
+<p>
+Creates a new thread, pushes it on the stack,
+and returns a pointer to a <a href="#lua_State"><code>lua_State</code></a> that represents this new thread.
+The new thread returned by this function shares with the original thread
+its global environment,
+but has an independent execution stack.
+
+
+<p>
+Threads are subject to garbage collection,
+like any Lua object.
+
+
+
+
+
+<hr><h3><a name="lua_newuserdatauv"><code>lua_newuserdatauv</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>void *lua_newuserdatauv (lua_State *L, size_t size, int nuvalue);</pre>
+
+<p>
+This function creates and pushes on the stack a new full userdata,
+with <code>nuvalue</code> associated Lua values, called <code>user values</code>,
+plus an associated block of raw memory with <code>size</code> bytes.
+(The user values can be set and read with the functions
+<a href="#lua_setiuservalue"><code>lua_setiuservalue</code></a> and <a href="#lua_getiuservalue"><code>lua_getiuservalue</code></a>.)
+
+
+<p>
+The function returns the address of the block of memory.
+
+
+
+
+
+<hr><h3><a name="lua_next"><code>lua_next</code></a></h3><p>
+<span class="apii">[-1, +(2|0), <em>v</em>]</span>
+<pre>int lua_next (lua_State *L, int index);</pre>
+
+<p>
+Pops a key from the stack,
+and pushes a key&ndash;value pair from the table at the given index,
+the "next" pair after the given key.
+If there are no more elements in the table,
+then <a href="#lua_next"><code>lua_next</code></a> returns 0 and pushes nothing.
+
+
+<p>
+A typical table traversal looks like this:
+
+<pre>
+     /* table is in the stack at index 't' */
+     lua_pushnil(L);  /* first key */
+     while (lua_next(L, t) != 0) {
+       /* uses 'key' (at index -2) and 'value' (at index -1) */
+       printf("%s - %s\n",
+              lua_typename(L, lua_type(L, -2)),
+              lua_typename(L, lua_type(L, -1)));
+       /* removes 'value'; keeps 'key' for next iteration */
+       lua_pop(L, 1);
+     }
+</pre>
+
+<p>
+While traversing a table,
+avoid calling <a href="#lua_tolstring"><code>lua_tolstring</code></a> directly on a key,
+unless you know that the key is actually a string.
+Recall that <a href="#lua_tolstring"><code>lua_tolstring</code></a> may change
+the value at the given index;
+this confuses the next call to <a href="#lua_next"><code>lua_next</code></a>.
+
+
+<p>
+This function may raise an error if the given key
+is neither <b>nil</b> nor present in the table.
+See function <a href="#pdf-next"><code>next</code></a> for the caveats of modifying
+the table during its traversal.
+
+
+
+
+
+<hr><h3><a name="lua_Number"><code>lua_Number</code></a></h3>
+<pre>typedef ... lua_Number;</pre>
+
+<p>
+The type of floats in Lua.
+
+
+<p>
+By default this type is double,
+but that can be changed to a single float or a long double.
+(See <code>LUA_FLOAT_TYPE</code> in <code>luaconf.h</code>.)
+
+
+
+
+
+<hr><h3><a name="lua_numbertointeger"><code>lua_numbertointeger</code></a></h3>
+<pre>int lua_numbertointeger (lua_Number n, lua_Integer *p);</pre>
+
+<p>
+Tries to convert a Lua float to a Lua integer;
+the float <code>n</code> must have an integral value.
+If that value is within the range of Lua integers,
+it is converted to an integer and assigned to <code>*p</code>.
+The macro results in a boolean indicating whether the
+conversion was successful.
+(Note that this range test can be tricky to do
+correctly without this macro, due to rounding.)
+
+
+<p>
+This macro may evaluate its arguments more than once.
+
+
+
+
+
+<hr><h3><a name="lua_pcall"><code>lua_pcall</code></a></h3><p>
+<span class="apii">[-(nargs + 1), +(nresults|1), &ndash;]</span>
+<pre>int lua_pcall (lua_State *L, int nargs, int nresults, int msgh);</pre>
+
+<p>
+Calls a function (or a callable object) in protected mode.
+
+
+<p>
+Both <code>nargs</code> and <code>nresults</code> have the same meaning as
+in <a href="#lua_call"><code>lua_call</code></a>.
+If there are no errors during the call,
+<a href="#lua_pcall"><code>lua_pcall</code></a> behaves exactly like <a href="#lua_call"><code>lua_call</code></a>.
+However, if there is any error,
+<a href="#lua_pcall"><code>lua_pcall</code></a> catches it,
+pushes a single value on the stack (the error object),
+and returns an error code.
+Like <a href="#lua_call"><code>lua_call</code></a>,
+<a href="#lua_pcall"><code>lua_pcall</code></a> always removes the function
+and its arguments from the stack.
+
+
+<p>
+If <code>msgh</code> is 0,
+then the error object returned on the stack
+is exactly the original error object.
+Otherwise, <code>msgh</code> is the stack index of a
+<em>message handler</em>.
+(This index cannot be a pseudo-index.)
+In case of runtime errors,
+this handler will be called with the error object
+and its return value will be the object
+returned on the stack by <a href="#lua_pcall"><code>lua_pcall</code></a>.
+
+
+<p>
+Typically, the message handler is used to add more debug
+information to the error object, such as a stack traceback.
+Such information cannot be gathered after the return of <a href="#lua_pcall"><code>lua_pcall</code></a>,
+since by then the stack has unwound.
+
+
+<p>
+The <a href="#lua_pcall"><code>lua_pcall</code></a> function returns one of the following status codes:
+<a href="#pdf-LUA_OK"><code>LUA_OK</code></a>, <a href="#pdf-LUA_ERRRUN"><code>LUA_ERRRUN</code></a>, <a href="#pdf-LUA_ERRMEM"><code>LUA_ERRMEM</code></a>, or <a href="#pdf-LUA_ERRERR"><code>LUA_ERRERR</code></a>.
+
+
+
+
+
+<hr><h3><a name="lua_pcallk"><code>lua_pcallk</code></a></h3><p>
+<span class="apii">[-(nargs + 1), +(nresults|1), &ndash;]</span>
+<pre>int lua_pcallk (lua_State *L,
+                int nargs,
+                int nresults,
+                int msgh,
+                lua_KContext ctx,
+                lua_KFunction k);</pre>
+
+<p>
+This function behaves exactly like <a href="#lua_pcall"><code>lua_pcall</code></a>,
+except that it allows the called function to yield (see <a href="#4.5">&sect;4.5</a>).
+
+
+
+
+
+<hr><h3><a name="lua_pop"><code>lua_pop</code></a></h3><p>
+<span class="apii">[-n, +0, &ndash;]</span>
+<pre>void lua_pop (lua_State *L, int n);</pre>
+
+<p>
+Pops <code>n</code> elements from the stack.
+
+
+
+
+
+<hr><h3><a name="lua_pushboolean"><code>lua_pushboolean</code></a></h3><p>
+<span class="apii">[-0, +1, &ndash;]</span>
+<pre>void lua_pushboolean (lua_State *L, int b);</pre>
+
+<p>
+Pushes a boolean value with value <code>b</code> onto the stack.
+
+
+
+
+
+<hr><h3><a name="lua_pushcclosure"><code>lua_pushcclosure</code></a></h3><p>
+<span class="apii">[-n, +1, <em>m</em>]</span>
+<pre>void lua_pushcclosure (lua_State *L, lua_CFunction fn, int n);</pre>
+
+<p>
+Pushes a new C&nbsp;closure onto the stack.
+This function receives a pointer to a C&nbsp;function
+and pushes onto the stack a Lua value of type <code>function</code> that,
+when called, invokes the corresponding C&nbsp;function.
+The parameter <code>n</code> tells how many upvalues this function will have
+(see <a href="#4.2">&sect;4.2</a>).
+
+
+<p>
+Any function to be callable by Lua must
+follow the correct protocol to receive its parameters
+and return its results (see <a href="#lua_CFunction"><code>lua_CFunction</code></a>).
+
+
+<p>
+When a C&nbsp;function is created,
+it is possible to associate some values with it,
+the so called upvalues;
+these upvalues are then accessible to the function whenever it is called.
+This association is called a C&nbsp;closure (see <a href="#4.2">&sect;4.2</a>).
+To create a C&nbsp;closure,
+first the initial values for its upvalues must be pushed onto the stack.
+(When there are multiple upvalues, the first value is pushed first.)
+Then <a href="#lua_pushcclosure"><code>lua_pushcclosure</code></a>
+is called to create and push the C&nbsp;function onto the stack,
+with the argument <code>n</code> telling how many values will be
+associated with the function.
+<a href="#lua_pushcclosure"><code>lua_pushcclosure</code></a> also pops these values from the stack.
+
+
+<p>
+The maximum value for <code>n</code> is 255.
+
+
+<p>
+When <code>n</code> is zero,
+this function creates a <em>light C&nbsp;function</em>,
+which is just a pointer to the C&nbsp;function.
+In that case, it never raises a memory error.
+
+
+
+
+
+<hr><h3><a name="lua_pushcfunction"><code>lua_pushcfunction</code></a></h3><p>
+<span class="apii">[-0, +1, &ndash;]</span>
+<pre>void lua_pushcfunction (lua_State *L, lua_CFunction f);</pre>
+
+<p>
+Pushes a C&nbsp;function onto the stack.
+This function is equivalent to <a href="#lua_pushcclosure"><code>lua_pushcclosure</code></a> with no upvalues.
+
+
+
+
+
+<hr><h3><a name="lua_pushfstring"><code>lua_pushfstring</code></a></h3><p>
+<span class="apii">[-0, +1, <em>v</em>]</span>
+<pre>const char *lua_pushfstring (lua_State *L, const char *fmt, ...);</pre>
+
+<p>
+Pushes onto the stack a formatted string
+and returns a pointer to this string.
+It is similar to the ISO&nbsp;C function <code>sprintf</code>,
+but has two important differences.
+First,
+you do not have to allocate space for the result;
+the result is a Lua string and Lua takes care of memory allocation
+(and deallocation, through garbage collection).
+Second,
+the conversion specifiers are quite restricted.
+There are no flags, widths, or precisions.
+The conversion specifiers can only be
+'<code>%%</code>' (inserts the character '<code>%</code>'),
+'<code>%s</code>' (inserts a zero-terminated string, with no size restrictions),
+'<code>%f</code>' (inserts a <a href="#lua_Number"><code>lua_Number</code></a>),
+'<code>%I</code>' (inserts a <a href="#lua_Integer"><code>lua_Integer</code></a>),
+'<code>%p</code>' (inserts a pointer),
+'<code>%d</code>' (inserts an <code>int</code>),
+'<code>%c</code>' (inserts an <code>int</code> as a one-byte character), and
+'<code>%U</code>' (inserts a <code>long int</code> as a UTF-8 byte sequence).
+
+
+<p>
+This function may raise errors due to memory overflow
+or an invalid conversion specifier.
+
+
+
+
+
+<hr><h3><a name="lua_pushglobaltable"><code>lua_pushglobaltable</code></a></h3><p>
+<span class="apii">[-0, +1, &ndash;]</span>
+<pre>void lua_pushglobaltable (lua_State *L);</pre>
+
+<p>
+Pushes the global environment onto the stack.
+
+
+
+
+
+<hr><h3><a name="lua_pushinteger"><code>lua_pushinteger</code></a></h3><p>
+<span class="apii">[-0, +1, &ndash;]</span>
+<pre>void lua_pushinteger (lua_State *L, lua_Integer n);</pre>
+
+<p>
+Pushes an integer with value <code>n</code> onto the stack.
+
+
+
+
+
+<hr><h3><a name="lua_pushlightuserdata"><code>lua_pushlightuserdata</code></a></h3><p>
+<span class="apii">[-0, +1, &ndash;]</span>
+<pre>void lua_pushlightuserdata (lua_State *L, void *p);</pre>
+
+<p>
+Pushes a light userdata onto the stack.
+
+
+<p>
+Userdata represent C&nbsp;values in Lua.
+A <em>light userdata</em> represents a pointer, a <code>void*</code>.
+It is a value (like a number):
+you do not create it, it has no individual metatable,
+and it is not collected (as it was never created).
+A light userdata is equal to "any"
+light userdata with the same C&nbsp;address.
+
+
+
+
+
+<hr><h3><a name="lua_pushliteral"><code>lua_pushliteral</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>const char *lua_pushliteral (lua_State *L, const char *s);</pre>
+
+<p>
+This macro is equivalent to <a href="#lua_pushstring"><code>lua_pushstring</code></a>,
+but should be used only when <code>s</code> is a literal string.
+(Lua may optimize this case.)
+
+
+
+
+
+<hr><h3><a name="lua_pushlstring"><code>lua_pushlstring</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>const char *lua_pushlstring (lua_State *L, const char *s, size_t len);</pre>
+
+<p>
+Pushes the string pointed to by <code>s</code> with size <code>len</code>
+onto the stack.
+Lua will make or reuse an internal copy of the given string,
+so the memory at <code>s</code> can be freed or reused immediately after
+the function returns.
+The string can contain any binary data,
+including embedded zeros.
+
+
+<p>
+Returns a pointer to the internal copy of the string.
+
+
+
+
+
+<hr><h3><a name="lua_pushnil"><code>lua_pushnil</code></a></h3><p>
+<span class="apii">[-0, +1, &ndash;]</span>
+<pre>void lua_pushnil (lua_State *L);</pre>
+
+<p>
+Pushes a nil value onto the stack.
+
+
+
+
+
+<hr><h3><a name="lua_pushnumber"><code>lua_pushnumber</code></a></h3><p>
+<span class="apii">[-0, +1, &ndash;]</span>
+<pre>void lua_pushnumber (lua_State *L, lua_Number n);</pre>
+
+<p>
+Pushes a float with value <code>n</code> onto the stack.
+
+
+
+
+
+<hr><h3><a name="lua_pushstring"><code>lua_pushstring</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>const char *lua_pushstring (lua_State *L, const char *s);</pre>
+
+<p>
+Pushes the zero-terminated string pointed to by <code>s</code>
+onto the stack.
+Lua will make or reuse an internal copy of the given string,
+so the memory at <code>s</code> can be freed or reused immediately after
+the function returns.
+
+
+<p>
+Returns a pointer to the internal copy of the string.
+
+
+<p>
+If <code>s</code> is <code>NULL</code>, pushes <b>nil</b> and returns <code>NULL</code>.
+
+
+
+
+
+<hr><h3><a name="lua_pushthread"><code>lua_pushthread</code></a></h3><p>
+<span class="apii">[-0, +1, &ndash;]</span>
+<pre>int lua_pushthread (lua_State *L);</pre>
+
+<p>
+Pushes the thread represented by <code>L</code> onto the stack.
+Returns 1 if this thread is the main thread of its state.
+
+
+
+
+
+<hr><h3><a name="lua_pushvalue"><code>lua_pushvalue</code></a></h3><p>
+<span class="apii">[-0, +1, &ndash;]</span>
+<pre>void lua_pushvalue (lua_State *L, int index);</pre>
+
+<p>
+Pushes a copy of the element at the given index
+onto the stack.
+
+
+
+
+
+<hr><h3><a name="lua_pushvfstring"><code>lua_pushvfstring</code></a></h3><p>
+<span class="apii">[-0, +1, <em>v</em>]</span>
+<pre>const char *lua_pushvfstring (lua_State *L,
+                              const char *fmt,
+                              va_list argp);</pre>
+
+<p>
+Equivalent to <a href="#lua_pushfstring"><code>lua_pushfstring</code></a>, except that it receives a <code>va_list</code>
+instead of a variable number of arguments.
+
+
+
+
+
+<hr><h3><a name="lua_rawequal"><code>lua_rawequal</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>int lua_rawequal (lua_State *L, int index1, int index2);</pre>
+
+<p>
+Returns 1 if the two values in indices <code>index1</code> and
+<code>index2</code> are primitively equal
+(that is, equal without calling the <code>__eq</code> metamethod).
+Otherwise returns&nbsp;0.
+Also returns&nbsp;0 if any of the indices are not valid.
+
+
+
+
+
+<hr><h3><a name="lua_rawget"><code>lua_rawget</code></a></h3><p>
+<span class="apii">[-1, +1, &ndash;]</span>
+<pre>int lua_rawget (lua_State *L, int index);</pre>
+
+<p>
+Similar to <a href="#lua_gettable"><code>lua_gettable</code></a>, but does a raw access
+(i.e., without metamethods).
+
+
+
+
+
+<hr><h3><a name="lua_rawgeti"><code>lua_rawgeti</code></a></h3><p>
+<span class="apii">[-0, +1, &ndash;]</span>
+<pre>int lua_rawgeti (lua_State *L, int index, lua_Integer n);</pre>
+
+<p>
+Pushes onto the stack the value <code>t[n]</code>,
+where <code>t</code> is the table at the given index.
+The access is raw,
+that is, it does not use the <code>__index</code> metavalue.
+
+
+<p>
+Returns the type of the pushed value.
+
+
+
+
+
+<hr><h3><a name="lua_rawgetp"><code>lua_rawgetp</code></a></h3><p>
+<span class="apii">[-0, +1, &ndash;]</span>
+<pre>int lua_rawgetp (lua_State *L, int index, const void *p);</pre>
+
+<p>
+Pushes onto the stack the value <code>t[k]</code>,
+where <code>t</code> is the table at the given index and
+<code>k</code> is the pointer <code>p</code> represented as a light userdata.
+The access is raw;
+that is, it does not use the <code>__index</code> metavalue.
+
+
+<p>
+Returns the type of the pushed value.
+
+
+
+
+
+<hr><h3><a name="lua_rawlen"><code>lua_rawlen</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>lua_Unsigned lua_rawlen (lua_State *L, int index);</pre>
+
+<p>
+Returns the raw "length" of the value at the given index:
+for strings, this is the string length;
+for tables, this is the result of the length operator ('<code>#</code>')
+with no metamethods;
+for userdata, this is the size of the block of memory allocated
+for the userdata.
+For other values, this call returns&nbsp;0.
+
+
+
+
+
+<hr><h3><a name="lua_rawset"><code>lua_rawset</code></a></h3><p>
+<span class="apii">[-2, +0, <em>m</em>]</span>
+<pre>void lua_rawset (lua_State *L, int index);</pre>
+
+<p>
+Similar to <a href="#lua_settable"><code>lua_settable</code></a>, but does a raw assignment
+(i.e., without metamethods).
+
+
+
+
+
+<hr><h3><a name="lua_rawseti"><code>lua_rawseti</code></a></h3><p>
+<span class="apii">[-1, +0, <em>m</em>]</span>
+<pre>void lua_rawseti (lua_State *L, int index, lua_Integer i);</pre>
+
+<p>
+Does the equivalent of <code>t[i] = v</code>,
+where <code>t</code> is the table at the given index
+and <code>v</code> is the value on the top of the stack.
+
+
+<p>
+This function pops the value from the stack.
+The assignment is raw,
+that is, it does not use the <code>__newindex</code> metavalue.
+
+
+
+
+
+<hr><h3><a name="lua_rawsetp"><code>lua_rawsetp</code></a></h3><p>
+<span class="apii">[-1, +0, <em>m</em>]</span>
+<pre>void lua_rawsetp (lua_State *L, int index, const void *p);</pre>
+
+<p>
+Does the equivalent of <code>t[p] = v</code>,
+where <code>t</code> is the table at the given index,
+<code>p</code> is encoded as a light userdata,
+and <code>v</code> is the value on the top of the stack.
+
+
+<p>
+This function pops the value from the stack.
+The assignment is raw,
+that is, it does not use the <code>__newindex</code> metavalue.
+
+
+
+
+
+<hr><h3><a name="lua_Reader"><code>lua_Reader</code></a></h3>
+<pre>typedef const char * (*lua_Reader) (lua_State *L,
+                                    void *data,
+                                    size_t *size);</pre>
+
+<p>
+The reader function used by <a href="#lua_load"><code>lua_load</code></a>.
+Every time <a href="#lua_load"><code>lua_load</code></a> needs another piece of the chunk,
+it calls the reader,
+passing along its <code>data</code> parameter.
+The reader must return a pointer to a block of memory
+with a new piece of the chunk
+and set <code>size</code> to the block size.
+The block must exist until the reader function is called again.
+To signal the end of the chunk,
+the reader must return <code>NULL</code> or set <code>size</code> to zero.
+The reader function may return pieces of any size greater than zero.
+
+
+
+
+
+<hr><h3><a name="lua_register"><code>lua_register</code></a></h3><p>
+<span class="apii">[-0, +0, <em>e</em>]</span>
+<pre>void lua_register (lua_State *L, const char *name, lua_CFunction f);</pre>
+
+<p>
+Sets the C&nbsp;function <code>f</code> as the new value of global <code>name</code>.
+It is defined as a macro:
+
+<pre>
+     #define lua_register(L,n,f) \
+            (lua_pushcfunction(L, f), lua_setglobal(L, n))
+</pre>
+
+
+
+
+<hr><h3><a name="lua_remove"><code>lua_remove</code></a></h3><p>
+<span class="apii">[-1, +0, &ndash;]</span>
+<pre>void lua_remove (lua_State *L, int index);</pre>
+
+<p>
+Removes the element at the given valid index,
+shifting down the elements above this index to fill the gap.
+This function cannot be called with a pseudo-index,
+because a pseudo-index is not an actual stack position.
+
+
+
+
+
+<hr><h3><a name="lua_replace"><code>lua_replace</code></a></h3><p>
+<span class="apii">[-1, +0, &ndash;]</span>
+<pre>void lua_replace (lua_State *L, int index);</pre>
+
+<p>
+Moves the top element into the given valid index
+without shifting any element
+(therefore replacing the value at that given index),
+and then pops the top element.
+
+
+
+
+
+<hr><h3><a name="lua_resetthread"><code>lua_resetthread</code></a></h3><p>
+<span class="apii">[-0, +?, &ndash;]</span>
+<pre>int lua_resetthread (lua_State *L);</pre>
+
+<p>
+Resets a thread, cleaning its call stack and closing all pending
+to-be-closed variables.
+Returns a status code:
+<a href="#pdf-LUA_OK"><code>LUA_OK</code></a> for no errors in closing methods,
+or an error status otherwise.
+In case of error,
+leaves the error object on the top of the stack,
+
+
+
+
+
+<hr><h3><a name="lua_resume"><code>lua_resume</code></a></h3><p>
+<span class="apii">[-?, +?, &ndash;]</span>
+<pre>int lua_resume (lua_State *L, lua_State *from, int nargs,
+                          int *nresults);</pre>
+
+<p>
+Starts and resumes a coroutine in the given thread <code>L</code>.
+
+
+<p>
+To start a coroutine,
+you push the main function plus any arguments
+onto the empty stack of the thread.
+then you call <a href="#lua_resume"><code>lua_resume</code></a>,
+with <code>nargs</code> being the number of arguments.
+This call returns when the coroutine suspends or finishes its execution.
+When it returns,
+<code>*nresults</code> is updated and
+the top of the stack contains
+the <code>*nresults</code> values passed to <a href="#lua_yield"><code>lua_yield</code></a>
+or returned by the body function.
+<a href="#lua_resume"><code>lua_resume</code></a> returns
+<a href="#pdf-LUA_YIELD"><code>LUA_YIELD</code></a> if the coroutine yields,
+<a href="#pdf-LUA_OK"><code>LUA_OK</code></a> if the coroutine finishes its execution
+without errors,
+or an error code in case of errors (see <a href="#4.4.1">&sect;4.4.1</a>).
+In case of errors,
+the error object is on the top of the stack.
+
+
+<p>
+To resume a coroutine,
+you remove the <code>*nresults</code> yielded values from its stack,
+push the values to be passed as results from <code>yield</code>,
+and then call <a href="#lua_resume"><code>lua_resume</code></a>.
+
+
+<p>
+The parameter <code>from</code> represents the coroutine that is resuming <code>L</code>.
+If there is no such coroutine,
+this parameter can be <code>NULL</code>.
+
+
+
+
+
+<hr><h3><a name="lua_rotate"><code>lua_rotate</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>void lua_rotate (lua_State *L, int idx, int n);</pre>
+
+<p>
+Rotates the stack elements between the valid index <code>idx</code>
+and the top of the stack.
+The elements are rotated <code>n</code> positions in the direction of the top,
+for a positive <code>n</code>,
+or <code>-n</code> positions in the direction of the bottom,
+for a negative <code>n</code>.
+The absolute value of <code>n</code> must not be greater than the size
+of the slice being rotated.
+This function cannot be called with a pseudo-index,
+because a pseudo-index is not an actual stack position.
+
+
+
+
+
+<hr><h3><a name="lua_setallocf"><code>lua_setallocf</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>void lua_setallocf (lua_State *L, lua_Alloc f, void *ud);</pre>
+
+<p>
+Changes the allocator function of a given state to <code>f</code>
+with user data <code>ud</code>.
+
+
+
+
+
+<hr><h3><a name="lua_setfield"><code>lua_setfield</code></a></h3><p>
+<span class="apii">[-1, +0, <em>e</em>]</span>
+<pre>void lua_setfield (lua_State *L, int index, const char *k);</pre>
+
+<p>
+Does the equivalent to <code>t[k] = v</code>,
+where <code>t</code> is the value at the given index
+and <code>v</code> is the value on the top of the stack.
+
+
+<p>
+This function pops the value from the stack.
+As in Lua, this function may trigger a metamethod
+for the "newindex" event (see <a href="#2.4">&sect;2.4</a>).
+
+
+
+
+
+<hr><h3><a name="lua_setglobal"><code>lua_setglobal</code></a></h3><p>
+<span class="apii">[-1, +0, <em>e</em>]</span>
+<pre>void lua_setglobal (lua_State *L, const char *name);</pre>
+
+<p>
+Pops a value from the stack and
+sets it as the new value of global <code>name</code>.
+
+
+
+
+
+<hr><h3><a name="lua_seti"><code>lua_seti</code></a></h3><p>
+<span class="apii">[-1, +0, <em>e</em>]</span>
+<pre>void lua_seti (lua_State *L, int index, lua_Integer n);</pre>
+
+<p>
+Does the equivalent to <code>t[n] = v</code>,
+where <code>t</code> is the value at the given index
+and <code>v</code> is the value on the top of the stack.
+
+
+<p>
+This function pops the value from the stack.
+As in Lua, this function may trigger a metamethod
+for the "newindex" event (see <a href="#2.4">&sect;2.4</a>).
+
+
+
+
+
+<hr><h3><a name="lua_setiuservalue"><code>lua_setiuservalue</code></a></h3><p>
+<span class="apii">[-1, +0, &ndash;]</span>
+<pre>int lua_setiuservalue (lua_State *L, int index, int n);</pre>
+
+<p>
+Pops a value from the stack and sets it as
+the new <code>n</code>-th user value associated to the
+full userdata at the given index.
+Returns 0 if the userdata does not have that value.
+
+
+
+
+
+<hr><h3><a name="lua_setmetatable"><code>lua_setmetatable</code></a></h3><p>
+<span class="apii">[-1, +0, &ndash;]</span>
+<pre>int lua_setmetatable (lua_State *L, int index);</pre>
+
+<p>
+Pops a table or <b>nil</b> from the stack and
+sets that value as the new metatable for the value at the given index.
+(<b>nil</b> means no metatable.)
+
+
+<p>
+(For historical reasons, this function returns an <code>int</code>,
+which now is always 1.)
+
+
+
+
+
+<hr><h3><a name="lua_settable"><code>lua_settable</code></a></h3><p>
+<span class="apii">[-2, +0, <em>e</em>]</span>
+<pre>void lua_settable (lua_State *L, int index);</pre>
+
+<p>
+Does the equivalent to <code>t[k] = v</code>,
+where <code>t</code> is the value at the given index,
+<code>v</code> is the value on the top of the stack,
+and <code>k</code> is the value just below the top.
+
+
+<p>
+This function pops both the key and the value from the stack.
+As in Lua, this function may trigger a metamethod
+for the "newindex" event (see <a href="#2.4">&sect;2.4</a>).
+
+
+
+
+
+<hr><h3><a name="lua_settop"><code>lua_settop</code></a></h3><p>
+<span class="apii">[-?, +?, &ndash;]</span>
+<pre>void lua_settop (lua_State *L, int index);</pre>
+
+<p>
+Accepts any index, or&nbsp;0,
+and sets the stack top to this index.
+If the new top is greater than the old one,
+then the new elements are filled with <b>nil</b>.
+If <code>index</code> is&nbsp;0, then all stack elements are removed.
+
+
+
+
+
+<hr><h3><a name="lua_setwarnf"><code>lua_setwarnf</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>void lua_setwarnf (lua_State *L, lua_WarnFunction f, void *ud);</pre>
+
+<p>
+Sets the warning function to be used by Lua to emit warnings
+(see <a href="#lua_WarnFunction"><code>lua_WarnFunction</code></a>).
+The <code>ud</code> parameter sets the value <code>ud</code> passed to
+the warning function.
+
+
+
+
+
+<hr><h3><a name="lua_State"><code>lua_State</code></a></h3>
+<pre>typedef struct lua_State lua_State;</pre>
+
+<p>
+An opaque structure that points to a thread and indirectly
+(through the thread) to the whole state of a Lua interpreter.
+The Lua library is fully reentrant:
+it has no global variables.
+All information about a state is accessible through this structure.
+
+
+<p>
+A pointer to this structure must be passed as the first argument to
+every function in the library, except to <a href="#lua_newstate"><code>lua_newstate</code></a>,
+which creates a Lua state from scratch.
+
+
+
+
+
+<hr><h3><a name="lua_status"><code>lua_status</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>int lua_status (lua_State *L);</pre>
+
+<p>
+Returns the status of the thread <code>L</code>.
+
+
+<p>
+The status can be <a href="#pdf-LUA_OK"><code>LUA_OK</code></a> for a normal thread,
+an error code if the thread finished the execution
+of a <a href="#lua_resume"><code>lua_resume</code></a> with an error,
+or <a href="#pdf-LUA_YIELD"><code>LUA_YIELD</code></a> if the thread is suspended.
+
+
+<p>
+You can call functions only in threads with status <a href="#pdf-LUA_OK"><code>LUA_OK</code></a>.
+You can resume threads with status <a href="#pdf-LUA_OK"><code>LUA_OK</code></a>
+(to start a new coroutine) or <a href="#pdf-LUA_YIELD"><code>LUA_YIELD</code></a>
+(to resume a coroutine).
+
+
+
+
+
+<hr><h3><a name="lua_stringtonumber"><code>lua_stringtonumber</code></a></h3><p>
+<span class="apii">[-0, +1, &ndash;]</span>
+<pre>size_t lua_stringtonumber (lua_State *L, const char *s);</pre>
+
+<p>
+Converts the zero-terminated string <code>s</code> to a number,
+pushes that number into the stack,
+and returns the total size of the string,
+that is, its length plus one.
+The conversion can result in an integer or a float,
+according to the lexical conventions of Lua (see <a href="#3.1">&sect;3.1</a>).
+The string may have leading and trailing whitespaces and a sign.
+If the string is not a valid numeral,
+returns 0 and pushes nothing.
+(Note that the result can be used as a boolean,
+true if the conversion succeeds.)
+
+
+
+
+
+<hr><h3><a name="lua_toboolean"><code>lua_toboolean</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>int lua_toboolean (lua_State *L, int index);</pre>
+
+<p>
+Converts the Lua value at the given index to a C&nbsp;boolean
+value (0&nbsp;or&nbsp;1).
+Like all tests in Lua,
+<a href="#lua_toboolean"><code>lua_toboolean</code></a> returns true for any Lua value
+different from <b>false</b> and <b>nil</b>;
+otherwise it returns false.
+(If you want to accept only actual boolean values,
+use <a href="#lua_isboolean"><code>lua_isboolean</code></a> to test the value's type.)
+
+
+
+
+
+<hr><h3><a name="lua_tocfunction"><code>lua_tocfunction</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>lua_CFunction lua_tocfunction (lua_State *L, int index);</pre>
+
+<p>
+Converts a value at the given index to a C&nbsp;function.
+That value must be a C&nbsp;function;
+otherwise, returns <code>NULL</code>.
+
+
+
+
+
+<hr><h3><a name="lua_toclose"><code>lua_toclose</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>void lua_toclose (lua_State *L, int index);</pre>
+
+<p>
+Marks the given index in the stack as a
+to-be-closed "variable" (see <a href="#3.3.8">&sect;3.3.8</a>).
+Like a to-be-closed variable in Lua,
+the value at that index in the stack will be closed
+when it goes out of scope.
+Here, in the context of a C function,
+to go out of scope means that the running function returns to Lua,
+there is an error,
+or the index is removed from the stack through
+<a href="#lua_settop"><code>lua_settop</code></a> or <a href="#lua_pop"><code>lua_pop</code></a>.
+An index marked as to-be-closed should not be removed from the stack
+by any other function in the API except <a href="#lua_settop"><code>lua_settop</code></a> or <a href="#lua_pop"><code>lua_pop</code></a>.
+
+
+<p>
+This function should not be called for an index
+that is equal to or below an active to-be-closed index.
+
+
+<p>
+This function can raise an out-of-memory error.
+In that case, the value in the given index is immediately closed,
+as if it was already marked.
+
+
+
+
+
+<hr><h3><a name="lua_tointeger"><code>lua_tointeger</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>lua_Integer lua_tointeger (lua_State *L, int index);</pre>
+
+<p>
+Equivalent to <a href="#lua_tointegerx"><code>lua_tointegerx</code></a> with <code>isnum</code> equal to <code>NULL</code>.
+
+
+
+
+
+<hr><h3><a name="lua_tointegerx"><code>lua_tointegerx</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>lua_Integer lua_tointegerx (lua_State *L, int index, int *isnum);</pre>
+
+<p>
+Converts the Lua value at the given index
+to the signed integral type <a href="#lua_Integer"><code>lua_Integer</code></a>.
+The Lua value must be an integer,
+or a number or string convertible to an integer (see <a href="#3.4.3">&sect;3.4.3</a>);
+otherwise, <code>lua_tointegerx</code> returns&nbsp;0.
+
+
+<p>
+If <code>isnum</code> is not <code>NULL</code>,
+its referent is assigned a boolean value that
+indicates whether the operation succeeded.
+
+
+
+
+
+<hr><h3><a name="lua_tolstring"><code>lua_tolstring</code></a></h3><p>
+<span class="apii">[-0, +0, <em>m</em>]</span>
+<pre>const char *lua_tolstring (lua_State *L, int index, size_t *len);</pre>
+
+<p>
+Converts the Lua value at the given index to a C&nbsp;string.
+If <code>len</code> is not <code>NULL</code>,
+it sets <code>*len</code> with the string length.
+The Lua value must be a string or a number;
+otherwise, the function returns <code>NULL</code>.
+If the value is a number,
+then <code>lua_tolstring</code> also
+<em>changes the actual value in the stack to a string</em>.
+(This change confuses <a href="#lua_next"><code>lua_next</code></a>
+when <code>lua_tolstring</code> is applied to keys during a table traversal.)
+
+
+<p>
+<code>lua_tolstring</code> returns a pointer
+to a string inside the Lua state.
+This string always has a zero ('<code>\0</code>')
+after its last character (as in&nbsp;C),
+but can contain other zeros in its body.
+
+
+<p>
+Because Lua has garbage collection,
+there is no guarantee that the pointer returned by <code>lua_tolstring</code>
+will be valid after the corresponding Lua value is removed from the stack.
+
+
+
+
+
+<hr><h3><a name="lua_tonumber"><code>lua_tonumber</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>lua_Number lua_tonumber (lua_State *L, int index);</pre>
+
+<p>
+Equivalent to <a href="#lua_tonumberx"><code>lua_tonumberx</code></a> with <code>isnum</code> equal to <code>NULL</code>.
+
+
+
+
+
+<hr><h3><a name="lua_tonumberx"><code>lua_tonumberx</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>lua_Number lua_tonumberx (lua_State *L, int index, int *isnum);</pre>
+
+<p>
+Converts the Lua value at the given index
+to the C&nbsp;type <a href="#lua_Number"><code>lua_Number</code></a> (see <a href="#lua_Number"><code>lua_Number</code></a>).
+The Lua value must be a number or a string convertible to a number
+(see <a href="#3.4.3">&sect;3.4.3</a>);
+otherwise, <a href="#lua_tonumberx"><code>lua_tonumberx</code></a> returns&nbsp;0.
+
+
+<p>
+If <code>isnum</code> is not <code>NULL</code>,
+its referent is assigned a boolean value that
+indicates whether the operation succeeded.
+
+
+
+
+
+<hr><h3><a name="lua_topointer"><code>lua_topointer</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>const void *lua_topointer (lua_State *L, int index);</pre>
+
+<p>
+Converts the value at the given index to a generic
+C&nbsp;pointer (<code>void*</code>).
+The value can be a userdata, a table, a thread, a string, or a function;
+otherwise, <code>lua_topointer</code> returns <code>NULL</code>.
+Different objects will give different pointers.
+There is no way to convert the pointer back to its original value.
+
+
+<p>
+Typically this function is used only for hashing and debug information.
+
+
+
+
+
+<hr><h3><a name="lua_tostring"><code>lua_tostring</code></a></h3><p>
+<span class="apii">[-0, +0, <em>m</em>]</span>
+<pre>const char *lua_tostring (lua_State *L, int index);</pre>
+
+<p>
+Equivalent to <a href="#lua_tolstring"><code>lua_tolstring</code></a> with <code>len</code> equal to <code>NULL</code>.
+
+
+
+
+
+<hr><h3><a name="lua_tothread"><code>lua_tothread</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>lua_State *lua_tothread (lua_State *L, int index);</pre>
+
+<p>
+Converts the value at the given index to a Lua thread
+(represented as <code>lua_State*</code>).
+This value must be a thread;
+otherwise, the function returns <code>NULL</code>.
+
+
+
+
+
+<hr><h3><a name="lua_touserdata"><code>lua_touserdata</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>void *lua_touserdata (lua_State *L, int index);</pre>
+
+<p>
+If the value at the given index is a full userdata,
+returns its memory-block address.
+If the value is a light userdata,
+returns its value (a pointer).
+Otherwise, returns <code>NULL</code>.
+
+
+
+
+
+<hr><h3><a name="lua_type"><code>lua_type</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>int lua_type (lua_State *L, int index);</pre>
+
+<p>
+Returns the type of the value in the given valid index,
+or <code>LUA_TNONE</code> for a non-valid but acceptable index.
+The types returned by <a href="#lua_type"><code>lua_type</code></a> are coded by the following constants
+defined in <code>lua.h</code>:
+<a name="pdf-LUA_TNIL"><code>LUA_TNIL</code></a>,
+<a name="pdf-LUA_TNUMBER"><code>LUA_TNUMBER</code></a>,
+<a name="pdf-LUA_TBOOLEAN"><code>LUA_TBOOLEAN</code></a>,
+<a name="pdf-LUA_TSTRING"><code>LUA_TSTRING</code></a>,
+<a name="pdf-LUA_TTABLE"><code>LUA_TTABLE</code></a>,
+<a name="pdf-LUA_TFUNCTION"><code>LUA_TFUNCTION</code></a>,
+<a name="pdf-LUA_TUSERDATA"><code>LUA_TUSERDATA</code></a>,
+<a name="pdf-LUA_TTHREAD"><code>LUA_TTHREAD</code></a>,
+and
+<a name="pdf-LUA_TLIGHTUSERDATA"><code>LUA_TLIGHTUSERDATA</code></a>.
+
+
+
+
+
+<hr><h3><a name="lua_typename"><code>lua_typename</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>const char *lua_typename (lua_State *L, int tp);</pre>
+
+<p>
+Returns the name of the type encoded by the value <code>tp</code>,
+which must be one the values returned by <a href="#lua_type"><code>lua_type</code></a>.
+
+
+
+
+
+<hr><h3><a name="lua_Unsigned"><code>lua_Unsigned</code></a></h3>
+<pre>typedef ... lua_Unsigned;</pre>
+
+<p>
+The unsigned version of <a href="#lua_Integer"><code>lua_Integer</code></a>.
+
+
+
+
+
+<hr><h3><a name="lua_upvalueindex"><code>lua_upvalueindex</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>int lua_upvalueindex (int i);</pre>
+
+<p>
+Returns the pseudo-index that represents the <code>i</code>-th upvalue of
+the running function (see <a href="#4.2">&sect;4.2</a>).
+<code>i</code> must be in the range <em>[1,256]</em>.
+
+
+
+
+
+<hr><h3><a name="lua_version"><code>lua_version</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>lua_Number lua_version (lua_State *L);</pre>
+
+<p>
+Returns the version number of this core.
+
+
+
+
+
+<hr><h3><a name="lua_WarnFunction"><code>lua_WarnFunction</code></a></h3>
+<pre>typedef void (*lua_WarnFunction) (void *ud, const char *msg, int tocont);</pre>
+
+<p>
+The type of warning functions, called by Lua to emit warnings.
+The first parameter is an opaque pointer
+set by <a href="#lua_setwarnf"><code>lua_setwarnf</code></a>.
+The second parameter is the warning message.
+The third parameter is a boolean that
+indicates whether the message is
+to be continued by the message in the next call.
+
+
+<p>
+See <a href="#pdf-warn"><code>warn</code></a> for more details about warnings.
+
+
+
+
+
+<hr><h3><a name="lua_warning"><code>lua_warning</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>void lua_warning (lua_State *L, const char *msg, int tocont);</pre>
+
+<p>
+Emits a warning with the given message.
+A message in a call with <code>tocont</code> true should be
+continued in another call to this function.
+
+
+<p>
+See <a href="#pdf-warn"><code>warn</code></a> for more details about warnings.
+
+
+
+
+
+<hr><h3><a name="lua_Writer"><code>lua_Writer</code></a></h3>
+<pre>typedef int (*lua_Writer) (lua_State *L,
+                           const void* p,
+                           size_t sz,
+                           void* ud);</pre>
+
+<p>
+The type of the writer function used by <a href="#lua_dump"><code>lua_dump</code></a>.
+Every time <a href="#lua_dump"><code>lua_dump</code></a> produces another piece of chunk,
+it calls the writer,
+passing along the buffer to be written (<code>p</code>),
+its size (<code>sz</code>),
+and the <code>ud</code> parameter supplied to <a href="#lua_dump"><code>lua_dump</code></a>.
+
+
+<p>
+The writer returns an error code:
+0&nbsp;means no errors;
+any other value means an error and stops <a href="#lua_dump"><code>lua_dump</code></a> from
+calling the writer again.
+
+
+
+
+
+<hr><h3><a name="lua_xmove"><code>lua_xmove</code></a></h3><p>
+<span class="apii">[-?, +?, &ndash;]</span>
+<pre>void lua_xmove (lua_State *from, lua_State *to, int n);</pre>
+
+<p>
+Exchange values between different threads of the same state.
+
+
+<p>
+This function pops <code>n</code> values from the stack <code>from</code>,
+and pushes them onto the stack <code>to</code>.
+
+
+
+
+
+<hr><h3><a name="lua_yield"><code>lua_yield</code></a></h3><p>
+<span class="apii">[-?, +?, <em>v</em>]</span>
+<pre>int lua_yield (lua_State *L, int nresults);</pre>
+
+<p>
+This function is equivalent to <a href="#lua_yieldk"><code>lua_yieldk</code></a>,
+but it has no continuation (see <a href="#4.5">&sect;4.5</a>).
+Therefore, when the thread resumes,
+it continues the function that called
+the function calling <code>lua_yield</code>.
+To avoid surprises,
+this function should be called only in a tail call.
+
+
+
+
+
+<hr><h3><a name="lua_yieldk"><code>lua_yieldk</code></a></h3><p>
+<span class="apii">[-?, +?, <em>v</em>]</span>
+<pre>int lua_yieldk (lua_State *L,
+                int nresults,
+                lua_KContext ctx,
+                lua_KFunction k);</pre>
+
+<p>
+Yields a coroutine (thread).
+
+
+<p>
+When a C&nbsp;function calls <a href="#lua_yieldk"><code>lua_yieldk</code></a>,
+the running coroutine suspends its execution,
+and the call to <a href="#lua_resume"><code>lua_resume</code></a> that started this coroutine returns.
+The parameter <code>nresults</code> is the number of values from the stack
+that will be passed as results to <a href="#lua_resume"><code>lua_resume</code></a>.
+
+
+<p>
+When the coroutine is resumed again,
+Lua calls the given continuation function <code>k</code> to continue
+the execution of the C&nbsp;function that yielded (see <a href="#4.5">&sect;4.5</a>).
+This continuation function receives the same stack
+from the previous function,
+with the <code>n</code> results removed and
+replaced by the arguments passed to <a href="#lua_resume"><code>lua_resume</code></a>.
+Moreover,
+the continuation function receives the value <code>ctx</code>
+that was passed to <a href="#lua_yieldk"><code>lua_yieldk</code></a>.
+
+
+<p>
+Usually, this function does not return;
+when the coroutine eventually resumes,
+it continues executing the continuation function.
+However, there is one special case,
+which is when this function is called
+from inside a line or a count hook (see <a href="#4.7">&sect;4.7</a>).
+In that case, <code>lua_yieldk</code> should be called with no continuation
+(probably in the form of <a href="#lua_yield"><code>lua_yield</code></a>) and no results,
+and the hook should return immediately after the call.
+Lua will yield and,
+when the coroutine resumes again,
+it will continue the normal execution
+of the (Lua) function that triggered the hook.
+
+
+<p>
+This function can raise an error if it is called from a thread
+with a pending C call with no continuation function
+(what is called a <em>C-call boundary</em>),
+or it is called from a thread that is not running inside a resume
+(typically the main thread).
+
+
+
+
+
+
+
+<h2>4.7 &ndash; <a name="4.7">The Debug Interface</a></h2>
+
+<p>
+Lua has no built-in debugging facilities.
+Instead, it offers a special interface
+by means of functions and <em>hooks</em>.
+This interface allows the construction of different
+kinds of debuggers, profilers, and other tools
+that need "inside information" from the interpreter.
+
+
+
+<hr><h3><a name="lua_Debug"><code>lua_Debug</code></a></h3>
+<pre>typedef struct lua_Debug {
+  int event;
+  const char *name;           /* (n) */
+  const char *namewhat;       /* (n) */
+  const char *what;           /* (S) */
+  const char *source;         /* (S) */
+  size_t srclen;              /* (S) */
+  int currentline;            /* (l) */
+  int linedefined;            /* (S) */
+  int lastlinedefined;        /* (S) */
+  unsigned char nups;         /* (u) number of upvalues */
+  unsigned char nparams;      /* (u) number of parameters */
+  char isvararg;              /* (u) */
+  char istailcall;            /* (t) */
+  unsigned short ftransfer;   /* (r) index of first value transferred */
+  unsigned short ntransfer;   /* (r) number of transferred values */
+  char short_src[LUA_IDSIZE]; /* (S) */
+  /* private part */
+  <em>other fields</em>
+} lua_Debug;</pre>
+
+<p>
+A structure used to carry different pieces of
+information about a function or an activation record.
+<a href="#lua_getstack"><code>lua_getstack</code></a> fills only the private part
+of this structure, for later use.
+To fill the other fields of <a href="#lua_Debug"><code>lua_Debug</code></a> with useful information,
+you must call <a href="#lua_getinfo"><code>lua_getinfo</code></a>.
+
+
+<p>
+The fields of <a href="#lua_Debug"><code>lua_Debug</code></a> have the following meaning:
+
+<ul>
+
+<li><b><code>source</code>: </b>
+the source of the chunk that created the function.
+If <code>source</code> starts with a '<code>@</code>',
+it means that the function was defined in a file where
+the file name follows the '<code>@</code>'.
+If <code>source</code> starts with a '<code>=</code>',
+the remainder of its contents describes the source in a user-dependent manner.
+Otherwise,
+the function was defined in a string where
+<code>source</code> is that string.
+</li>
+
+<li><b><code>srclen</code>: </b>
+The length of the string <code>source</code>.
+</li>
+
+<li><b><code>short_src</code>: </b>
+a "printable" version of <code>source</code>, to be used in error messages.
+</li>
+
+<li><b><code>linedefined</code>: </b>
+the line number where the definition of the function starts.
+</li>
+
+<li><b><code>lastlinedefined</code>: </b>
+the line number where the definition of the function ends.
+</li>
+
+<li><b><code>what</code>: </b>
+the string <code>"Lua"</code> if the function is a Lua function,
+<code>"C"</code> if it is a C&nbsp;function,
+<code>"main"</code> if it is the main part of a chunk.
+</li>
+
+<li><b><code>currentline</code>: </b>
+the current line where the given function is executing.
+When no line information is available,
+<code>currentline</code> is set to -1.
+</li>
+
+<li><b><code>name</code>: </b>
+a reasonable name for the given function.
+Because functions in Lua are first-class values,
+they do not have a fixed name:
+some functions can be the value of multiple global variables,
+while others can be stored only in a table field.
+The <code>lua_getinfo</code> function checks how the function was
+called to find a suitable name.
+If it cannot find a name,
+then <code>name</code> is set to <code>NULL</code>.
+</li>
+
+<li><b><code>namewhat</code>: </b>
+explains the <code>name</code> field.
+The value of <code>namewhat</code> can be
+<code>"global"</code>, <code>"local"</code>, <code>"method"</code>,
+<code>"field"</code>, <code>"upvalue"</code>, or <code>""</code> (the empty string),
+according to how the function was called.
+(Lua uses the empty string when no other option seems to apply.)
+</li>
+
+<li><b><code>istailcall</code>: </b>
+true if this function invocation was called by a tail call.
+In this case, the caller of this level is not in the stack.
+</li>
+
+<li><b><code>nups</code>: </b>
+the number of upvalues of the function.
+</li>
+
+<li><b><code>nparams</code>: </b>
+the number of parameters of the function
+(always 0&nbsp;for C&nbsp;functions).
+</li>
+
+<li><b><code>isvararg</code>: </b>
+true if the function is a vararg function
+(always true for C&nbsp;functions).
+</li>
+
+<li><b><code>ftransfer</code>: </b>
+the index on the stack of the first value being "transferred",
+that is, parameters in a call or return values in a return.
+(The other values are in consecutive indices.)
+Using this index, you can access and modify these values
+through <a href="#lua_getlocal"><code>lua_getlocal</code></a> and <a href="#lua_setlocal"><code>lua_setlocal</code></a>.
+This field is only meaningful during a
+call hook, denoting the first parameter,
+or a return hook, denoting the first value being returned.
+(For call hooks, this value is always 1.)
+</li>
+
+<li><b><code>ntransfer</code>: </b>
+The number of values being transferred (see previous item).
+(For calls of Lua functions,
+this value is always equal to <code>nparams</code>.)
+</li>
+
+</ul>
+
+
+
+
+<hr><h3><a name="lua_gethook"><code>lua_gethook</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>lua_Hook lua_gethook (lua_State *L);</pre>
+
+<p>
+Returns the current hook function.
+
+
+
+
+
+<hr><h3><a name="lua_gethookcount"><code>lua_gethookcount</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>int lua_gethookcount (lua_State *L);</pre>
+
+<p>
+Returns the current hook count.
+
+
+
+
+
+<hr><h3><a name="lua_gethookmask"><code>lua_gethookmask</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>int lua_gethookmask (lua_State *L);</pre>
+
+<p>
+Returns the current hook mask.
+
+
+
+
+
+<hr><h3><a name="lua_getinfo"><code>lua_getinfo</code></a></h3><p>
+<span class="apii">[-(0|1), +(0|1|2), <em>m</em>]</span>
+<pre>int lua_getinfo (lua_State *L, const char *what, lua_Debug *ar);</pre>
+
+<p>
+Gets information about a specific function or function invocation.
+
+
+<p>
+To get information about a function invocation,
+the parameter <code>ar</code> must be a valid activation record that was
+filled by a previous call to <a href="#lua_getstack"><code>lua_getstack</code></a> or
+given as argument to a hook (see <a href="#lua_Hook"><code>lua_Hook</code></a>).
+
+
+<p>
+To get information about a function, you push it onto the stack
+and start the <code>what</code> string with the character '<code>&gt;</code>'.
+(In that case,
+<code>lua_getinfo</code> pops the function from the top of the stack.)
+For instance, to know in which line a function <code>f</code> was defined,
+you can write the following code:
+
+<pre>
+     lua_Debug ar;
+     lua_getglobal(L, "f");  /* get global 'f' */
+     lua_getinfo(L, "&gt;S", &amp;ar);
+     printf("%d\n", ar.linedefined);
+</pre>
+
+<p>
+Each character in the string <code>what</code>
+selects some fields of the structure <code>ar</code> to be filled or
+a value to be pushed on the stack:
+
+<ul>
+
+<li><b>'<code>n</code>': </b> fills in the field <code>name</code> and <code>namewhat</code>;
+</li>
+
+<li><b>'<code>S</code>': </b>
+fills in the fields <code>source</code>, <code>short_src</code>,
+<code>linedefined</code>, <code>lastlinedefined</code>, and <code>what</code>;
+</li>
+
+<li><b>'<code>l</code>': </b> fills in the field <code>currentline</code>;
+</li>
+
+<li><b>'<code>t</code>': </b> fills in the field <code>istailcall</code>;
+</li>
+
+<li><b>'<code>u</code>': </b> fills in the fields
+<code>nups</code>, <code>nparams</code>, and <code>isvararg</code>;
+</li>
+
+<li><b>'<code>f</code>': </b>
+pushes onto the stack the function that is
+running at the given level;
+</li>
+
+<li><b>'<code>L</code>': </b>
+pushes onto the stack a table whose indices are the
+numbers of the lines that are valid on the function.
+(A <em>valid line</em> is a line with some associated code,
+that is, a line where you can put a break point.
+Non-valid lines include empty lines and comments.)
+
+
+<p>
+If this option is given together with option '<code>f</code>',
+its table is pushed after the function.
+
+
+<p>
+This is the only option that can raise a memory error.
+</li>
+
+</ul>
+
+<p>
+This function returns 0 to signal an invalid option in <code>what</code>;
+even then the valid options are handled correctly.
+
+
+
+
+
+<hr><h3><a name="lua_getlocal"><code>lua_getlocal</code></a></h3><p>
+<span class="apii">[-0, +(0|1), &ndash;]</span>
+<pre>const char *lua_getlocal (lua_State *L, const lua_Debug *ar, int n);</pre>
+
+<p>
+Gets information about a local variable or a temporary value
+of a given activation record or a given function.
+
+
+<p>
+In the first case,
+the parameter <code>ar</code> must be a valid activation record that was
+filled by a previous call to <a href="#lua_getstack"><code>lua_getstack</code></a> or
+given as argument to a hook (see <a href="#lua_Hook"><code>lua_Hook</code></a>).
+The index <code>n</code> selects which local variable to inspect;
+see <a href="#pdf-debug.getlocal"><code>debug.getlocal</code></a> for details about variable indices
+and names.
+
+
+<p>
+<a href="#lua_getlocal"><code>lua_getlocal</code></a> pushes the variable's value onto the stack
+and returns its name.
+
+
+<p>
+In the second case, <code>ar</code> must be <code>NULL</code> and the function
+to be inspected must be on the top of the stack.
+In this case, only parameters of Lua functions are visible
+(as there is no information about what variables are active)
+and no values are pushed onto the stack.
+
+
+<p>
+Returns <code>NULL</code> (and pushes nothing)
+when the index is greater than
+the number of active local variables.
+
+
+
+
+
+<hr><h3><a name="lua_getstack"><code>lua_getstack</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>int lua_getstack (lua_State *L, int level, lua_Debug *ar);</pre>
+
+<p>
+Gets information about the interpreter runtime stack.
+
+
+<p>
+This function fills parts of a <a href="#lua_Debug"><code>lua_Debug</code></a> structure with
+an identification of the <em>activation record</em>
+of the function executing at a given level.
+Level&nbsp;0 is the current running function,
+whereas level <em>n+1</em> is the function that has called level <em>n</em>
+(except for tail calls, which do not count on the stack).
+When called with a level greater than the stack depth,
+<a href="#lua_getstack"><code>lua_getstack</code></a> returns 0;
+otherwise it returns 1.
+
+
+
+
+
+<hr><h3><a name="lua_getupvalue"><code>lua_getupvalue</code></a></h3><p>
+<span class="apii">[-0, +(0|1), &ndash;]</span>
+<pre>const char *lua_getupvalue (lua_State *L, int funcindex, int n);</pre>
+
+<p>
+Gets information about the <code>n</code>-th upvalue
+of the closure at index <code>funcindex</code>.
+It pushes the upvalue's value onto the stack
+and returns its name.
+Returns <code>NULL</code> (and pushes nothing)
+when the index <code>n</code> is greater than the number of upvalues.
+
+
+<p>
+See <a href="#pdf-debug.getupvalue"><code>debug.getupvalue</code></a> for more information about upvalues.
+
+
+
+
+
+<hr><h3><a name="lua_Hook"><code>lua_Hook</code></a></h3>
+<pre>typedef void (*lua_Hook) (lua_State *L, lua_Debug *ar);</pre>
+
+<p>
+Type for debugging hook functions.
+
+
+<p>
+Whenever a hook is called, its <code>ar</code> argument has its field
+<code>event</code> set to the specific event that triggered the hook.
+Lua identifies these events with the following constants:
+<a name="pdf-LUA_HOOKCALL"><code>LUA_HOOKCALL</code></a>, <a name="pdf-LUA_HOOKRET"><code>LUA_HOOKRET</code></a>,
+<a name="pdf-LUA_HOOKTAILCALL"><code>LUA_HOOKTAILCALL</code></a>, <a name="pdf-LUA_HOOKLINE"><code>LUA_HOOKLINE</code></a>,
+and <a name="pdf-LUA_HOOKCOUNT"><code>LUA_HOOKCOUNT</code></a>.
+Moreover, for line events, the field <code>currentline</code> is also set.
+To get the value of any other field in <code>ar</code>,
+the hook must call <a href="#lua_getinfo"><code>lua_getinfo</code></a>.
+
+
+<p>
+For call events, <code>event</code> can be <code>LUA_HOOKCALL</code>,
+the normal value, or <code>LUA_HOOKTAILCALL</code>, for a tail call;
+in this case, there will be no corresponding return event.
+
+
+<p>
+While Lua is running a hook, it disables other calls to hooks.
+Therefore, if a hook calls back Lua to execute a function or a chunk,
+this execution occurs without any calls to hooks.
+
+
+<p>
+Hook functions cannot have continuations,
+that is, they cannot call <a href="#lua_yieldk"><code>lua_yieldk</code></a>,
+<a href="#lua_pcallk"><code>lua_pcallk</code></a>, or <a href="#lua_callk"><code>lua_callk</code></a> with a non-null <code>k</code>.
+
+
+<p>
+Hook functions can yield under the following conditions:
+Only count and line events can yield;
+to yield, a hook function must finish its execution
+calling <a href="#lua_yield"><code>lua_yield</code></a> with <code>nresults</code> equal to zero
+(that is, with no values).
+
+
+
+
+
+<hr><h3><a name="lua_setcstacklimit"><code>lua_setcstacklimit</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>int (lua_setcstacklimit) (lua_State *L, unsigned int limit);</pre>
+
+<p>
+Sets a new limit for the C stack.
+This limit controls how deeply nested calls can go in Lua,
+with the intent of avoiding a stack overflow.
+Returns the old limit in case of success,
+or zero in case of error.
+For more details about this function,
+see <a href="#pdf-debug.setcstacklimit"><code>debug.setcstacklimit</code></a>,
+its equivalent in the standard library.
+
+
+
+
+
+<hr><h3><a name="lua_sethook"><code>lua_sethook</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>void lua_sethook (lua_State *L, lua_Hook f, int mask, int count);</pre>
+
+<p>
+Sets the debugging hook function.
+
+
+<p>
+Argument <code>f</code> is the hook function.
+<code>mask</code> specifies on which events the hook will be called:
+it is formed by a bitwise OR of the constants
+<a name="pdf-LUA_MASKCALL"><code>LUA_MASKCALL</code></a>,
+<a name="pdf-LUA_MASKRET"><code>LUA_MASKRET</code></a>,
+<a name="pdf-LUA_MASKLINE"><code>LUA_MASKLINE</code></a>,
+and <a name="pdf-LUA_MASKCOUNT"><code>LUA_MASKCOUNT</code></a>.
+The <code>count</code> argument is only meaningful when the mask
+includes <code>LUA_MASKCOUNT</code>.
+For each event, the hook is called as explained below:
+
+<ul>
+
+<li><b>The call hook: </b> is called when the interpreter calls a function.
+The hook is called just after Lua enters the new function,
+before the function gets its arguments.
+</li>
+
+<li><b>The return hook: </b> is called when the interpreter returns from a function.
+The hook is called just before Lua leaves the function.
+</li>
+
+<li><b>The line hook: </b> is called when the interpreter is about to
+start the execution of a new line of code,
+or when it jumps back in the code (even to the same line).
+This event only happens while Lua is executing a Lua function.
+</li>
+
+<li><b>The count hook: </b> is called after the interpreter executes every
+<code>count</code> instructions.
+This event only happens while Lua is executing a Lua function.
+</li>
+
+</ul>
+
+<p>
+Hooks are disabled by setting <code>mask</code> to zero.
+
+
+
+
+
+<hr><h3><a name="lua_setlocal"><code>lua_setlocal</code></a></h3><p>
+<span class="apii">[-(0|1), +0, &ndash;]</span>
+<pre>const char *lua_setlocal (lua_State *L, const lua_Debug *ar, int n);</pre>
+
+<p>
+Sets the value of a local variable of a given activation record.
+It assigns the value on the top of the stack
+to the variable and returns its name.
+It also pops the value from the stack.
+
+
+<p>
+Returns <code>NULL</code> (and pops nothing)
+when the index is greater than
+the number of active local variables.
+
+
+<p>
+Parameters <code>ar</code> and <code>n</code> are as in the function <a href="#lua_getlocal"><code>lua_getlocal</code></a>.
+
+
+
+
+
+<hr><h3><a name="lua_setupvalue"><code>lua_setupvalue</code></a></h3><p>
+<span class="apii">[-(0|1), +0, &ndash;]</span>
+<pre>const char *lua_setupvalue (lua_State *L, int funcindex, int n);</pre>
+
+<p>
+Sets the value of a closure's upvalue.
+It assigns the value on the top of the stack
+to the upvalue and returns its name.
+It also pops the value from the stack.
+
+
+<p>
+Returns <code>NULL</code> (and pops nothing)
+when the index <code>n</code> is greater than the number of upvalues.
+
+
+<p>
+Parameters <code>funcindex</code> and <code>n</code> are as in
+the function <a href="#lua_getupvalue"><code>lua_getupvalue</code></a>.
+
+
+
+
+
+<hr><h3><a name="lua_upvalueid"><code>lua_upvalueid</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>void *lua_upvalueid (lua_State *L, int funcindex, int n);</pre>
+
+<p>
+Returns a unique identifier for the upvalue numbered <code>n</code>
+from the closure at index <code>funcindex</code>.
+
+
+<p>
+These unique identifiers allow a program to check whether different
+closures share upvalues.
+Lua closures that share an upvalue
+(that is, that access a same external local variable)
+will return identical ids for those upvalue indices.
+
+
+<p>
+Parameters <code>funcindex</code> and <code>n</code> are as in
+the function <a href="#lua_getupvalue"><code>lua_getupvalue</code></a>,
+but <code>n</code> cannot be greater than the number of upvalues.
+
+
+
+
+
+<hr><h3><a name="lua_upvaluejoin"><code>lua_upvaluejoin</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>void lua_upvaluejoin (lua_State *L, int funcindex1, int n1,
+                                    int funcindex2, int n2);</pre>
+
+<p>
+Make the <code>n1</code>-th upvalue of the Lua closure at index <code>funcindex1</code>
+refer to the <code>n2</code>-th upvalue of the Lua closure at index <code>funcindex2</code>.
+
+
+
+
+
+
+
+<h1>5 &ndash; <a name="5">The Auxiliary Library</a></h1>
+
+
+
+<p>
+
+The <em>auxiliary library</em> provides several convenient functions
+to interface C with Lua.
+While the basic API provides the primitive functions for all
+interactions between C and Lua,
+the auxiliary library provides higher-level functions for some
+common tasks.
+
+
+<p>
+All functions and types from the auxiliary library
+are defined in header file <code>lauxlib.h</code> and
+have a prefix <code>luaL_</code>.
+
+
+<p>
+All functions in the auxiliary library are built on
+top of the basic API,
+and so they provide nothing that cannot be done with that API.
+Nevertheless, the use of the auxiliary library ensures
+more consistency to your code.
+
+
+<p>
+Several functions in the auxiliary library use internally some
+extra stack slots.
+When a function in the auxiliary library uses less than five slots,
+it does not check the stack size;
+it simply assumes that there are enough slots.
+
+
+<p>
+Several functions in the auxiliary library are used to
+check C&nbsp;function arguments.
+Because the error message is formatted for arguments
+(e.g., "<code>bad argument #1</code>"),
+you should not use these functions for other stack values.
+
+
+<p>
+Functions called <code>luaL_check*</code>
+always raise an error if the check is not satisfied.
+
+
+
+
+
+<h2>5.1 &ndash; <a name="5.1">Functions and Types</a></h2>
+
+<p>
+Here we list all functions and types from the auxiliary library
+in alphabetical order.
+
+
+
+<hr><h3><a name="luaL_addchar"><code>luaL_addchar</code></a></h3><p>
+<span class="apii">[-?, +?, <em>m</em>]</span>
+<pre>void luaL_addchar (luaL_Buffer *B, char c);</pre>
+
+<p>
+Adds the byte <code>c</code> to the buffer <code>B</code>
+(see <a href="#luaL_Buffer"><code>luaL_Buffer</code></a>).
+
+
+
+
+
+<hr><h3><a name="luaL_addgsub"><code>luaL_addgsub</code></a></h3><p>
+<span class="apii">[-0, +0, <em>m</em>]</span>
+<pre>const void luaL_addgsub (luaL_Buffer *B, const char *s,
+                         const char *p, const char *r);</pre>
+
+<p>
+Adds a copy of the string <code>s</code> to the buffer <code>B</code> (see <a href="#luaL_Buffer"><code>luaL_Buffer</code></a>),
+replacing any occurrence of the string <code>p</code>
+with the string <code>r</code>.
+
+
+
+
+
+<hr><h3><a name="luaL_addlstring"><code>luaL_addlstring</code></a></h3><p>
+<span class="apii">[-?, +?, <em>m</em>]</span>
+<pre>void luaL_addlstring (luaL_Buffer *B, const char *s, size_t l);</pre>
+
+<p>
+Adds the string pointed to by <code>s</code> with length <code>l</code> to
+the buffer <code>B</code>
+(see <a href="#luaL_Buffer"><code>luaL_Buffer</code></a>).
+The string can contain embedded zeros.
+
+
+
+
+
+<hr><h3><a name="luaL_addsize"><code>luaL_addsize</code></a></h3><p>
+<span class="apii">[-?, +?, &ndash;]</span>
+<pre>void luaL_addsize (luaL_Buffer *B, size_t n);</pre>
+
+<p>
+Adds to the buffer <code>B</code>
+a string of length <code>n</code> previously copied to the
+buffer area (see <a href="#luaL_prepbuffer"><code>luaL_prepbuffer</code></a>).
+
+
+
+
+
+<hr><h3><a name="luaL_addstring"><code>luaL_addstring</code></a></h3><p>
+<span class="apii">[-?, +?, <em>m</em>]</span>
+<pre>void luaL_addstring (luaL_Buffer *B, const char *s);</pre>
+
+<p>
+Adds the zero-terminated string pointed to by <code>s</code>
+to the buffer <code>B</code>
+(see <a href="#luaL_Buffer"><code>luaL_Buffer</code></a>).
+
+
+
+
+
+<hr><h3><a name="luaL_addvalue"><code>luaL_addvalue</code></a></h3><p>
+<span class="apii">[-1, +?, <em>m</em>]</span>
+<pre>void luaL_addvalue (luaL_Buffer *B);</pre>
+
+<p>
+Adds the value on the top of the stack
+to the buffer <code>B</code>
+(see <a href="#luaL_Buffer"><code>luaL_Buffer</code></a>).
+Pops the value.
+
+
+<p>
+This is the only function on string buffers that can (and must)
+be called with an extra element on the stack,
+which is the value to be added to the buffer.
+
+
+
+
+
+<hr><h3><a name="luaL_argcheck"><code>luaL_argcheck</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>void luaL_argcheck (lua_State *L,
+                    int cond,
+                    int arg,
+                    const char *extramsg);</pre>
+
+<p>
+Checks whether <code>cond</code> is true.
+If it is not, raises an error with a standard message (see <a href="#luaL_argerror"><code>luaL_argerror</code></a>).
+
+
+
+
+
+<hr><h3><a name="luaL_argerror"><code>luaL_argerror</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>int luaL_argerror (lua_State *L, int arg, const char *extramsg);</pre>
+
+<p>
+Raises an error reporting a problem with argument <code>arg</code>
+of the C&nbsp;function that called it,
+using a standard message
+that includes <code>extramsg</code> as a comment:
+
+<pre>
+     bad argument #<em>arg</em> to '<em>funcname</em>' (<em>extramsg</em>)
+</pre><p>
+This function never returns.
+
+
+
+
+
+<hr><h3><a name="luaL_argexpected"><code>luaL_argexpected</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>void luaL_argexpected (lua_State *L,
+                       int cond,
+                       int arg,
+                       const char *tname);</pre>
+
+<p>
+Checks whether <code>cond</code> is true.
+If it is not, raises an error about the type of the argument <code>arg</code>
+with a standard message (see <a href="#luaL_typeerror"><code>luaL_typeerror</code></a>).
+
+
+
+
+
+<hr><h3><a name="luaL_Buffer"><code>luaL_Buffer</code></a></h3>
+<pre>typedef struct luaL_Buffer luaL_Buffer;</pre>
+
+<p>
+Type for a <em>string buffer</em>.
+
+
+<p>
+A string buffer allows C&nbsp;code to build Lua strings piecemeal.
+Its pattern of use is as follows:
+
+<ul>
+
+<li>First declare a variable <code>b</code> of type <a href="#luaL_Buffer"><code>luaL_Buffer</code></a>.</li>
+
+<li>Then initialize it with a call <code>luaL_buffinit(L, &amp;b)</code>.</li>
+
+<li>
+Then add string pieces to the buffer calling any of
+the <code>luaL_add*</code> functions.
+</li>
+
+<li>
+Finish by calling <code>luaL_pushresult(&amp;b)</code>.
+This call leaves the final string on the top of the stack.
+</li>
+
+</ul>
+
+<p>
+If you know beforehand the maximum size of the resulting string,
+you can use the buffer like this:
+
+<ul>
+
+<li>First declare a variable <code>b</code> of type <a href="#luaL_Buffer"><code>luaL_Buffer</code></a>.</li>
+
+<li>Then initialize it and preallocate a space of
+size <code>sz</code> with a call <code>luaL_buffinitsize(L, &amp;b, sz)</code>.</li>
+
+<li>Then produce the string into that space.</li>
+
+<li>
+Finish by calling <code>luaL_pushresultsize(&amp;b, sz)</code>,
+where <code>sz</code> is the total size of the resulting string
+copied into that space (which may be less than or
+equal to the preallocated size).
+</li>
+
+</ul>
+
+<p>
+During its normal operation,
+a string buffer uses a variable number of stack slots.
+So, while using a buffer, you cannot assume that you know where
+the top of the stack is.
+You can use the stack between successive calls to buffer operations
+as long as that use is balanced;
+that is,
+when you call a buffer operation,
+the stack is at the same level
+it was immediately after the previous buffer operation.
+(The only exception to this rule is <a href="#luaL_addvalue"><code>luaL_addvalue</code></a>.)
+After calling <a href="#luaL_pushresult"><code>luaL_pushresult</code></a>,
+the stack is back to its level when the buffer was initialized,
+plus the final string on its top.
+
+
+
+
+
+<hr><h3><a name="luaL_buffaddr"><code>luaL_buffaddr</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>char *luaL_buffaddr (luaL_Buffer *B);</pre>
+
+<p>
+Returns the address of the current content of buffer <code>B</code>
+(see <a href="#luaL_Buffer"><code>luaL_Buffer</code></a>).
+Note that any addition to the buffer may invalidate this address.
+
+
+
+
+
+<hr><h3><a name="luaL_buffinit"><code>luaL_buffinit</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>void luaL_buffinit (lua_State *L, luaL_Buffer *B);</pre>
+
+<p>
+Initializes a buffer <code>B</code>
+(see <a href="#luaL_Buffer"><code>luaL_Buffer</code></a>).
+This function does not allocate any space;
+the buffer must be declared as a variable.
+
+
+
+
+
+<hr><h3><a name="luaL_bufflen"><code>luaL_bufflen</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>size_t luaL_bufflen (luaL_Buffer *B);</pre>
+
+<p>
+Returns the length of the current content of buffer <code>B</code>
+(see <a href="#luaL_Buffer"><code>luaL_Buffer</code></a>).
+
+
+
+
+
+<hr><h3><a name="luaL_buffinitsize"><code>luaL_buffinitsize</code></a></h3><p>
+<span class="apii">[-?, +?, <em>m</em>]</span>
+<pre>char *luaL_buffinitsize (lua_State *L, luaL_Buffer *B, size_t sz);</pre>
+
+<p>
+Equivalent to the sequence
+<a href="#luaL_buffinit"><code>luaL_buffinit</code></a>, <a href="#luaL_prepbuffsize"><code>luaL_prepbuffsize</code></a>.
+
+
+
+
+
+<hr><h3><a name="luaL_buffsub"><code>luaL_buffsub</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>void luaL_buffsub (luaL_Buffer *B, int n);</pre>
+
+<p>
+Removes <code>n</code> bytes from the the buffer <code>B</code>
+(see <a href="#luaL_Buffer"><code>luaL_Buffer</code></a>).
+The buffer must have at least that many bytes.
+
+
+
+
+
+<hr><h3><a name="luaL_callmeta"><code>luaL_callmeta</code></a></h3><p>
+<span class="apii">[-0, +(0|1), <em>e</em>]</span>
+<pre>int luaL_callmeta (lua_State *L, int obj, const char *e);</pre>
+
+<p>
+Calls a metamethod.
+
+
+<p>
+If the object at index <code>obj</code> has a metatable and this
+metatable has a field <code>e</code>,
+this function calls this field passing the object as its only argument.
+In this case this function returns true and pushes onto the
+stack the value returned by the call.
+If there is no metatable or no metamethod,
+this function returns false without pushing any value on the stack.
+
+
+
+
+
+<hr><h3><a name="luaL_checkany"><code>luaL_checkany</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>void luaL_checkany (lua_State *L, int arg);</pre>
+
+<p>
+Checks whether the function has an argument
+of any type (including <b>nil</b>) at position <code>arg</code>.
+
+
+
+
+
+<hr><h3><a name="luaL_checkinteger"><code>luaL_checkinteger</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>lua_Integer luaL_checkinteger (lua_State *L, int arg);</pre>
+
+<p>
+Checks whether the function argument <code>arg</code> is an integer
+(or can be converted to an integer)
+and returns this integer.
+
+
+
+
+
+<hr><h3><a name="luaL_checklstring"><code>luaL_checklstring</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>const char *luaL_checklstring (lua_State *L, int arg, size_t *l);</pre>
+
+<p>
+Checks whether the function argument <code>arg</code> is a string
+and returns this string;
+if <code>l</code> is not <code>NULL</code> fills its referent
+with the string's length.
+
+
+<p>
+This function uses <a href="#lua_tolstring"><code>lua_tolstring</code></a> to get its result,
+so all conversions and caveats of that function apply here.
+
+
+
+
+
+<hr><h3><a name="luaL_checknumber"><code>luaL_checknumber</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>lua_Number luaL_checknumber (lua_State *L, int arg);</pre>
+
+<p>
+Checks whether the function argument <code>arg</code> is a number
+and returns this number converted to a <code>lua_Number</code>.
+
+
+
+
+
+<hr><h3><a name="luaL_checkoption"><code>luaL_checkoption</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>int luaL_checkoption (lua_State *L,
+                      int arg,
+                      const char *def,
+                      const char *const lst[]);</pre>
+
+<p>
+Checks whether the function argument <code>arg</code> is a string and
+searches for this string in the array <code>lst</code>
+(which must be NULL-terminated).
+Returns the index in the array where the string was found.
+Raises an error if the argument is not a string or
+if the string cannot be found.
+
+
+<p>
+If <code>def</code> is not <code>NULL</code>,
+the function uses <code>def</code> as a default value when
+there is no argument <code>arg</code> or when this argument is <b>nil</b>.
+
+
+<p>
+This is a useful function for mapping strings to C&nbsp;enums.
+(The usual convention in Lua libraries is
+to use strings instead of numbers to select options.)
+
+
+
+
+
+<hr><h3><a name="luaL_checkstack"><code>luaL_checkstack</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>void luaL_checkstack (lua_State *L, int sz, const char *msg);</pre>
+
+<p>
+Grows the stack size to <code>top + sz</code> elements,
+raising an error if the stack cannot grow to that size.
+<code>msg</code> is an additional text to go into the error message
+(or <code>NULL</code> for no additional text).
+
+
+
+
+
+<hr><h3><a name="luaL_checkstring"><code>luaL_checkstring</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>const char *luaL_checkstring (lua_State *L, int arg);</pre>
+
+<p>
+Checks whether the function argument <code>arg</code> is a string
+and returns this string.
+
+
+<p>
+This function uses <a href="#lua_tolstring"><code>lua_tolstring</code></a> to get its result,
+so all conversions and caveats of that function apply here.
+
+
+
+
+
+<hr><h3><a name="luaL_checktype"><code>luaL_checktype</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>void luaL_checktype (lua_State *L, int arg, int t);</pre>
+
+<p>
+Checks whether the function argument <code>arg</code> has type <code>t</code>.
+See <a href="#lua_type"><code>lua_type</code></a> for the encoding of types for <code>t</code>.
+
+
+
+
+
+<hr><h3><a name="luaL_checkudata"><code>luaL_checkudata</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>void *luaL_checkudata (lua_State *L, int arg, const char *tname);</pre>
+
+<p>
+Checks whether the function argument <code>arg</code> is a userdata
+of the type <code>tname</code> (see <a href="#luaL_newmetatable"><code>luaL_newmetatable</code></a>) and
+returns the userdata's memory-block address (see <a href="#lua_touserdata"><code>lua_touserdata</code></a>).
+
+
+
+
+
+<hr><h3><a name="luaL_checkversion"><code>luaL_checkversion</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>void luaL_checkversion (lua_State *L);</pre>
+
+<p>
+Checks whether the code making the call and the Lua library being called
+are using the same version of Lua and the same numeric types.
+
+
+
+
+
+<hr><h3><a name="luaL_dofile"><code>luaL_dofile</code></a></h3><p>
+<span class="apii">[-0, +?, <em>m</em>]</span>
+<pre>int luaL_dofile (lua_State *L, const char *filename);</pre>
+
+<p>
+Loads and runs the given file.
+It is defined as the following macro:
+
+<pre>
+     (luaL_loadfile(L, filename) || lua_pcall(L, 0, LUA_MULTRET, 0))
+</pre><p>
+It returns <a href="#pdf-LUA_OK"><code>LUA_OK</code></a> if there are no errors,
+or an error code in case of errors (see <a href="#4.4.1">&sect;4.4.1</a>).
+
+
+
+
+
+<hr><h3><a name="luaL_dostring"><code>luaL_dostring</code></a></h3><p>
+<span class="apii">[-0, +?, &ndash;]</span>
+<pre>int luaL_dostring (lua_State *L, const char *str);</pre>
+
+<p>
+Loads and runs the given string.
+It is defined as the following macro:
+
+<pre>
+     (luaL_loadstring(L, str) || lua_pcall(L, 0, LUA_MULTRET, 0))
+</pre><p>
+It returns <a href="#pdf-LUA_OK"><code>LUA_OK</code></a> if there are no errors,
+or an error code in case of errors (see <a href="#4.4.1">&sect;4.4.1</a>).
+
+
+
+
+
+<hr><h3><a name="luaL_error"><code>luaL_error</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>int luaL_error (lua_State *L, const char *fmt, ...);</pre>
+
+<p>
+Raises an error.
+The error message format is given by <code>fmt</code>
+plus any extra arguments,
+following the same rules of <a href="#lua_pushfstring"><code>lua_pushfstring</code></a>.
+It also adds at the beginning of the message the file name and
+the line number where the error occurred,
+if this information is available.
+
+
+<p>
+This function never returns,
+but it is an idiom to use it in C&nbsp;functions
+as <code>return luaL_error(<em>args</em>)</code>.
+
+
+
+
+
+<hr><h3><a name="luaL_execresult"><code>luaL_execresult</code></a></h3><p>
+<span class="apii">[-0, +3, <em>m</em>]</span>
+<pre>int luaL_execresult (lua_State *L, int stat);</pre>
+
+<p>
+This function produces the return values for
+process-related functions in the standard library
+(<a href="#pdf-os.execute"><code>os.execute</code></a> and <a href="#pdf-io.close"><code>io.close</code></a>).
+
+
+
+
+
+<hr><h3><a name="luaL_fileresult"><code>luaL_fileresult</code></a></h3><p>
+<span class="apii">[-0, +(1|3), <em>m</em>]</span>
+<pre>int luaL_fileresult (lua_State *L, int stat, const char *fname);</pre>
+
+<p>
+This function produces the return values for
+file-related functions in the standard library
+(<a href="#pdf-io.open"><code>io.open</code></a>, <a href="#pdf-os.rename"><code>os.rename</code></a>, <a href="#pdf-file:seek"><code>file:seek</code></a>, etc.).
+
+
+
+
+
+<hr><h3><a name="luaL_getmetafield"><code>luaL_getmetafield</code></a></h3><p>
+<span class="apii">[-0, +(0|1), <em>m</em>]</span>
+<pre>int luaL_getmetafield (lua_State *L, int obj, const char *e);</pre>
+
+<p>
+Pushes onto the stack the field <code>e</code> from the metatable
+of the object at index <code>obj</code> and returns the type of the pushed value.
+If the object does not have a metatable,
+or if the metatable does not have this field,
+pushes nothing and returns <code>LUA_TNIL</code>.
+
+
+
+
+
+<hr><h3><a name="luaL_getmetatable"><code>luaL_getmetatable</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>int luaL_getmetatable (lua_State *L, const char *tname);</pre>
+
+<p>
+Pushes onto the stack the metatable associated with the name <code>tname</code>
+in the registry (see <a href="#luaL_newmetatable"><code>luaL_newmetatable</code></a>),
+or <b>nil</b> if there is no metatable associated with that name.
+Returns the type of the pushed value.
+
+
+
+
+
+<hr><h3><a name="luaL_getsubtable"><code>luaL_getsubtable</code></a></h3><p>
+<span class="apii">[-0, +1, <em>e</em>]</span>
+<pre>int luaL_getsubtable (lua_State *L, int idx, const char *fname);</pre>
+
+<p>
+Ensures that the value <code>t[fname]</code>,
+where <code>t</code> is the value at index <code>idx</code>,
+is a table,
+and pushes that table onto the stack.
+Returns true if it finds a previous table there
+and false if it creates a new table.
+
+
+
+
+
+<hr><h3><a name="luaL_gsub"><code>luaL_gsub</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>const char *luaL_gsub (lua_State *L,
+                       const char *s,
+                       const char *p,
+                       const char *r);</pre>
+
+<p>
+Creates a copy of string <code>s</code>,
+replacing any occurrence of the string <code>p</code>
+with the string <code>r</code>.
+Pushes the resulting string on the stack and returns it.
+
+
+
+
+
+<hr><h3><a name="luaL_len"><code>luaL_len</code></a></h3><p>
+<span class="apii">[-0, +0, <em>e</em>]</span>
+<pre>lua_Integer luaL_len (lua_State *L, int index);</pre>
+
+<p>
+Returns the "length" of the value at the given index
+as a number;
+it is equivalent to the '<code>#</code>' operator in Lua (see <a href="#3.4.7">&sect;3.4.7</a>).
+Raises an error if the result of the operation is not an integer.
+(This case can only happen through metamethods.)
+
+
+
+
+
+<hr><h3><a name="luaL_loadbuffer"><code>luaL_loadbuffer</code></a></h3><p>
+<span class="apii">[-0, +1, &ndash;]</span>
+<pre>int luaL_loadbuffer (lua_State *L,
+                     const char *buff,
+                     size_t sz,
+                     const char *name);</pre>
+
+<p>
+Equivalent to <a href="#luaL_loadbufferx"><code>luaL_loadbufferx</code></a> with <code>mode</code> equal to <code>NULL</code>.
+
+
+
+
+
+<hr><h3><a name="luaL_loadbufferx"><code>luaL_loadbufferx</code></a></h3><p>
+<span class="apii">[-0, +1, &ndash;]</span>
+<pre>int luaL_loadbufferx (lua_State *L,
+                      const char *buff,
+                      size_t sz,
+                      const char *name,
+                      const char *mode);</pre>
+
+<p>
+Loads a buffer as a Lua chunk.
+This function uses <a href="#lua_load"><code>lua_load</code></a> to load the chunk in the
+buffer pointed to by <code>buff</code> with size <code>sz</code>.
+
+
+<p>
+This function returns the same results as <a href="#lua_load"><code>lua_load</code></a>.
+<code>name</code> is the chunk name,
+used for debug information and error messages.
+The string <code>mode</code> works as in the function <a href="#lua_load"><code>lua_load</code></a>.
+
+
+
+
+
+<hr><h3><a name="luaL_loadfile"><code>luaL_loadfile</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>int luaL_loadfile (lua_State *L, const char *filename);</pre>
+
+<p>
+Equivalent to <a href="#luaL_loadfilex"><code>luaL_loadfilex</code></a> with <code>mode</code> equal to <code>NULL</code>.
+
+
+
+
+
+<hr><h3><a name="luaL_loadfilex"><code>luaL_loadfilex</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>int luaL_loadfilex (lua_State *L, const char *filename,
+                                            const char *mode);</pre>
+
+<p>
+Loads a file as a Lua chunk.
+This function uses <a href="#lua_load"><code>lua_load</code></a> to load the chunk in the file
+named <code>filename</code>.
+If <code>filename</code> is <code>NULL</code>,
+then it loads from the standard input.
+The first line in the file is ignored if it starts with a <code>#</code>.
+
+
+<p>
+The string <code>mode</code> works as in the function <a href="#lua_load"><code>lua_load</code></a>.
+
+
+<p>
+This function returns the same results as <a href="#lua_load"><code>lua_load</code></a>
+or <a href="#pdf-LUA_ERRFILE"><code>LUA_ERRFILE</code></a> for file-related errors.
+
+
+<p>
+As <a href="#lua_load"><code>lua_load</code></a>, this function only loads the chunk;
+it does not run it.
+
+
+
+
+
+<hr><h3><a name="luaL_loadstring"><code>luaL_loadstring</code></a></h3><p>
+<span class="apii">[-0, +1, &ndash;]</span>
+<pre>int luaL_loadstring (lua_State *L, const char *s);</pre>
+
+<p>
+Loads a string as a Lua chunk.
+This function uses <a href="#lua_load"><code>lua_load</code></a> to load the chunk in
+the zero-terminated string <code>s</code>.
+
+
+<p>
+This function returns the same results as <a href="#lua_load"><code>lua_load</code></a>.
+
+
+<p>
+Also as <a href="#lua_load"><code>lua_load</code></a>, this function only loads the chunk;
+it does not run it.
+
+
+
+
+
+<hr><h3><a name="luaL_newlib"><code>luaL_newlib</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>void luaL_newlib (lua_State *L, const luaL_Reg l[]);</pre>
+
+<p>
+Creates a new table and registers there
+the functions in the list <code>l</code>.
+
+
+<p>
+It is implemented as the following macro:
+
+<pre>
+     (luaL_newlibtable(L,l), luaL_setfuncs(L,l,0))
+</pre><p>
+The array <code>l</code> must be the actual array,
+not a pointer to it.
+
+
+
+
+
+<hr><h3><a name="luaL_newlibtable"><code>luaL_newlibtable</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>void luaL_newlibtable (lua_State *L, const luaL_Reg l[]);</pre>
+
+<p>
+Creates a new table with a size optimized
+to store all entries in the array <code>l</code>
+(but does not actually store them).
+It is intended to be used in conjunction with <a href="#luaL_setfuncs"><code>luaL_setfuncs</code></a>
+(see <a href="#luaL_newlib"><code>luaL_newlib</code></a>).
+
+
+<p>
+It is implemented as a macro.
+The array <code>l</code> must be the actual array,
+not a pointer to it.
+
+
+
+
+
+<hr><h3><a name="luaL_newmetatable"><code>luaL_newmetatable</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>int luaL_newmetatable (lua_State *L, const char *tname);</pre>
+
+<p>
+If the registry already has the key <code>tname</code>,
+returns 0.
+Otherwise,
+creates a new table to be used as a metatable for userdata,
+adds to this new table the pair <code>__name = tname</code>,
+adds to the registry the pair <code>[tname] = new table</code>,
+and returns 1.
+
+
+<p>
+In both cases,
+the function pushes onto the stack the final value associated
+with <code>tname</code> in the registry.
+
+
+
+
+
+<hr><h3><a name="luaL_newstate"><code>luaL_newstate</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>lua_State *luaL_newstate (void);</pre>
+
+<p>
+Creates a new Lua state.
+It calls <a href="#lua_newstate"><code>lua_newstate</code></a> with an
+allocator based on the standard&nbsp;C allocation functions
+and then sets a warning function and a panic function (see <a href="#4.4">&sect;4.4</a>)
+that print messages to the standard error output.
+
+
+<p>
+Returns the new state,
+or <code>NULL</code> if there is a memory allocation error.
+
+
+
+
+
+<hr><h3><a name="luaL_openlibs"><code>luaL_openlibs</code></a></h3><p>
+<span class="apii">[-0, +0, <em>e</em>]</span>
+<pre>void luaL_openlibs (lua_State *L);</pre>
+
+<p>
+Opens all standard Lua libraries into the given state.
+
+
+
+
+
+<hr><h3><a name="luaL_opt"><code>luaL_opt</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>T luaL_opt (L, func, arg, dflt);</pre>
+
+<p>
+This macro is defined as follows:
+
+<pre>
+     (lua_isnoneornil(L,(arg)) ? (dflt) : func(L,(arg)))
+</pre><p>
+In words, if the argument <code>arg</code> is nil or absent,
+the macro results in the default <code>dflt</code>.
+Otherwise, it results in the result of calling <code>func</code>
+with the state <code>L</code> and the argument index <code>arg</code> as
+arguments.
+Note that it evaluates the expression <code>dflt</code> only if needed.
+
+
+
+
+
+<hr><h3><a name="luaL_optinteger"><code>luaL_optinteger</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>lua_Integer luaL_optinteger (lua_State *L,
+                             int arg,
+                             lua_Integer d);</pre>
+
+<p>
+If the function argument <code>arg</code> is an integer
+(or it is convertible to an integer),
+returns this integer.
+If this argument is absent or is <b>nil</b>,
+returns <code>d</code>.
+Otherwise, raises an error.
+
+
+
+
+
+<hr><h3><a name="luaL_optlstring"><code>luaL_optlstring</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>const char *luaL_optlstring (lua_State *L,
+                             int arg,
+                             const char *d,
+                             size_t *l);</pre>
+
+<p>
+If the function argument <code>arg</code> is a string,
+returns this string.
+If this argument is absent or is <b>nil</b>,
+returns <code>d</code>.
+Otherwise, raises an error.
+
+
+<p>
+If <code>l</code> is not <code>NULL</code>,
+fills its referent with the result's length.
+If the result is <code>NULL</code>
+(only possible when returning <code>d</code> and <code>d == NULL</code>),
+its length is considered zero.
+
+
+<p>
+This function uses <a href="#lua_tolstring"><code>lua_tolstring</code></a> to get its result,
+so all conversions and caveats of that function apply here.
+
+
+
+
+
+<hr><h3><a name="luaL_optnumber"><code>luaL_optnumber</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>lua_Number luaL_optnumber (lua_State *L, int arg, lua_Number d);</pre>
+
+<p>
+If the function argument <code>arg</code> is a number,
+returns this number as a <code>lua_Number</code>.
+If this argument is absent or is <b>nil</b>,
+returns <code>d</code>.
+Otherwise, raises an error.
+
+
+
+
+
+<hr><h3><a name="luaL_optstring"><code>luaL_optstring</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>const char *luaL_optstring (lua_State *L,
+                            int arg,
+                            const char *d);</pre>
+
+<p>
+If the function argument <code>arg</code> is a string,
+returns this string.
+If this argument is absent or is <b>nil</b>,
+returns <code>d</code>.
+Otherwise, raises an error.
+
+
+
+
+
+<hr><h3><a name="luaL_prepbuffer"><code>luaL_prepbuffer</code></a></h3><p>
+<span class="apii">[-?, +?, <em>m</em>]</span>
+<pre>char *luaL_prepbuffer (luaL_Buffer *B);</pre>
+
+<p>
+Equivalent to <a href="#luaL_prepbuffsize"><code>luaL_prepbuffsize</code></a>
+with the predefined size <a name="pdf-LUAL_BUFFERSIZE"><code>LUAL_BUFFERSIZE</code></a>.
+
+
+
+
+
+<hr><h3><a name="luaL_prepbuffsize"><code>luaL_prepbuffsize</code></a></h3><p>
+<span class="apii">[-?, +?, <em>m</em>]</span>
+<pre>char *luaL_prepbuffsize (luaL_Buffer *B, size_t sz);</pre>
+
+<p>
+Returns an address to a space of size <code>sz</code>
+where you can copy a string to be added to buffer <code>B</code>
+(see <a href="#luaL_Buffer"><code>luaL_Buffer</code></a>).
+After copying the string into this space you must call
+<a href="#luaL_addsize"><code>luaL_addsize</code></a> with the size of the string to actually add
+it to the buffer.
+
+
+
+
+
+<hr><h3><a name="luaL_pushfail"><code>luaL_pushfail</code></a></h3><p>
+<span class="apii">[-0, +1, &ndash;]</span>
+<pre>void luaL_pushfail (lua_State *L);</pre>
+
+<p>
+Pushes the <b>fail</b> value onto the stack (see <a href="#6">&sect;6</a>).
+
+
+
+
+
+<hr><h3><a name="luaL_pushresult"><code>luaL_pushresult</code></a></h3><p>
+<span class="apii">[-?, +1, <em>m</em>]</span>
+<pre>void luaL_pushresult (luaL_Buffer *B);</pre>
+
+<p>
+Finishes the use of buffer <code>B</code> leaving the final string on
+the top of the stack.
+
+
+
+
+
+<hr><h3><a name="luaL_pushresultsize"><code>luaL_pushresultsize</code></a></h3><p>
+<span class="apii">[-?, +1, <em>m</em>]</span>
+<pre>void luaL_pushresultsize (luaL_Buffer *B, size_t sz);</pre>
+
+<p>
+Equivalent to the sequence <a href="#luaL_addsize"><code>luaL_addsize</code></a>, <a href="#luaL_pushresult"><code>luaL_pushresult</code></a>.
+
+
+
+
+
+<hr><h3><a name="luaL_ref"><code>luaL_ref</code></a></h3><p>
+<span class="apii">[-1, +0, <em>m</em>]</span>
+<pre>int luaL_ref (lua_State *L, int t);</pre>
+
+<p>
+Creates and returns a <em>reference</em>,
+in the table at index <code>t</code>,
+for the object on the top of the stack (and pops the object).
+
+
+<p>
+A reference is a unique integer key.
+As long as you do not manually add integer keys into the table <code>t</code>,
+<a href="#luaL_ref"><code>luaL_ref</code></a> ensures the uniqueness of the key it returns.
+You can retrieve an object referred by the reference <code>r</code>
+by calling <code>lua_rawgeti(L, t, r)</code>.
+The function <a href="#luaL_unref"><code>luaL_unref</code></a> frees a reference.
+
+
+<p>
+If the object on the top of the stack is <b>nil</b>,
+<a href="#luaL_ref"><code>luaL_ref</code></a> returns the constant <a name="pdf-LUA_REFNIL"><code>LUA_REFNIL</code></a>.
+The constant <a name="pdf-LUA_NOREF"><code>LUA_NOREF</code></a> is guaranteed to be different
+from any reference returned by <a href="#luaL_ref"><code>luaL_ref</code></a>.
+
+
+
+
+
+<hr><h3><a name="luaL_Reg"><code>luaL_Reg</code></a></h3>
+<pre>typedef struct luaL_Reg {
+  const char *name;
+  lua_CFunction func;
+} luaL_Reg;</pre>
+
+<p>
+Type for arrays of functions to be registered by
+<a href="#luaL_setfuncs"><code>luaL_setfuncs</code></a>.
+<code>name</code> is the function name and <code>func</code> is a pointer to
+the function.
+Any array of <a href="#luaL_Reg"><code>luaL_Reg</code></a> must end with a sentinel entry
+in which both <code>name</code> and <code>func</code> are <code>NULL</code>.
+
+
+
+
+
+<hr><h3><a name="luaL_requiref"><code>luaL_requiref</code></a></h3><p>
+<span class="apii">[-0, +1, <em>e</em>]</span>
+<pre>void luaL_requiref (lua_State *L, const char *modname,
+                    lua_CFunction openf, int glb);</pre>
+
+<p>
+If <code>package.loaded[modname]</code> is not true,
+calls the function <code>openf</code> with the string <code>modname</code> as an argument
+and sets the call result to <code>package.loaded[modname]</code>,
+as if that function has been called through <a href="#pdf-require"><code>require</code></a>.
+
+
+<p>
+If <code>glb</code> is true,
+also stores the module into the global <code>modname</code>.
+
+
+<p>
+Leaves a copy of the module on the stack.
+
+
+
+
+
+<hr><h3><a name="luaL_setfuncs"><code>luaL_setfuncs</code></a></h3><p>
+<span class="apii">[-nup, +0, <em>m</em>]</span>
+<pre>void luaL_setfuncs (lua_State *L, const luaL_Reg *l, int nup);</pre>
+
+<p>
+Registers all functions in the array <code>l</code>
+(see <a href="#luaL_Reg"><code>luaL_Reg</code></a>) into the table on the top of the stack
+(below optional upvalues, see next).
+
+
+<p>
+When <code>nup</code> is not zero,
+all functions are created with <code>nup</code> upvalues,
+initialized with copies of the <code>nup</code> values
+previously pushed on the stack
+on top of the library table.
+These values are popped from the stack after the registration.
+
+
+
+
+
+<hr><h3><a name="luaL_setmetatable"><code>luaL_setmetatable</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>void luaL_setmetatable (lua_State *L, const char *tname);</pre>
+
+<p>
+Sets the metatable of the object on the top of the stack
+as the metatable associated with name <code>tname</code>
+in the registry (see <a href="#luaL_newmetatable"><code>luaL_newmetatable</code></a>).
+
+
+
+
+
+<hr><h3><a name="luaL_Stream"><code>luaL_Stream</code></a></h3>
+<pre>typedef struct luaL_Stream {
+  FILE *f;
+  lua_CFunction closef;
+} luaL_Stream;</pre>
+
+<p>
+The standard representation for file handles
+used by the standard I/O library.
+
+
+<p>
+A file handle is implemented as a full userdata,
+with a metatable called <code>LUA_FILEHANDLE</code>
+(where <code>LUA_FILEHANDLE</code> is a macro with the actual metatable's name).
+The metatable is created by the I/O library
+(see <a href="#luaL_newmetatable"><code>luaL_newmetatable</code></a>).
+
+
+<p>
+This userdata must start with the structure <code>luaL_Stream</code>;
+it can contain other data after this initial structure.
+The field <code>f</code> points to the corresponding C stream
+(or it can be <code>NULL</code> to indicate an incompletely created handle).
+The field <code>closef</code> points to a Lua function
+that will be called to close the stream
+when the handle is closed or collected;
+this function receives the file handle as its sole argument and
+must return either a true value, in case of success,
+or a false value plus an error message, in case of error.
+Once Lua calls this field,
+it changes the field value to <code>NULL</code>
+to signal that the handle is closed.
+
+
+
+
+
+<hr><h3><a name="luaL_testudata"><code>luaL_testudata</code></a></h3><p>
+<span class="apii">[-0, +0, <em>m</em>]</span>
+<pre>void *luaL_testudata (lua_State *L, int arg, const char *tname);</pre>
+
+<p>
+This function works like <a href="#luaL_checkudata"><code>luaL_checkudata</code></a>,
+except that, when the test fails,
+it returns <code>NULL</code> instead of raising an error.
+
+
+
+
+
+<hr><h3><a name="luaL_tolstring"><code>luaL_tolstring</code></a></h3><p>
+<span class="apii">[-0, +1, <em>e</em>]</span>
+<pre>const char *luaL_tolstring (lua_State *L, int idx, size_t *len);</pre>
+
+<p>
+Converts any Lua value at the given index to a C&nbsp;string
+in a reasonable format.
+The resulting string is pushed onto the stack and also
+returned by the function.
+If <code>len</code> is not <code>NULL</code>,
+the function also sets <code>*len</code> with the string length.
+
+
+<p>
+If the value has a metatable with a <code>__tostring</code> field,
+then <code>luaL_tolstring</code> calls the corresponding metamethod
+with the value as argument,
+and uses the result of the call as its result.
+
+
+
+
+
+<hr><h3><a name="luaL_traceback"><code>luaL_traceback</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>void luaL_traceback (lua_State *L, lua_State *L1, const char *msg,
+                     int level);</pre>
+
+<p>
+Creates and pushes a traceback of the stack <code>L1</code>.
+If <code>msg</code> is not <code>NULL</code>, it is appended
+at the beginning of the traceback.
+The <code>level</code> parameter tells at which level
+to start the traceback.
+
+
+
+
+
+<hr><h3><a name="luaL_typeerror"><code>luaL_typeerror</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>const char *luaL_typeerror (lua_State *L,
+                                      int arg,
+                                      const char *tname);</pre>
+
+<p>
+Raises a type error for the argument <code>arg</code>
+of the C&nbsp;function that called it,
+using a standard message;
+<code>tname</code> is a "name" for the expected type.
+This function never returns.
+
+
+
+
+
+<hr><h3><a name="luaL_typename"><code>luaL_typename</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>const char *luaL_typename (lua_State *L, int index);</pre>
+
+<p>
+Returns the name of the type of the value at the given index.
+
+
+
+
+
+<hr><h3><a name="luaL_unref"><code>luaL_unref</code></a></h3><p>
+<span class="apii">[-0, +0, &ndash;]</span>
+<pre>void luaL_unref (lua_State *L, int t, int ref);</pre>
+
+<p>
+Releases the reference <code>ref</code> from the table at index <code>t</code>
+(see <a href="#luaL_ref"><code>luaL_ref</code></a>).
+The entry is removed from the table,
+so that the referred object can be collected.
+The reference <code>ref</code> is also freed to be used again.
+
+
+<p>
+If <code>ref</code> is <a href="#pdf-LUA_NOREF"><code>LUA_NOREF</code></a> or <a href="#pdf-LUA_REFNIL"><code>LUA_REFNIL</code></a>,
+<a href="#luaL_unref"><code>luaL_unref</code></a> does nothing.
+
+
+
+
+
+<hr><h3><a name="luaL_where"><code>luaL_where</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>void luaL_where (lua_State *L, int lvl);</pre>
+
+<p>
+Pushes onto the stack a string identifying the current position
+of the control at level <code>lvl</code> in the call stack.
+Typically this string has the following format:
+
+<pre>
+     <em>chunkname</em>:<em>currentline</em>:
+</pre><p>
+Level&nbsp;0 is the running function,
+level&nbsp;1 is the function that called the running function,
+etc.
+
+
+<p>
+This function is used to build a prefix for error messages.
+
+
+
+
+
+
+
+<h1>6 &ndash; <a name="6">The Standard Libraries</a></h1>
+
+
+
+<p>
+The standard Lua libraries provide useful functions
+that are implemented in&nbsp;C through the C&nbsp;API.
+Some of these functions provide essential services to the language
+(e.g., <a href="#pdf-type"><code>type</code></a> and <a href="#pdf-getmetatable"><code>getmetatable</code></a>);
+others provide access to outside services (e.g., I/O);
+and others could be implemented in Lua itself,
+but that for different reasons
+deserve an implementation in C (e.g., <a href="#pdf-table.sort"><code>table.sort</code></a>).
+
+
+<p>
+All libraries are implemented through the official C&nbsp;API
+and are provided as separate C&nbsp;modules.
+Unless otherwise noted,
+these library functions do not adjust its number of arguments
+to its expected parameters.
+For instance, a function documented as <code>foo(arg)</code>
+should not be called without an argument.
+
+
+<p>
+The notation <b>fail</b> means a false value representing
+some kind of failure.
+(Currently, <b>fail</b> is equal to <b>nil</b>,
+but that may change in future versions.
+The recommendation is to always test the success of these functions
+with <code>(not status)</code>, instead of <code>(status == nil)</code>.)
+
+
+<p>
+Currently, Lua has the following standard libraries:
+
+<ul>
+
+<li>basic library (<a href="#6.1">&sect;6.1</a>);</li>
+
+<li>coroutine library (<a href="#6.2">&sect;6.2</a>);</li>
+
+<li>package library (<a href="#6.3">&sect;6.3</a>);</li>
+
+<li>string manipulation (<a href="#6.4">&sect;6.4</a>);</li>
+
+<li>basic UTF-8 support (<a href="#6.5">&sect;6.5</a>);</li>
+
+<li>table manipulation (<a href="#6.6">&sect;6.6</a>);</li>
+
+<li>mathematical functions (<a href="#6.7">&sect;6.7</a>) (sin, log, etc.);</li>
+
+<li>input and output (<a href="#6.8">&sect;6.8</a>);</li>
+
+<li>operating system facilities (<a href="#6.9">&sect;6.9</a>);</li>
+
+<li>debug facilities (<a href="#6.10">&sect;6.10</a>).</li>
+
+</ul><p>
+Except for the basic and the package libraries,
+each library provides all its functions as fields of a global table
+or as methods of its objects.
+
+
+<p>
+To have access to these libraries,
+the C&nbsp;host program should call the <a href="#luaL_openlibs"><code>luaL_openlibs</code></a> function,
+which opens all standard libraries.
+Alternatively,
+the host program can open them individually by using
+<a href="#luaL_requiref"><code>luaL_requiref</code></a> to call
+<a name="pdf-luaopen_base"><code>luaopen_base</code></a> (for the basic library),
+<a name="pdf-luaopen_package"><code>luaopen_package</code></a> (for the package library),
+<a name="pdf-luaopen_coroutine"><code>luaopen_coroutine</code></a> (for the coroutine library),
+<a name="pdf-luaopen_string"><code>luaopen_string</code></a> (for the string library),
+<a name="pdf-luaopen_utf8"><code>luaopen_utf8</code></a> (for the UTF-8 library),
+<a name="pdf-luaopen_table"><code>luaopen_table</code></a> (for the table library),
+<a name="pdf-luaopen_math"><code>luaopen_math</code></a> (for the mathematical library),
+<a name="pdf-luaopen_io"><code>luaopen_io</code></a> (for the I/O library),
+<a name="pdf-luaopen_os"><code>luaopen_os</code></a> (for the operating system library),
+and <a name="pdf-luaopen_debug"><code>luaopen_debug</code></a> (for the debug library).
+These functions are declared in <a name="pdf-lualib.h"><code>lualib.h</code></a>.
+
+
+
+
+
+<h2>6.1 &ndash; <a name="6.1">Basic Functions</a></h2>
+
+<p>
+The basic library provides core functions to Lua.
+If you do not include this library in your application,
+you should check carefully whether you need to provide
+implementations for some of its facilities.
+
+
+<p>
+<hr><h3><a name="pdf-assert"><code>assert (v [, message])</code></a></h3>
+
+
+<p>
+Raises an error if
+the value of its argument <code>v</code> is false (i.e., <b>nil</b> or <b>false</b>);
+otherwise, returns all its arguments.
+In case of error,
+<code>message</code> is the error object;
+when absent, it defaults to "<code>assertion failed!</code>"
+
+
+
+
+<p>
+<hr><h3><a name="pdf-collectgarbage"><code>collectgarbage ([opt [, arg]])</code></a></h3>
+
+
+<p>
+This function is a generic interface to the garbage collector.
+It performs different functions according to its first argument, <code>opt</code>:
+
+<ul>
+
+<li><b>"<code>collect</code>": </b>
+Performs a full garbage-collection cycle.
+This is the default option.
+</li>
+
+<li><b>"<code>stop</code>": </b>
+Stops automatic execution of the garbage collector.
+The collector will run only when explicitly invoked,
+until a call to restart it.
+</li>
+
+<li><b>"<code>restart</code>": </b>
+Restarts automatic execution of the garbage collector.
+</li>
+
+<li><b>"<code>count</code>": </b>
+Returns the total memory in use by Lua in Kbytes.
+The value has a fractional part,
+so that it multiplied by 1024
+gives the exact number of bytes in use by Lua.
+</li>
+
+<li><b>"<code>step</code>": </b>
+Performs a garbage-collection step.
+The step "size" is controlled by <code>arg</code>.
+With a zero value,
+the collector will perform one basic (indivisible) step.
+For non-zero values,
+the collector will perform as if that amount of memory
+(in Kbytes) had been allocated by Lua.
+Returns <b>true</b> if the step finished a collection cycle.
+</li>
+
+<li><b>"<code>isrunning</code>": </b>
+Returns a boolean that tells whether the collector is running
+(i.e., not stopped).
+</li>
+
+<li><b>"<code>incremental</code>": </b>
+Change the collector mode to incremental.
+This option can be followed by three numbers:
+the garbage-collector pause,
+the step multiplier,
+and the step size (see <a href="#2.5.1">&sect;2.5.1</a>).
+A zero means to not change that value.
+</li>
+
+<li><b>"<code>generational</code>": </b>
+Change the collector mode to generational.
+This option can be followed by two numbers:
+the garbage-collector minor multiplier
+and the major multiplier (see <a href="#2.5.2">&sect;2.5.2</a>).
+A zero means to not change that value.
+</li>
+
+</ul><p>
+See <a href="#2.5">&sect;2.5</a> for more details about garbage collection
+and some of these options.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-dofile"><code>dofile ([filename])</code></a></h3>
+Opens the named file and executes its content as a Lua chunk.
+When called without arguments,
+<code>dofile</code> executes the content of the standard input (<code>stdin</code>).
+Returns all values returned by the chunk.
+In case of errors, <code>dofile</code> propagates the error
+to its caller.
+(That is, <code>dofile</code> does not run in protected mode.)
+
+
+
+
+<p>
+<hr><h3><a name="pdf-error"><code>error (message [, level])</code></a></h3>
+Raises an error (see <a href="#2.3">&sect;2.3</a>) with @{message} as the error object.
+This function never returns.
+
+
+<p>
+Usually, <code>error</code> adds some information about the error position
+at the beginning of the message, if the message is a string.
+The <code>level</code> argument specifies how to get the error position.
+With level&nbsp;1 (the default), the error position is where the
+<code>error</code> function was called.
+Level&nbsp;2 points the error to where the function
+that called <code>error</code> was called; and so on.
+Passing a level&nbsp;0 avoids the addition of error position information
+to the message.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-_G"><code>_G</code></a></h3>
+A global variable (not a function) that
+holds the global environment (see <a href="#2.2">&sect;2.2</a>).
+Lua itself does not use this variable;
+changing its value does not affect any environment,
+nor vice versa.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-getmetatable"><code>getmetatable (object)</code></a></h3>
+
+
+<p>
+If <code>object</code> does not have a metatable, returns <b>nil</b>.
+Otherwise,
+if the object's metatable has a <code>__metatable</code> field,
+returns the associated value.
+Otherwise, returns the metatable of the given object.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-ipairs"><code>ipairs (t)</code></a></h3>
+
+
+<p>
+Returns three values (an iterator function, the table <code>t</code>, and 0)
+so that the construction
+
+<pre>
+     for i,v in ipairs(t) do <em>body</em> end
+</pre><p>
+will iterate over the key&ndash;value pairs
+(<code>1,t[1]</code>), (<code>2,t[2]</code>), ...,
+up to the first absent index.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-load"><code>load (chunk [, chunkname [, mode [, env]]])</code></a></h3>
+
+
+<p>
+Loads a chunk.
+
+
+<p>
+If <code>chunk</code> is a string, the chunk is this string.
+If <code>chunk</code> is a function,
+<code>load</code> calls it repeatedly to get the chunk pieces.
+Each call to <code>chunk</code> must return a string that concatenates
+with previous results.
+A return of an empty string, <b>nil</b>, or no value signals the end of the chunk.
+
+
+<p>
+If there are no syntactic errors,
+<code>load</code> returns the compiled chunk as a function;
+otherwise, it returns <b>fail</b> plus the error message.
+
+
+<p>
+When you load a main chunk,
+the resulting function will always have exactly one upvalue,
+the <code>_ENV</code> variable (see <a href="#2.2">&sect;2.2</a>).
+However,
+when you load a binary chunk created from a function (see <a href="#pdf-string.dump"><code>string.dump</code></a>),
+the resulting function can have an arbitrary number of upvalues,
+and there is no guarantee that its first upvalue will be
+the <code>_ENV</code> variable.
+(A non-main function may not even have an <code>_ENV</code> upvalue.)
+
+
+<p>
+Regardless, if the resulting function has any upvalues,
+its first upvalue is set to the value of <code>env</code>,
+if that parameter is given,
+or to the value of the global environment.
+Other upvalues are initialized with <b>nil</b>.
+All upvalues are fresh, that is,
+they are not shared with any other function.
+
+
+<p>
+<code>chunkname</code> is used as the name of the chunk for error messages
+and debug information (see <a href="#4.7">&sect;4.7</a>).
+When absent,
+it defaults to <code>chunk</code>, if <code>chunk</code> is a string,
+or to "<code>=(load)</code>" otherwise.
+
+
+<p>
+The string <code>mode</code> controls whether the chunk can be text or binary
+(that is, a precompiled chunk).
+It may be the string "<code>b</code>" (only binary chunks),
+"<code>t</code>" (only text chunks),
+or "<code>bt</code>" (both binary and text).
+The default is "<code>bt</code>".
+
+
+<p>
+Lua does not check the consistency of binary chunks.
+Maliciously crafted binary chunks can crash
+the interpreter.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-loadfile"><code>loadfile ([filename [, mode [, env]]])</code></a></h3>
+
+
+<p>
+Similar to <a href="#pdf-load"><code>load</code></a>,
+but gets the chunk from file <code>filename</code>
+or from the standard input,
+if no file name is given.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-next"><code>next (table [, index])</code></a></h3>
+
+
+<p>
+Allows a program to traverse all fields of a table.
+Its first argument is a table and its second argument
+is an index in this table.
+A call to <code>next</code> returns the next index of the table
+and its associated value.
+When called with <b>nil</b> as its second argument,
+<code>next</code> returns an initial index
+and its associated value.
+When called with the last index,
+or with <b>nil</b> in an empty table,
+<code>next</code> returns <b>nil</b>.
+If the second argument is absent, then it is interpreted as <b>nil</b>.
+In particular,
+you can use <code>next(t)</code> to check whether a table is empty.
+
+
+<p>
+The order in which the indices are enumerated is not specified,
+<em>even for numeric indices</em>.
+(To traverse a table in numerical order,
+use a numerical <b>for</b>.)
+
+
+<p>
+The behavior of <code>next</code> is undefined if,
+during the traversal,
+you assign any value to a non-existent field in the table.
+You may however modify existing fields.
+In particular, you may set existing fields to nil.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-pairs"><code>pairs (t)</code></a></h3>
+
+
+<p>
+If <code>t</code> has a metamethod <code>__pairs</code>,
+calls it with <code>t</code> as argument and returns the first three
+results from the call.
+
+
+<p>
+Otherwise,
+returns three values: the <a href="#pdf-next"><code>next</code></a> function, the table <code>t</code>, and <b>nil</b>,
+so that the construction
+
+<pre>
+     for k,v in pairs(t) do <em>body</em> end
+</pre><p>
+will iterate over all key&ndash;value pairs of table <code>t</code>.
+
+
+<p>
+See function <a href="#pdf-next"><code>next</code></a> for the caveats of modifying
+the table during its traversal.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-pcall"><code>pcall (f [, arg1, &middot;&middot;&middot;])</code></a></h3>
+
+
+<p>
+Calls the function <code>f</code> with
+the given arguments in <em>protected mode</em>.
+This means that any error inside&nbsp;<code>f</code> is not propagated;
+instead, <code>pcall</code> catches the error
+and returns a status code.
+Its first result is the status code (a boolean),
+which is true if the call succeeds without errors.
+In such case, <code>pcall</code> also returns all results from the call,
+after this first result.
+In case of any error, <code>pcall</code> returns <b>false</b> plus the error object.
+Note that errors caught by <code>pcall</code> do not call a message handler.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-print"><code>print (&middot;&middot;&middot;)</code></a></h3>
+Receives any number of arguments
+and prints their values to <code>stdout</code>,
+converting each argument to a string
+following the same rules of <a href="#pdf-tostring"><code>tostring</code></a>.
+
+
+<p>
+The function <code>print</code> is not intended for formatted output,
+but only as a quick way to show a value,
+for instance for debugging.
+For complete control over the output,
+use <a href="#pdf-string.format"><code>string.format</code></a> and <a href="#pdf-io.write"><code>io.write</code></a>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-rawequal"><code>rawequal (v1, v2)</code></a></h3>
+Checks whether <code>v1</code> is equal to <code>v2</code>,
+without invoking the <code>__eq</code> metamethod.
+Returns a boolean.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-rawget"><code>rawget (table, index)</code></a></h3>
+Gets the real value of <code>table[index]</code>,
+without using the <code>__index</code> metavalue.
+<code>table</code> must be a table;
+<code>index</code> may be any value.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-rawlen"><code>rawlen (v)</code></a></h3>
+Returns the length of the object <code>v</code>,
+which must be a table or a string,
+without invoking the <code>__len</code> metamethod.
+Returns an integer.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-rawset"><code>rawset (table, index, value)</code></a></h3>
+Sets the real value of <code>table[index]</code> to <code>value</code>,
+without using the <code>__newindex</code> metavalue.
+<code>table</code> must be a table,
+<code>index</code> any value different from <b>nil</b> and NaN,
+and <code>value</code> any Lua value.
+
+
+<p>
+This function returns <code>table</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-select"><code>select (index, &middot;&middot;&middot;)</code></a></h3>
+
+
+<p>
+If <code>index</code> is a number,
+returns all arguments after argument number <code>index</code>;
+a negative number indexes from the end (-1 is the last argument).
+Otherwise, <code>index</code> must be the string <code>"#"</code>,
+and <code>select</code> returns the total number of extra arguments it received.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-setmetatable"><code>setmetatable (table, metatable)</code></a></h3>
+
+
+<p>
+Sets the metatable for the given table.
+If <code>metatable</code> is <b>nil</b>,
+removes the metatable of the given table.
+If the original metatable has a <code>__metatable</code> field,
+raises an error.
+
+
+<p>
+This function returns <code>table</code>.
+
+
+<p>
+To change the metatable of other types from Lua code,
+you must use the debug library (<a href="#6.10">&sect;6.10</a>).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-tonumber"><code>tonumber (e [, base])</code></a></h3>
+
+
+<p>
+When called with no <code>base</code>,
+<code>tonumber</code> tries to convert its argument to a number.
+If the argument is already a number or
+a string convertible to a number,
+then <code>tonumber</code> returns this number;
+otherwise, it returns <b>fail</b>.
+
+
+<p>
+The conversion of strings can result in integers or floats,
+according to the lexical conventions of Lua (see <a href="#3.1">&sect;3.1</a>).
+The string may have leading and trailing spaces and a sign.
+
+
+<p>
+When called with <code>base</code>,
+then <code>e</code> must be a string to be interpreted as
+an integer numeral in that base.
+The base may be any integer between 2 and 36, inclusive.
+In bases above&nbsp;10, the letter '<code>A</code>' (in either upper or lower case)
+represents&nbsp;10, '<code>B</code>' represents&nbsp;11, and so forth,
+with '<code>Z</code>' representing 35.
+If the string <code>e</code> is not a valid numeral in the given base,
+the function returns <b>fail</b>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-tostring"><code>tostring (v)</code></a></h3>
+
+
+<p>
+Receives a value of any type and
+converts it to a string in a human-readable format.
+
+
+<p>
+If the metatable of <code>v</code> has a <code>__tostring</code> field,
+then <code>tostring</code> calls the corresponding value
+with <code>v</code> as argument,
+and uses the result of the call as its result.
+Otherwise, if the metatable of <code>v</code> has a <code>__name</code> field
+with a string value,
+<code>tostring</code> may use that string in its final result.
+
+
+<p>
+For complete control of how numbers are converted,
+use <a href="#pdf-string.format"><code>string.format</code></a>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-type"><code>type (v)</code></a></h3>
+
+
+<p>
+Returns the type of its only argument, coded as a string.
+The possible results of this function are
+"<code>nil</code>" (a string, not the value <b>nil</b>),
+"<code>number</code>",
+"<code>string</code>",
+"<code>boolean</code>",
+"<code>table</code>",
+"<code>function</code>",
+"<code>thread</code>",
+and "<code>userdata</code>".
+
+
+
+
+<p>
+<hr><h3><a name="pdf-_VERSION"><code>_VERSION</code></a></h3>
+
+
+<p>
+A global variable (not a function) that
+holds a string containing the running Lua version.
+The current value of this variable is "<code>Lua 5.4</code>".
+
+
+
+
+<p>
+<hr><h3><a name="pdf-warn"><code>warn (msg1, &middot;&middot;&middot;)</code></a></h3>
+
+
+<p>
+Emits a warning with a message composed by the concatenation
+of all its arguments (which should be strings).
+
+
+<p>
+By convention,
+a one-piece message starting with '<code>@</code>'
+is intended to be a <em>control message</em>,
+which is a message to the warning system itself.
+In particular, the standard warning function in Lua
+recognizes the control messages "<code>@off</code>",
+to stop the emission of warnings,
+and "<code>@on</code>", to (re)start the emission;
+it ignores unknown control messages.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-xpcall"><code>xpcall (f, msgh [, arg1, &middot;&middot;&middot;])</code></a></h3>
+
+
+<p>
+This function is similar to <a href="#pdf-pcall"><code>pcall</code></a>,
+except that it sets a new message handler <code>msgh</code>.
+
+
+
+
+
+
+
+<h2>6.2 &ndash; <a name="6.2">Coroutine Manipulation</a></h2>
+
+<p>
+This library comprises the operations to manipulate coroutines,
+which come inside the table <a name="pdf-coroutine"><code>coroutine</code></a>.
+See <a href="#2.6">&sect;2.6</a> for a general description of coroutines.
+
+
+<p>
+<hr><h3><a name="pdf-coroutine.close"><code>coroutine.close (co)</code></a></h3>
+
+
+<p>
+Closes coroutine <code>co</code>,
+that is,
+closes all its pending to-be-closed variables
+and puts the coroutine in a dead state.
+The given coroutine must be dead or suspended.
+In case of error closing some variable,
+returns <b>false</b> plus the error object;
+otherwise returns <b>true</b>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-coroutine.create"><code>coroutine.create (f)</code></a></h3>
+
+
+<p>
+Creates a new coroutine, with body <code>f</code>.
+<code>f</code> must be a function.
+Returns this new coroutine,
+an object with type <code>"thread"</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-coroutine.isyieldable"><code>coroutine.isyieldable ([co])</code></a></h3>
+
+
+<p>
+Returns true when the coroutine <code>co</code> can yield.
+The default for <code>co</code> is the running coroutine.
+
+
+<p>
+A coroutine is yieldable if it is not the main thread and
+it is not inside a non-yieldable C&nbsp;function.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-coroutine.resume"><code>coroutine.resume (co [, val1, &middot;&middot;&middot;])</code></a></h3>
+
+
+<p>
+Starts or continues the execution of coroutine <code>co</code>.
+The first time you resume a coroutine,
+it starts running its body.
+The values <code>val1</code>, ... are passed
+as the arguments to the body function.
+If the coroutine has yielded,
+<code>resume</code> restarts it;
+the values <code>val1</code>, ... are passed
+as the results from the yield.
+
+
+<p>
+If the coroutine runs without any errors,
+<code>resume</code> returns <b>true</b> plus any values passed to <code>yield</code>
+(when the coroutine yields) or any values returned by the body function
+(when the coroutine terminates).
+If there is any error,
+<code>resume</code> returns <b>false</b> plus the error message.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-coroutine.running"><code>coroutine.running ()</code></a></h3>
+
+
+<p>
+Returns the running coroutine plus a boolean,
+true when the running coroutine is the main one.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-coroutine.status"><code>coroutine.status (co)</code></a></h3>
+
+
+<p>
+Returns the status of the coroutine <code>co</code>, as a string:
+<code>"running"</code>,
+if the coroutine is running
+(that is, it is the one that called <code>status</code>);
+<code>"suspended"</code>, if the coroutine is suspended in a call to <code>yield</code>,
+or if it has not started running yet;
+<code>"normal"</code> if the coroutine is active but not running
+(that is, it has resumed another coroutine);
+and <code>"dead"</code> if the coroutine has finished its body function,
+or if it has stopped with an error.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-coroutine.wrap"><code>coroutine.wrap (f)</code></a></h3>
+
+
+<p>
+Creates a new coroutine, with body <code>f</code>;
+<code>f</code> must be a function.
+Returns a function that resumes the coroutine each time it is called.
+Any arguments passed to this function behave as the
+extra arguments to <code>resume</code>.
+The function returns the same values returned by <code>resume</code>,
+except the first boolean.
+In case of error,
+the function closes the coroutine and propagates the error.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-coroutine.yield"><code>coroutine.yield (&middot;&middot;&middot;)</code></a></h3>
+
+
+<p>
+Suspends the execution of the calling coroutine.
+Any arguments to <code>yield</code> are passed as extra results to <code>resume</code>.
+
+
+
+
+
+
+
+<h2>6.3 &ndash; <a name="6.3">Modules</a></h2>
+
+<p>
+The package library provides basic
+facilities for loading modules in Lua.
+It exports one function directly in the global environment:
+<a href="#pdf-require"><code>require</code></a>.
+Everything else is exported in the table <a name="pdf-package"><code>package</code></a>.
+
+
+<p>
+<hr><h3><a name="pdf-require"><code>require (modname)</code></a></h3>
+
+
+<p>
+Loads the given module.
+The function starts by looking into the <a href="#pdf-package.loaded"><code>package.loaded</code></a> table
+to determine whether <code>modname</code> is already loaded.
+If it is, then <code>require</code> returns the value stored
+at <code>package.loaded[modname]</code>.
+(The absence of a second result in this case
+signals that this call did not have to load the module.)
+Otherwise, it tries to find a <em>loader</em> for the module.
+
+
+<p>
+To find a loader,
+<code>require</code> is guided by the table <a href="#pdf-package.searchers"><code>package.searchers</code></a>.
+Each item in this table is a search function,
+that searches for the module in a particular way.
+By changing this table,
+we can change how <code>require</code> looks for a module.
+The following explanation is based on the default configuration
+for <a href="#pdf-package.searchers"><code>package.searchers</code></a>.
+
+
+<p>
+First <code>require</code> queries <code>package.preload[modname]</code>.
+If it has a value,
+this value (which must be a function) is the loader.
+Otherwise <code>require</code> searches for a Lua loader using the
+path stored in <a href="#pdf-package.path"><code>package.path</code></a>.
+If that also fails, it searches for a C&nbsp;loader using the
+path stored in <a href="#pdf-package.cpath"><code>package.cpath</code></a>.
+If that also fails,
+it tries an <em>all-in-one</em> loader (see <a href="#pdf-package.searchers"><code>package.searchers</code></a>).
+
+
+<p>
+Once a loader is found,
+<code>require</code> calls the loader with two arguments:
+<code>modname</code> and an extra value,
+a <em>loader data</em>,
+also returned by the searcher.
+The loader data can be any value useful to the module;
+for the default searchers,
+it indicates where the loader was found.
+(For instance, if the loader came from a file,
+this extra value is the file path.)
+If the loader returns any non-nil value,
+<code>require</code> assigns the returned value to <code>package.loaded[modname]</code>.
+If the loader does not return a non-nil value and
+has not assigned any value to <code>package.loaded[modname]</code>,
+then <code>require</code> assigns <b>true</b> to this entry.
+In any case, <code>require</code> returns the
+final value of <code>package.loaded[modname]</code>.
+Besides that value, <code>require</code> also returns as a second result
+the loader data returned by the searcher,
+which indicates how <code>require</code> found the module.
+
+
+<p>
+If there is any error loading or running the module,
+or if it cannot find any loader for the module,
+then <code>require</code> raises an error.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-package.config"><code>package.config</code></a></h3>
+
+
+<p>
+A string describing some compile-time configurations for packages.
+This string is a sequence of lines:
+
+<ul>
+
+<li>The first line is the directory separator string.
+Default is '<code>\</code>' for Windows and '<code>/</code>' for all other systems.</li>
+
+<li>The second line is the character that separates templates in a path.
+Default is '<code>;</code>'.</li>
+
+<li>The third line is the string that marks the
+substitution points in a template.
+Default is '<code>?</code>'.</li>
+
+<li>The fourth line is a string that, in a path in Windows,
+is replaced by the executable's directory.
+Default is '<code>!</code>'.</li>
+
+<li>The fifth line is a mark to ignore all text after it
+when building the <code>luaopen_</code> function name.
+Default is '<code>-</code>'.</li>
+
+</ul>
+
+
+
+<p>
+<hr><h3><a name="pdf-package.cpath"><code>package.cpath</code></a></h3>
+
+
+<p>
+A string with the path used by <a href="#pdf-require"><code>require</code></a>
+to search for a C&nbsp;loader.
+
+
+<p>
+Lua initializes the C&nbsp;path <a href="#pdf-package.cpath"><code>package.cpath</code></a> in the same way
+it initializes the Lua path <a href="#pdf-package.path"><code>package.path</code></a>,
+using the environment variable <a name="pdf-LUA_CPATH_5_4"><code>LUA_CPATH_5_4</code></a>,
+or the environment variable <a name="pdf-LUA_CPATH"><code>LUA_CPATH</code></a>,
+or a default path defined in <code>luaconf.h</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-package.loaded"><code>package.loaded</code></a></h3>
+
+
+<p>
+A table used by <a href="#pdf-require"><code>require</code></a> to control which
+modules are already loaded.
+When you require a module <code>modname</code> and
+<code>package.loaded[modname]</code> is not false,
+<a href="#pdf-require"><code>require</code></a> simply returns the value stored there.
+
+
+<p>
+This variable is only a reference to the real table;
+assignments to this variable do not change the
+table used by <a href="#pdf-require"><code>require</code></a>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-package.loadlib"><code>package.loadlib (libname, funcname)</code></a></h3>
+
+
+<p>
+Dynamically links the host program with the C&nbsp;library <code>libname</code>.
+
+
+<p>
+If <code>funcname</code> is "<code>*</code>",
+then it only links with the library,
+making the symbols exported by the library
+available to other dynamically linked libraries.
+Otherwise,
+it looks for a function <code>funcname</code> inside the library
+and returns this function as a C&nbsp;function.
+So, <code>funcname</code> must follow the <a href="#lua_CFunction"><code>lua_CFunction</code></a> prototype
+(see <a href="#lua_CFunction"><code>lua_CFunction</code></a>).
+
+
+<p>
+This is a low-level function.
+It completely bypasses the package and module system.
+Unlike <a href="#pdf-require"><code>require</code></a>,
+it does not perform any path searching and
+does not automatically adds extensions.
+<code>libname</code> must be the complete file name of the C&nbsp;library,
+including if necessary a path and an extension.
+<code>funcname</code> must be the exact name exported by the C&nbsp;library
+(which may depend on the C&nbsp;compiler and linker used).
+
+
+<p>
+This function is not supported by Standard&nbsp;C.
+As such, it is only available on some platforms
+(Windows, Linux, Mac OS X, Solaris, BSD,
+plus other Unix systems that support the <code>dlfcn</code> standard).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-package.path"><code>package.path</code></a></h3>
+
+
+<p>
+A string with the path used by <a href="#pdf-require"><code>require</code></a>
+to search for a Lua loader.
+
+
+<p>
+At start-up, Lua initializes this variable with
+the value of the environment variable <a name="pdf-LUA_PATH_5_4"><code>LUA_PATH_5_4</code></a> or
+the environment variable <a name="pdf-LUA_PATH"><code>LUA_PATH</code></a> or
+with a default path defined in <code>luaconf.h</code>,
+if those environment variables are not defined.
+A "<code>;;</code>" in the value of the environment variable
+is replaced by the default path.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-package.preload"><code>package.preload</code></a></h3>
+
+
+<p>
+A table to store loaders for specific modules
+(see <a href="#pdf-require"><code>require</code></a>).
+
+
+<p>
+This variable is only a reference to the real table;
+assignments to this variable do not change the
+table used by <a href="#pdf-require"><code>require</code></a>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-package.searchers"><code>package.searchers</code></a></h3>
+
+
+<p>
+A table used by <a href="#pdf-require"><code>require</code></a> to control how to find modules.
+
+
+<p>
+Each entry in this table is a <em>searcher function</em>.
+When looking for a module,
+<a href="#pdf-require"><code>require</code></a> calls each of these searchers in ascending order,
+with the module name (the argument given to <a href="#pdf-require"><code>require</code></a>) as its
+sole argument.
+If the searcher finds the module,
+it returns another function, the module <em>loader</em>,
+plus an extra value, a <em>loader data</em>,
+that will be passed to that loader and
+returned as a second result by <a href="#pdf-require"><code>require</code></a>.
+If it cannot find the module,
+it returns a string explaining why
+(or <b>nil</b> if it has nothing to say).
+
+
+<p>
+Lua initializes this table with four searcher functions.
+
+
+<p>
+The first searcher simply looks for a loader in the
+<a href="#pdf-package.preload"><code>package.preload</code></a> table.
+
+
+<p>
+The second searcher looks for a loader as a Lua library,
+using the path stored at <a href="#pdf-package.path"><code>package.path</code></a>.
+The search is done as described in function <a href="#pdf-package.searchpath"><code>package.searchpath</code></a>.
+
+
+<p>
+The third searcher looks for a loader as a C&nbsp;library,
+using the path given by the variable <a href="#pdf-package.cpath"><code>package.cpath</code></a>.
+Again,
+the search is done as described in function <a href="#pdf-package.searchpath"><code>package.searchpath</code></a>.
+For instance,
+if the C&nbsp;path is the string
+
+<pre>
+     "./?.so;./?.dll;/usr/local/?/init.so"
+</pre><p>
+the searcher for module <code>foo</code>
+will try to open the files <code>./foo.so</code>, <code>./foo.dll</code>,
+and <code>/usr/local/foo/init.so</code>, in that order.
+Once it finds a C&nbsp;library,
+this searcher first uses a dynamic link facility to link the
+application with the library.
+Then it tries to find a C&nbsp;function inside the library to
+be used as the loader.
+The name of this C&nbsp;function is the string "<code>luaopen_</code>"
+concatenated with a copy of the module name where each dot
+is replaced by an underscore.
+Moreover, if the module name has a hyphen,
+its suffix after (and including) the first hyphen is removed.
+For instance, if the module name is <code>a.b.c-v2.1</code>,
+the function name will be <code>luaopen_a_b_c</code>.
+
+
+<p>
+The fourth searcher tries an <em>all-in-one loader</em>.
+It searches the C&nbsp;path for a library for
+the root name of the given module.
+For instance, when requiring <code>a.b.c</code>,
+it will search for a C&nbsp;library for <code>a</code>.
+If found, it looks into it for an open function for
+the submodule;
+in our example, that would be <code>luaopen_a_b_c</code>.
+With this facility, a package can pack several C&nbsp;submodules
+into one single library,
+with each submodule keeping its original open function.
+
+
+<p>
+All searchers except the first one (preload) return as the extra value
+the file path where the module was found,
+as returned by <a href="#pdf-package.searchpath"><code>package.searchpath</code></a>.
+The first searcher always returns the string "<code>:preload:</code>".
+
+
+<p>
+Searchers should raise no errors and have no side effects in Lua.
+(They may have side effects in C,
+for instance by linking the application with a library.)
+
+
+
+
+<p>
+<hr><h3><a name="pdf-package.searchpath"><code>package.searchpath (name, path [, sep [, rep]])</code></a></h3>
+
+
+<p>
+Searches for the given <code>name</code> in the given <code>path</code>.
+
+
+<p>
+A path is a string containing a sequence of
+<em>templates</em> separated by semicolons.
+For each template,
+the function replaces each interrogation mark (if any)
+in the template with a copy of <code>name</code>
+wherein all occurrences of <code>sep</code>
+(a dot, by default)
+were replaced by <code>rep</code>
+(the system's directory separator, by default),
+and then tries to open the resulting file name.
+
+
+<p>
+For instance, if the path is the string
+
+<pre>
+     "./?.lua;./?.lc;/usr/local/?/init.lua"
+</pre><p>
+the search for the name <code>foo.a</code>
+will try to open the files
+<code>./foo/a.lua</code>, <code>./foo/a.lc</code>, and
+<code>/usr/local/foo/a/init.lua</code>, in that order.
+
+
+<p>
+Returns the resulting name of the first file that it can
+open in read mode (after closing the file),
+or <b>fail</b> plus an error message if none succeeds.
+(This error message lists all file names it tried to open.)
+
+
+
+
+
+
+
+<h2>6.4 &ndash; <a name="6.4">String Manipulation</a></h2>
+
+
+
+<p>
+This library provides generic functions for string manipulation,
+such as finding and extracting substrings, and pattern matching.
+When indexing a string in Lua, the first character is at position&nbsp;1
+(not at&nbsp;0, as in C).
+Indices are allowed to be negative and are interpreted as indexing backwards,
+from the end of the string.
+Thus, the last character is at position -1, and so on.
+
+
+<p>
+The string library provides all its functions inside the table
+<a name="pdf-string"><code>string</code></a>.
+It also sets a metatable for strings
+where the <code>__index</code> field points to the <code>string</code> table.
+Therefore, you can use the string functions in object-oriented style.
+For instance, <code>string.byte(s,i)</code>
+can be written as <code>s:byte(i)</code>.
+
+
+<p>
+The string library assumes one-byte character encodings.
+
+
+<p>
+<hr><h3><a name="pdf-string.byte"><code>string.byte (s [, i [, j]])</code></a></h3>
+Returns the internal numeric codes of the characters <code>s[i]</code>,
+<code>s[i+1]</code>, ..., <code>s[j]</code>.
+The default value for <code>i</code> is&nbsp;1;
+the default value for <code>j</code> is&nbsp;<code>i</code>.
+These indices are corrected
+following the same rules of function <a href="#pdf-string.sub"><code>string.sub</code></a>.
+
+
+<p>
+Numeric codes are not necessarily portable across platforms.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-string.char"><code>string.char (&middot;&middot;&middot;)</code></a></h3>
+Receives zero or more integers.
+Returns a string with length equal to the number of arguments,
+in which each character has the internal numeric code equal
+to its corresponding argument.
+
+
+<p>
+Numeric codes are not necessarily portable across platforms.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-string.dump"><code>string.dump (function [, strip])</code></a></h3>
+
+
+<p>
+Returns a string containing a binary representation
+(a <em>binary chunk</em>)
+of the given function,
+so that a later <a href="#pdf-load"><code>load</code></a> on this string returns
+a copy of the function (but with new upvalues).
+If <code>strip</code> is a true value,
+the binary representation may not include all debug information
+about the function,
+to save space.
+
+
+<p>
+Functions with upvalues have only their number of upvalues saved.
+When (re)loaded,
+those upvalues receive fresh instances.
+(See the <a href="#pdf-load"><code>load</code></a> function for details about
+how these upvalues are initialized.
+You can use the debug library to serialize
+and reload the upvalues of a function
+in a way adequate to your needs.)
+
+
+
+
+<p>
+<hr><h3><a name="pdf-string.find"><code>string.find (s, pattern [, init [, plain]])</code></a></h3>
+
+
+<p>
+Looks for the first match of
+<code>pattern</code> (see <a href="#6.4.1">&sect;6.4.1</a>) in the string <code>s</code>.
+If it finds a match, then <code>find</code> returns the indices of&nbsp;<code>s</code>
+where this occurrence starts and ends;
+otherwise, it returns <b>fail</b>.
+A third, optional numeric argument <code>init</code> specifies
+where to start the search;
+its default value is&nbsp;1 and can be negative.
+A value of <b>true</b> as a fourth, optional argument <code>plain</code>
+turns off the pattern matching facilities,
+so the function does a plain "find substring" operation,
+with no characters in <code>pattern</code> being considered magic.
+
+
+<p>
+If the pattern has captures,
+then in a successful match
+the captured values are also returned,
+after the two indices.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-string.format"><code>string.format (formatstring, &middot;&middot;&middot;)</code></a></h3>
+
+
+<p>
+Returns a formatted version of its variable number of arguments
+following the description given in its first argument,
+which must be a string.
+The format string follows the same rules as the ISO&nbsp;C function <code>sprintf</code>.
+The only differences are that the conversion specifiers and modifiers
+<code>*</code>, <code>h</code>, <code>L</code>, <code>l</code>, and <code>n</code> are not supported
+and that there is an extra specifier, <code>q</code>.
+
+
+<p>
+The specifier <code>q</code> formats booleans, nil, numbers, and strings
+in a way that the result is a valid constant in Lua source code.
+Booleans and nil are written in the obvious way
+(<code>true</code>, <code>false</code>, <code>nil</code>).
+Floats are written in hexadecimal,
+to preserve full precision.
+A string is written between double quotes,
+using escape sequences when necessary to ensure that
+it can safely be read back by the Lua interpreter.
+For instance, the call
+
+<pre>
+     string.format('%q', 'a string with "quotes" and \n new line')
+</pre><p>
+may produce the string:
+
+<pre>
+     "a string with \"quotes\" and \
+      new line"
+</pre><p>
+This specifier does not support modifiers (flags, width, length).
+
+
+<p>
+The conversion specifiers
+<code>A</code>, <code>a</code>, <code>E</code>, <code>e</code>, <code>f</code>,
+<code>G</code>, and <code>g</code> all expect a number as argument.
+The specifiers <code>c</code>, <code>d</code>,
+<code>i</code>, <code>o</code>, <code>u</code>, <code>X</code>, and <code>x</code>
+expect an integer.
+When Lua is compiled with a C89 compiler,
+the specifiers <code>A</code> and <code>a</code> (hexadecimal floats)
+do not support modifiers.
+
+
+<p>
+The specifier <code>s</code> expects a string;
+if its argument is not a string,
+it is converted to one following the same rules of <a href="#pdf-tostring"><code>tostring</code></a>.
+If the specifier has any modifier,
+the corresponding string argument should not contain embedded zeros.
+
+
+<p>
+The specifier <code>p</code> formats the pointer
+returned by <a href="#lua_topointer"><code>lua_topointer</code></a>.
+That gives a unique string identifier for tables, userdata,
+threads, strings, and functions.
+For other values (numbers, nil, booleans),
+this specifier results in a string representing
+the pointer <code>NULL</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-string.gmatch"><code>string.gmatch (s, pattern [, init])</code></a></h3>
+Returns an iterator function that,
+each time it is called,
+returns the next captures from <code>pattern</code> (see <a href="#6.4.1">&sect;6.4.1</a>)
+over the string <code>s</code>.
+If <code>pattern</code> specifies no captures,
+then the whole match is produced in each call.
+A third, optional numeric argument <code>init</code> specifies
+where to start the search;
+its default value is&nbsp;1 and can be negative.
+
+
+<p>
+As an example, the following loop
+will iterate over all the words from string <code>s</code>,
+printing one per line:
+
+<pre>
+     s = "hello world from Lua"
+     for w in string.gmatch(s, "%a+") do
+       print(w)
+     end
+</pre><p>
+The next example collects all pairs <code>key=value</code> from the
+given string into a table:
+
+<pre>
+     t = {}
+     s = "from=world, to=Lua"
+     for k, v in string.gmatch(s, "(%w+)=(%w+)") do
+       t[k] = v
+     end
+</pre>
+
+<p>
+For this function, a caret '<code>^</code>' at the start of a pattern does not
+work as an anchor, as this would prevent the iteration.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-string.gsub"><code>string.gsub (s, pattern, repl [, n])</code></a></h3>
+Returns a copy of <code>s</code>
+in which all (or the first <code>n</code>, if given)
+occurrences of the <code>pattern</code> (see <a href="#6.4.1">&sect;6.4.1</a>) have been
+replaced by a replacement string specified by <code>repl</code>,
+which can be a string, a table, or a function.
+<code>gsub</code> also returns, as its second value,
+the total number of matches that occurred.
+The name <code>gsub</code> comes from <em>Global SUBstitution</em>.
+
+
+<p>
+If <code>repl</code> is a string, then its value is used for replacement.
+The character&nbsp;<code>%</code> works as an escape character:
+any sequence in <code>repl</code> of the form <code>%<em>d</em></code>,
+with <em>d</em> between 1 and 9,
+stands for the value of the <em>d</em>-th captured substring;
+the sequence <code>%0</code> stands for the whole match;
+the sequence <code>%%</code> stands for a single&nbsp;<code>%</code>.
+
+
+<p>
+If <code>repl</code> is a table, then the table is queried for every match,
+using the first capture as the key.
+
+
+<p>
+If <code>repl</code> is a function, then this function is called every time a
+match occurs, with all captured substrings passed as arguments,
+in order.
+
+
+<p>
+In any case,
+if the pattern specifies no captures,
+then it behaves as if the whole pattern was inside a capture.
+
+
+<p>
+If the value returned by the table query or by the function call
+is a string or a number,
+then it is used as the replacement string;
+otherwise, if it is <b>false</b> or <b>nil</b>,
+then there is no replacement
+(that is, the original match is kept in the string).
+
+
+<p>
+Here are some examples:
+
+<pre>
+     x = string.gsub("hello world", "(%w+)", "%1 %1")
+     --&gt; x="hello hello world world"
+     
+     x = string.gsub("hello world", "%w+", "%0 %0", 1)
+     --&gt; x="hello hello world"
+     
+     x = string.gsub("hello world from Lua", "(%w+)%s*(%w+)", "%2 %1")
+     --&gt; x="world hello Lua from"
+     
+     x = string.gsub("home = $HOME, user = $USER", "%$(%w+)", os.getenv)
+     --&gt; x="home = /home/roberto, user = roberto"
+     
+     x = string.gsub("4+5 = $return 4+5$", "%$(.-)%$", function (s)
+           return load(s)()
+         end)
+     --&gt; x="4+5 = 9"
+     
+     local t = {name="lua", version="5.4"}
+     x = string.gsub("$name-$version.tar.gz", "%$(%w+)", t)
+     --&gt; x="lua-5.4.tar.gz"
+</pre>
+
+
+
+<p>
+<hr><h3><a name="pdf-string.len"><code>string.len (s)</code></a></h3>
+
+
+<p>
+Receives a string and returns its length.
+The empty string <code>""</code> has length 0.
+Embedded zeros are counted,
+so <code>"a\000bc\000"</code> has length 5.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-string.lower"><code>string.lower (s)</code></a></h3>
+
+
+<p>
+Receives a string and returns a copy of this string with all
+uppercase letters changed to lowercase.
+All other characters are left unchanged.
+The definition of what an uppercase letter is depends on the current locale.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-string.match"><code>string.match (s, pattern [, init])</code></a></h3>
+
+
+<p>
+Looks for the first <em>match</em> of
+the <code>pattern</code> (see <a href="#6.4.1">&sect;6.4.1</a>) in the string <code>s</code>.
+If it finds one, then <code>match</code> returns
+the captures from the pattern;
+otherwise it returns <b>fail</b>.
+If <code>pattern</code> specifies no captures,
+then the whole match is returned.
+A third, optional numeric argument <code>init</code> specifies
+where to start the search;
+its default value is&nbsp;1 and can be negative.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-string.pack"><code>string.pack (fmt, v1, v2, &middot;&middot;&middot;)</code></a></h3>
+
+
+<p>
+Returns a binary string containing the values <code>v1</code>, <code>v2</code>, etc.
+serialized in binary form (packed)
+according to the format string <code>fmt</code> (see <a href="#6.4.2">&sect;6.4.2</a>).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-string.packsize"><code>string.packsize (fmt)</code></a></h3>
+
+
+<p>
+Returns the size of a string resulting from <a href="#pdf-string.pack"><code>string.pack</code></a>
+with the given format.
+The format string cannot have the variable-length options
+'<code>s</code>' or '<code>z</code>' (see <a href="#6.4.2">&sect;6.4.2</a>).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-string.rep"><code>string.rep (s, n [, sep])</code></a></h3>
+
+
+<p>
+Returns a string that is the concatenation of <code>n</code> copies of
+the string <code>s</code> separated by the string <code>sep</code>.
+The default value for <code>sep</code> is the empty string
+(that is, no separator).
+Returns the empty string if <code>n</code> is not positive.
+
+
+<p>
+(Note that it is very easy to exhaust the memory of your machine
+with a single call to this function.)
+
+
+
+
+<p>
+<hr><h3><a name="pdf-string.reverse"><code>string.reverse (s)</code></a></h3>
+
+
+<p>
+Returns a string that is the string <code>s</code> reversed.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-string.sub"><code>string.sub (s, i [, j])</code></a></h3>
+
+
+<p>
+Returns the substring of <code>s</code> that
+starts at <code>i</code>  and continues until <code>j</code>;
+<code>i</code> and <code>j</code> can be negative.
+If <code>j</code> is absent, then it is assumed to be equal to -1
+(which is the same as the string length).
+In particular,
+the call <code>string.sub(s,1,j)</code> returns a prefix of <code>s</code>
+with length <code>j</code>,
+and <code>string.sub(s, -i)</code> (for a positive <code>i</code>)
+returns a suffix of <code>s</code>
+with length <code>i</code>.
+
+
+<p>
+If, after the translation of negative indices,
+<code>i</code> is less than 1,
+it is corrected to 1.
+If <code>j</code> is greater than the string length,
+it is corrected to that length.
+If, after these corrections,
+<code>i</code> is greater than <code>j</code>,
+the function returns the empty string.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-string.unpack"><code>string.unpack (fmt, s [, pos])</code></a></h3>
+
+
+<p>
+Returns the values packed in string <code>s</code> (see <a href="#pdf-string.pack"><code>string.pack</code></a>)
+according to the format string <code>fmt</code> (see <a href="#6.4.2">&sect;6.4.2</a>).
+An optional <code>pos</code> marks where
+to start reading in <code>s</code> (default is 1).
+After the read values,
+this function also returns the index of the first unread byte in <code>s</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-string.upper"><code>string.upper (s)</code></a></h3>
+
+
+<p>
+Receives a string and returns a copy of this string with all
+lowercase letters changed to uppercase.
+All other characters are left unchanged.
+The definition of what a lowercase letter is depends on the current locale.
+
+
+
+
+
+
+
+<h3>6.4.1 &ndash; <a name="6.4.1">Patterns</a></h3>
+
+
+
+<p>
+Patterns in Lua are described by regular strings,
+which are interpreted as patterns by the pattern-matching functions
+<a href="#pdf-string.find"><code>string.find</code></a>,
+<a href="#pdf-string.gmatch"><code>string.gmatch</code></a>,
+<a href="#pdf-string.gsub"><code>string.gsub</code></a>,
+and <a href="#pdf-string.match"><code>string.match</code></a>.
+This section describes the syntax and the meaning
+(that is, what they match) of these strings.
+
+
+
+
+
+<h4>Character Class:</h4><p>
+A <em>character class</em> is used to represent a set of characters.
+The following combinations are allowed in describing a character class:
+
+<ul>
+
+<li><b><em>x</em>: </b>
+(where <em>x</em> is not one of the <em>magic characters</em>
+<code>^$()%.[]*+-?</code>)
+represents the character <em>x</em> itself.
+</li>
+
+<li><b><code>.</code>: </b> (a dot) represents all characters.</li>
+
+<li><b><code>%a</code>: </b> represents all letters.</li>
+
+<li><b><code>%c</code>: </b> represents all control characters.</li>
+
+<li><b><code>%d</code>: </b> represents all digits.</li>
+
+<li><b><code>%g</code>: </b> represents all printable characters except space.</li>
+
+<li><b><code>%l</code>: </b> represents all lowercase letters.</li>
+
+<li><b><code>%p</code>: </b> represents all punctuation characters.</li>
+
+<li><b><code>%s</code>: </b> represents all space characters.</li>
+
+<li><b><code>%u</code>: </b> represents all uppercase letters.</li>
+
+<li><b><code>%w</code>: </b> represents all alphanumeric characters.</li>
+
+<li><b><code>%x</code>: </b> represents all hexadecimal digits.</li>
+
+<li><b><code>%<em>x</em></code>: </b> (where <em>x</em> is any non-alphanumeric character)
+represents the character <em>x</em>.
+This is the standard way to escape the magic characters.
+Any non-alphanumeric character
+(including all punctuation characters, even the non-magical)
+can be preceded by a '<code>%</code>' to represent itself in a pattern.
+</li>
+
+<li><b><code>[<em>set</em>]</code>: </b>
+represents the class which is the union of all
+characters in <em>set</em>.
+A range of characters can be specified by
+separating the end characters of the range,
+in ascending order, with a '<code>-</code>'.
+All classes <code>%</code><em>x</em> described above can also be used as
+components in <em>set</em>.
+All other characters in <em>set</em> represent themselves.
+For example, <code>[%w_]</code> (or <code>[_%w]</code>)
+represents all alphanumeric characters plus the underscore,
+<code>[0-7]</code> represents the octal digits,
+and <code>[0-7%l%-]</code> represents the octal digits plus
+the lowercase letters plus the '<code>-</code>' character.
+
+
+<p>
+You can put a closing square bracket in a set
+by positioning it as the first character in the set.
+You can put a hyphen in a set
+by positioning it as the first or the last character in the set.
+(You can also use an escape for both cases.)
+
+
+<p>
+The interaction between ranges and classes is not defined.
+Therefore, patterns like <code>[%a-z]</code> or <code>[a-%%]</code>
+have no meaning.
+</li>
+
+<li><b><code>[^<em>set</em>]</code>: </b>
+represents the complement of <em>set</em>,
+where <em>set</em> is interpreted as above.
+</li>
+
+</ul><p>
+For all classes represented by single letters (<code>%a</code>, <code>%c</code>, etc.),
+the corresponding uppercase letter represents the complement of the class.
+For instance, <code>%S</code> represents all non-space characters.
+
+
+<p>
+The definitions of letter, space, and other character groups
+depend on the current locale.
+In particular, the class <code>[a-z]</code> may not be equivalent to <code>%l</code>.
+
+
+
+
+
+<h4>Pattern Item:</h4><p>
+A <em>pattern item</em> can be
+
+<ul>
+
+<li>
+a single character class,
+which matches any single character in the class;
+</li>
+
+<li>
+a single character class followed by '<code>*</code>',
+which matches sequences of zero or more characters in the class.
+These repetition items will always match the longest possible sequence;
+</li>
+
+<li>
+a single character class followed by '<code>+</code>',
+which matches sequences of one or more characters in the class.
+These repetition items will always match the longest possible sequence;
+</li>
+
+<li>
+a single character class followed by '<code>-</code>',
+which also matches sequences of zero or more characters in the class.
+Unlike '<code>*</code>',
+these repetition items will always match the shortest possible sequence;
+</li>
+
+<li>
+a single character class followed by '<code>?</code>',
+which matches zero or one occurrence of a character in the class.
+It always matches one occurrence if possible;
+</li>
+
+<li>
+<code>%<em>n</em></code>, for <em>n</em> between 1 and 9;
+such item matches a substring equal to the <em>n</em>-th captured string
+(see below);
+</li>
+
+<li>
+<code>%b<em>xy</em></code>, where <em>x</em> and <em>y</em> are two distinct characters;
+such item matches strings that start with&nbsp;<em>x</em>, end with&nbsp;<em>y</em>,
+and where the <em>x</em> and <em>y</em> are <em>balanced</em>.
+This means that, if one reads the string from left to right,
+counting <em>+1</em> for an <em>x</em> and <em>-1</em> for a <em>y</em>,
+the ending <em>y</em> is the first <em>y</em> where the count reaches 0.
+For instance, the item <code>%b()</code> matches expressions with
+balanced parentheses.
+</li>
+
+<li>
+<code>%f[<em>set</em>]</code>, a <em>frontier pattern</em>;
+such item matches an empty string at any position such that
+the next character belongs to <em>set</em>
+and the previous character does not belong to <em>set</em>.
+The set <em>set</em> is interpreted as previously described.
+The beginning and the end of the subject are handled as if
+they were the character '<code>\0</code>'.
+</li>
+
+</ul>
+
+
+
+
+<h4>Pattern:</h4><p>
+A <em>pattern</em> is a sequence of pattern items.
+A caret '<code>^</code>' at the beginning of a pattern anchors the match at the
+beginning of the subject string.
+A '<code>$</code>' at the end of a pattern anchors the match at the
+end of the subject string.
+At other positions,
+'<code>^</code>' and '<code>$</code>' have no special meaning and represent themselves.
+
+
+
+
+
+<h4>Captures:</h4><p>
+A pattern can contain sub-patterns enclosed in parentheses;
+they describe <em>captures</em>.
+When a match succeeds, the substrings of the subject string
+that match captures are stored (<em>captured</em>) for future use.
+Captures are numbered according to their left parentheses.
+For instance, in the pattern <code>"(a*(.)%w(%s*))"</code>,
+the part of the string matching <code>"a*(.)%w(%s*)"</code> is
+stored as the first capture, and therefore has number&nbsp;1;
+the character matching "<code>.</code>" is captured with number&nbsp;2,
+and the part matching "<code>%s*</code>" has number&nbsp;3.
+
+
+<p>
+As a special case, the capture <code>()</code> captures
+the current string position (a number).
+For instance, if we apply the pattern <code>"()aa()"</code> on the
+string <code>"flaaap"</code>, there will be two captures: 3&nbsp;and&nbsp;5.
+
+
+
+
+
+<h4>Multiple matches:</h4><p>
+The function <a href="#pdf-string.gsub"><code>string.gsub</code></a> and the iterator <a href="#pdf-string.gmatch"><code>string.gmatch</code></a>
+match multiple occurrences of the given pattern in the subject.
+For these functions,
+a new match is considered valid only
+if it ends at least one byte after the end of the previous match.
+In other words, the pattern machine never accepts the
+empty string as a match immediately after another match.
+As an example,
+consider the results of the following code:
+
+<pre>
+     &gt; string.gsub("abc", "()a*()", print);
+     --&gt; 1   2
+     --&gt; 3   3
+     --&gt; 4   4
+</pre><p>
+The second and third results come from Lua matching an empty
+string after '<code>b</code>' and another one after '<code>c</code>'.
+Lua does not match an empty string after '<code>a</code>',
+because it would end at the same position of the previous match.
+
+
+
+
+
+
+
+<h3>6.4.2 &ndash; <a name="6.4.2">Format Strings for Pack and Unpack</a></h3>
+
+<p>
+The first argument to <a href="#pdf-string.pack"><code>string.pack</code></a>,
+<a href="#pdf-string.packsize"><code>string.packsize</code></a>, and <a href="#pdf-string.unpack"><code>string.unpack</code></a>
+is a format string,
+which describes the layout of the structure being created or read.
+
+
+<p>
+A format string is a sequence of conversion options.
+The conversion options are as follows:
+
+<ul>
+<li><b><code>&lt;</code>: </b>sets little endian</li>
+<li><b><code>&gt;</code>: </b>sets big endian</li>
+<li><b><code>=</code>: </b>sets native endian</li>
+<li><b><code>![<em>n</em>]</code>: </b>sets maximum alignment to <code>n</code>
+(default is native alignment)</li>
+<li><b><code>b</code>: </b>a signed byte (<code>char</code>)</li>
+<li><b><code>B</code>: </b>an unsigned byte (<code>char</code>)</li>
+<li><b><code>h</code>: </b>a signed <code>short</code> (native size)</li>
+<li><b><code>H</code>: </b>an unsigned <code>short</code> (native size)</li>
+<li><b><code>l</code>: </b>a signed <code>long</code> (native size)</li>
+<li><b><code>L</code>: </b>an unsigned <code>long</code> (native size)</li>
+<li><b><code>j</code>: </b>a <code>lua_Integer</code></li>
+<li><b><code>J</code>: </b>a <code>lua_Unsigned</code></li>
+<li><b><code>T</code>: </b>a <code>size_t</code> (native size)</li>
+<li><b><code>i[<em>n</em>]</code>: </b>a signed <code>int</code> with <code>n</code> bytes
+(default is native size)</li>
+<li><b><code>I[<em>n</em>]</code>: </b>an unsigned <code>int</code> with <code>n</code> bytes
+(default is native size)</li>
+<li><b><code>f</code>: </b>a <code>float</code> (native size)</li>
+<li><b><code>d</code>: </b>a <code>double</code> (native size)</li>
+<li><b><code>n</code>: </b>a <code>lua_Number</code></li>
+<li><b><code>c<em>n</em></code>: </b>a fixed-sized string with <code>n</code> bytes</li>
+<li><b><code>z</code>: </b>a zero-terminated string</li>
+<li><b><code>s[<em>n</em>]</code>: </b>a string preceded by its length
+coded as an unsigned integer with <code>n</code> bytes
+(default is a <code>size_t</code>)</li>
+<li><b><code>x</code>: </b>one byte of padding</li>
+<li><b><code>X<em>op</em></code>: </b>an empty item that aligns
+according to option <code>op</code>
+(which is otherwise ignored)</li>
+<li><b>'<code> </code>': </b>(space) ignored</li>
+</ul><p>
+(A "<code>[<em>n</em>]</code>" means an optional integral numeral.)
+Except for padding, spaces, and configurations
+(options "<code>xX &lt;=&gt;!</code>"),
+each option corresponds to an argument in <a href="#pdf-string.pack"><code>string.pack</code></a>
+or a result in <a href="#pdf-string.unpack"><code>string.unpack</code></a>.
+
+
+<p>
+For options "<code>!<em>n</em></code>", "<code>s<em>n</em></code>", "<code>i<em>n</em></code>", and "<code>I<em>n</em></code>",
+<code>n</code> can be any integer between 1 and 16.
+All integral options check overflows;
+<a href="#pdf-string.pack"><code>string.pack</code></a> checks whether the given value fits in the given size;
+<a href="#pdf-string.unpack"><code>string.unpack</code></a> checks whether the read value fits in a Lua integer.
+For the unsigned options,
+Lua integers are treated as unsigned values too.
+
+
+<p>
+Any format string starts as if prefixed by "<code>!1=</code>",
+that is,
+with maximum alignment of 1 (no alignment)
+and native endianness.
+
+
+<p>
+Native endianness assumes that the whole system is
+either big or little endian.
+The packing functions will not emulate correctly the behavior
+of mixed-endian formats.
+
+
+<p>
+Alignment works as follows:
+For each option,
+the format gets extra padding until the data starts
+at an offset that is a multiple of the minimum between the
+option size and the maximum alignment;
+this minimum must be a power of 2.
+Options "<code>c</code>" and "<code>z</code>" are not aligned;
+option "<code>s</code>" follows the alignment of its starting integer.
+
+
+<p>
+All padding is filled with zeros by <a href="#pdf-string.pack"><code>string.pack</code></a>
+and ignored by <a href="#pdf-string.unpack"><code>string.unpack</code></a>.
+
+
+
+
+
+
+
+<h2>6.5 &ndash; <a name="6.5">UTF-8 Support</a></h2>
+
+<p>
+This library provides basic support for UTF-8 encoding.
+It provides all its functions inside the table <a name="pdf-utf8"><code>utf8</code></a>.
+This library does not provide any support for Unicode other
+than the handling of the encoding.
+Any operation that needs the meaning of a character,
+such as character classification, is outside its scope.
+
+
+<p>
+Unless stated otherwise,
+all functions that expect a byte position as a parameter
+assume that the given position is either the start of a byte sequence
+or one plus the length of the subject string.
+As in the string library,
+negative indices count from the end of the string.
+
+
+<p>
+Functions that create byte sequences
+accept all values up to <code>0x7FFFFFFF</code>,
+as defined in the original UTF-8 specification;
+that implies byte sequences of up to six bytes.
+
+
+<p>
+Functions that interpret byte sequences only accept
+valid sequences (well formed and not overlong).
+By default, they only accept byte sequences
+that result in valid Unicode code points,
+rejecting values greater than <code>10FFFF</code> and surrogates.
+A boolean argument <code>lax</code>, when available,
+lifts these checks,
+so that all values up to <code>0x7FFFFFFF</code> are accepted.
+(Not well formed and overlong sequences are still rejected.)
+
+
+<p>
+<hr><h3><a name="pdf-utf8.char"><code>utf8.char (&middot;&middot;&middot;)</code></a></h3>
+
+
+<p>
+Receives zero or more integers,
+converts each one to its corresponding UTF-8 byte sequence
+and returns a string with the concatenation of all these sequences.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-utf8.charpattern"><code>utf8.charpattern</code></a></h3>
+
+
+<p>
+The pattern (a string, not a function) "<code>[\0-\x7F\xC2-\xFD][\x80-\xBF]*</code>"
+(see <a href="#6.4.1">&sect;6.4.1</a>),
+which matches exactly one UTF-8 byte sequence,
+assuming that the subject is a valid UTF-8 string.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-utf8.codes"><code>utf8.codes (s [, lax])</code></a></h3>
+
+
+<p>
+Returns values so that the construction
+
+<pre>
+     for p, c in utf8.codes(s) do <em>body</em> end
+</pre><p>
+will iterate over all UTF-8 characters in string <code>s</code>,
+with <code>p</code> being the position (in bytes) and <code>c</code> the code point
+of each character.
+It raises an error if it meets any invalid byte sequence.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-utf8.codepoint"><code>utf8.codepoint (s [, i [, j [, lax]]])</code></a></h3>
+
+
+<p>
+Returns the code points (as integers) from all characters in <code>s</code>
+that start between byte position <code>i</code> and <code>j</code> (both included).
+The default for <code>i</code> is 1 and for <code>j</code> is <code>i</code>.
+It raises an error if it meets any invalid byte sequence.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-utf8.len"><code>utf8.len (s [, i [, j [, lax]]])</code></a></h3>
+
+
+<p>
+Returns the number of UTF-8 characters in string <code>s</code>
+that start between positions <code>i</code> and <code>j</code> (both inclusive).
+The default for <code>i</code> is 1 and for <code>j</code> is -1.
+If it finds any invalid byte sequence,
+returns <b>fail</b> plus the position of the first invalid byte.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-utf8.offset"><code>utf8.offset (s, n [, i])</code></a></h3>
+
+
+<p>
+Returns the position (in bytes) where the encoding of the
+<code>n</code>-th character of <code>s</code>
+(counting from position <code>i</code>) starts.
+A negative <code>n</code> gets characters before position <code>i</code>.
+The default for <code>i</code> is 1 when <code>n</code> is non-negative
+and <code>#s + 1</code> otherwise,
+so that <code>utf8.offset(s, -n)</code> gets the offset of the
+<code>n</code>-th character from the end of the string.
+If the specified character is neither in the subject
+nor right after its end,
+the function returns <b>fail</b>.
+
+
+<p>
+As a special case,
+when <code>n</code> is 0 the function returns the start of the encoding
+of the character that contains the <code>i</code>-th byte of <code>s</code>.
+
+
+<p>
+This function assumes that <code>s</code> is a valid UTF-8 string.
+
+
+
+
+
+
+
+<h2>6.6 &ndash; <a name="6.6">Table Manipulation</a></h2>
+
+<p>
+This library provides generic functions for table manipulation.
+It provides all its functions inside the table <a name="pdf-table"><code>table</code></a>.
+
+
+<p>
+Remember that, whenever an operation needs the length of a table,
+all caveats about the length operator apply (see <a href="#3.4.7">&sect;3.4.7</a>).
+All functions ignore non-numeric keys
+in the tables given as arguments.
+
+
+<p>
+<hr><h3><a name="pdf-table.concat"><code>table.concat (list [, sep [, i [, j]]])</code></a></h3>
+
+
+<p>
+Given a list where all elements are strings or numbers,
+returns the string <code>list[i]..sep..list[i+1] &middot;&middot;&middot; sep..list[j]</code>.
+The default value for <code>sep</code> is the empty string,
+the default for <code>i</code> is 1,
+and the default for <code>j</code> is <code>#list</code>.
+If <code>i</code> is greater than <code>j</code>, returns the empty string.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-table.insert"><code>table.insert (list, [pos,] value)</code></a></h3>
+
+
+<p>
+Inserts element <code>value</code> at position <code>pos</code> in <code>list</code>,
+shifting up the elements
+<code>list[pos], list[pos+1], &middot;&middot;&middot;, list[#list]</code>.
+The default value for <code>pos</code> is <code>#list+1</code>,
+so that a call <code>table.insert(t,x)</code> inserts <code>x</code> at the end
+of the list <code>t</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-table.move"><code>table.move (a1, f, e, t [,a2])</code></a></h3>
+
+
+<p>
+Moves elements from the table <code>a1</code> to the table <code>a2</code>,
+performing the equivalent to the following
+multiple assignment:
+<code>a2[t],&middot;&middot;&middot; = a1[f],&middot;&middot;&middot;,a1[e]</code>.
+The default for <code>a2</code> is <code>a1</code>.
+The destination range can overlap with the source range.
+The number of elements to be moved must fit in a Lua integer.
+
+
+<p>
+Returns the destination table <code>a2</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-table.pack"><code>table.pack (&middot;&middot;&middot;)</code></a></h3>
+
+
+<p>
+Returns a new table with all arguments stored into keys 1, 2, etc.
+and with a field "<code>n</code>" with the total number of arguments.
+Note that the resulting table may not be a sequence,
+if some arguments are <b>nil</b>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-table.remove"><code>table.remove (list [, pos])</code></a></h3>
+
+
+<p>
+Removes from <code>list</code> the element at position <code>pos</code>,
+returning the value of the removed element.
+When <code>pos</code> is an integer between 1 and <code>#list</code>,
+it shifts down the elements
+<code>list[pos+1], list[pos+2], &middot;&middot;&middot;, list[#list]</code>
+and erases element <code>list[#list]</code>;
+The index <code>pos</code> can also be 0 when <code>#list</code> is 0,
+or <code>#list + 1</code>.
+
+
+<p>
+The default value for <code>pos</code> is <code>#list</code>,
+so that a call <code>table.remove(l)</code> removes the last element
+of the list <code>l</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-table.sort"><code>table.sort (list [, comp])</code></a></h3>
+
+
+<p>
+Sorts the list elements in a given order, <em>in-place</em>,
+from <code>list[1]</code> to <code>list[#list]</code>.
+If <code>comp</code> is given,
+then it must be a function that receives two list elements
+and returns true when the first element must come
+before the second in the final order
+(so that, after the sort,
+<code>i &lt; j</code> implies <code>not comp(list[j],list[i])</code>).
+If <code>comp</code> is not given,
+then the standard Lua operator <code>&lt;</code> is used instead.
+
+
+<p>
+Note that the <code>comp</code> function must define
+a strict partial order over the elements in the list;
+that is, it must be asymmetric and transitive.
+Otherwise, no valid sort may be possible.
+
+
+<p>
+The sort algorithm is not stable:
+elements considered equal by the given order
+may have their relative positions changed by the sort.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-table.unpack"><code>table.unpack (list [, i [, j]])</code></a></h3>
+
+
+<p>
+Returns the elements from the given list.
+This function is equivalent to
+
+<pre>
+     return list[i], list[i+1], &middot;&middot;&middot;, list[j]
+</pre><p>
+By default, <code>i</code> is&nbsp;1 and <code>j</code> is <code>#list</code>.
+
+
+
+
+
+
+
+<h2>6.7 &ndash; <a name="6.7">Mathematical Functions</a></h2>
+
+<p>
+This library provides basic mathematical functions.
+It provides all its functions and constants inside the table <a name="pdf-math"><code>math</code></a>.
+Functions with the annotation "<code>integer/float</code>" give
+integer results for integer arguments
+and float results for non-integer arguments.
+The rounding functions
+<a href="#pdf-math.ceil"><code>math.ceil</code></a>, <a href="#pdf-math.floor"><code>math.floor</code></a>, and <a href="#pdf-math.modf"><code>math.modf</code></a>
+return an integer when the result fits in the range of an integer,
+or a float otherwise.
+
+
+<p>
+<hr><h3><a name="pdf-math.abs"><code>math.abs (x)</code></a></h3>
+
+
+<p>
+Returns the maximum value between <code>x</code> and <code>-x</code>. (integer/float)
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.acos"><code>math.acos (x)</code></a></h3>
+
+
+<p>
+Returns the arc cosine of <code>x</code> (in radians).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.asin"><code>math.asin (x)</code></a></h3>
+
+
+<p>
+Returns the arc sine of <code>x</code> (in radians).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.atan"><code>math.atan (y [, x])</code></a></h3>
+
+
+<p>
+
+Returns the arc tangent of <code>y/x</code> (in radians),
+but uses the signs of both arguments to find the
+quadrant of the result.
+It also handles correctly the case of <code>x</code> being zero.
+
+
+<p>
+The default value for <code>x</code> is 1,
+so that the call <code>math.atan(y)</code>
+returns the arc tangent of <code>y</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.ceil"><code>math.ceil (x)</code></a></h3>
+
+
+<p>
+Returns the smallest integral value greater than or equal to <code>x</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.cos"><code>math.cos (x)</code></a></h3>
+
+
+<p>
+Returns the cosine of <code>x</code> (assumed to be in radians).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.deg"><code>math.deg (x)</code></a></h3>
+
+
+<p>
+Converts the angle <code>x</code> from radians to degrees.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.exp"><code>math.exp (x)</code></a></h3>
+
+
+<p>
+Returns the value <em>e<sup>x</sup></em>
+(where <code>e</code> is the base of natural logarithms).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.floor"><code>math.floor (x)</code></a></h3>
+
+
+<p>
+Returns the largest integral value less than or equal to <code>x</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.fmod"><code>math.fmod (x, y)</code></a></h3>
+
+
+<p>
+Returns the remainder of the division of <code>x</code> by <code>y</code>
+that rounds the quotient towards zero. (integer/float)
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.huge"><code>math.huge</code></a></h3>
+
+
+<p>
+The float value <code>HUGE_VAL</code>,
+a value greater than any other numeric value.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.log"><code>math.log (x [, base])</code></a></h3>
+
+
+<p>
+Returns the logarithm of <code>x</code> in the given base.
+The default for <code>base</code> is <em>e</em>
+(so that the function returns the natural logarithm of <code>x</code>).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.max"><code>math.max (x, &middot;&middot;&middot;)</code></a></h3>
+
+
+<p>
+Returns the argument with the maximum value,
+according to the Lua operator <code>&lt;</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.maxinteger"><code>math.maxinteger</code></a></h3>
+An integer with the maximum value for an integer.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.min"><code>math.min (x, &middot;&middot;&middot;)</code></a></h3>
+
+
+<p>
+Returns the argument with the minimum value,
+according to the Lua operator <code>&lt;</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.mininteger"><code>math.mininteger</code></a></h3>
+An integer with the minimum value for an integer.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.modf"><code>math.modf (x)</code></a></h3>
+
+
+<p>
+Returns the integral part of <code>x</code> and the fractional part of <code>x</code>.
+Its second result is always a float.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.pi"><code>math.pi</code></a></h3>
+
+
+<p>
+The value of <em>&pi;</em>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.rad"><code>math.rad (x)</code></a></h3>
+
+
+<p>
+Converts the angle <code>x</code> from degrees to radians.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.random"><code>math.random ([m [, n]])</code></a></h3>
+
+
+<p>
+When called without arguments,
+returns a pseudo-random float with uniform distribution
+in the range  <em>[0,1)</em>.  
+When called with two integers <code>m</code> and <code>n</code>,
+<code>math.random</code> returns a pseudo-random integer
+with uniform distribution in the range <em>[m, n]</em>.
+The call <code>math.random(n)</code>, for a positive <code>n</code>,
+is equivalent to <code>math.random(1,n)</code>.
+The call <code>math.random(0)</code> produces an integer with
+all bits (pseudo)random.
+
+
+<p>
+This function uses the <code>xoshiro256**</code> algorithm to produce
+pseudo-random 64-bit integers,
+which are the results of calls with argument&nbsp;0.
+Other results (ranges and floats)
+are unbiased extracted from these integers.
+
+
+<p>
+Lua initializes its pseudo-random generator with the equivalent of
+a call to <a href="#pdf-math.randomseed"><code>math.randomseed</code></a> with no arguments,
+so that <code>math.random</code> should generate
+different sequences of results each time the program runs.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.randomseed"><code>math.randomseed ([x [, y]])</code></a></h3>
+
+
+<p>
+When called with at least one argument,
+the integer parameters <code>x</code> and <code>y</code> are
+joined into a 128-bit <em>seed</em> that
+is used to reinitialize the pseudo-random generator;
+equal seeds produce equal sequences of numbers.
+The default for <code>y</code> is zero.
+
+
+<p>
+When called with no arguments,
+Lua generates a seed with
+a weak attempt for randomness.
+
+
+<p>
+This function returns the two seed components
+that were effectively used,
+so that setting them again repeats the sequence.
+
+
+<p>
+To ensure a required level of randomness to the initial state
+(or contrarily, to have a deterministic sequence,
+for instance when debugging a program),
+you should call <a href="#pdf-math.randomseed"><code>math.randomseed</code></a> with explicit arguments.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.sin"><code>math.sin (x)</code></a></h3>
+
+
+<p>
+Returns the sine of <code>x</code> (assumed to be in radians).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.sqrt"><code>math.sqrt (x)</code></a></h3>
+
+
+<p>
+Returns the square root of <code>x</code>.
+(You can also use the expression <code>x^0.5</code> to compute this value.)
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.tan"><code>math.tan (x)</code></a></h3>
+
+
+<p>
+Returns the tangent of <code>x</code> (assumed to be in radians).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.tointeger"><code>math.tointeger (x)</code></a></h3>
+
+
+<p>
+If the value <code>x</code> is convertible to an integer,
+returns that integer.
+Otherwise, returns <b>fail</b>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.type"><code>math.type (x)</code></a></h3>
+
+
+<p>
+Returns "<code>integer</code>" if <code>x</code> is an integer,
+"<code>float</code>" if it is a float,
+or <b>fail</b> if <code>x</code> is not a number.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.ult"><code>math.ult (m, n)</code></a></h3>
+
+
+<p>
+Returns a boolean,
+true if and only if integer <code>m</code> is below integer <code>n</code> when
+they are compared as unsigned integers.
+
+
+
+
+
+
+
+<h2>6.8 &ndash; <a name="6.8">Input and Output Facilities</a></h2>
+
+<p>
+The I/O library provides two different styles for file manipulation.
+The first one uses implicit file handles;
+that is, there are operations to set a default input file and a
+default output file,
+and all input/output operations are done over these default files.
+The second style uses explicit file handles.
+
+
+<p>
+When using implicit file handles,
+all operations are supplied by table <a name="pdf-io"><code>io</code></a>.
+When using explicit file handles,
+the operation <a href="#pdf-io.open"><code>io.open</code></a> returns a file handle
+and then all operations are supplied as methods of the file handle.
+
+
+<p>
+The metatable for file handles provides metamethods
+for <code>__gc</code> and <code>__close</code> that try
+to close the file when called.
+
+
+<p>
+The table <code>io</code> also provides
+three predefined file handles with their usual meanings from C:
+<a name="pdf-io.stdin"><code>io.stdin</code></a>, <a name="pdf-io.stdout"><code>io.stdout</code></a>, and <a name="pdf-io.stderr"><code>io.stderr</code></a>.
+The I/O library never closes these files.
+
+
+<p>
+Unless otherwise stated,
+all I/O functions return <b>fail</b> on failure,
+plus an error message as a second result and
+a system-dependent error code as a third result,
+and some non-false value on success.
+On non-POSIX systems,
+the computation of the error message and error code
+in case of errors
+may be not thread safe,
+because they rely on the global C variable <code>errno</code>.
+
+
+<p>
+<hr><h3><a name="pdf-io.close"><code>io.close ([file])</code></a></h3>
+
+
+<p>
+Equivalent to <code>file:close()</code>.
+Without a <code>file</code>, closes the default output file.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-io.flush"><code>io.flush ()</code></a></h3>
+
+
+<p>
+Equivalent to <code>io.output():flush()</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-io.input"><code>io.input ([file])</code></a></h3>
+
+
+<p>
+When called with a file name, it opens the named file (in text mode),
+and sets its handle as the default input file.
+When called with a file handle,
+it simply sets this file handle as the default input file.
+When called without arguments,
+it returns the current default input file.
+
+
+<p>
+In case of errors this function raises the error,
+instead of returning an error code.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-io.lines"><code>io.lines ([filename, &middot;&middot;&middot;])</code></a></h3>
+
+
+<p>
+Opens the given file name in read mode
+and returns an iterator function that
+works like <code>file:lines(&middot;&middot;&middot;)</code> over the opened file.
+When the iterator function fails to read any value,
+it automatically closes the file.
+Besides the iterator function,
+<code>io.lines</code> returns three other values:
+two <b>nil</b> values as placeholders,
+plus the created file handle.
+Therefore, when used in a generic <b>for</b> loop,
+the file is closed also if the loop is interrupted by an
+error or a <b>break</b>.
+
+
+<p>
+The call <code>io.lines()</code> (with no file name) is equivalent
+to <code>io.input():lines("l")</code>;
+that is, it iterates over the lines of the default input file.
+In this case, the iterator does not close the file when the loop ends.
+
+
+<p>
+In case of errors opening the file,
+this function raises the error,
+instead of returning an error code.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-io.open"><code>io.open (filename [, mode])</code></a></h3>
+
+
+<p>
+This function opens a file,
+in the mode specified in the string <code>mode</code>.
+In case of success,
+it returns a new file handle.
+
+
+<p>
+The <code>mode</code> string can be any of the following:
+
+<ul>
+<li><b>"<code>r</code>": </b> read mode (the default);</li>
+<li><b>"<code>w</code>": </b> write mode;</li>
+<li><b>"<code>a</code>": </b> append mode;</li>
+<li><b>"<code>r+</code>": </b> update mode, all previous data is preserved;</li>
+<li><b>"<code>w+</code>": </b> update mode, all previous data is erased;</li>
+<li><b>"<code>a+</code>": </b> append update mode, previous data is preserved,
+  writing is only allowed at the end of file.</li>
+</ul><p>
+The <code>mode</code> string can also have a '<code>b</code>' at the end,
+which is needed in some systems to open the file in binary mode.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-io.output"><code>io.output ([file])</code></a></h3>
+
+
+<p>
+Similar to <a href="#pdf-io.input"><code>io.input</code></a>, but operates over the default output file.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-io.popen"><code>io.popen (prog [, mode])</code></a></h3>
+
+
+<p>
+This function is system dependent and is not available
+on all platforms.
+
+
+<p>
+Starts the program <code>prog</code> in a separated process and returns
+a file handle that you can use to read data from this program
+(if <code>mode</code> is <code>"r"</code>, the default)
+or to write data to this program
+(if <code>mode</code> is <code>"w"</code>).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-io.read"><code>io.read (&middot;&middot;&middot;)</code></a></h3>
+
+
+<p>
+Equivalent to <code>io.input():read(&middot;&middot;&middot;)</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-io.tmpfile"><code>io.tmpfile ()</code></a></h3>
+
+
+<p>
+In case of success,
+returns a handle for a temporary file.
+This file is opened in update mode
+and it is automatically removed when the program ends.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-io.type"><code>io.type (obj)</code></a></h3>
+
+
+<p>
+Checks whether <code>obj</code> is a valid file handle.
+Returns the string <code>"file"</code> if <code>obj</code> is an open file handle,
+<code>"closed file"</code> if <code>obj</code> is a closed file handle,
+or <b>fail</b> if <code>obj</code> is not a file handle.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-io.write"><code>io.write (&middot;&middot;&middot;)</code></a></h3>
+
+
+<p>
+Equivalent to <code>io.output():write(&middot;&middot;&middot;)</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-file:close"><code>file:close ()</code></a></h3>
+
+
+<p>
+Closes <code>file</code>.
+Note that files are automatically closed when
+their handles are garbage collected,
+but that takes an unpredictable amount of time to happen.
+
+
+<p>
+When closing a file handle created with <a href="#pdf-io.popen"><code>io.popen</code></a>,
+<a href="#pdf-file:close"><code>file:close</code></a> returns the same values
+returned by <a href="#pdf-os.execute"><code>os.execute</code></a>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-file:flush"><code>file:flush ()</code></a></h3>
+
+
+<p>
+Saves any written data to <code>file</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-file:lines"><code>file:lines (&middot;&middot;&middot;)</code></a></h3>
+
+
+<p>
+Returns an iterator function that,
+each time it is called,
+reads the file according to the given formats.
+When no format is given,
+uses "<code>l</code>" as a default.
+As an example, the construction
+
+<pre>
+     for c in file:lines(1) do <em>body</em> end
+</pre><p>
+will iterate over all characters of the file,
+starting at the current position.
+Unlike <a href="#pdf-io.lines"><code>io.lines</code></a>, this function does not close the file
+when the loop ends.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-file:read"><code>file:read (&middot;&middot;&middot;)</code></a></h3>
+
+
+<p>
+Reads the file <code>file</code>,
+according to the given formats, which specify what to read.
+For each format,
+the function returns a string or a number with the characters read,
+or <b>fail</b> if it cannot read data with the specified format.
+(In this latter case,
+the function does not read subsequent formats.)
+When called without arguments,
+it uses a default format that reads the next line
+(see below).
+
+
+<p>
+The available formats are
+
+<ul>
+
+<li><b>"<code>n</code>": </b>
+reads a numeral and returns it as a float or an integer,
+following the lexical conventions of Lua.
+(The numeral may have leading whitespaces and a sign.)
+This format always reads the longest input sequence that
+is a valid prefix for a numeral;
+if that prefix does not form a valid numeral
+(e.g., an empty string, "<code>0x</code>", or "<code>3.4e-</code>")
+or it is too long (more than 200 characters),
+it is discarded and the format returns <b>fail</b>.
+</li>
+
+<li><b>"<code>a</code>": </b>
+reads the whole file, starting at the current position.
+On end of file, it returns the empty string;
+this format never fails.
+</li>
+
+<li><b>"<code>l</code>": </b>
+reads the next line skipping the end of line,
+returning <b>fail</b> on end of file.
+This is the default format.
+</li>
+
+<li><b>"<code>L</code>": </b>
+reads the next line keeping the end-of-line character (if present),
+returning <b>fail</b> on end of file.
+</li>
+
+<li><b><em>number</em>: </b>
+reads a string with up to this number of bytes,
+returning <b>fail</b> on end of file.
+If <code>number</code> is zero,
+it reads nothing and returns an empty string,
+or <b>fail</b> on end of file.
+</li>
+
+</ul><p>
+The formats "<code>l</code>" and "<code>L</code>" should be used only for text files.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-file:seek"><code>file:seek ([whence [, offset]])</code></a></h3>
+
+
+<p>
+Sets and gets the file position,
+measured from the beginning of the file,
+to the position given by <code>offset</code> plus a base
+specified by the string <code>whence</code>, as follows:
+
+<ul>
+<li><b>"<code>set</code>": </b> base is position 0 (beginning of the file);</li>
+<li><b>"<code>cur</code>": </b> base is current position;</li>
+<li><b>"<code>end</code>": </b> base is end of file;</li>
+</ul><p>
+In case of success, <code>seek</code> returns the final file position,
+measured in bytes from the beginning of the file.
+If <code>seek</code> fails, it returns <b>fail</b>,
+plus a string describing the error.
+
+
+<p>
+The default value for <code>whence</code> is <code>"cur"</code>,
+and for <code>offset</code> is 0.
+Therefore, the call <code>file:seek()</code> returns the current
+file position, without changing it;
+the call <code>file:seek("set")</code> sets the position to the
+beginning of the file (and returns 0);
+and the call <code>file:seek("end")</code> sets the position to the
+end of the file, and returns its size.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-file:setvbuf"><code>file:setvbuf (mode [, size])</code></a></h3>
+
+
+<p>
+Sets the buffering mode for a file.
+There are three available modes:
+
+<ul>
+<li><b>"<code>no</code>": </b> no buffering.</li>
+<li><b>"<code>full</code>": </b> full buffering.</li>
+<li><b>"<code>line</code>": </b> line buffering.</li>
+</ul>
+
+<p>
+For the last two cases,
+<code>size</code> is a hint for the size of the buffer, in bytes.
+The default is an appropriate size.
+
+
+<p>
+The specific behavior of each mode is non portable;
+check the underlying ISO&nbsp;C function <code>setvbuf</code> in your platform for
+more details.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-file:write"><code>file:write (&middot;&middot;&middot;)</code></a></h3>
+
+
+<p>
+Writes the value of each of its arguments to <code>file</code>.
+The arguments must be strings or numbers.
+
+
+<p>
+In case of success, this function returns <code>file</code>.
+
+
+
+
+
+
+
+<h2>6.9 &ndash; <a name="6.9">Operating System Facilities</a></h2>
+
+<p>
+This library is implemented through table <a name="pdf-os"><code>os</code></a>.
+
+
+<p>
+<hr><h3><a name="pdf-os.clock"><code>os.clock ()</code></a></h3>
+
+
+<p>
+Returns an approximation of the amount in seconds of CPU time
+used by the program,
+as returned by the underlying ISO&nbsp;C function <code>clock</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-os.date"><code>os.date ([format [, time]])</code></a></h3>
+
+
+<p>
+Returns a string or a table containing date and time,
+formatted according to the given string <code>format</code>.
+
+
+<p>
+If the <code>time</code> argument is present,
+this is the time to be formatted
+(see the <a href="#pdf-os.time"><code>os.time</code></a> function for a description of this value).
+Otherwise, <code>date</code> formats the current time.
+
+
+<p>
+If <code>format</code> starts with '<code>!</code>',
+then the date is formatted in Coordinated Universal Time.
+After this optional character,
+if <code>format</code> is the string "<code>*t</code>",
+then <code>date</code> returns a table with the following fields:
+<code>year</code>, <code>month</code> (1&ndash;12), <code>day</code> (1&ndash;31),
+<code>hour</code> (0&ndash;23), <code>min</code> (0&ndash;59),
+<code>sec</code> (0&ndash;61, due to leap seconds),
+<code>wday</code> (weekday, 1&ndash;7, Sunday is&nbsp;1),
+<code>yday</code> (day of the year, 1&ndash;366),
+and <code>isdst</code> (daylight saving flag, a boolean).
+This last field may be absent
+if the information is not available.
+
+
+<p>
+If <code>format</code> is not "<code>*t</code>",
+then <code>date</code> returns the date as a string,
+formatted according to the same rules as the ISO&nbsp;C function <code>strftime</code>.
+
+
+<p>
+If <code>format</code> is absent, it defaults to "<code>%c</code>",
+which gives a human-readable date and time representation
+using the current locale.
+
+
+<p>
+On non-POSIX systems,
+this function may be not thread safe
+because of its reliance on C&nbsp;function <code>gmtime</code> and C&nbsp;function <code>localtime</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-os.difftime"><code>os.difftime (t2, t1)</code></a></h3>
+
+
+<p>
+Returns the difference, in seconds,
+from time <code>t1</code> to time <code>t2</code>
+(where the times are values returned by <a href="#pdf-os.time"><code>os.time</code></a>).
+In POSIX, Windows, and some other systems,
+this value is exactly <code>t2</code><em>-</em><code>t1</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-os.execute"><code>os.execute ([command])</code></a></h3>
+
+
+<p>
+This function is equivalent to the ISO&nbsp;C function <code>system</code>.
+It passes <code>command</code> to be executed by an operating system shell.
+Its first result is <b>true</b>
+if the command terminated successfully,
+or <b>fail</b> otherwise.
+After this first result
+the function returns a string plus a number,
+as follows:
+
+<ul>
+
+<li><b>"<code>exit</code>": </b>
+the command terminated normally;
+the following number is the exit status of the command.
+</li>
+
+<li><b>"<code>signal</code>": </b>
+the command was terminated by a signal;
+the following number is the signal that terminated the command.
+</li>
+
+</ul>
+
+<p>
+When called without a <code>command</code>,
+<code>os.execute</code> returns a boolean that is true if a shell is available.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-os.exit"><code>os.exit ([code [, close]])</code></a></h3>
+
+
+<p>
+Calls the ISO&nbsp;C function <code>exit</code> to terminate the host program.
+If <code>code</code> is <b>true</b>,
+the returned status is <code>EXIT_SUCCESS</code>;
+if <code>code</code> is <b>false</b>,
+the returned status is <code>EXIT_FAILURE</code>;
+if <code>code</code> is a number,
+the returned status is this number.
+The default value for <code>code</code> is <b>true</b>.
+
+
+<p>
+If the optional second argument <code>close</code> is true,
+closes the Lua state before exiting.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-os.getenv"><code>os.getenv (varname)</code></a></h3>
+
+
+<p>
+Returns the value of the process environment variable <code>varname</code>
+or <b>fail</b> if the variable is not defined.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-os.remove"><code>os.remove (filename)</code></a></h3>
+
+
+<p>
+Deletes the file (or empty directory, on POSIX systems)
+with the given name.
+If this function fails, it returns <b>fail</b>
+plus a string describing the error and the error code.
+Otherwise, it returns true.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-os.rename"><code>os.rename (oldname, newname)</code></a></h3>
+
+
+<p>
+Renames the file or directory named <code>oldname</code> to <code>newname</code>.
+If this function fails, it returns <b>fail</b>,
+plus a string describing the error and the error code.
+Otherwise, it returns true.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-os.setlocale"><code>os.setlocale (locale [, category])</code></a></h3>
+
+
+<p>
+Sets the current locale of the program.
+<code>locale</code> is a system-dependent string specifying a locale;
+<code>category</code> is an optional string describing which category to change:
+<code>"all"</code>, <code>"collate"</code>, <code>"ctype"</code>,
+<code>"monetary"</code>, <code>"numeric"</code>, or <code>"time"</code>;
+the default category is <code>"all"</code>.
+The function returns the name of the new locale,
+or <b>fail</b> if the request cannot be honored.
+
+
+<p>
+If <code>locale</code> is the empty string,
+the current locale is set to an implementation-defined native locale.
+If <code>locale</code> is the string "<code>C</code>",
+the current locale is set to the standard C locale.
+
+
+<p>
+When called with <b>nil</b> as the first argument,
+this function only returns the name of the current locale
+for the given category.
+
+
+<p>
+This function may be not thread safe
+because of its reliance on C&nbsp;function <code>setlocale</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-os.time"><code>os.time ([table])</code></a></h3>
+
+
+<p>
+Returns the current time when called without arguments,
+or a time representing the local date and time specified by the given table.
+This table must have fields <code>year</code>, <code>month</code>, and <code>day</code>,
+and may have fields
+<code>hour</code> (default is 12),
+<code>min</code> (default is 0),
+<code>sec</code> (default is 0),
+and <code>isdst</code> (default is <b>nil</b>).
+Other fields are ignored.
+For a description of these fields, see the <a href="#pdf-os.date"><code>os.date</code></a> function.
+
+
+<p>
+When the function is called,
+the values in these fields do not need to be inside their valid ranges.
+For instance, if <code>sec</code> is -10,
+it means 10 seconds before the time specified by the other fields;
+if <code>hour</code> is 1000,
+it means 1000 hours after the time specified by the other fields.
+
+
+<p>
+The returned value is a number, whose meaning depends on your system.
+In POSIX, Windows, and some other systems,
+this number counts the number
+of seconds since some given start time (the "epoch").
+In other systems, the meaning is not specified,
+and the number returned by <code>time</code> can be used only as an argument to
+<a href="#pdf-os.date"><code>os.date</code></a> and <a href="#pdf-os.difftime"><code>os.difftime</code></a>.
+
+
+<p>
+When called with a table,
+<code>os.time</code> also normalizes all the fields
+documented in the <a href="#pdf-os.date"><code>os.date</code></a> function,
+so that they represent the same time as before the call
+but with values inside their valid ranges.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-os.tmpname"><code>os.tmpname ()</code></a></h3>
+
+
+<p>
+Returns a string with a file name that can
+be used for a temporary file.
+The file must be explicitly opened before its use
+and explicitly removed when no longer needed.
+
+
+<p>
+In POSIX systems,
+this function also creates a file with that name,
+to avoid security risks.
+(Someone else might create the file with wrong permissions
+in the time between getting the name and creating the file.)
+You still have to open the file to use it
+and to remove it (even if you do not use it).
+
+
+<p>
+When possible,
+you may prefer to use <a href="#pdf-io.tmpfile"><code>io.tmpfile</code></a>,
+which automatically removes the file when the program ends.
+
+
+
+
+
+
+
+<h2>6.10 &ndash; <a name="6.10">The Debug Library</a></h2>
+
+<p>
+This library provides
+the functionality of the debug interface (<a href="#4.7">&sect;4.7</a>) to Lua programs.
+You should exert care when using this library.
+Several of its functions
+violate basic assumptions about Lua code
+(e.g., that variables local to a function
+cannot be accessed from outside;
+that userdata metatables cannot be changed by Lua code;
+that Lua programs do not crash)
+and therefore can compromise otherwise secure code.
+Moreover, some functions in this library may be slow.
+
+
+<p>
+All functions in this library are provided
+inside the <a name="pdf-debug"><code>debug</code></a> table.
+All functions that operate over a thread
+have an optional first argument which is the
+thread to operate over.
+The default is always the current thread.
+
+
+<p>
+<hr><h3><a name="pdf-debug.debug"><code>debug.debug ()</code></a></h3>
+
+
+<p>
+Enters an interactive mode with the user,
+running each string that the user enters.
+Using simple commands and other debug facilities,
+the user can inspect global and local variables,
+change their values, evaluate expressions, and so on.
+A line containing only the word <code>cont</code> finishes this function,
+so that the caller continues its execution.
+
+
+<p>
+Note that commands for <code>debug.debug</code> are not lexically nested
+within any function and so have no direct access to local variables.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-debug.gethook"><code>debug.gethook ([thread])</code></a></h3>
+
+
+<p>
+Returns the current hook settings of the thread, as three values:
+the current hook function, the current hook mask,
+and the current hook count,
+as set by the <a href="#pdf-debug.sethook"><code>debug.sethook</code></a> function.
+
+
+<p>
+Returns <b>fail</b> if there is no active hook.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-debug.getinfo"><code>debug.getinfo ([thread,] f [, what])</code></a></h3>
+
+
+<p>
+Returns a table with information about a function.
+You can give the function directly
+or you can give a number as the value of <code>f</code>,
+which means the function running at level <code>f</code> of the call stack
+of the given thread:
+level&nbsp;0 is the current function (<code>getinfo</code> itself);
+level&nbsp;1 is the function that called <code>getinfo</code>
+(except for tail calls, which do not count on the stack);
+and so on.
+If <code>f</code> is a number greater than the number of active functions,
+then <code>getinfo</code> returns <b>fail</b>.
+
+
+<p>
+The returned table can contain all the fields returned by <a href="#lua_getinfo"><code>lua_getinfo</code></a>,
+with the string <code>what</code> describing which fields to fill in.
+The default for <code>what</code> is to get all information available,
+except the table of valid lines.
+If present,
+the option '<code>f</code>'
+adds a field named <code>func</code> with the function itself.
+If present,
+the option '<code>L</code>'
+adds a field named <code>activelines</code> with the table of
+valid lines.
+
+
+<p>
+For instance, the expression <code>debug.getinfo(1,"n").name</code> returns
+a name for the current function,
+if a reasonable name can be found,
+and the expression <code>debug.getinfo(print)</code>
+returns a table with all available information
+about the <a href="#pdf-print"><code>print</code></a> function.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-debug.getlocal"><code>debug.getlocal ([thread,] f, local)</code></a></h3>
+
+
+<p>
+This function returns the name and the value of the local variable
+with index <code>local</code> of the function at level <code>f</code> of the stack.
+This function accesses not only explicit local variables,
+but also parameters and temporary values.
+
+
+<p>
+The first parameter or local variable has index&nbsp;1, and so on,
+following the order that they are declared in the code,
+counting only the variables that are active
+in the current scope of the function.
+Compile-time constants may not appear in this listing,
+if they were optimized away by the compiler.
+Negative indices refer to vararg arguments;
+-1 is the first vararg argument.
+The function returns <b>fail</b>
+if there is no variable with the given index,
+and raises an error when called with a level out of range.
+(You can call <a href="#pdf-debug.getinfo"><code>debug.getinfo</code></a> to check whether the level is valid.)
+
+
+<p>
+Variable names starting with '<code>(</code>' (open parenthesis) 
+represent variables with no known names
+(internal variables such as loop control variables,
+and variables from chunks saved without debug information).
+
+
+<p>
+The parameter <code>f</code> may also be a function.
+In that case, <code>getlocal</code> returns only the name of function parameters.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-debug.getmetatable"><code>debug.getmetatable (value)</code></a></h3>
+
+
+<p>
+Returns the metatable of the given <code>value</code>
+or <b>nil</b> if it does not have a metatable.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-debug.getregistry"><code>debug.getregistry ()</code></a></h3>
+
+
+<p>
+Returns the registry table (see <a href="#4.3">&sect;4.3</a>).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-debug.getupvalue"><code>debug.getupvalue (f, up)</code></a></h3>
+
+
+<p>
+This function returns the name and the value of the upvalue
+with index <code>up</code> of the function <code>f</code>.
+The function returns <b>fail</b>
+if there is no upvalue with the given index.
+
+
+<p>
+(For Lua functions,
+upvalues are the external local variables that the function uses,
+and that are consequently included in its closure.)
+
+
+<p>
+For C&nbsp;functions, this function uses the empty string <code>""</code>
+as a name for all upvalues.
+
+
+<p>
+Variable name '<code>?</code>' (interrogation mark)
+represents variables with no known names
+(variables from chunks saved without debug information).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-debug.getuservalue"><code>debug.getuservalue (u, n)</code></a></h3>
+
+
+<p>
+Returns the <code>n</code>-th user value associated
+to the userdata <code>u</code> plus a boolean,
+<b>false</b> if the userdata does not have that value.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-debug.setcstacklimit"><code>debug.setcstacklimit (limit)</code></a></h3>
+
+
+<p>
+Sets a new limit for the C stack.
+This limit controls how deeply nested calls can go in Lua,
+with the intent of avoiding a stack overflow.
+A limit too small restricts recursive calls pointlessly;
+a limit too large exposes the interpreter to stack-overflow crashes.
+Unfortunately, there is no way to know a priori
+the maximum safe limit for a platform.
+
+
+<p>
+Each call made from Lua code counts one unit.
+Other operations (e.g., calls made from C to Lua or resuming a coroutine)
+may have a higher cost.
+
+
+<p>
+This function has the following restrictions:
+
+<ul>
+<li>It can only be called from the main coroutine (thread);</li>
+<li>It cannot be called while handling a stack-overflow error;</li>
+<li><code>limit</code> must be less than 40000;</li>
+<li><code>limit</code> cannot be less than the amount of C stack in use.</li>
+</ul><p>
+If a call does not respect some restriction,
+it returns a false value.
+Otherwise,
+the call returns the old limit.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-debug.sethook"><code>debug.sethook ([thread,] hook, mask [, count])</code></a></h3>
+
+
+<p>
+Sets the given function as the debug hook.
+The string <code>mask</code> and the number <code>count</code> describe
+when the hook will be called.
+The string mask may have any combination of the following characters,
+with the given meaning:
+
+<ul>
+<li><b>'<code>c</code>': </b> the hook is called every time Lua calls a function;</li>
+<li><b>'<code>r</code>': </b> the hook is called every time Lua returns from a function;</li>
+<li><b>'<code>l</code>': </b> the hook is called every time Lua enters a new line of code.</li>
+</ul><p>
+Moreover,
+with a <code>count</code> different from zero,
+the hook is called also after every <code>count</code> instructions.
+
+
+<p>
+When called without arguments,
+<a href="#pdf-debug.sethook"><code>debug.sethook</code></a> turns off the hook.
+
+
+<p>
+When the hook is called, its first parameter is a string
+describing the event that has triggered its call:
+<code>"call"</code>, <code>"tail call"</code>, <code>"return"</code>,
+<code>"line"</code>, and <code>"count"</code>.
+For line events,
+the hook also gets the new line number as its second parameter.
+Inside a hook,
+you can call <code>getinfo</code> with level&nbsp;2 to get more information about
+the running function.
+(Level&nbsp;0 is the <code>getinfo</code> function,
+and level&nbsp;1 is the hook function.)
+
+
+
+
+<p>
+<hr><h3><a name="pdf-debug.setlocal"><code>debug.setlocal ([thread,] level, local, value)</code></a></h3>
+
+
+<p>
+This function assigns the value <code>value</code> to the local variable
+with index <code>local</code> of the function at level <code>level</code> of the stack.
+The function returns <b>fail</b> if there is no local
+variable with the given index,
+and raises an error when called with a <code>level</code> out of range.
+(You can call <code>getinfo</code> to check whether the level is valid.)
+Otherwise, it returns the name of the local variable.
+
+
+<p>
+See <a href="#pdf-debug.getlocal"><code>debug.getlocal</code></a> for more information about
+variable indices and names.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-debug.setmetatable"><code>debug.setmetatable (value, table)</code></a></h3>
+
+
+<p>
+Sets the metatable for the given <code>value</code> to the given <code>table</code>
+(which can be <b>nil</b>).
+Returns <code>value</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-debug.setupvalue"><code>debug.setupvalue (f, up, value)</code></a></h3>
+
+
+<p>
+This function assigns the value <code>value</code> to the upvalue
+with index <code>up</code> of the function <code>f</code>.
+The function returns <b>fail</b> if there is no upvalue
+with the given index.
+Otherwise, it returns the name of the upvalue.
+
+
+<p>
+See <a href="#pdf-debug.getupvalue"><code>debug.getupvalue</code></a> for more information about upvalues.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-debug.setuservalue"><code>debug.setuservalue (udata, value, n)</code></a></h3>
+
+
+<p>
+Sets the given <code>value</code> as
+the <code>n</code>-th user value associated to the given <code>udata</code>.
+<code>udata</code> must be a full userdata.
+
+
+<p>
+Returns <code>udata</code>,
+or <b>fail</b> if the userdata does not have that value.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-debug.traceback"><code>debug.traceback ([thread,] [message [, level]])</code></a></h3>
+
+
+<p>
+If <code>message</code> is present but is neither a string nor <b>nil</b>,
+this function returns <code>message</code> without further processing.
+Otherwise,
+it returns a string with a traceback of the call stack.
+The optional <code>message</code> string is appended
+at the beginning of the traceback.
+An optional <code>level</code> number tells at which level
+to start the traceback
+(default is 1, the function calling <code>traceback</code>).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-debug.upvalueid"><code>debug.upvalueid (f, n)</code></a></h3>
+
+
+<p>
+Returns a unique identifier (as a light userdata)
+for the upvalue numbered <code>n</code>
+from the given function.
+
+
+<p>
+These unique identifiers allow a program to check whether different
+closures share upvalues.
+Lua closures that share an upvalue
+(that is, that access a same external local variable)
+will return identical ids for those upvalue indices.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-debug.upvaluejoin"><code>debug.upvaluejoin (f1, n1, f2, n2)</code></a></h3>
+
+
+<p>
+Make the <code>n1</code>-th upvalue of the Lua closure <code>f1</code>
+refer to the <code>n2</code>-th upvalue of the Lua closure <code>f2</code>.
+
+
+
+
+
+
+
+<h1>7 &ndash; <a name="7">Lua Standalone</a></h1>
+
+<p>
+Although Lua has been designed as an extension language,
+to be embedded in a host C&nbsp;program,
+it is also frequently used as a standalone language.
+An interpreter for Lua as a standalone language,
+called simply <code>lua</code>,
+is provided with the standard distribution.
+The standalone interpreter includes
+all standard libraries.
+Its usage is:
+
+<pre>
+     lua [options] [script [args]]
+</pre><p>
+The options are:
+
+<ul>
+<li><b><code>-e <em>stat</em></code>: </b> execute string <em>stat</em>;</li>
+<li><b><code>-i</code>: </b> enter interactive mode after running <em>script</em>;</li>
+<li><b><code>-l <em>mod</em></code>: </b> "require" <em>mod</em> and assign the
+  result to global <em>mod</em>;</li>
+<li><b><code>-v</code>: </b> print version information;</li>
+<li><b><code>-E</code>: </b> ignore environment variables;</li>
+<li><b><code>-W</code>: </b> turn warnings on;</li>
+<li><b><code>--</code>: </b> stop handling options;</li>
+<li><b><code>-</code>: </b> execute <code>stdin</code> as a file and stop handling options.</li>
+</ul><p>
+After handling its options, <code>lua</code> runs the given <em>script</em>.
+When called without arguments,
+<code>lua</code> behaves as <code>lua -v -i</code>
+when the standard input (<code>stdin</code>) is a terminal,
+and as <code>lua -</code> otherwise.
+
+
+<p>
+When called without the option <code>-E</code>,
+the interpreter checks for an environment variable <a name="pdf-LUA_INIT_5_4"><code>LUA_INIT_5_4</code></a>
+(or <a name="pdf-LUA_INIT"><code>LUA_INIT</code></a> if the versioned name is not defined)
+before running any argument.
+If the variable content has the format <code>@<em>filename</em></code>,
+then <code>lua</code> executes the file.
+Otherwise, <code>lua</code> executes the string itself.
+
+
+<p>
+When called with the option <code>-E</code>,
+Lua does not consult any environment variables.
+In particular,
+the values of <a href="#pdf-package.path"><code>package.path</code></a> and <a href="#pdf-package.cpath"><code>package.cpath</code></a>
+are set with the default paths defined in <code>luaconf.h</code>.
+
+
+<p>
+The options <code>-e</code>, <code>-l</code>, and <code>-W</code> are handled in
+the order they appear.
+For instance, an invocation like
+
+<pre>
+     $ lua -e 'a=1' -llib1 script.lua
+</pre><p>
+will first set <code>a</code> to 1, then require the library <code>lib1</code>,
+and finally run the file <code>script.lua</code> with no arguments.
+(Here <code>$</code> is the shell prompt. Your prompt may be different.)
+
+
+<p>
+Before running any code,
+<code>lua</code> collects all command-line arguments
+in a global table called <code>arg</code>.
+The script name goes to index 0,
+the first argument after the script name goes to index 1,
+and so on.
+Any arguments before the script name
+(that is, the interpreter name plus its options)
+go to negative indices.
+For instance, in the call
+
+<pre>
+     $ lua -la b.lua t1 t2
+</pre><p>
+the table is like this:
+
+<pre>
+     arg = { [-2] = "lua", [-1] = "-la",
+             [0] = "b.lua",
+             [1] = "t1", [2] = "t2" }
+</pre><p>
+If there is no script in the call,
+the interpreter name goes to index 0,
+followed by the other arguments.
+For instance, the call
+
+<pre>
+     $ lua -e "print(arg[1])"
+</pre><p>
+will print "<code>-e</code>".
+If there is a script,
+the script is called with arguments
+<code>arg[1]</code>, &middot;&middot;&middot;, <code>arg[#arg]</code>.
+Like all chunks in Lua,
+the script is compiled as a vararg function.
+
+
+<p>
+In interactive mode,
+Lua repeatedly prompts and waits for a line.
+After reading a line,
+Lua first try to interpret the line as an expression.
+If it succeeds, it prints its value.
+Otherwise, it interprets the line as a statement.
+If you write an incomplete statement,
+the interpreter waits for its completion
+by issuing a different prompt.
+
+
+<p>
+If the global variable <a name="pdf-_PROMPT"><code>_PROMPT</code></a> contains a string,
+then its value is used as the prompt.
+Similarly, if the global variable <a name="pdf-_PROMPT2"><code>_PROMPT2</code></a> contains a string,
+its value is used as the secondary prompt
+(issued during incomplete statements).
+
+
+<p>
+In case of unprotected errors in the script,
+the interpreter reports the error to the standard error stream.
+If the error object is not a string but
+has a metamethod <code>__tostring</code>,
+the interpreter calls this metamethod to produce the final message.
+Otherwise, the interpreter converts the error object to a string
+and adds a stack traceback to it.
+When warnings are on,
+they are simply printed in the standard error output.
+
+
+<p>
+When finishing normally,
+the interpreter closes its main Lua state
+(see <a href="#lua_close"><code>lua_close</code></a>).
+The script can avoid this step by
+calling <a href="#pdf-os.exit"><code>os.exit</code></a> to terminate.
+
+
+<p>
+To allow the use of Lua as a
+script interpreter in Unix systems,
+Lua skips the first line of a file chunk if it starts with <code>#</code>.
+Therefore, Lua scripts can be made into executable programs
+by using <code>chmod +x</code> and the&nbsp;<code>#!</code> form,
+as in
+
+<pre>
+     #!/usr/local/bin/lua
+</pre><p>
+Of course,
+the location of the Lua interpreter may be different in your machine.
+If <code>lua</code> is in your <code>PATH</code>,
+then
+
+<pre>
+     #!/usr/bin/env lua
+</pre><p>
+is a more portable solution.
+
+
+
+<h1>8 &ndash; <a name="8">Incompatibilities with the Previous Version</a></h1>
+
+
+
+<p>
+Here we list the incompatibilities that you may find when moving a program
+from Lua&nbsp;5.3 to Lua&nbsp;5.4.
+
+
+<p>
+You can avoid some incompatibilities by compiling Lua with
+appropriate options (see file <code>luaconf.h</code>).
+However,
+all these compatibility options will be removed in the future.
+More often than not,
+compatibility issues arise when these compatibility options
+are removed.
+So, whenever you have the chance,
+you should try to test your code with a version of Lua compiled
+with all compatibility options turned off.
+That will ease transitions to newer versions of Lua.
+
+
+<p>
+Lua versions can always change the C API in ways that
+do not imply source-code changes in a program,
+such as the numeric values for constants
+or the implementation of functions as macros.
+Therefore,
+you should never assume that binaries are compatible between
+different Lua versions.
+Always recompile clients of the Lua API when
+using a new version.
+
+
+<p>
+Similarly, Lua versions can always change the internal representation
+of precompiled chunks;
+precompiled chunks are not compatible between different Lua versions.
+
+
+<p>
+The standard paths in the official distribution may
+change between versions.
+
+
+
+
+
+<h2>8.1 &ndash; <a name="8.1">Incompatibilities in the Language</a></h2>
+<ul>
+
+<li>
+The coercion of strings to numbers in
+arithmetic and bitwise operations
+has been removed from the core language.
+The string library does a similar job
+for arithmetic (but not for bitwise) operations
+using the string metamethods.
+However, unlike in previous versions,
+the new implementation preserves the implicit type of the numeral
+in the string.
+For instance, the result of <code>"1" + "2"</code> now is an integer,
+not a float.
+</li>
+
+<li>
+Literal decimal integer constants that overflow are read as floats,
+instead of wrapping around.
+You can use hexadecimal notation for such constants if you
+want the old behavior
+(reading them as integers with wrap around).
+</li>
+
+<li>
+The use of the <code>__lt</code> metamethod to emulate <code>__le</code>
+has been removed.
+When needed, this metamethod must be explicitly defined.
+</li>
+
+<li>
+The semantics of the numerical <b>for</b> loop
+over integers changed in some details.
+In particular, the control variable never wraps around.
+</li>
+
+<li>
+A label for a <b>goto</b> cannot be declared where a label with the same
+name is visible, even if this other label is declared in an enclosing
+block.
+</li>
+
+<li>
+When finalizing an object,
+Lua does not ignore <code>__gc</code> metamethods that are not functions.
+Any value will be called, if present.
+(Non-callable values will generate a warning,
+like any other error when calling a finalizer.)
+</li>
+
+</ul>
+
+
+
+
+<h2>8.2 &ndash; <a name="8.2">Incompatibilities in the Libraries</a></h2>
+<ul>
+
+<li>
+The function <a href="#pdf-print"><code>print</code></a> does not call <a href="#pdf-tostring"><code>tostring</code></a>
+to format its arguments;
+instead, it has this functionality hardwired.
+You should use <code>__tostring</code> to modify how values are printed.
+</li>
+
+<li>
+The pseudo-random number generator used by the function <a href="#pdf-math.random"><code>math.random</code></a>
+now starts with a somewhat random seed.
+Moreover, it uses a different algorithm.
+</li>
+
+<li>
+By default, the decoding functions in the <a href="#pdf-utf8"><code>utf8</code></a> library
+do not accept surrogates as valid code points.
+An extra parameter in these functions makes them more permissive.
+</li>
+
+<li>
+The options "<code>setpause</code>" and "<code>setstepmul</code>"
+of the function <a href="#pdf-collectgarbage"><code>collectgarbage</code></a> are deprecated.
+You should use the new option "<code>incremental</code>" to set them.
+</li>
+
+<li>
+The function <a href="#pdf-io.lines"><code>io.lines</code></a> now returns four values,
+instead of just one.
+That can be a problem when it is used as the sole
+argument to another function that has optional parameters,
+such as in <code>load(io.lines(filename, "L"))</code>.
+To fix that issue,
+you can wrap the call into parentheses,
+to adjust its number of results to one.
+</li>
+
+</ul>
+
+
+
+
+<h2>8.3 &ndash; <a name="8.3">Incompatibilities in the API</a></h2>
+
+
+<ul>
+
+<li>
+Full userdata now has an arbitrary number of associated user values.
+Therefore, the functions <code>lua_newuserdata</code>,
+<code>lua_setuservalue</code>, and <code>lua_getuservalue</code> were
+replaced by <a href="#lua_newuserdatauv"><code>lua_newuserdatauv</code></a>,
+<a href="#lua_setiuservalue"><code>lua_setiuservalue</code></a>, and <a href="#lua_getiuservalue"><code>lua_getiuservalue</code></a>,
+which have an extra argument.
+
+
+<p>
+For compatibility, the old names still work as macros assuming
+one single user value.
+Note, however, that userdata with zero user values
+are more efficient memory-wise.
+</li>
+
+<li>
+The function <a href="#lua_resume"><code>lua_resume</code></a> has an extra parameter.
+This out parameter returns the number of values on
+the top of the stack that were yielded or returned by the coroutine.
+(In previous versions,
+those values were the entire stack.)
+</li>
+
+<li>
+The function <a href="#lua_version"><code>lua_version</code></a> returns the version number,
+instead of an address of the version number.
+The Lua core should work correctly with libraries using their
+own static copies of the same core,
+so there is no need to check whether they are using the same
+address space.
+</li>
+
+<li>
+The constant <code>LUA_ERRGCMM</code> was removed.
+Errors in finalizers are never propagated;
+instead, they generate a warning.
+</li>
+
+<li>
+The options <code>LUA_GCSETPAUSE</code> and <code>LUA_GCSETSTEPMUL</code>
+of the function <a href="#lua_gc"><code>lua_gc</code></a> are deprecated.
+You should use the new option <code>LUA_GCINC</code> to set them.
+</li>
+
+</ul>
+
+
+
+
+<h1>9 &ndash; <a name="9">The Complete Syntax of Lua</a></h1>
+
+<p>
+Here is the complete syntax of Lua in extended BNF.
+As usual in extended BNF,
+{A} means 0 or more As,
+and [A] means an optional A.
+(For operator precedences, see <a href="#3.4.8">&sect;3.4.8</a>;
+for a description of the terminals
+Name, Numeral,
+and LiteralString, see <a href="#3.1">&sect;3.1</a>.)
+
+
+
+
+<pre>
+
+	chunk ::= block
+
+	block ::= {stat} [retstat]
+
+	stat ::=  &lsquo;<b>;</b>&rsquo; | 
+		 varlist &lsquo;<b>=</b>&rsquo; explist | 
+		 functioncall | 
+		 label | 
+		 <b>break</b> | 
+		 <b>goto</b> Name | 
+		 <b>do</b> block <b>end</b> | 
+		 <b>while</b> exp <b>do</b> block <b>end</b> | 
+		 <b>repeat</b> block <b>until</b> exp | 
+		 <b>if</b> exp <b>then</b> block {<b>elseif</b> exp <b>then</b> block} [<b>else</b> block] <b>end</b> | 
+		 <b>for</b> Name &lsquo;<b>=</b>&rsquo; exp &lsquo;<b>,</b>&rsquo; exp [&lsquo;<b>,</b>&rsquo; exp] <b>do</b> block <b>end</b> | 
+		 <b>for</b> namelist <b>in</b> explist <b>do</b> block <b>end</b> | 
+		 <b>function</b> funcname funcbody | 
+		 <b>local</b> <b>function</b> Name funcbody | 
+		 <b>local</b> attnamelist [&lsquo;<b>=</b>&rsquo; explist] 
+
+	attnamelist ::=  Name attrib {&lsquo;<b>,</b>&rsquo; Name attrib}
+
+	attrib ::= [&lsquo;<b>&lt;</b>&rsquo; Name &lsquo;<b>&gt;</b>&rsquo;]
+
+	retstat ::= <b>return</b> [explist] [&lsquo;<b>;</b>&rsquo;]
+
+	label ::= &lsquo;<b>::</b>&rsquo; Name &lsquo;<b>::</b>&rsquo;
+
+	funcname ::= Name {&lsquo;<b>.</b>&rsquo; Name} [&lsquo;<b>:</b>&rsquo; Name]
+
+	varlist ::= var {&lsquo;<b>,</b>&rsquo; var}
+
+	var ::=  Name | prefixexp &lsquo;<b>[</b>&rsquo; exp &lsquo;<b>]</b>&rsquo; | prefixexp &lsquo;<b>.</b>&rsquo; Name 
+
+	namelist ::= Name {&lsquo;<b>,</b>&rsquo; Name}
+
+	explist ::= exp {&lsquo;<b>,</b>&rsquo; exp}
+
+	exp ::=  <b>nil</b> | <b>false</b> | <b>true</b> | Numeral | LiteralString | &lsquo;<b>...</b>&rsquo; | functiondef | 
+		 prefixexp | tableconstructor | exp binop exp | unop exp 
+
+	prefixexp ::= var | functioncall | &lsquo;<b>(</b>&rsquo; exp &lsquo;<b>)</b>&rsquo;
+
+	functioncall ::=  prefixexp args | prefixexp &lsquo;<b>:</b>&rsquo; Name args 
+
+	args ::=  &lsquo;<b>(</b>&rsquo; [explist] &lsquo;<b>)</b>&rsquo; | tableconstructor | LiteralString 
+
+	functiondef ::= <b>function</b> funcbody
+
+	funcbody ::= &lsquo;<b>(</b>&rsquo; [parlist] &lsquo;<b>)</b>&rsquo; block <b>end</b>
+
+	parlist ::= namelist [&lsquo;<b>,</b>&rsquo; &lsquo;<b>...</b>&rsquo;] | &lsquo;<b>...</b>&rsquo;
+
+	tableconstructor ::= &lsquo;<b>{</b>&rsquo; [fieldlist] &lsquo;<b>}</b>&rsquo;
+
+	fieldlist ::= field {fieldsep field} [fieldsep]
+
+	field ::= &lsquo;<b>[</b>&rsquo; exp &lsquo;<b>]</b>&rsquo; &lsquo;<b>=</b>&rsquo; exp | Name &lsquo;<b>=</b>&rsquo; exp | exp
+
+	fieldsep ::= &lsquo;<b>,</b>&rsquo; | &lsquo;<b>;</b>&rsquo;
+
+	binop ::=  &lsquo;<b>+</b>&rsquo; | &lsquo;<b>-</b>&rsquo; | &lsquo;<b>*</b>&rsquo; | &lsquo;<b>/</b>&rsquo; | &lsquo;<b>//</b>&rsquo; | &lsquo;<b>^</b>&rsquo; | &lsquo;<b>%</b>&rsquo; | 
+		 &lsquo;<b>&amp;</b>&rsquo; | &lsquo;<b>~</b>&rsquo; | &lsquo;<b>|</b>&rsquo; | &lsquo;<b>&gt;&gt;</b>&rsquo; | &lsquo;<b>&lt;&lt;</b>&rsquo; | &lsquo;<b>..</b>&rsquo; | 
+		 &lsquo;<b>&lt;</b>&rsquo; | &lsquo;<b>&lt;=</b>&rsquo; | &lsquo;<b>&gt;</b>&rsquo; | &lsquo;<b>&gt;=</b>&rsquo; | &lsquo;<b>==</b>&rsquo; | &lsquo;<b>~=</b>&rsquo; | 
+		 <b>and</b> | <b>or</b>
+
+	unop ::= &lsquo;<b>-</b>&rsquo; | <b>not</b> | &lsquo;<b>#</b>&rsquo; | &lsquo;<b>~</b>&rsquo;
+
+</pre>
+
+<p>
+
+
+
+
+
+
+
+<P CLASS="footer">
+Last update:
+Thu Jun 18 16:10:16 UTC 2020
+</P>
+<!--
+Last change: revised for Lua 5.4.0 (final)
+-->
+
+</body></html>
+
diff --git a/test/external/lua-5.4.0/doc/osi-certified-72x60.png b/test/external/lua-5.4.0/doc/osi-certified-72x60.png
new file mode 100644
index 0000000..07df5f6
--- /dev/null
+++ b/test/external/lua-5.4.0/doc/osi-certified-72x60.png
diff --git a/test/external/lua-5.4.0/doc/readme.html b/test/external/lua-5.4.0/doc/readme.html
new file mode 100644
index 0000000..eebd340
--- /dev/null
+++ b/test/external/lua-5.4.0/doc/readme.html
@@ -0,0 +1,340 @@
+<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
+<HTML>
+<HEAD>
+<TITLE>Lua 5.4 readme</TITLE>
+<LINK REL="stylesheet" TYPE="text/css" HREF="lua.css">
+<META HTTP-EQUIV="content-type" CONTENT="text/html; charset=iso-8859-1">
+<STYLE TYPE="text/css">
+blockquote, .display {
+	border: solid #a0a0a0 2px ;
+	border-radius: 8px ;
+	padding: 1em ;
+	margin: 0px ;
+}
+
+.display {
+	word-spacing: 0.25em ;
+}
+
+dl.display dd {
+	padding-bottom: 0.2em ;
+}
+
+tt, kbd, code {
+	font-size: 12pt ;
+}
+</STYLE>
+</HEAD>
+
+<BODY>
+
+<H1>
+<A HREF="http://www.lua.org/"><IMG SRC="logo.gif" ALT="Lua"></A>
+Welcome to Lua 5.4
+</H1>
+
+<DIV CLASS="menubar">
+<A HREF="#about">about</A>
+&middot;
+<A HREF="#install">installation</A>
+&middot;
+<A HREF="#changes">changes</A>
+&middot;
+<A HREF="#license">license</A>
+&middot;
+<A HREF="contents.html">reference manual</A>
+</DIV>
+
+<H2><A NAME="about">About Lua</A></H2>
+<P>
+Lua is a powerful, efficient, lightweight, embeddable scripting language
+developed by a
+<A HREF="http://www.lua.org/authors.html">team</A>
+at
+<A HREF="http://www.puc-rio.br/">PUC-Rio</A>,
+the Pontifical Catholic University of Rio de Janeiro in Brazil.
+Lua is
+<A HREF="#license">free software</A>
+used in
+<A HREF="http://www.lua.org/uses.html">many products and projects</A>
+around the world.
+
+<P>
+Lua's
+<A HREF="http://www.lua.org/">official web site</A>
+provides complete information
+about Lua,
+including
+an
+<A HREF="http://www.lua.org/about.html">executive summary</A>
+and
+updated
+<A HREF="http://www.lua.org/docs.html">documentation</A>,
+especially the
+<A HREF="http://www.lua.org/manual/5.4/">reference manual</A>,
+which may differ slightly from the
+<A HREF="contents.html">local copy</A>
+distributed in this package.
+
+<H2><A NAME="install">Installing Lua</A></H2>
+<P>
+Lua is distributed in
+<A HREF="http://www.lua.org/ftp/">source</A>
+form.
+You need to build it before using it.
+Building Lua should be straightforward
+because
+Lua is implemented in pure ANSI C and compiles unmodified in all known
+platforms that have an ANSI C compiler.
+Lua also compiles unmodified as C++.
+The instructions given below for building Lua are for Unix-like platforms,
+such as Linux and Mac OS X.
+See also
+<A HREF="#other">instructions for other systems</A>
+and
+<A HREF="#customization">customization options</A>.
+
+<P>
+If you don't have the time or the inclination to compile Lua yourself,
+get a binary from
+<A HREF="http://lua-users.org/wiki/LuaBinaries">LuaBinaries</A>.
+Try also
+<A HREF="http://luadist.org/">LuaDist</A>,
+a multi-platform distribution of Lua that includes batteries.
+
+<H3>Building Lua</H3>
+<P>
+In most common Unix-like platforms, simply do "<KBD>make</KBD>".
+Here are the details.
+
+<OL>
+<LI>
+Open a terminal window and move to
+the top-level directory, which is named <TT>lua-5.4.0</TT>.
+The <TT>Makefile</TT> there controls both the build process and the installation process.
+<P>
+<LI>
+  Do "<KBD>make</KBD>". The <TT>Makefile</TT> will guess your platform and build Lua for it.
+<P>
+<LI>
+  If the guess failed, do "<KBD>make help</KBD>" and see if your platform is listed.
+  The platforms currently supported are:
+<P>
+<P CLASS="display">
+   guess aix bsd c89 freebsd generic linux linux-readline macosx mingw posix solaris
+</P>
+<P>
+  If your platform is listed, just do "<KBD>make xxx</KBD>", where xxx
+  is your platform name.
+<P>
+  If your platform is not listed, try the closest one or posix, generic,
+  c89, in this order.
+<P>
+<LI>
+The compilation takes only a few moments
+and produces three files in the <TT>src</TT> directory:
+lua (the interpreter),
+luac (the compiler),
+and liblua.a (the library).
+<P>
+<LI>
+  To check that Lua has been built correctly, do "<KBD>make test</KBD>"
+  after building Lua. This will run the interpreter and print its version.
+</OL>
+<P>
+If you're running Linux, try "<KBD>make linux-readline</KBD>" to build the interactive Lua interpreter with handy line-editing and history capabilities.
+If you get compilation errors,
+make sure you have installed the <TT>readline</TT> development package
+(which is probably named <TT>libreadline-dev</TT> or <TT>readline-devel</TT>).
+If you get link errors after that,
+then try "<KBD>make linux-readline MYLIBS=-ltermcap</KBD>".
+
+<H3>Installing Lua</H3>
+<P>
+  Once you have built Lua, you may want to install it in an official
+  place in your system. In this case, do "<KBD>make install</KBD>". The official
+  place and the way to install files are defined in the <TT>Makefile</TT>. You'll
+  probably need the right permissions to install files, and so may need to do "<KBD>sudo make install</KBD>".
+
+<P>
+  To build and install Lua in one step, do "<KBD>make all install</KBD>",
+  or "<KBD>make xxx install</KBD>",
+  where xxx is your platform name.
+
+<P>
+  To install Lua locally after building it, do "<KBD>make local</KBD>".
+  This will create a directory <TT>install</TT> with subdirectories
+  <TT>bin</TT>, <TT>include</TT>, <TT>lib</TT>, <TT>man</TT>, <TT>share</TT>,
+  and install Lua as listed below.
+
+  To install Lua locally, but in some other directory, do
+  "<KBD>make install INSTALL_TOP=xxx</KBD>", where xxx is your chosen directory.
+  The installation starts in the <TT>src</TT> and <TT>doc</TT> directories,
+  so take care if <TT>INSTALL_TOP</TT> is not an absolute path.
+
+<DL CLASS="display">
+<DT>
+    bin:
+<DD>
+    lua luac
+<DT>
+    include:
+<DD>
+    lua.h luaconf.h lualib.h lauxlib.h lua.hpp
+<DT>
+    lib:
+<DD>
+    liblua.a
+<DT>
+    man/man1:
+<DD>
+    lua.1 luac.1
+</DL>
+
+<P>
+  These are the only directories you need for development.
+  If you only want to run Lua programs,
+  you only need the files in <TT>bin</TT> and <TT>man</TT>.
+  The files in <TT>include</TT> and <TT>lib</TT> are needed for
+  embedding Lua in C or C++ programs.
+
+<H3><A NAME="customization">Customization</A></H3>
+<P>
+  Three kinds of things can be customized by editing a file:
+<UL>
+    <LI> Where and how to install Lua &mdash; edit <TT>Makefile</TT>.
+    <LI> How to build Lua &mdash; edit <TT>src/Makefile</TT>.
+    <LI> Lua features &mdash; edit <TT>src/luaconf.h</TT>.
+</UL>
+
+<P>
+  You don't actually need to edit the Makefiles because you may set the
+  relevant variables in the command line when invoking make.
+  Nevertheless, it's probably best to edit and save the Makefiles to
+  record the changes you've made.
+
+<P>
+  On the other hand, if you need to customize some Lua features, you'll need
+  to edit <TT>src/luaconf.h</TT> before building and installing Lua.
+  The edited file will be the one installed, and
+  it will be used by any Lua clients that you build, to ensure consistency.
+  Further customization is available to experts by editing the Lua sources.
+
+<H3><A NAME="other">Building Lua on other systems</A></H3>
+<P>
+  If you're not using the usual Unix tools, then the instructions for
+  building Lua depend on the compiler you use. You'll need to create
+  projects (or whatever your compiler uses) for building the library,
+  the interpreter, and the compiler, as follows:
+
+<DL CLASS="display">
+<DT>
+library:
+<DD>
+lapi.c lcode.c lctype.c ldebug.c ldo.c ldump.c lfunc.c lgc.c llex.c lmem.c lobject.c lopcodes.c lparser.c lstate.c lstring.c ltable.c ltm.c lundump.c lvm.c lzio.c
+lauxlib.c lbaselib.c lcorolib.c ldblib.c liolib.c lmathlib.c loadlib.c loslib.c lstrlib.c ltablib.c lutf8lib.c linit.c
+<DT>
+interpreter:
+<DD>
+  library, lua.c
+<DT>
+compiler:
+<DD>
+  library, luac.c
+</DL>
+
+<P>
+  To use Lua as a library in your own programs, you'll need to know how to
+  create and use libraries with your compiler. Moreover, to dynamically load
+  C libraries for Lua, you'll need to know how to create dynamic libraries
+  and you'll need to make sure that the Lua API functions are accessible to
+  those dynamic libraries &mdash; but <EM>don't</EM> link the Lua library
+  into each dynamic library. For Unix, we recommend that the Lua library
+  be linked statically into the host program and its symbols exported for
+  dynamic linking; <TT>src/Makefile</TT> does this for the Lua interpreter.
+  For Windows, we recommend that the Lua library be a DLL.
+  In all cases, the compiler luac should be linked statically.
+
+<P>
+  As mentioned above, you may edit <TT>src/luaconf.h</TT> to customize
+  some features before building Lua.
+
+<H2><A NAME="changes">Changes since Lua 5.3</A></H2>
+<P>
+Here are the main changes introduced in Lua 5.4.
+The
+<A HREF="contents.html">reference manual</A>
+lists the
+<A HREF="manual.html#8">incompatibilities</A> that had to be introduced.
+
+<H3>Main changes</H3>
+<UL>
+<LI> new generational mode for garbage collection
+<LI> to-be-closed variables
+<LI> const variables
+<LI> userdata can have multiple user values
+<LI> new implementation for math.random
+<LI> warning system
+<LI> debug information about function arguments and returns
+<LI> new semantics for the integer 'for' loop
+<LI> optional 'init' argument to 'string.gmatch'
+<LI> new functions 'lua_resetthread' and 'coroutine.close'
+<LI> string-to-number coercions moved to the string library
+<LI> allocation function allowed to fail when shrinking a memory block
+<LI> new format '%p' in 'string.format'
+<LI> utf8 library accepts codepoints up to 2^31
+</UL>
+
+<H2><A NAME="license">License</A></H2>
+<P>
+<A HREF="http://www.opensource.org/docs/definition.php">
+<IMG SRC="osi-certified-72x60.png" ALIGN="right" ALT="[osi certified]" STYLE="padding-left: 30px ;">
+</A>
+Lua is free software distributed under the terms of the
+<A HREF="http://www.opensource.org/licenses/mit-license.html">MIT license</A>
+reproduced below;
+it may be used for any purpose, including commercial purposes,
+at absolutely no cost without having to ask us.
+
+The only requirement is that if you do use Lua,
+then you should give us credit by including the appropriate copyright notice somewhere in your product or its documentation.
+
+For details, see
+<A HREF="http://www.lua.org/license.html">this</A>.
+
+<BLOCKQUOTE STYLE="padding-bottom: 0em">
+Copyright &copy; 1994&ndash;2020 Lua.org, PUC-Rio.
+
+<P>
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+<P>
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+<P>
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+</BLOCKQUOTE>
+<P>
+
+<P CLASS="footer">
+Last update:
+Fri May  1 19:33:31 UTC 2020
+</P>
+<!--
+Last change: revised for Lua 5.4.0 (final)
+-->
+
+</BODY>
+</HTML>
diff --git a/test/external/lua-5.4.0/src/.gitignore b/test/external/lua-5.4.0/src/.gitignore
new file mode 100644
index 0000000..b58dcf6
--- /dev/null
+++ b/test/external/lua-5.4.0/src/.gitignore
@@ -0,0 +1,2 @@
+*.o
+lua
diff --git a/test/external/lua-5.4.0/src/Makefile b/test/external/lua-5.4.0/src/Makefile
new file mode 100644
index 0000000..f284d1d
--- /dev/null
+++ b/test/external/lua-5.4.0/src/Makefile
@@ -0,0 +1,220 @@
+# Makefile for building Lua
+# See ../doc/readme.html for installation and customization instructions.
+
+# == CHANGE THE SETTINGS BELOW TO SUIT YOUR ENVIRONMENT =======================
+
+# Your platform. See PLATS for possible values.
+PLAT= guess
+
+CC= ../../../../antcc -std=c99
+CFLAGS= -O2 -Wall -Wextra -DLUA_COMPAT_5_3 $(SYSCFLAGS) $(MYCFLAGS)
+LDFLAGS= $(SYSLDFLAGS) $(MYLDFLAGS)
+LIBS= -lm $(SYSLIBS) $(MYLIBS)
+
+AR= ar rcu
+RANLIB= ranlib
+RM= rm -f
+UNAME= uname
+
+SYSCFLAGS=
+SYSLDFLAGS=
+SYSLIBS=
+
+MYCFLAGS=
+MYLDFLAGS=
+MYLIBS=
+MYOBJS=
+
+# Special flags for compiler modules; -Os reduces code size.
+CMCFLAGS= -Os
+
+# == END OF USER SETTINGS -- NO NEED TO CHANGE ANYTHING BELOW THIS LINE =======
+
+PLATS= guess aix bsd c89 freebsd generic linux linux-readline macosx mingw posix solaris
+
+LUA_A=	liblua.a
+CORE_O=	lapi.o lcode.o lctype.o ldebug.o ldo.o ldump.o lfunc.o lgc.o llex.o lmem.o lobject.o lopcodes.o lparser.o lstate.o lstring.o ltable.o ltm.o lundump.o lvm.o lzio.o
+LIB_O=	lauxlib.o lbaselib.o lcorolib.o ldblib.o liolib.o lmathlib.o loadlib.o loslib.o lstrlib.o ltablib.o lutf8lib.o linit.o
+BASE_O= $(CORE_O) $(LIB_O) $(MYOBJS)
+
+LUA_T=	lua
+LUA_O=	lua.o
+
+LUAC_T=	luac
+LUAC_O=	luac.o
+
+ALL_O= $(BASE_O) $(LUA_O) $(LUAC_O)
+ALL_T= $(LUA_A) $(LUA_T) $(LUAC_T)
+ALL_A= $(LUA_A)
+
+# Targets start here.
+default: $(PLAT)
+
+all:	$(ALL_T)
+
+o:	$(ALL_O)
+
+a:	$(ALL_A)
+
+$(LUA_A): $(BASE_O)
+	$(AR) $@ $(BASE_O)
+	$(RANLIB) $@
+
+$(LUA_T): $(LUA_O) $(LUA_A)
+	$(CC) -o $@ $(LDFLAGS) $(LUA_O) $(LUA_A) $(LIBS)
+
+$(LUAC_T): $(LUAC_O) $(LUA_A)
+	$(CC) -o $@ $(LDFLAGS) $(LUAC_O) $(LUA_A) $(LIBS)
+
+test:
+	./lua -v
+
+clean:
+	$(RM) $(ALL_T) $(ALL_O)
+
+depend:
+	@$(CC) $(CFLAGS) -MM l*.c
+
+echo:
+	@echo "PLAT= $(PLAT)"
+	@echo "CC= $(CC)"
+	@echo "CFLAGS= $(CFLAGS)"
+	@echo "LDFLAGS= $(SYSLDFLAGS)"
+	@echo "LIBS= $(LIBS)"
+	@echo "AR= $(AR)"
+	@echo "RANLIB= $(RANLIB)"
+	@echo "RM= $(RM)"
+	@echo "UNAME= $(UNAME)"
+
+# Convenience targets for popular platforms.
+ALL= all
+
+help:
+	@echo "Do 'make PLATFORM' where PLATFORM is one of these:"
+	@echo "   $(PLATS)"
+	@echo "See doc/readme.html for complete instructions."
+
+guess:
+	@echo Guessing `$(UNAME)`
+	@$(MAKE) `$(UNAME)`
+
+AIX aix:
+	$(MAKE) $(ALL) CC="xlc" CFLAGS="-O2 -DLUA_USE_POSIX -DLUA_USE_DLOPEN" SYSLIBS="-ldl" SYSLDFLAGS="-brtl -bexpall"
+
+bsd:
+	$(MAKE) $(ALL) SYSCFLAGS="-DLUA_USE_POSIX -DLUA_USE_DLOPEN" SYSLIBS="-Wl,-E"
+
+c89:
+	$(MAKE) $(ALL) SYSCFLAGS="-DLUA_USE_C89" CC="gcc -std=c89"
+	@echo ''
+	@echo '*** C89 does not guarantee 64-bit integers for Lua.'
+	@echo ''
+
+FreeBSD NetBSD OpenBSD freebsd:
+	$(MAKE) $(ALL) SYSCFLAGS="-DLUA_USE_LINUX -DLUA_USE_READLINE -I/usr/include/edit" SYSLIBS="-Wl,-E -ledit" CC="cc"
+
+generic: $(ALL)
+
+Linux linux:	linux-noreadline
+
+linux-noreadline:
+	$(MAKE) $(ALL) SYSCFLAGS="-DLUA_USE_LINUX" SYSLIBS="-Wl,-E -ldl"
+
+linux-readline:
+	$(MAKE) $(ALL) SYSCFLAGS="-DLUA_USE_LINUX -DLUA_USE_READLINE" SYSLIBS="-Wl,-E -ldl -lreadline"
+
+Darwin macos macosx:
+	$(MAKE) $(ALL) SYSCFLAGS="-DLUA_USE_MACOSX -DLUA_USE_READLINE" SYSLIBS="-lreadline"
+
+mingw:
+	$(MAKE) "LUA_A=lua54.dll" "LUA_T=lua.exe" \
+	"AR=$(CC) -shared -o" "RANLIB=strip --strip-unneeded" \
+	"SYSCFLAGS=-DLUA_BUILD_AS_DLL" "SYSLIBS=" "SYSLDFLAGS=-s" lua.exe
+	$(MAKE) "LUAC_T=luac.exe" luac.exe
+
+posix:
+	$(MAKE) $(ALL) SYSCFLAGS="-DLUA_USE_POSIX"
+
+SunOS solaris:
+	$(MAKE) $(ALL) SYSCFLAGS="-DLUA_USE_POSIX -DLUA_USE_DLOPEN -D_REENTRANT" SYSLIBS="-ldl"
+
+# Targets that do not create files (not all makes understand .PHONY).
+.PHONY: all $(PLATS) help test clean default o a depend echo
+
+# Compiler modules may use special flags.
+llex.o:
+	$(CC) $(CFLAGS) $(CMCFLAGS) -c llex.c
+
+lparser.o:
+	$(CC) $(CFLAGS) $(CMCFLAGS) -c lparser.c
+
+lcode.o:
+	$(CC) $(CFLAGS) $(CMCFLAGS) -c lcode.c
+
+# DO NOT DELETE
+
+lapi.o: lapi.c lprefix.h lua.h luaconf.h lapi.h llimits.h lstate.h \
+ lobject.h ltm.h lzio.h lmem.h ldebug.h ldo.h lfunc.h lgc.h lstring.h \
+ ltable.h lundump.h lvm.h
+lauxlib.o: lauxlib.c lprefix.h lua.h luaconf.h lauxlib.h
+lbaselib.o: lbaselib.c lprefix.h lua.h luaconf.h lauxlib.h lualib.h
+lcode.o: lcode.c lprefix.h lua.h luaconf.h lcode.h llex.h lobject.h \
+ llimits.h lzio.h lmem.h lopcodes.h lparser.h ldebug.h lstate.h ltm.h \
+ ldo.h lgc.h lstring.h ltable.h lvm.h
+lcorolib.o: lcorolib.c lprefix.h lua.h luaconf.h lauxlib.h lualib.h
+lctype.o: lctype.c lprefix.h lctype.h lua.h luaconf.h llimits.h
+ldblib.o: ldblib.c lprefix.h lua.h luaconf.h lauxlib.h lualib.h
+ldebug.o: ldebug.c lprefix.h lua.h luaconf.h lapi.h llimits.h lstate.h \
+ lobject.h ltm.h lzio.h lmem.h lcode.h llex.h lopcodes.h lparser.h \
+ ldebug.h ldo.h lfunc.h lstring.h lgc.h ltable.h lvm.h
+ldo.o: ldo.c lprefix.h lua.h luaconf.h lapi.h llimits.h lstate.h \
+ lobject.h ltm.h lzio.h lmem.h ldebug.h ldo.h lfunc.h lgc.h lopcodes.h \
+ lparser.h lstring.h ltable.h lundump.h lvm.h
+ldump.o: ldump.c lprefix.h lua.h luaconf.h lobject.h llimits.h lstate.h \
+ ltm.h lzio.h lmem.h lundump.h
+lfunc.o: lfunc.c lprefix.h lua.h luaconf.h ldebug.h lstate.h lobject.h \
+ llimits.h ltm.h lzio.h lmem.h ldo.h lfunc.h lgc.h
+lgc.o: lgc.c lprefix.h lua.h luaconf.h ldebug.h lstate.h lobject.h \
+ llimits.h ltm.h lzio.h lmem.h ldo.h lfunc.h lgc.h lstring.h ltable.h
+linit.o: linit.c lprefix.h lua.h luaconf.h lualib.h lauxlib.h
+liolib.o: liolib.c lprefix.h lua.h luaconf.h lauxlib.h lualib.h
+llex.o: llex.c lprefix.h lua.h luaconf.h lctype.h llimits.h ldebug.h \
+ lstate.h lobject.h ltm.h lzio.h lmem.h ldo.h lgc.h llex.h lparser.h \
+ lstring.h ltable.h
+lmathlib.o: lmathlib.c lprefix.h lua.h luaconf.h lauxlib.h lualib.h
+lmem.o: lmem.c lprefix.h lua.h luaconf.h ldebug.h lstate.h lobject.h \
+ llimits.h ltm.h lzio.h lmem.h ldo.h lgc.h
+loadlib.o: loadlib.c lprefix.h lua.h luaconf.h lauxlib.h lualib.h
+lobject.o: lobject.c lprefix.h lua.h luaconf.h lctype.h llimits.h \
+ ldebug.h lstate.h lobject.h ltm.h lzio.h lmem.h ldo.h lstring.h lgc.h \
+ lvm.h
+lopcodes.o: lopcodes.c lprefix.h lopcodes.h llimits.h lua.h luaconf.h
+loslib.o: loslib.c lprefix.h lua.h luaconf.h lauxlib.h lualib.h
+lparser.o: lparser.c lprefix.h lua.h luaconf.h lcode.h llex.h lobject.h \
+ llimits.h lzio.h lmem.h lopcodes.h lparser.h ldebug.h lstate.h ltm.h \
+ ldo.h lfunc.h lstring.h lgc.h ltable.h
+lstate.o: lstate.c lprefix.h lua.h luaconf.h lapi.h llimits.h lstate.h \
+ lobject.h ltm.h lzio.h lmem.h ldebug.h ldo.h lfunc.h lgc.h llex.h \
+ lstring.h ltable.h
+lstring.o: lstring.c lprefix.h lua.h luaconf.h ldebug.h lstate.h \
+ lobject.h llimits.h ltm.h lzio.h lmem.h ldo.h lstring.h lgc.h
+lstrlib.o: lstrlib.c lprefix.h lua.h luaconf.h lauxlib.h lualib.h
+ltable.o: ltable.c lprefix.h lua.h luaconf.h ldebug.h lstate.h lobject.h \
+ llimits.h ltm.h lzio.h lmem.h ldo.h lgc.h lstring.h ltable.h lvm.h
+ltablib.o: ltablib.c lprefix.h lua.h luaconf.h lauxlib.h lualib.h
+ltm.o: ltm.c lprefix.h lua.h luaconf.h ldebug.h lstate.h lobject.h \
+ llimits.h ltm.h lzio.h lmem.h ldo.h lgc.h lstring.h ltable.h lvm.h
+lua.o: lua.c lprefix.h lua.h luaconf.h lauxlib.h lualib.h
+luac.o: luac.c lprefix.h lua.h luaconf.h lauxlib.h ldebug.h lstate.h \
+ lobject.h llimits.h ltm.h lzio.h lmem.h lopcodes.h lopnames.h lundump.h
+lundump.o: lundump.c lprefix.h lua.h luaconf.h ldebug.h lstate.h \
+ lobject.h llimits.h ltm.h lzio.h lmem.h ldo.h lfunc.h lstring.h lgc.h \
+ lundump.h
+lutf8lib.o: lutf8lib.c lprefix.h lua.h luaconf.h lauxlib.h lualib.h
+lvm.o: lvm.c lprefix.h lua.h luaconf.h ldebug.h lstate.h lobject.h \
+ llimits.h ltm.h lzio.h lmem.h ldo.h lfunc.h lgc.h lopcodes.h lstring.h \
+ ltable.h lvm.h ljumptab.h
+lzio.o: lzio.c lprefix.h lua.h luaconf.h llimits.h lmem.h lstate.h \
+ lobject.h ltm.h lzio.h
+
+# (end of Makefile)
diff --git a/test/external/lua-5.4.0/src/lapi.c b/test/external/lua-5.4.0/src/lapi.c
new file mode 100644
index 0000000..3e24781
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lapi.c
@@ -0,0 +1,1411 @@
+/*
+** $Id: lapi.c $
+** Lua API
+** See Copyright Notice in lua.h
+*/
+
+#define lapi_c
+#define LUA_CORE
+
+#include "lprefix.h"
+
+
+#include <limits.h>
+#include <stdarg.h>
+#include <string.h>
+
+#include "lua.h"
+
+#include "lapi.h"
+#include "ldebug.h"
+#include "ldo.h"
+#include "lfunc.h"
+#include "lgc.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "ltm.h"
+#include "lundump.h"
+#include "lvm.h"
+
+
+
+const char lua_ident[] =
+  "$LuaVersion: " LUA_COPYRIGHT " $"
+  "$LuaAuthors: " LUA_AUTHORS " $";
+
+
+
+/*
+** Test for a valid index.
+** '!ttisnil(o)' implies 'o != &G(L)->nilvalue', so it is not needed.
+** However, it covers the most common cases in a faster way.
+*/
+#define isvalid(L, o)	(!ttisnil(o) || o != &G(L)->nilvalue)
+
+
+/* test for pseudo index */
+#define ispseudo(i)		((i) <= LUA_REGISTRYINDEX)
+
+/* test for upvalue */
+#define isupvalue(i)		((i) < LUA_REGISTRYINDEX)
+
+
+static TValue *index2value (lua_State *L, int idx) {
+  CallInfo *ci = L->ci;
+  if (idx > 0) {
+    StkId o = ci->func + idx;
+    api_check(L, idx <= L->ci->top - (ci->func + 1), "unacceptable index");
+    if (o >= L->top) return &G(L)->nilvalue;
+    else return s2v(o);
+  }
+  else if (!ispseudo(idx)) {  /* negative index */
+    api_check(L, idx != 0 && -idx <= L->top - (ci->func + 1), "invalid index");
+    return s2v(L->top + idx);
+  }
+  else if (idx == LUA_REGISTRYINDEX)
+    return &G(L)->l_registry;
+  else {  /* upvalues */
+    idx = LUA_REGISTRYINDEX - idx;
+    api_check(L, idx <= MAXUPVAL + 1, "upvalue index too large");
+    if (ttislcf(s2v(ci->func)))  /* light C function? */
+      return &G(L)->nilvalue;  /* it has no upvalues */
+    else {
+      CClosure *func = clCvalue(s2v(ci->func));
+      return (idx <= func->nupvalues) ? &func->upvalue[idx-1] : &G(L)->nilvalue;
+    }
+  }
+}
+
+
+static StkId index2stack (lua_State *L, int idx) {
+  CallInfo *ci = L->ci;
+  if (idx > 0) {
+    StkId o = ci->func + idx;
+    api_check(L, o < L->top, "unacceptable index");
+    return o;
+  }
+  else {    /* non-positive index */
+    api_check(L, idx != 0 && -idx <= L->top - (ci->func + 1), "invalid index");
+    api_check(L, !ispseudo(idx), "invalid index");
+    return L->top + idx;
+  }
+}
+
+
+LUA_API int lua_checkstack (lua_State *L, int n) {
+  int res;
+  CallInfo *ci = L->ci;
+  lua_lock(L);
+  api_check(L, n >= 0, "negative 'n'");
+  if (L->stack_last - L->top > n)  /* stack large enough? */
+    res = 1;  /* yes; check is OK */
+  else {  /* no; need to grow stack */
+    int inuse = cast_int(L->top - L->stack) + EXTRA_STACK;
+    if (inuse > LUAI_MAXSTACK - n)  /* can grow without overflow? */
+      res = 0;  /* no */
+    else  /* try to grow stack */
+      res = luaD_growstack(L, n, 0);
+  }
+  if (res && ci->top < L->top + n)
+    ci->top = L->top + n;  /* adjust frame top */
+  lua_unlock(L);
+  return res;
+}
+
+
+LUA_API void lua_xmove (lua_State *from, lua_State *to, int n) {
+  int i;
+  if (from == to) return;
+  lua_lock(to);
+  api_checknelems(from, n);
+  api_check(from, G(from) == G(to), "moving among independent states");
+  api_check(from, to->ci->top - to->top >= n, "stack overflow");
+  from->top -= n;
+  for (i = 0; i < n; i++) {
+    setobjs2s(to, to->top, from->top + i);
+    to->top++;  /* stack already checked by previous 'api_check' */
+  }
+  lua_unlock(to);
+}
+
+
+LUA_API lua_CFunction lua_atpanic (lua_State *L, lua_CFunction panicf) {
+  lua_CFunction old;
+  lua_lock(L);
+  old = G(L)->panic;
+  G(L)->panic = panicf;
+  lua_unlock(L);
+  return old;
+}
+
+
+LUA_API lua_Number lua_version (lua_State *L) {
+  UNUSED(L);
+  return LUA_VERSION_NUM;
+}
+
+
+
+/*
+** basic stack manipulation
+*/
+
+
+/*
+** convert an acceptable stack index into an absolute index
+*/
+LUA_API int lua_absindex (lua_State *L, int idx) {
+  return (idx > 0 || ispseudo(idx))
+         ? idx
+         : cast_int(L->top - L->ci->func) + idx;
+}
+
+
+LUA_API int lua_gettop (lua_State *L) {
+  return cast_int(L->top - (L->ci->func + 1));
+}
+
+
+LUA_API void lua_settop (lua_State *L, int idx) {
+  CallInfo *ci = L->ci;
+  StkId func = ci->func;
+  ptrdiff_t diff;  /* difference for new top */
+  lua_lock(L);
+  if (idx >= 0) {
+    api_check(L, idx <= ci->top - (func + 1), "new top too large");
+    diff = ((func + 1) + idx) - L->top;
+    for (; diff > 0; diff--)
+      setnilvalue(s2v(L->top++));  /* clear new slots */
+  }
+  else {
+    api_check(L, -(idx+1) <= (L->top - (func + 1)), "invalid new top");
+    diff = idx + 1;  /* will "subtract" index (as it is negative) */
+  }
+  if (diff < 0 && hastocloseCfunc(ci->nresults))
+    luaF_close(L, L->top + diff, LUA_OK);
+  L->top += diff;  /* correct top only after closing any upvalue */
+  lua_unlock(L);
+}
+
+
+/*
+** Reverse the stack segment from 'from' to 'to'
+** (auxiliary to 'lua_rotate')
+** Note that we move(copy) only the value inside the stack.
+** (We do not move additional fields that may exist.)
+*/
+static void reverse (lua_State *L, StkId from, StkId to) {
+  for (; from < to; from++, to--) {
+    TValue temp;
+    setobj(L, &temp, s2v(from));
+    setobjs2s(L, from, to);
+    setobj2s(L, to, &temp);
+  }
+}
+
+
+/*
+** Let x = AB, where A is a prefix of length 'n'. Then,
+** rotate x n == BA. But BA == (A^r . B^r)^r.
+*/
+LUA_API void lua_rotate (lua_State *L, int idx, int n) {
+  StkId p, t, m;
+  lua_lock(L);
+  t = L->top - 1;  /* end of stack segment being rotated */
+  p = index2stack(L, idx);  /* start of segment */
+  api_check(L, (n >= 0 ? n : -n) <= (t - p + 1), "invalid 'n'");
+  m = (n >= 0 ? t - n : p - n - 1);  /* end of prefix */
+  reverse(L, p, m);  /* reverse the prefix with length 'n' */
+  reverse(L, m + 1, t);  /* reverse the suffix */
+  reverse(L, p, t);  /* reverse the entire segment */
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_copy (lua_State *L, int fromidx, int toidx) {
+  TValue *fr, *to;
+  lua_lock(L);
+  fr = index2value(L, fromidx);
+  to = index2value(L, toidx);
+  api_check(L, isvalid(L, to), "invalid index");
+  setobj(L, to, fr);
+  if (isupvalue(toidx))  /* function upvalue? */
+    luaC_barrier(L, clCvalue(s2v(L->ci->func)), fr);
+  /* LUA_REGISTRYINDEX does not need gc barrier
+     (collector revisits it before finishing collection) */
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_pushvalue (lua_State *L, int idx) {
+  lua_lock(L);
+  setobj2s(L, L->top, index2value(L, idx));
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+
+/*
+** access functions (stack -> C)
+*/
+
+
+LUA_API int lua_type (lua_State *L, int idx) {
+  const TValue *o = index2value(L, idx);
+  return (isvalid(L, o) ? ttype(o) : LUA_TNONE);
+}
+
+
+LUA_API const char *lua_typename (lua_State *L, int t) {
+  UNUSED(L);
+  api_check(L, LUA_TNONE <= t && t < LUA_NUMTYPES, "invalid type");
+  return ttypename(t);
+}
+
+
+LUA_API int lua_iscfunction (lua_State *L, int idx) {
+  const TValue *o = index2value(L, idx);
+  return (ttislcf(o) || (ttisCclosure(o)));
+}
+
+
+LUA_API int lua_isinteger (lua_State *L, int idx) {
+  const TValue *o = index2value(L, idx);
+  return ttisinteger(o);
+}
+
+
+LUA_API int lua_isnumber (lua_State *L, int idx) {
+  lua_Number n;
+  const TValue *o = index2value(L, idx);
+  return tonumber(o, &n);
+}
+
+
+LUA_API int lua_isstring (lua_State *L, int idx) {
+  const TValue *o = index2value(L, idx);
+  return (ttisstring(o) || cvt2str(o));
+}
+
+
+LUA_API int lua_isuserdata (lua_State *L, int idx) {
+  const TValue *o = index2value(L, idx);
+  return (ttisfulluserdata(o) || ttislightuserdata(o));
+}
+
+
+LUA_API int lua_rawequal (lua_State *L, int index1, int index2) {
+  const TValue *o1 = index2value(L, index1);
+  const TValue *o2 = index2value(L, index2);
+  return (isvalid(L, o1) && isvalid(L, o2)) ? luaV_rawequalobj(o1, o2) : 0;
+}
+
+
+LUA_API void lua_arith (lua_State *L, int op) {
+  lua_lock(L);
+  if (op != LUA_OPUNM && op != LUA_OPBNOT)
+    api_checknelems(L, 2);  /* all other operations expect two operands */
+  else {  /* for unary operations, add fake 2nd operand */
+    api_checknelems(L, 1);
+    setobjs2s(L, L->top, L->top - 1);
+    api_incr_top(L);
+  }
+  /* first operand at top - 2, second at top - 1; result go to top - 2 */
+  luaO_arith(L, op, s2v(L->top - 2), s2v(L->top - 1), L->top - 2);
+  L->top--;  /* remove second operand */
+  lua_unlock(L);
+}
+
+
+LUA_API int lua_compare (lua_State *L, int index1, int index2, int op) {
+  const TValue *o1;
+  const TValue *o2;
+  int i = 0;
+  lua_lock(L);  /* may call tag method */
+  o1 = index2value(L, index1);
+  o2 = index2value(L, index2);
+  if (isvalid(L, o1) && isvalid(L, o2)) {
+    switch (op) {
+      case LUA_OPEQ: i = luaV_equalobj(L, o1, o2); break;
+      case LUA_OPLT: i = luaV_lessthan(L, o1, o2); break;
+      case LUA_OPLE: i = luaV_lessequal(L, o1, o2); break;
+      default: api_check(L, 0, "invalid option");
+    }
+  }
+  lua_unlock(L);
+  return i;
+}
+
+
+LUA_API size_t lua_stringtonumber (lua_State *L, const char *s) {
+  size_t sz = luaO_str2num(s, s2v(L->top));
+  if (sz != 0)
+    api_incr_top(L);
+  return sz;
+}
+
+
+LUA_API lua_Number lua_tonumberx (lua_State *L, int idx, int *pisnum) {
+  lua_Number n = 0;
+  const TValue *o = index2value(L, idx);
+  int isnum = tonumber(o, &n);
+  if (pisnum)
+    *pisnum = isnum;
+  return n;
+}
+
+
+LUA_API lua_Integer lua_tointegerx (lua_State *L, int idx, int *pisnum) {
+  lua_Integer res = 0;
+  const TValue *o = index2value(L, idx);
+  int isnum = tointeger(o, &res);
+  if (pisnum)
+    *pisnum = isnum;
+  return res;
+}
+
+
+LUA_API int lua_toboolean (lua_State *L, int idx) {
+  const TValue *o = index2value(L, idx);
+  return !l_isfalse(o);
+}
+
+
+LUA_API const char *lua_tolstring (lua_State *L, int idx, size_t *len) {
+  TValue *o = index2value(L, idx);
+  if (!ttisstring(o)) {
+    if (!cvt2str(o)) {  /* not convertible? */
+      if (len != NULL) *len = 0;
+      return NULL;
+    }
+    lua_lock(L);  /* 'luaO_tostring' may create a new string */
+    luaO_tostring(L, o);
+    luaC_checkGC(L);
+    o = index2value(L, idx);  /* previous call may reallocate the stack */
+    lua_unlock(L);
+  }
+  if (len != NULL)
+    *len = vslen(o);
+  return svalue(o);
+}
+
+
+LUA_API lua_Unsigned lua_rawlen (lua_State *L, int idx) {
+  const TValue *o = index2value(L, idx);
+  switch (ttypetag(o)) {
+    case LUA_VSHRSTR: return tsvalue(o)->shrlen;
+    case LUA_VLNGSTR: return tsvalue(o)->u.lnglen;
+    case LUA_VUSERDATA: return uvalue(o)->len;
+    case LUA_VTABLE: return luaH_getn(hvalue(o));
+    default: return 0;
+  }
+}
+
+
+LUA_API lua_CFunction lua_tocfunction (lua_State *L, int idx) {
+  const TValue *o = index2value(L, idx);
+  if (ttislcf(o)) return fvalue(o);
+  else if (ttisCclosure(o))
+    return clCvalue(o)->f;
+  else return NULL;  /* not a C function */
+}
+
+
+static void *touserdata (const TValue *o) {
+  switch (ttype(o)) {
+    case LUA_TUSERDATA: return getudatamem(uvalue(o));
+    case LUA_TLIGHTUSERDATA: return pvalue(o);
+    default: return NULL;
+  }
+}
+
+
+LUA_API void *lua_touserdata (lua_State *L, int idx) {
+  const TValue *o = index2value(L, idx);
+  return touserdata(o);
+}
+
+
+LUA_API lua_State *lua_tothread (lua_State *L, int idx) {
+  const TValue *o = index2value(L, idx);
+  return (!ttisthread(o)) ? NULL : thvalue(o);
+}
+
+
+/*
+** Returns a pointer to the internal representation of an object.
+** Note that ANSI C does not allow the conversion of a pointer to
+** function to a 'void*', so the conversion here goes through
+** a 'size_t'. (As the returned pointer is only informative, this
+** conversion should not be a problem.)
+*/
+LUA_API const void *lua_topointer (lua_State *L, int idx) {
+  const TValue *o = index2value(L, idx);
+  switch (ttypetag(o)) {
+    case LUA_VLCF: return cast_voidp(cast_sizet(fvalue(o)));
+    case LUA_VUSERDATA: case LUA_VLIGHTUSERDATA:
+      return touserdata(o);
+    default: {
+      if (iscollectable(o))
+        return gcvalue(o);
+      else
+        return NULL;
+    }
+  }
+}
+
+
+
+/*
+** push functions (C -> stack)
+*/
+
+
+LUA_API void lua_pushnil (lua_State *L) {
+  lua_lock(L);
+  setnilvalue(s2v(L->top));
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_pushnumber (lua_State *L, lua_Number n) {
+  lua_lock(L);
+  setfltvalue(s2v(L->top), n);
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_pushinteger (lua_State *L, lua_Integer n) {
+  lua_lock(L);
+  setivalue(s2v(L->top), n);
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+/*
+** Pushes on the stack a string with given length. Avoid using 's' when
+** 'len' == 0 (as 's' can be NULL in that case), due to later use of
+** 'memcmp' and 'memcpy'.
+*/
+LUA_API const char *lua_pushlstring (lua_State *L, const char *s, size_t len) {
+  TString *ts;
+  lua_lock(L);
+  ts = (len == 0) ? luaS_new(L, "") : luaS_newlstr(L, s, len);
+  setsvalue2s(L, L->top, ts);
+  api_incr_top(L);
+  luaC_checkGC(L);
+  lua_unlock(L);
+  return getstr(ts);
+}
+
+
+LUA_API const char *lua_pushstring (lua_State *L, const char *s) {
+  lua_lock(L);
+  if (s == NULL)
+    setnilvalue(s2v(L->top));
+  else {
+    TString *ts;
+    ts = luaS_new(L, s);
+    setsvalue2s(L, L->top, ts);
+    s = getstr(ts);  /* internal copy's address */
+  }
+  api_incr_top(L);
+  luaC_checkGC(L);
+  lua_unlock(L);
+  return s;
+}
+
+
+LUA_API const char *lua_pushvfstring (lua_State *L, const char *fmt,
+                                      va_list argp) {
+  const char *ret;
+  lua_lock(L);
+  ret = luaO_pushvfstring(L, fmt, argp);
+  luaC_checkGC(L);
+  lua_unlock(L);
+  return ret;
+}
+
+
+LUA_API const char *lua_pushfstring (lua_State *L, const char *fmt, ...) {
+  const char *ret;
+  va_list argp;
+  lua_lock(L);
+  va_start(argp, fmt);
+  ret = luaO_pushvfstring(L, fmt, argp);
+  va_end(argp);
+  luaC_checkGC(L);
+  lua_unlock(L);
+  return ret;
+}
+
+
+LUA_API void lua_pushcclosure (lua_State *L, lua_CFunction fn, int n) {
+  lua_lock(L);
+  if (n == 0) {
+    setfvalue(s2v(L->top), fn);
+    api_incr_top(L);
+  }
+  else {
+    CClosure *cl;
+    api_checknelems(L, n);
+    api_check(L, n <= MAXUPVAL, "upvalue index too large");
+    cl = luaF_newCclosure(L, n);
+    cl->f = fn;
+    L->top -= n;
+    while (n--) {
+      setobj2n(L, &cl->upvalue[n], s2v(L->top + n));
+      /* does not need barrier because closure is white */
+    }
+    setclCvalue(L, s2v(L->top), cl);
+    api_incr_top(L);
+    luaC_checkGC(L);
+  }
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_pushboolean (lua_State *L, int b) {
+  lua_lock(L);
+  if (b)
+    setbtvalue(s2v(L->top));
+  else
+    setbfvalue(s2v(L->top));
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_pushlightuserdata (lua_State *L, void *p) {
+  lua_lock(L);
+  setpvalue(s2v(L->top), p);
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API int lua_pushthread (lua_State *L) {
+  lua_lock(L);
+  setthvalue(L, s2v(L->top), L);
+  api_incr_top(L);
+  lua_unlock(L);
+  return (G(L)->mainthread == L);
+}
+
+
+
+/*
+** get functions (Lua -> stack)
+*/
+
+
+static int auxgetstr (lua_State *L, const TValue *t, const char *k) {
+  const TValue *slot;
+  TString *str = luaS_new(L, k);
+  if (luaV_fastget(L, t, str, slot, luaH_getstr)) {
+    setobj2s(L, L->top, slot);
+    api_incr_top(L);
+  }
+  else {
+    setsvalue2s(L, L->top, str);
+    api_incr_top(L);
+    luaV_finishget(L, t, s2v(L->top - 1), L->top - 1, slot);
+  }
+  lua_unlock(L);
+  return ttype(s2v(L->top - 1));
+}
+
+
+LUA_API int lua_getglobal (lua_State *L, const char *name) {
+  Table *reg = hvalue(&G(L)->l_registry);
+  lua_lock(L);
+  return auxgetstr(L, luaH_getint(reg, LUA_RIDX_GLOBALS), name);
+}
+
+
+LUA_API int lua_gettable (lua_State *L, int idx) {
+  const TValue *slot;
+  TValue *t;
+  lua_lock(L);
+  t = index2value(L, idx);
+  if (luaV_fastget(L, t, s2v(L->top - 1), slot, luaH_get)) {
+    setobj2s(L, L->top - 1, slot);
+  }
+  else
+    luaV_finishget(L, t, s2v(L->top - 1), L->top - 1, slot);
+  lua_unlock(L);
+  return ttype(s2v(L->top - 1));
+}
+
+
+LUA_API int lua_getfield (lua_State *L, int idx, const char *k) {
+  lua_lock(L);
+  return auxgetstr(L, index2value(L, idx), k);
+}
+
+
+LUA_API int lua_geti (lua_State *L, int idx, lua_Integer n) {
+  TValue *t;
+  const TValue *slot;
+  lua_lock(L);
+  t = index2value(L, idx);
+  if (luaV_fastgeti(L, t, n, slot)) {
+    setobj2s(L, L->top, slot);
+  }
+  else {
+    TValue aux;
+    setivalue(&aux, n);
+    luaV_finishget(L, t, &aux, L->top, slot);
+  }
+  api_incr_top(L);
+  lua_unlock(L);
+  return ttype(s2v(L->top - 1));
+}
+
+
+static int finishrawget (lua_State *L, const TValue *val) {
+  if (isempty(val))  /* avoid copying empty items to the stack */
+    setnilvalue(s2v(L->top));
+  else
+    setobj2s(L, L->top, val);
+  api_incr_top(L);
+  lua_unlock(L);
+  return ttype(s2v(L->top - 1));
+}
+
+
+static Table *gettable (lua_State *L, int idx) {
+  TValue *t = index2value(L, idx);
+  api_check(L, ttistable(t), "table expected");
+  return hvalue(t);
+}
+
+
+LUA_API int lua_rawget (lua_State *L, int idx) {
+  Table *t;
+  const TValue *val;
+  lua_lock(L);
+  api_checknelems(L, 1);
+  t = gettable(L, idx);
+  val = luaH_get(t, s2v(L->top - 1));
+  L->top--;  /* remove key */
+  return finishrawget(L, val);
+}
+
+
+LUA_API int lua_rawgeti (lua_State *L, int idx, lua_Integer n) {
+  Table *t;
+  lua_lock(L);
+  t = gettable(L, idx);
+  return finishrawget(L, luaH_getint(t, n));
+}
+
+
+LUA_API int lua_rawgetp (lua_State *L, int idx, const void *p) {
+  Table *t;
+  TValue k;
+  lua_lock(L);
+  t = gettable(L, idx);
+  setpvalue(&k, cast_voidp(p));
+  return finishrawget(L, luaH_get(t, &k));
+}
+
+
+LUA_API void lua_createtable (lua_State *L, int narray, int nrec) {
+  Table *t;
+  lua_lock(L);
+  t = luaH_new(L);
+  sethvalue2s(L, L->top, t);
+  api_incr_top(L);
+  if (narray > 0 || nrec > 0)
+    luaH_resize(L, t, narray, nrec);
+  luaC_checkGC(L);
+  lua_unlock(L);
+}
+
+
+LUA_API int lua_getmetatable (lua_State *L, int objindex) {
+  const TValue *obj;
+  Table *mt;
+  int res = 0;
+  lua_lock(L);
+  obj = index2value(L, objindex);
+  switch (ttype(obj)) {
+    case LUA_TTABLE:
+      mt = hvalue(obj)->metatable;
+      break;
+    case LUA_TUSERDATA:
+      mt = uvalue(obj)->metatable;
+      break;
+    default:
+      mt = G(L)->mt[ttype(obj)];
+      break;
+  }
+  if (mt != NULL) {
+    sethvalue2s(L, L->top, mt);
+    api_incr_top(L);
+    res = 1;
+  }
+  lua_unlock(L);
+  return res;
+}
+
+
+LUA_API int lua_getiuservalue (lua_State *L, int idx, int n) {
+  TValue *o;
+  int t;
+  lua_lock(L);
+  o = index2value(L, idx);
+  api_check(L, ttisfulluserdata(o), "full userdata expected");
+  if (n <= 0 || n > uvalue(o)->nuvalue) {
+    setnilvalue(s2v(L->top));
+    t = LUA_TNONE;
+  }
+  else {
+    setobj2s(L, L->top, &uvalue(o)->uv[n - 1].uv);
+    t = ttype(s2v(L->top));
+  }
+  api_incr_top(L);
+  lua_unlock(L);
+  return t;
+}
+
+
+/*
+** set functions (stack -> Lua)
+*/
+
+/*
+** t[k] = value at the top of the stack (where 'k' is a string)
+*/
+static void auxsetstr (lua_State *L, const TValue *t, const char *k) {
+  const TValue *slot;
+  TString *str = luaS_new(L, k);
+  api_checknelems(L, 1);
+  if (luaV_fastget(L, t, str, slot, luaH_getstr)) {
+    luaV_finishfastset(L, t, slot, s2v(L->top - 1));
+    L->top--;  /* pop value */
+  }
+  else {
+    setsvalue2s(L, L->top, str);  /* push 'str' (to make it a TValue) */
+    api_incr_top(L);
+    luaV_finishset(L, t, s2v(L->top - 1), s2v(L->top - 2), slot);
+    L->top -= 2;  /* pop value and key */
+  }
+  lua_unlock(L);  /* lock done by caller */
+}
+
+
+LUA_API void lua_setglobal (lua_State *L, const char *name) {
+  Table *reg = hvalue(&G(L)->l_registry);
+  lua_lock(L);  /* unlock done in 'auxsetstr' */
+  auxsetstr(L, luaH_getint(reg, LUA_RIDX_GLOBALS), name);
+}
+
+
+LUA_API void lua_settable (lua_State *L, int idx) {
+  TValue *t;
+  const TValue *slot;
+  lua_lock(L);
+  api_checknelems(L, 2);
+  t = index2value(L, idx);
+  if (luaV_fastget(L, t, s2v(L->top - 2), slot, luaH_get)) {
+    luaV_finishfastset(L, t, slot, s2v(L->top - 1));
+  }
+  else
+    luaV_finishset(L, t, s2v(L->top - 2), s2v(L->top - 1), slot);
+  L->top -= 2;  /* pop index and value */
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_setfield (lua_State *L, int idx, const char *k) {
+  lua_lock(L);  /* unlock done in 'auxsetstr' */
+  auxsetstr(L, index2value(L, idx), k);
+}
+
+
+LUA_API void lua_seti (lua_State *L, int idx, lua_Integer n) {
+  TValue *t;
+  const TValue *slot;
+  lua_lock(L);
+  api_checknelems(L, 1);
+  t = index2value(L, idx);
+  if (luaV_fastgeti(L, t, n, slot)) {
+    luaV_finishfastset(L, t, slot, s2v(L->top - 1));
+  }
+  else {
+    TValue aux;
+    setivalue(&aux, n);
+    luaV_finishset(L, t, &aux, s2v(L->top - 1), slot);
+  }
+  L->top--;  /* pop value */
+  lua_unlock(L);
+}
+
+
+static void aux_rawset (lua_State *L, int idx, TValue *key, int n) {
+  Table *t;
+  TValue *slot;
+  lua_lock(L);
+  api_checknelems(L, n);
+  t = gettable(L, idx);
+  slot = luaH_set(L, t, key);
+  setobj2t(L, slot, s2v(L->top - 1));
+  invalidateTMcache(t);
+  luaC_barrierback(L, obj2gco(t), s2v(L->top - 1));
+  L->top -= n;
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_rawset (lua_State *L, int idx) {
+  aux_rawset(L, idx, s2v(L->top - 2), 2);
+}
+
+
+LUA_API void lua_rawsetp (lua_State *L, int idx, const void *p) {
+  TValue k;
+  setpvalue(&k, cast_voidp(p));
+  aux_rawset(L, idx, &k, 1);
+}
+
+
+LUA_API void lua_rawseti (lua_State *L, int idx, lua_Integer n) {
+  Table *t;
+  lua_lock(L);
+  api_checknelems(L, 1);
+  t = gettable(L, idx);
+  luaH_setint(L, t, n, s2v(L->top - 1));
+  luaC_barrierback(L, obj2gco(t), s2v(L->top - 1));
+  L->top--;
+  lua_unlock(L);
+}
+
+
+LUA_API int lua_setmetatable (lua_State *L, int objindex) {
+  TValue *obj;
+  Table *mt;
+  lua_lock(L);
+  api_checknelems(L, 1);
+  obj = index2value(L, objindex);
+  if (ttisnil(s2v(L->top - 1)))
+    mt = NULL;
+  else {
+    api_check(L, ttistable(s2v(L->top - 1)), "table expected");
+    mt = hvalue(s2v(L->top - 1));
+  }
+  switch (ttype(obj)) {
+    case LUA_TTABLE: {
+      hvalue(obj)->metatable = mt;
+      if (mt) {
+        luaC_objbarrier(L, gcvalue(obj), mt);
+        luaC_checkfinalizer(L, gcvalue(obj), mt);
+      }
+      break;
+    }
+    case LUA_TUSERDATA: {
+      uvalue(obj)->metatable = mt;
+      if (mt) {
+        luaC_objbarrier(L, uvalue(obj), mt);
+        luaC_checkfinalizer(L, gcvalue(obj), mt);
+      }
+      break;
+    }
+    default: {
+      G(L)->mt[ttype(obj)] = mt;
+      break;
+    }
+  }
+  L->top--;
+  lua_unlock(L);
+  return 1;
+}
+
+
+LUA_API int lua_setiuservalue (lua_State *L, int idx, int n) {
+  TValue *o;
+  int res;
+  lua_lock(L);
+  api_checknelems(L, 1);
+  o = index2value(L, idx);
+  api_check(L, ttisfulluserdata(o), "full userdata expected");
+  if (!(cast_uint(n) - 1u < cast_uint(uvalue(o)->nuvalue)))
+    res = 0;  /* 'n' not in [1, uvalue(o)->nuvalue] */
+  else {
+    setobj(L, &uvalue(o)->uv[n - 1].uv, s2v(L->top - 1));
+    luaC_barrierback(L, gcvalue(o), s2v(L->top - 1));
+    res = 1;
+  }
+  L->top--;
+  lua_unlock(L);
+  return res;
+}
+
+
+/*
+** 'load' and 'call' functions (run Lua code)
+*/
+
+
+#define checkresults(L,na,nr) \
+     api_check(L, (nr) == LUA_MULTRET || (L->ci->top - L->top >= (nr) - (na)), \
+	"results from function overflow current stack size")
+
+
+LUA_API void lua_callk (lua_State *L, int nargs, int nresults,
+                        lua_KContext ctx, lua_KFunction k) {
+  StkId func;
+  lua_lock(L);
+  api_check(L, k == NULL || !isLua(L->ci),
+    "cannot use continuations inside hooks");
+  api_checknelems(L, nargs+1);
+  api_check(L, L->status == LUA_OK, "cannot do calls on non-normal thread");
+  checkresults(L, nargs, nresults);
+  func = L->top - (nargs+1);
+  if (k != NULL && yieldable(L)) {  /* need to prepare continuation? */
+    L->ci->u.c.k = k;  /* save continuation */
+    L->ci->u.c.ctx = ctx;  /* save context */
+    luaD_call(L, func, nresults);  /* do the call */
+  }
+  else  /* no continuation or no yieldable */
+    luaD_callnoyield(L, func, nresults);  /* just do the call */
+  adjustresults(L, nresults);
+  lua_unlock(L);
+}
+
+
+
+/*
+** Execute a protected call.
+*/
+struct CallS {  /* data to 'f_call' */
+  StkId func;
+  int nresults;
+};
+
+
+static void f_call (lua_State *L, void *ud) {
+  struct CallS *c = cast(struct CallS *, ud);
+  luaD_callnoyield(L, c->func, c->nresults);
+}
+
+
+
+LUA_API int lua_pcallk (lua_State *L, int nargs, int nresults, int errfunc,
+                        lua_KContext ctx, lua_KFunction k) {
+  struct CallS c;
+  int status;
+  ptrdiff_t func;
+  lua_lock(L);
+  api_check(L, k == NULL || !isLua(L->ci),
+    "cannot use continuations inside hooks");
+  api_checknelems(L, nargs+1);
+  api_check(L, L->status == LUA_OK, "cannot do calls on non-normal thread");
+  checkresults(L, nargs, nresults);
+  if (errfunc == 0)
+    func = 0;
+  else {
+    StkId o = index2stack(L, errfunc);
+    api_check(L, ttisfunction(s2v(o)), "error handler must be a function");
+    func = savestack(L, o);
+  }
+  c.func = L->top - (nargs+1);  /* function to be called */
+  if (k == NULL || !yieldable(L)) {  /* no continuation or no yieldable? */
+    c.nresults = nresults;  /* do a 'conventional' protected call */
+    status = luaD_pcall(L, f_call, &c, savestack(L, c.func), func);
+  }
+  else {  /* prepare continuation (call is already protected by 'resume') */
+    CallInfo *ci = L->ci;
+    ci->u.c.k = k;  /* save continuation */
+    ci->u.c.ctx = ctx;  /* save context */
+    /* save information for error recovery */
+    ci->u2.funcidx = cast_int(savestack(L, c.func));
+    ci->u.c.old_errfunc = L->errfunc;
+    L->errfunc = func;
+    setoah(ci->callstatus, L->allowhook);  /* save value of 'allowhook' */
+    ci->callstatus |= CIST_YPCALL;  /* function can do error recovery */
+    luaD_call(L, c.func, nresults);  /* do the call */
+    ci->callstatus &= ~CIST_YPCALL;
+    L->errfunc = ci->u.c.old_errfunc;
+    status = LUA_OK;  /* if it is here, there were no errors */
+  }
+  adjustresults(L, nresults);
+  lua_unlock(L);
+  return status;
+}
+
+
+LUA_API int lua_load (lua_State *L, lua_Reader reader, void *data,
+                      const char *chunkname, const char *mode) {
+  ZIO z;
+  int status;
+  lua_lock(L);
+  if (!chunkname) chunkname = "?";
+  luaZ_init(L, &z, reader, data);
+  status = luaD_protectedparser(L, &z, chunkname, mode);
+  if (status == LUA_OK) {  /* no errors? */
+    LClosure *f = clLvalue(s2v(L->top - 1));  /* get newly created function */
+    if (f->nupvalues >= 1) {  /* does it have an upvalue? */
+      /* get global table from registry */
+      Table *reg = hvalue(&G(L)->l_registry);
+      const TValue *gt = luaH_getint(reg, LUA_RIDX_GLOBALS);
+      /* set global table as 1st upvalue of 'f' (may be LUA_ENV) */
+      setobj(L, f->upvals[0]->v, gt);
+      luaC_barrier(L, f->upvals[0], gt);
+    }
+  }
+  lua_unlock(L);
+  return status;
+}
+
+
+LUA_API int lua_dump (lua_State *L, lua_Writer writer, void *data, int strip) {
+  int status;
+  TValue *o;
+  lua_lock(L);
+  api_checknelems(L, 1);
+  o = s2v(L->top - 1);
+  if (isLfunction(o))
+    status = luaU_dump(L, getproto(o), writer, data, strip);
+  else
+    status = 1;
+  lua_unlock(L);
+  return status;
+}
+
+
+LUA_API int lua_status (lua_State *L) {
+  return L->status;
+}
+
+
+/*
+** Garbage-collection function
+*/
+LUA_API int lua_gc (lua_State *L, int what, ...) {
+  va_list argp;
+  int res = 0;
+  global_State *g = G(L);
+  lua_lock(L);
+  va_start(argp, what);
+  switch (what) {
+    case LUA_GCSTOP: {
+      g->gcrunning = 0;
+      break;
+    }
+    case LUA_GCRESTART: {
+      luaE_setdebt(g, 0);
+      g->gcrunning = 1;
+      break;
+    }
+    case LUA_GCCOLLECT: {
+      luaC_fullgc(L, 0);
+      break;
+    }
+    case LUA_GCCOUNT: {
+      /* GC values are expressed in Kbytes: #bytes/2^10 */
+      res = cast_int(gettotalbytes(g) >> 10);
+      break;
+    }
+    case LUA_GCCOUNTB: {
+      res = cast_int(gettotalbytes(g) & 0x3ff);
+      break;
+    }
+    case LUA_GCSTEP: {
+      int data = va_arg(argp, int);
+      l_mem debt = 1;  /* =1 to signal that it did an actual step */
+      lu_byte oldrunning = g->gcrunning;
+      g->gcrunning = 1;  /* allow GC to run */
+      if (data == 0) {
+        luaE_setdebt(g, 0);  /* do a basic step */
+        luaC_step(L);
+      }
+      else {  /* add 'data' to total debt */
+        debt = cast(l_mem, data) * 1024 + g->GCdebt;
+        luaE_setdebt(g, debt);
+        luaC_checkGC(L);
+      }
+      g->gcrunning = oldrunning;  /* restore previous state */
+      if (debt > 0 && g->gcstate == GCSpause)  /* end of cycle? */
+        res = 1;  /* signal it */
+      break;
+    }
+    case LUA_GCSETPAUSE: {
+      int data = va_arg(argp, int);
+      res = getgcparam(g->gcpause);
+      setgcparam(g->gcpause, data);
+      break;
+    }
+    case LUA_GCSETSTEPMUL: {
+      int data = va_arg(argp, int);
+      res = getgcparam(g->gcstepmul);
+      setgcparam(g->gcstepmul, data);
+      break;
+    }
+    case LUA_GCISRUNNING: {
+      res = g->gcrunning;
+      break;
+    }
+    case LUA_GCGEN: {
+      int minormul = va_arg(argp, int);
+      int majormul = va_arg(argp, int);
+      res = isdecGCmodegen(g) ? LUA_GCGEN : LUA_GCINC;
+      if (minormul != 0)
+        g->genminormul = minormul;
+      if (majormul != 0)
+        setgcparam(g->genmajormul, majormul);
+      luaC_changemode(L, KGC_GEN);
+      break;
+    }
+    case LUA_GCINC: {
+      int pause = va_arg(argp, int);
+      int stepmul = va_arg(argp, int);
+      int stepsize = va_arg(argp, int);
+      res = isdecGCmodegen(g) ? LUA_GCGEN : LUA_GCINC;
+      if (pause != 0)
+        setgcparam(g->gcpause, pause);
+      if (stepmul != 0)
+        setgcparam(g->gcstepmul, stepmul);
+      if (stepsize != 0)
+        g->gcstepsize = stepsize;
+      luaC_changemode(L, KGC_INC);
+      break;
+    }
+    default: res = -1;  /* invalid option */
+  }
+  va_end(argp);
+  lua_unlock(L);
+  return res;
+}
+
+
+
+/*
+** miscellaneous functions
+*/
+
+
+LUA_API int lua_error (lua_State *L) {
+  lua_lock(L);
+  api_checknelems(L, 1);
+  luaG_errormsg(L);
+  /* code unreachable; will unlock when control actually leaves the kernel */
+  return 0;  /* to avoid warnings */
+}
+
+
+LUA_API int lua_next (lua_State *L, int idx) {
+  Table *t;
+  int more;
+  lua_lock(L);
+  api_checknelems(L, 1);
+  t = gettable(L, idx);
+  more = luaH_next(L, t, L->top - 1);
+  if (more) {
+    api_incr_top(L);
+  }
+  else  /* no more elements */
+    L->top -= 1;  /* remove key */
+  lua_unlock(L);
+  return more;
+}
+
+
+LUA_API void lua_toclose (lua_State *L, int idx) {
+  int nresults;
+  StkId o;
+  lua_lock(L);
+  o = index2stack(L, idx);
+  nresults = L->ci->nresults;
+  api_check(L, L->openupval == NULL || uplevel(L->openupval) <= o,
+               "marked index below or equal new one");
+  luaF_newtbcupval(L, o);  /* create new to-be-closed upvalue */
+  if (!hastocloseCfunc(nresults))  /* function not marked yet? */
+    L->ci->nresults = codeNresults(nresults);  /* mark it */
+  lua_assert(hastocloseCfunc(L->ci->nresults));
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_concat (lua_State *L, int n) {
+  lua_lock(L);
+  api_checknelems(L, n);
+  if (n >= 2) {
+    luaV_concat(L, n);
+  }
+  else if (n == 0) {  /* push empty string */
+    setsvalue2s(L, L->top, luaS_newlstr(L, "", 0));
+    api_incr_top(L);
+  }
+  /* else n == 1; nothing to do */
+  luaC_checkGC(L);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_len (lua_State *L, int idx) {
+  TValue *t;
+  lua_lock(L);
+  t = index2value(L, idx);
+  luaV_objlen(L, L->top, t);
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API lua_Alloc lua_getallocf (lua_State *L, void **ud) {
+  lua_Alloc f;
+  lua_lock(L);
+  if (ud) *ud = G(L)->ud;
+  f = G(L)->frealloc;
+  lua_unlock(L);
+  return f;
+}
+
+
+LUA_API void lua_setallocf (lua_State *L, lua_Alloc f, void *ud) {
+  lua_lock(L);
+  G(L)->ud = ud;
+  G(L)->frealloc = f;
+  lua_unlock(L);
+}
+
+
+void lua_setwarnf (lua_State *L, lua_WarnFunction f, void *ud) {
+  lua_lock(L);
+  G(L)->ud_warn = ud;
+  G(L)->warnf = f;
+  lua_unlock(L);
+}
+
+
+void lua_warning (lua_State *L, const char *msg, int tocont) {
+  lua_lock(L);
+  luaE_warning(L, msg, tocont);
+  lua_unlock(L);
+}
+
+
+
+LUA_API void *lua_newuserdatauv (lua_State *L, size_t size, int nuvalue) {
+  Udata *u;
+  lua_lock(L);
+  api_check(L, 0 <= nuvalue && nuvalue < USHRT_MAX, "invalid value");
+  u = luaS_newudata(L, size, nuvalue);
+  setuvalue(L, s2v(L->top), u);
+  api_incr_top(L);
+  luaC_checkGC(L);
+  lua_unlock(L);
+  return getudatamem(u);
+}
+
+
+
+static const char *aux_upvalue (TValue *fi, int n, TValue **val,
+                                GCObject **owner) {
+  switch (ttypetag(fi)) {
+    case LUA_VCCL: {  /* C closure */
+      CClosure *f = clCvalue(fi);
+      if (!(cast_uint(n) - 1u < cast_uint(f->nupvalues)))
+        return NULL;  /* 'n' not in [1, f->nupvalues] */
+      *val = &f->upvalue[n-1];
+      if (owner) *owner = obj2gco(f);
+      return "";
+    }
+    case LUA_VLCL: {  /* Lua closure */
+      LClosure *f = clLvalue(fi);
+      TString *name;
+      Proto *p = f->p;
+      if (!(cast_uint(n) - 1u  < cast_uint(p->sizeupvalues)))
+        return NULL;  /* 'n' not in [1, p->sizeupvalues] */
+      *val = f->upvals[n-1]->v;
+      if (owner) *owner = obj2gco(f->upvals[n - 1]);
+      name = p->upvalues[n-1].name;
+      return (name == NULL) ? "(no name)" : getstr(name);
+    }
+    default: return NULL;  /* not a closure */
+  }
+}
+
+
+LUA_API const char *lua_getupvalue (lua_State *L, int funcindex, int n) {
+  const char *name;
+  TValue *val = NULL;  /* to avoid warnings */
+  lua_lock(L);
+  name = aux_upvalue(index2value(L, funcindex), n, &val, NULL);
+  if (name) {
+    setobj2s(L, L->top, val);
+    api_incr_top(L);
+  }
+  lua_unlock(L);
+  return name;
+}
+
+
+LUA_API const char *lua_setupvalue (lua_State *L, int funcindex, int n) {
+  const char *name;
+  TValue *val = NULL;  /* to avoid warnings */
+  GCObject *owner = NULL;  /* to avoid warnings */
+  TValue *fi;
+  lua_lock(L);
+  fi = index2value(L, funcindex);
+  api_checknelems(L, 1);
+  name = aux_upvalue(fi, n, &val, &owner);
+  if (name) {
+    L->top--;
+    setobj(L, val, s2v(L->top));
+    luaC_barrier(L, owner, val);
+  }
+  lua_unlock(L);
+  return name;
+}
+
+
+static UpVal **getupvalref (lua_State *L, int fidx, int n, LClosure **pf) {
+  LClosure *f;
+  TValue *fi = index2value(L, fidx);
+  api_check(L, ttisLclosure(fi), "Lua function expected");
+  f = clLvalue(fi);
+  api_check(L, (1 <= n && n <= f->p->sizeupvalues), "invalid upvalue index");
+  if (pf) *pf = f;
+  return &f->upvals[n - 1];  /* get its upvalue pointer */
+}
+
+
+LUA_API void *lua_upvalueid (lua_State *L, int fidx, int n) {
+  TValue *fi = index2value(L, fidx);
+  switch (ttypetag(fi)) {
+    case LUA_VLCL: {  /* lua closure */
+      return *getupvalref(L, fidx, n, NULL);
+    }
+    case LUA_VCCL: {  /* C closure */
+      CClosure *f = clCvalue(fi);
+      api_check(L, 1 <= n && n <= f->nupvalues, "invalid upvalue index");
+      return &f->upvalue[n - 1];
+    }
+    default: {
+      api_check(L, 0, "closure expected");
+      return NULL;
+    }
+  }
+}
+
+
+LUA_API void lua_upvaluejoin (lua_State *L, int fidx1, int n1,
+                                            int fidx2, int n2) {
+  LClosure *f1;
+  UpVal **up1 = getupvalref(L, fidx1, n1, &f1);
+  UpVal **up2 = getupvalref(L, fidx2, n2, NULL);
+  *up1 = *up2;
+  luaC_objbarrier(L, f1, *up1);
+}
+
+
diff --git a/test/external/lua-5.4.0/src/lapi.h b/test/external/lua-5.4.0/src/lapi.h
new file mode 100644
index 0000000..41216b2
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lapi.h
@@ -0,0 +1,47 @@
+/*
+** $Id: lapi.h $
+** Auxiliary functions from Lua API
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lapi_h
+#define lapi_h
+
+
+#include "llimits.h"
+#include "lstate.h"
+
+
+/* Increments 'L->top', checking for stack overflows */
+#define api_incr_top(L)   {L->top++; api_check(L, L->top <= L->ci->top, \
+				"stack overflow");}
+
+
+/*
+** If a call returns too many multiple returns, the callee may not have
+** stack space to accommodate all results. In this case, this macro
+** increases its stack space ('L->ci->top').
+*/
+#define adjustresults(L,nres) \
+    { if ((nres) <= LUA_MULTRET && L->ci->top < L->top) L->ci->top = L->top; }
+
+
+/* Ensure the stack has at least 'n' elements */
+#define api_checknelems(L,n)	api_check(L, (n) < (L->top - L->ci->func), \
+				  "not enough elements in the stack")
+
+
+/*
+** To reduce the overhead of returning from C functions, the presence of
+** to-be-closed variables in these functions is coded in the CallInfo's
+** field 'nresults', in a way that functions with no to-be-closed variables
+** with zero, one, or "all" wanted results have no overhead. Functions
+** with other number of wanted results, as well as functions with
+** variables to be closed, have an extra check.
+*/
+
+#define hastocloseCfunc(n)	((n) < LUA_MULTRET)
+
+#define codeNresults(n)		(-(n) - 3)
+
+#endif
diff --git a/test/external/lua-5.4.0/src/lauxlib.c b/test/external/lua-5.4.0/src/lauxlib.c
new file mode 100644
index 0000000..e3d9be3
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lauxlib.c
@@ -0,0 +1,1057 @@
+/*
+** $Id: lauxlib.c $
+** Auxiliary functions for building Lua libraries
+** See Copyright Notice in lua.h
+*/
+
+#define lauxlib_c
+#define LUA_LIB
+
+#include "lprefix.h"
+
+
+#include <errno.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+
+/*
+** This file uses only the official API of Lua.
+** Any function declared here could be written as an application function.
+*/
+
+#include "lua.h"
+
+#include "lauxlib.h"
+
+
+#if !defined(MAX_SIZET)
+/* maximum value for size_t */
+#define MAX_SIZET	((size_t)(~(size_t)0))
+#endif
+
+
+/*
+** {======================================================
+** Traceback
+** =======================================================
+*/
+
+
+#define LEVELS1	10	/* size of the first part of the stack */
+#define LEVELS2	11	/* size of the second part of the stack */
+
+
+
+/*
+** Search for 'objidx' in table at index -1. ('objidx' must be an
+** absolute index.) Return 1 + string at top if it found a good name.
+*/
+static int findfield (lua_State *L, int objidx, int level) {
+  if (level == 0 || !lua_istable(L, -1))
+    return 0;  /* not found */
+  lua_pushnil(L);  /* start 'next' loop */
+  while (lua_next(L, -2)) {  /* for each pair in table */
+    if (lua_type(L, -2) == LUA_TSTRING) {  /* ignore non-string keys */
+      if (lua_rawequal(L, objidx, -1)) {  /* found object? */
+        lua_pop(L, 1);  /* remove value (but keep name) */
+        return 1;
+      }
+      else if (findfield(L, objidx, level - 1)) {  /* try recursively */
+        /* stack: lib_name, lib_table, field_name (top) */
+        lua_pushliteral(L, ".");  /* place '.' between the two names */
+        lua_replace(L, -3);  /* (in the slot occupied by table) */
+        lua_concat(L, 3);  /* lib_name.field_name */
+        return 1;
+      }
+    }
+    lua_pop(L, 1);  /* remove value */
+  }
+  return 0;  /* not found */
+}
+
+
+/*
+** Search for a name for a function in all loaded modules
+*/
+static int pushglobalfuncname (lua_State *L, lua_Debug *ar) {
+  int top = lua_gettop(L);
+  lua_getinfo(L, "f", ar);  /* push function */
+  lua_getfield(L, LUA_REGISTRYINDEX, LUA_LOADED_TABLE);
+  if (findfield(L, top + 1, 2)) {
+    const char *name = lua_tostring(L, -1);
+    if (strncmp(name, LUA_GNAME ".", 3) == 0) {  /* name start with '_G.'? */
+      lua_pushstring(L, name + 3);  /* push name without prefix */
+      lua_remove(L, -2);  /* remove original name */
+    }
+    lua_copy(L, -1, top + 1);  /* copy name to proper place */
+    lua_settop(L, top + 1);  /* remove table "loaded" and name copy */
+    return 1;
+  }
+  else {
+    lua_settop(L, top);  /* remove function and global table */
+    return 0;
+  }
+}
+
+
+static void pushfuncname (lua_State *L, lua_Debug *ar) {
+  if (pushglobalfuncname(L, ar)) {  /* try first a global name */
+    lua_pushfstring(L, "function '%s'", lua_tostring(L, -1));
+    lua_remove(L, -2);  /* remove name */
+  }
+  else if (*ar->namewhat != '\0')  /* is there a name from code? */
+    lua_pushfstring(L, "%s '%s'", ar->namewhat, ar->name);  /* use it */
+  else if (*ar->what == 'm')  /* main? */
+      lua_pushliteral(L, "main chunk");
+  else if (*ar->what != 'C')  /* for Lua functions, use <file:line> */
+    lua_pushfstring(L, "function <%s:%d>", ar->short_src, ar->linedefined);
+  else  /* nothing left... */
+    lua_pushliteral(L, "?");
+}
+
+
+static int lastlevel (lua_State *L) {
+  lua_Debug ar;
+  int li = 1, le = 1;
+  /* find an upper bound */
+  while (lua_getstack(L, le, &ar)) { li = le; le *= 2; }
+  /* do a binary search */
+  while (li < le) {
+    int m = (li + le)/2;
+    if (lua_getstack(L, m, &ar)) li = m + 1;
+    else le = m;
+  }
+  return le - 1;
+}
+
+
+LUALIB_API void luaL_traceback (lua_State *L, lua_State *L1,
+                                const char *msg, int level) {
+  luaL_Buffer b;
+  lua_Debug ar;
+  int last = lastlevel(L1);
+  int limit2show = (last - level > LEVELS1 + LEVELS2) ? LEVELS1 : -1;
+  luaL_buffinit(L, &b);
+  if (msg) {
+    luaL_addstring(&b, msg);
+    luaL_addchar(&b, '\n');
+  }
+  luaL_addstring(&b, "stack traceback:");
+  while (lua_getstack(L1, level++, &ar)) {
+    if (limit2show-- == 0) {  /* too many levels? */
+      int n = last - level - LEVELS2 + 1;  /* number of levels to skip */
+      lua_pushfstring(L, "\n\t...\t(skipping %d levels)", n);
+      luaL_addvalue(&b);  /* add warning about skip */
+      level += n;  /* and skip to last levels */
+    }
+    else {
+      lua_getinfo(L1, "Slnt", &ar);
+      if (ar.currentline <= 0)
+        lua_pushfstring(L, "\n\t%s: in ", ar.short_src);
+      else
+        lua_pushfstring(L, "\n\t%s:%d: in ", ar.short_src, ar.currentline);
+      luaL_addvalue(&b);
+      pushfuncname(L, &ar);
+      luaL_addvalue(&b);
+      if (ar.istailcall)
+        luaL_addstring(&b, "\n\t(...tail calls...)");
+    }
+  }
+  luaL_pushresult(&b);
+}
+
+/* }====================================================== */
+
+
+/*
+** {======================================================
+** Error-report functions
+** =======================================================
+*/
+
+LUALIB_API int luaL_argerror (lua_State *L, int arg, const char *extramsg) {
+  lua_Debug ar;
+  if (!lua_getstack(L, 0, &ar))  /* no stack frame? */
+    return luaL_error(L, "bad argument #%d (%s)", arg, extramsg);
+  lua_getinfo(L, "n", &ar);
+  if (strcmp(ar.namewhat, "method") == 0) {
+    arg--;  /* do not count 'self' */
+    if (arg == 0)  /* error is in the self argument itself? */
+      return luaL_error(L, "calling '%s' on bad self (%s)",
+                           ar.name, extramsg);
+  }
+  if (ar.name == NULL)
+    ar.name = (pushglobalfuncname(L, &ar)) ? lua_tostring(L, -1) : "?";
+  return luaL_error(L, "bad argument #%d to '%s' (%s)",
+                        arg, ar.name, extramsg);
+}
+
+
+int luaL_typeerror (lua_State *L, int arg, const char *tname) {
+  const char *msg;
+  const char *typearg;  /* name for the type of the actual argument */
+  if (luaL_getmetafield(L, arg, "__name") == LUA_TSTRING)
+    typearg = lua_tostring(L, -1);  /* use the given type name */
+  else if (lua_type(L, arg) == LUA_TLIGHTUSERDATA)
+    typearg = "light userdata";  /* special name for messages */
+  else
+    typearg = luaL_typename(L, arg);  /* standard name */
+  msg = lua_pushfstring(L, "%s expected, got %s", tname, typearg);
+  return luaL_argerror(L, arg, msg);
+}
+
+
+static void tag_error (lua_State *L, int arg, int tag) {
+  luaL_typeerror(L, arg, lua_typename(L, tag));
+}
+
+
+/*
+** The use of 'lua_pushfstring' ensures this function does not
+** need reserved stack space when called.
+*/
+LUALIB_API void luaL_where (lua_State *L, int level) {
+  lua_Debug ar;
+  if (lua_getstack(L, level, &ar)) {  /* check function at level */
+    lua_getinfo(L, "Sl", &ar);  /* get info about it */
+    if (ar.currentline > 0) {  /* is there info? */
+      lua_pushfstring(L, "%s:%d: ", ar.short_src, ar.currentline);
+      return;
+    }
+  }
+  lua_pushfstring(L, "");  /* else, no information available... */
+}
+
+
+/*
+** Again, the use of 'lua_pushvfstring' ensures this function does
+** not need reserved stack space when called. (At worst, it generates
+** an error with "stack overflow" instead of the given message.)
+*/
+LUALIB_API int luaL_error (lua_State *L, const char *fmt, ...) {
+  va_list argp;
+  va_start(argp, fmt);
+  luaL_where(L, 1);
+  lua_pushvfstring(L, fmt, argp);
+  va_end(argp);
+  lua_concat(L, 2);
+  return lua_error(L);
+}
+
+
+LUALIB_API int luaL_fileresult (lua_State *L, int stat, const char *fname) {
+  int en = errno;  /* calls to Lua API may change this value */
+  if (stat) {
+    lua_pushboolean(L, 1);
+    return 1;
+  }
+  else {
+    luaL_pushfail(L);
+    if (fname)
+      lua_pushfstring(L, "%s: %s", fname, strerror(en));
+    else
+      lua_pushstring(L, strerror(en));
+    lua_pushinteger(L, en);
+    return 3;
+  }
+}
+
+
+#if !defined(l_inspectstat)	/* { */
+
+#if defined(LUA_USE_POSIX)
+
+#include <sys/wait.h>
+
+/*
+** use appropriate macros to interpret 'pclose' return status
+*/
+#define l_inspectstat(stat,what)  \
+   if (WIFEXITED(stat)) { stat = WEXITSTATUS(stat); } \
+   else if (WIFSIGNALED(stat)) { stat = WTERMSIG(stat); what = "signal"; }
+
+#else
+
+#define l_inspectstat(stat,what)  /* no op */
+
+#endif
+
+#endif				/* } */
+
+
+LUALIB_API int luaL_execresult (lua_State *L, int stat) {
+  const char *what = "exit";  /* type of termination */
+  if (stat != 0 && errno != 0)  /* error with an 'errno'? */
+    return luaL_fileresult(L, 0, NULL);
+  else {
+    l_inspectstat(stat, what);  /* interpret result */
+    if (*what == 'e' && stat == 0)  /* successful termination? */
+      lua_pushboolean(L, 1);
+    else
+      luaL_pushfail(L);
+    lua_pushstring(L, what);
+    lua_pushinteger(L, stat);
+    return 3;  /* return true/fail,what,code */
+  }
+}
+
+/* }====================================================== */
+
+
+
+/*
+** {======================================================
+** Userdata's metatable manipulation
+** =======================================================
+*/
+
+LUALIB_API int luaL_newmetatable (lua_State *L, const char *tname) {
+  if (luaL_getmetatable(L, tname) != LUA_TNIL)  /* name already in use? */
+    return 0;  /* leave previous value on top, but return 0 */
+  lua_pop(L, 1);
+  lua_createtable(L, 0, 2);  /* create metatable */
+  lua_pushstring(L, tname);
+  lua_setfield(L, -2, "__name");  /* metatable.__name = tname */
+  lua_pushvalue(L, -1);
+  lua_setfield(L, LUA_REGISTRYINDEX, tname);  /* registry.name = metatable */
+  return 1;
+}
+
+
+LUALIB_API void luaL_setmetatable (lua_State *L, const char *tname) {
+  luaL_getmetatable(L, tname);
+  lua_setmetatable(L, -2);
+}
+
+
+LUALIB_API void *luaL_testudata (lua_State *L, int ud, const char *tname) {
+  void *p = lua_touserdata(L, ud);
+  if (p != NULL) {  /* value is a userdata? */
+    if (lua_getmetatable(L, ud)) {  /* does it have a metatable? */
+      luaL_getmetatable(L, tname);  /* get correct metatable */
+      if (!lua_rawequal(L, -1, -2))  /* not the same? */
+        p = NULL;  /* value is a userdata with wrong metatable */
+      lua_pop(L, 2);  /* remove both metatables */
+      return p;
+    }
+  }
+  return NULL;  /* value is not a userdata with a metatable */
+}
+
+
+LUALIB_API void *luaL_checkudata (lua_State *L, int ud, const char *tname) {
+  void *p = luaL_testudata(L, ud, tname);
+  luaL_argexpected(L, p != NULL, ud, tname);
+  return p;
+}
+
+/* }====================================================== */
+
+
+/*
+** {======================================================
+** Argument check functions
+** =======================================================
+*/
+
+LUALIB_API int luaL_checkoption (lua_State *L, int arg, const char *def,
+                                 const char *const lst[]) {
+  const char *name = (def) ? luaL_optstring(L, arg, def) :
+                             luaL_checkstring(L, arg);
+  int i;
+  for (i=0; lst[i]; i++)
+    if (strcmp(lst[i], name) == 0)
+      return i;
+  return luaL_argerror(L, arg,
+                       lua_pushfstring(L, "invalid option '%s'", name));
+}
+
+
+/*
+** Ensures the stack has at least 'space' extra slots, raising an error
+** if it cannot fulfill the request. (The error handling needs a few
+** extra slots to format the error message. In case of an error without
+** this extra space, Lua will generate the same 'stack overflow' error,
+** but without 'msg'.)
+*/
+LUALIB_API void luaL_checkstack (lua_State *L, int space, const char *msg) {
+  if (!lua_checkstack(L, space)) {
+    if (msg)
+      luaL_error(L, "stack overflow (%s)", msg);
+    else
+      luaL_error(L, "stack overflow");
+  }
+}
+
+
+LUALIB_API void luaL_checktype (lua_State *L, int arg, int t) {
+  if (lua_type(L, arg) != t)
+    tag_error(L, arg, t);
+}
+
+
+LUALIB_API void luaL_checkany (lua_State *L, int arg) {
+  if (lua_type(L, arg) == LUA_TNONE)
+    luaL_argerror(L, arg, "value expected");
+}
+
+
+LUALIB_API const char *luaL_checklstring (lua_State *L, int arg, size_t *len) {
+  const char *s = lua_tolstring(L, arg, len);
+  if (!s) tag_error(L, arg, LUA_TSTRING);
+  return s;
+}
+
+
+LUALIB_API const char *luaL_optlstring (lua_State *L, int arg,
+                                        const char *def, size_t *len) {
+  if (lua_isnoneornil(L, arg)) {
+    if (len)
+      *len = (def ? strlen(def) : 0);
+    return def;
+  }
+  else return luaL_checklstring(L, arg, len);
+}
+
+
+LUALIB_API lua_Number luaL_checknumber (lua_State *L, int arg) {
+  int isnum;
+  lua_Number d = lua_tonumberx(L, arg, &isnum);
+  if (!isnum)
+    tag_error(L, arg, LUA_TNUMBER);
+  return d;
+}
+
+
+LUALIB_API lua_Number luaL_optnumber (lua_State *L, int arg, lua_Number def) {
+  return luaL_opt(L, luaL_checknumber, arg, def);
+}
+
+
+static void interror (lua_State *L, int arg) {
+  if (lua_isnumber(L, arg))
+    luaL_argerror(L, arg, "number has no integer representation");
+  else
+    tag_error(L, arg, LUA_TNUMBER);
+}
+
+
+LUALIB_API lua_Integer luaL_checkinteger (lua_State *L, int arg) {
+  int isnum;
+  lua_Integer d = lua_tointegerx(L, arg, &isnum);
+  if (!isnum) {
+    interror(L, arg);
+  }
+  return d;
+}
+
+
+LUALIB_API lua_Integer luaL_optinteger (lua_State *L, int arg,
+                                                      lua_Integer def) {
+  return luaL_opt(L, luaL_checkinteger, arg, def);
+}
+
+/* }====================================================== */
+
+
+/*
+** {======================================================
+** Generic Buffer manipulation
+** =======================================================
+*/
+
+/* userdata to box arbitrary data */
+typedef struct UBox {
+  void *box;
+  size_t bsize;
+} UBox;
+
+
+static void *resizebox (lua_State *L, int idx, size_t newsize) {
+  void *ud;
+  lua_Alloc allocf = lua_getallocf(L, &ud);
+  UBox *box = (UBox *)lua_touserdata(L, idx);
+  void *temp = allocf(ud, box->box, box->bsize, newsize);
+  if (temp == NULL && newsize > 0)  /* allocation error? */
+    luaL_error(L, "not enough memory");
+  box->box = temp;
+  box->bsize = newsize;
+  return temp;
+}
+
+
+static int boxgc (lua_State *L) {
+  resizebox(L, 1, 0);
+  return 0;
+}
+
+
+static const luaL_Reg boxmt[] = {  /* box metamethods */
+  {"__gc", boxgc},
+  {"__close", boxgc},
+  {NULL, NULL}
+};
+
+
+static void newbox (lua_State *L) {
+  UBox *box = (UBox *)lua_newuserdatauv(L, sizeof(UBox), 0);
+  box->box = NULL;
+  box->bsize = 0;
+  if (luaL_newmetatable(L, "_UBOX*"))  /* creating metatable? */
+    luaL_setfuncs(L, boxmt, 0);  /* set its metamethods */
+  lua_setmetatable(L, -2);
+}
+
+
+/*
+** check whether buffer is using a userdata on the stack as a temporary
+** buffer
+*/
+#define buffonstack(B)	((B)->b != (B)->init.b)
+
+
+/*
+** Compute new size for buffer 'B', enough to accommodate extra 'sz'
+** bytes.
+*/
+static size_t newbuffsize (luaL_Buffer *B, size_t sz) {
+  size_t newsize = B->size * 2;  /* double buffer size */
+  if (MAX_SIZET - sz < B->n)  /* overflow in (B->n + sz)? */
+    return luaL_error(B->L, "buffer too large");
+  if (newsize < B->n + sz)  /* double is not big enough? */
+    newsize = B->n + sz;
+  return newsize;
+}
+
+
+/*
+** Returns a pointer to a free area with at least 'sz' bytes in buffer
+** 'B'. 'boxidx' is the relative position in the stack where the
+** buffer's box is or should be.
+*/
+static char *prepbuffsize (luaL_Buffer *B, size_t sz, int boxidx) {
+  if (B->size - B->n >= sz)  /* enough space? */
+    return B->b + B->n;
+  else {
+    lua_State *L = B->L;
+    char *newbuff;
+    size_t newsize = newbuffsize(B, sz);
+    /* create larger buffer */
+    if (buffonstack(B))  /* buffer already has a box? */
+      newbuff = (char *)resizebox(L, boxidx, newsize);  /* resize it */
+    else {  /* no box yet */
+      lua_pushnil(L);  /* reserve slot for final result */
+      newbox(L);  /* create a new box */
+      /* move box (and slot) to its intended position */
+      lua_rotate(L, boxidx - 1, 2);
+      lua_toclose(L, boxidx);
+      newbuff = (char *)resizebox(L, boxidx, newsize);
+      memcpy(newbuff, B->b, B->n * sizeof(char));  /* copy original content */
+    }
+    B->b = newbuff;
+    B->size = newsize;
+    return newbuff + B->n;
+  }
+}
+
+/*
+** returns a pointer to a free area with at least 'sz' bytes
+*/
+LUALIB_API char *luaL_prepbuffsize (luaL_Buffer *B, size_t sz) {
+  return prepbuffsize(B, sz, -1);
+}
+
+
+LUALIB_API void luaL_addlstring (luaL_Buffer *B, const char *s, size_t l) {
+  if (l > 0) {  /* avoid 'memcpy' when 's' can be NULL */
+    char *b = prepbuffsize(B, l, -1);
+    memcpy(b, s, l * sizeof(char));
+    luaL_addsize(B, l);
+  }
+}
+
+
+LUALIB_API void luaL_addstring (luaL_Buffer *B, const char *s) {
+  luaL_addlstring(B, s, strlen(s));
+}
+
+
+LUALIB_API void luaL_pushresult (luaL_Buffer *B) {
+  lua_State *L = B->L;
+  lua_pushlstring(L, B->b, B->n);
+  if (buffonstack(B)) {
+    lua_copy(L, -1, -3);  /* move string to reserved slot */
+    lua_pop(L, 2);  /* pop string and box (closing the box) */
+  }
+}
+
+
+LUALIB_API void luaL_pushresultsize (luaL_Buffer *B, size_t sz) {
+  luaL_addsize(B, sz);
+  luaL_pushresult(B);
+}
+
+
+/*
+** 'luaL_addvalue' is the only function in the Buffer system where the
+** box (if existent) is not on the top of the stack. So, instead of
+** calling 'luaL_addlstring', it replicates the code using -2 as the
+** last argument to 'prepbuffsize', signaling that the box is (or will
+** be) bellow the string being added to the buffer. (Box creation can
+** trigger an emergency GC, so we should not remove the string from the
+** stack before we have the space guaranteed.)
+*/
+LUALIB_API void luaL_addvalue (luaL_Buffer *B) {
+  lua_State *L = B->L;
+  size_t len;
+  const char *s = lua_tolstring(L, -1, &len);
+  char *b = prepbuffsize(B, len, -2);
+  memcpy(b, s, len * sizeof(char));
+  luaL_addsize(B, len);
+  lua_pop(L, 1);  /* pop string */
+}
+
+
+LUALIB_API void luaL_buffinit (lua_State *L, luaL_Buffer *B) {
+  B->L = L;
+  B->b = B->init.b;
+  B->n = 0;
+  B->size = LUAL_BUFFERSIZE;
+}
+
+
+LUALIB_API char *luaL_buffinitsize (lua_State *L, luaL_Buffer *B, size_t sz) {
+  luaL_buffinit(L, B);
+  return prepbuffsize(B, sz, -1);
+}
+
+/* }====================================================== */
+
+
+/*
+** {======================================================
+** Reference system
+** =======================================================
+*/
+
+/* index of free-list header */
+#define freelist	0
+
+
+LUALIB_API int luaL_ref (lua_State *L, int t) {
+  int ref;
+  if (lua_isnil(L, -1)) {
+    lua_pop(L, 1);  /* remove from stack */
+    return LUA_REFNIL;  /* 'nil' has a unique fixed reference */
+  }
+  t = lua_absindex(L, t);
+  lua_rawgeti(L, t, freelist);  /* get first free element */
+  ref = (int)lua_tointeger(L, -1);  /* ref = t[freelist] */
+  lua_pop(L, 1);  /* remove it from stack */
+  if (ref != 0) {  /* any free element? */
+    lua_rawgeti(L, t, ref);  /* remove it from list */
+    lua_rawseti(L, t, freelist);  /* (t[freelist] = t[ref]) */
+  }
+  else  /* no free elements */
+    ref = (int)lua_rawlen(L, t) + 1;  /* get a new reference */
+  lua_rawseti(L, t, ref);
+  return ref;
+}
+
+
+LUALIB_API void luaL_unref (lua_State *L, int t, int ref) {
+  if (ref >= 0) {
+    t = lua_absindex(L, t);
+    lua_rawgeti(L, t, freelist);
+    lua_rawseti(L, t, ref);  /* t[ref] = t[freelist] */
+    lua_pushinteger(L, ref);
+    lua_rawseti(L, t, freelist);  /* t[freelist] = ref */
+  }
+}
+
+/* }====================================================== */
+
+
+/*
+** {======================================================
+** Load functions
+** =======================================================
+*/
+
+typedef struct LoadF {
+  int n;  /* number of pre-read characters */
+  FILE *f;  /* file being read */
+  char buff[BUFSIZ];  /* area for reading file */
+} LoadF;
+
+
+static const char *getF (lua_State *L, void *ud, size_t *size) {
+  LoadF *lf = (LoadF *)ud;
+  (void)L;  /* not used */
+  if (lf->n > 0) {  /* are there pre-read characters to be read? */
+    *size = lf->n;  /* return them (chars already in buffer) */
+    lf->n = 0;  /* no more pre-read characters */
+  }
+  else {  /* read a block from file */
+    /* 'fread' can return > 0 *and* set the EOF flag. If next call to
+       'getF' called 'fread', it might still wait for user input.
+       The next check avoids this problem. */
+    if (feof(lf->f)) return NULL;
+    *size = fread(lf->buff, 1, sizeof(lf->buff), lf->f);  /* read block */
+  }
+  return lf->buff;
+}
+
+
+static int errfile (lua_State *L, const char *what, int fnameindex) {
+  const char *serr = strerror(errno);
+  const char *filename = lua_tostring(L, fnameindex) + 1;
+  lua_pushfstring(L, "cannot %s %s: %s", what, filename, serr);
+  lua_remove(L, fnameindex);
+  return LUA_ERRFILE;
+}
+
+
+static int skipBOM (LoadF *lf) {
+  const char *p = "\xEF\xBB\xBF";  /* UTF-8 BOM mark */
+  int c;
+  lf->n = 0;
+  do {
+    c = getc(lf->f);
+    if (c == EOF || c != *(const unsigned char *)p++) return c;
+    lf->buff[lf->n++] = c;  /* to be read by the parser */
+  } while (*p != '\0');
+  lf->n = 0;  /* prefix matched; discard it */
+  return getc(lf->f);  /* return next character */
+}
+
+
+/*
+** reads the first character of file 'f' and skips an optional BOM mark
+** in its beginning plus its first line if it starts with '#'. Returns
+** true if it skipped the first line.  In any case, '*cp' has the
+** first "valid" character of the file (after the optional BOM and
+** a first-line comment).
+*/
+static int skipcomment (LoadF *lf, int *cp) {
+  int c = *cp = skipBOM(lf);
+  if (c == '#') {  /* first line is a comment (Unix exec. file)? */
+    do {  /* skip first line */
+      c = getc(lf->f);
+    } while (c != EOF && c != '\n');
+    *cp = getc(lf->f);  /* skip end-of-line, if present */
+    return 1;  /* there was a comment */
+  }
+  else return 0;  /* no comment */
+}
+
+
+LUALIB_API int luaL_loadfilex (lua_State *L, const char *filename,
+                                             const char *mode) {
+  LoadF lf;
+  int status, readstatus;
+  int c;
+  int fnameindex = lua_gettop(L) + 1;  /* index of filename on the stack */
+  if (filename == NULL) {
+    lua_pushliteral(L, "=stdin");
+    lf.f = stdin;
+  }
+  else {
+    lua_pushfstring(L, "@%s", filename);
+    lf.f = fopen(filename, "r");
+    if (lf.f == NULL) return errfile(L, "open", fnameindex);
+  }
+  if (skipcomment(&lf, &c))  /* read initial portion */
+    lf.buff[lf.n++] = '\n';  /* add line to correct line numbers */
+  if (c == LUA_SIGNATURE[0] && filename) {  /* binary file? */
+    lf.f = freopen(filename, "rb", lf.f);  /* reopen in binary mode */
+    if (lf.f == NULL) return errfile(L, "reopen", fnameindex);
+    skipcomment(&lf, &c);  /* re-read initial portion */
+  }
+  if (c != EOF)
+    lf.buff[lf.n++] = c;  /* 'c' is the first character of the stream */
+  status = lua_load(L, getF, &lf, lua_tostring(L, -1), mode);
+  readstatus = ferror(lf.f);
+  if (filename) fclose(lf.f);  /* close file (even in case of errors) */
+  if (readstatus) {
+    lua_settop(L, fnameindex);  /* ignore results from 'lua_load' */
+    return errfile(L, "read", fnameindex);
+  }
+  lua_remove(L, fnameindex);
+  return status;
+}
+
+
+typedef struct LoadS {
+  const char *s;
+  size_t size;
+} LoadS;
+
+
+static const char *getS (lua_State *L, void *ud, size_t *size) {
+  LoadS *ls = (LoadS *)ud;
+  (void)L;  /* not used */
+  if (ls->size == 0) return NULL;
+  *size = ls->size;
+  ls->size = 0;
+  return ls->s;
+}
+
+
+LUALIB_API int luaL_loadbufferx (lua_State *L, const char *buff, size_t size,
+                                 const char *name, const char *mode) {
+  LoadS ls;
+  ls.s = buff;
+  ls.size = size;
+  return lua_load(L, getS, &ls, name, mode);
+}
+
+
+LUALIB_API int luaL_loadstring (lua_State *L, const char *s) {
+  return luaL_loadbuffer(L, s, strlen(s), s);
+}
+
+/* }====================================================== */
+
+
+
+LUALIB_API int luaL_getmetafield (lua_State *L, int obj, const char *event) {
+  if (!lua_getmetatable(L, obj))  /* no metatable? */
+    return LUA_TNIL;
+  else {
+    int tt;
+    lua_pushstring(L, event);
+    tt = lua_rawget(L, -2);
+    if (tt == LUA_TNIL)  /* is metafield nil? */
+      lua_pop(L, 2);  /* remove metatable and metafield */
+    else
+      lua_remove(L, -2);  /* remove only metatable */
+    return tt;  /* return metafield type */
+  }
+}
+
+
+LUALIB_API int luaL_callmeta (lua_State *L, int obj, const char *event) {
+  obj = lua_absindex(L, obj);
+  if (luaL_getmetafield(L, obj, event) == LUA_TNIL)  /* no metafield? */
+    return 0;
+  lua_pushvalue(L, obj);
+  lua_call(L, 1, 1);
+  return 1;
+}
+
+
+LUALIB_API lua_Integer luaL_len (lua_State *L, int idx) {
+  lua_Integer l;
+  int isnum;
+  lua_len(L, idx);
+  l = lua_tointegerx(L, -1, &isnum);
+  if (!isnum)
+    luaL_error(L, "object length is not an integer");
+  lua_pop(L, 1);  /* remove object */
+  return l;
+}
+
+
+LUALIB_API const char *luaL_tolstring (lua_State *L, int idx, size_t *len) {
+  if (luaL_callmeta(L, idx, "__tostring")) {  /* metafield? */
+    if (!lua_isstring(L, -1))
+      luaL_error(L, "'__tostring' must return a string");
+  }
+  else {
+    switch (lua_type(L, idx)) {
+      case LUA_TNUMBER: {
+        if (lua_isinteger(L, idx))
+          lua_pushfstring(L, "%I", (LUAI_UACINT)lua_tointeger(L, idx));
+        else
+          lua_pushfstring(L, "%f", (LUAI_UACNUMBER)lua_tonumber(L, idx));
+        break;
+      }
+      case LUA_TSTRING:
+        lua_pushvalue(L, idx);
+        break;
+      case LUA_TBOOLEAN:
+        lua_pushstring(L, (lua_toboolean(L, idx) ? "true" : "false"));
+        break;
+      case LUA_TNIL:
+        lua_pushliteral(L, "nil");
+        break;
+      default: {
+        int tt = luaL_getmetafield(L, idx, "__name");  /* try name */
+        const char *kind = (tt == LUA_TSTRING) ? lua_tostring(L, -1) :
+                                                 luaL_typename(L, idx);
+        lua_pushfstring(L, "%s: %p", kind, lua_topointer(L, idx));
+        if (tt != LUA_TNIL)
+          lua_remove(L, -2);  /* remove '__name' */
+        break;
+      }
+    }
+  }
+  return lua_tolstring(L, -1, len);
+}
+
+
+/*
+** set functions from list 'l' into table at top - 'nup'; each
+** function gets the 'nup' elements at the top as upvalues.
+** Returns with only the table at the stack.
+*/
+LUALIB_API void luaL_setfuncs (lua_State *L, const luaL_Reg *l, int nup) {
+  luaL_checkstack(L, nup, "too many upvalues");
+  for (; l->name != NULL; l++) {  /* fill the table with given functions */
+    if (l->func == NULL)  /* place holder? */
+      lua_pushboolean(L, 0);
+    else {
+      int i;
+      for (i = 0; i < nup; i++)  /* copy upvalues to the top */
+        lua_pushvalue(L, -nup);
+      lua_pushcclosure(L, l->func, nup);  /* closure with those upvalues */
+    }
+    lua_setfield(L, -(nup + 2), l->name);
+  }
+  lua_pop(L, nup);  /* remove upvalues */
+}
+
+
+/*
+** ensure that stack[idx][fname] has a table and push that table
+** into the stack
+*/
+LUALIB_API int luaL_getsubtable (lua_State *L, int idx, const char *fname) {
+  if (lua_getfield(L, idx, fname) == LUA_TTABLE)
+    return 1;  /* table already there */
+  else {
+    lua_pop(L, 1);  /* remove previous result */
+    idx = lua_absindex(L, idx);
+    lua_newtable(L);
+    lua_pushvalue(L, -1);  /* copy to be left at top */
+    lua_setfield(L, idx, fname);  /* assign new table to field */
+    return 0;  /* false, because did not find table there */
+  }
+}
+
+
+/*
+** Stripped-down 'require': After checking "loaded" table, calls 'openf'
+** to open a module, registers the result in 'package.loaded' table and,
+** if 'glb' is true, also registers the result in the global table.
+** Leaves resulting module on the top.
+*/
+LUALIB_API void luaL_requiref (lua_State *L, const char *modname,
+                               lua_CFunction openf, int glb) {
+  luaL_getsubtable(L, LUA_REGISTRYINDEX, LUA_LOADED_TABLE);
+  lua_getfield(L, -1, modname);  /* LOADED[modname] */
+  if (!lua_toboolean(L, -1)) {  /* package not already loaded? */
+    lua_pop(L, 1);  /* remove field */
+    lua_pushcfunction(L, openf);
+    lua_pushstring(L, modname);  /* argument to open function */
+    lua_call(L, 1, 1);  /* call 'openf' to open module */
+    lua_pushvalue(L, -1);  /* make copy of module (call result) */
+    lua_setfield(L, -3, modname);  /* LOADED[modname] = module */
+  }
+  lua_remove(L, -2);  /* remove LOADED table */
+  if (glb) {
+    lua_pushvalue(L, -1);  /* copy of module */
+    lua_setglobal(L, modname);  /* _G[modname] = module */
+  }
+}
+
+
+LUALIB_API void luaL_addgsub (luaL_Buffer *b, const char *s,
+                                     const char *p, const char *r) {
+  const char *wild;
+  size_t l = strlen(p);
+  while ((wild = strstr(s, p)) != NULL) {
+    luaL_addlstring(b, s, wild - s);  /* push prefix */
+    luaL_addstring(b, r);  /* push replacement in place of pattern */
+    s = wild + l;  /* continue after 'p' */
+  }
+  luaL_addstring(b, s);  /* push last suffix */
+}
+
+
+LUALIB_API const char *luaL_gsub (lua_State *L, const char *s,
+                                  const char *p, const char *r) {
+  luaL_Buffer b;
+  luaL_buffinit(L, &b);
+  luaL_addgsub(&b, s, p, r);
+  luaL_pushresult(&b);
+  return lua_tostring(L, -1);
+}
+
+
+static void *l_alloc (void *ud, void *ptr, size_t osize, size_t nsize) {
+  (void)ud; (void)osize;  /* not used */
+  if (nsize == 0) {
+    free(ptr);
+    return NULL;
+  }
+  else
+    return realloc(ptr, nsize);
+}
+
+
+static int panic (lua_State *L) {
+  const char *msg = lua_tostring(L, -1);
+  if (msg == NULL) msg = "error object is not a string";
+  lua_writestringerror("PANIC: unprotected error in call to Lua API (%s)\n",
+                        msg);
+  return 0;  /* return to Lua to abort */
+}
+
+
+/*
+** Emit a warning. '*warnstate' means:
+** 0 - warning system is off;
+** 1 - ready to start a new message;
+** 2 - previous message is to be continued.
+*/
+static void warnf (void *ud, const char *message, int tocont) {
+  int *warnstate = (int *)ud;
+  if (*warnstate != 2 && !tocont && *message == '@') {  /* control message? */
+    if (strcmp(message, "@off") == 0)
+      *warnstate = 0;
+    else if (strcmp(message, "@on") == 0)
+      *warnstate = 1;
+    return;
+  }
+  else if (*warnstate == 0)  /* warnings off? */
+    return;
+  if (*warnstate == 1)  /* previous message was the last? */
+    lua_writestringerror("%s", "Lua warning: ");  /* start a new warning */
+  lua_writestringerror("%s", message);  /* write message */
+  if (tocont)  /* not the last part? */
+    *warnstate = 2;  /* to be continued */
+  else {  /* last part */
+    lua_writestringerror("%s", "\n");  /* finish message with end-of-line */
+    *warnstate = 1;  /* ready to start a new message */
+  }
+}
+
+
+LUALIB_API lua_State *luaL_newstate (void) {
+  lua_State *L = lua_newstate(l_alloc, NULL);
+  if (L) {
+    int *warnstate;  /* space for warning state */
+    lua_atpanic(L, &panic);
+    warnstate = (int *)lua_newuserdatauv(L, sizeof(int), 0);
+    luaL_ref(L, LUA_REGISTRYINDEX);  /* make sure it won't be collected */
+    *warnstate = 0;  /* default is warnings off */
+    lua_setwarnf(L, warnf, warnstate);
+  }
+  return L;
+}
+
+
+LUALIB_API void luaL_checkversion_ (lua_State *L, lua_Number ver, size_t sz) {
+  lua_Number v = lua_version(L);
+  if (sz != LUAL_NUMSIZES)  /* check numeric types */
+    luaL_error(L, "core and library have incompatible numeric types");
+  else if (v != ver)
+    luaL_error(L, "version mismatch: app. needs %f, Lua core provides %f",
+                  (LUAI_UACNUMBER)ver, (LUAI_UACNUMBER)v);
+}
+
diff --git a/test/external/lua-5.4.0/src/lauxlib.h b/test/external/lua-5.4.0/src/lauxlib.h
new file mode 100644
index 0000000..59fef6a
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lauxlib.h
@@ -0,0 +1,276 @@
+/*
+** $Id: lauxlib.h $
+** Auxiliary functions for building Lua libraries
+** See Copyright Notice in lua.h
+*/
+
+
+#ifndef lauxlib_h
+#define lauxlib_h
+
+
+#include <stddef.h>
+#include <stdio.h>
+
+#include "lua.h"
+
+
+/* global table */
+#define LUA_GNAME	"_G"
+
+
+typedef struct luaL_Buffer luaL_Buffer;
+
+
+/* extra error code for 'luaL_loadfilex' */
+#define LUA_ERRFILE     (LUA_ERRERR+1)
+
+
+/* key, in the registry, for table of loaded modules */
+#define LUA_LOADED_TABLE	"_LOADED"
+
+
+/* key, in the registry, for table of preloaded loaders */
+#define LUA_PRELOAD_TABLE	"_PRELOAD"
+
+
+typedef struct luaL_Reg {
+  const char *name;
+  lua_CFunction func;
+} luaL_Reg;
+
+
+#define LUAL_NUMSIZES	(sizeof(lua_Integer)*16 + sizeof(lua_Number))
+
+LUALIB_API void (luaL_checkversion_) (lua_State *L, lua_Number ver, size_t sz);
+#define luaL_checkversion(L)  \
+	  luaL_checkversion_(L, LUA_VERSION_NUM, LUAL_NUMSIZES)
+
+LUALIB_API int (luaL_getmetafield) (lua_State *L, int obj, const char *e);
+LUALIB_API int (luaL_callmeta) (lua_State *L, int obj, const char *e);
+LUALIB_API const char *(luaL_tolstring) (lua_State *L, int idx, size_t *len);
+LUALIB_API int (luaL_argerror) (lua_State *L, int arg, const char *extramsg);
+LUALIB_API int (luaL_typeerror) (lua_State *L, int arg, const char *tname);
+LUALIB_API const char *(luaL_checklstring) (lua_State *L, int arg,
+                                                          size_t *l);
+LUALIB_API const char *(luaL_optlstring) (lua_State *L, int arg,
+                                          const char *def, size_t *l);
+LUALIB_API lua_Number (luaL_checknumber) (lua_State *L, int arg);
+LUALIB_API lua_Number (luaL_optnumber) (lua_State *L, int arg, lua_Number def);
+
+LUALIB_API lua_Integer (luaL_checkinteger) (lua_State *L, int arg);
+LUALIB_API lua_Integer (luaL_optinteger) (lua_State *L, int arg,
+                                          lua_Integer def);
+
+LUALIB_API void (luaL_checkstack) (lua_State *L, int sz, const char *msg);
+LUALIB_API void (luaL_checktype) (lua_State *L, int arg, int t);
+LUALIB_API void (luaL_checkany) (lua_State *L, int arg);
+
+LUALIB_API int   (luaL_newmetatable) (lua_State *L, const char *tname);
+LUALIB_API void  (luaL_setmetatable) (lua_State *L, const char *tname);
+LUALIB_API void *(luaL_testudata) (lua_State *L, int ud, const char *tname);
+LUALIB_API void *(luaL_checkudata) (lua_State *L, int ud, const char *tname);
+
+LUALIB_API void (luaL_where) (lua_State *L, int lvl);
+LUALIB_API int (luaL_error) (lua_State *L, const char *fmt, ...);
+
+LUALIB_API int (luaL_checkoption) (lua_State *L, int arg, const char *def,
+                                   const char *const lst[]);
+
+LUALIB_API int (luaL_fileresult) (lua_State *L, int stat, const char *fname);
+LUALIB_API int (luaL_execresult) (lua_State *L, int stat);
+
+
+/* predefined references */
+#define LUA_NOREF       (-2)
+#define LUA_REFNIL      (-1)
+
+LUALIB_API int (luaL_ref) (lua_State *L, int t);
+LUALIB_API void (luaL_unref) (lua_State *L, int t, int ref);
+
+LUALIB_API int (luaL_loadfilex) (lua_State *L, const char *filename,
+                                               const char *mode);
+
+#define luaL_loadfile(L,f)	luaL_loadfilex(L,f,NULL)
+
+LUALIB_API int (luaL_loadbufferx) (lua_State *L, const char *buff, size_t sz,
+                                   const char *name, const char *mode);
+LUALIB_API int (luaL_loadstring) (lua_State *L, const char *s);
+
+LUALIB_API lua_State *(luaL_newstate) (void);
+
+LUALIB_API lua_Integer (luaL_len) (lua_State *L, int idx);
+
+LUALIB_API void luaL_addgsub (luaL_Buffer *b, const char *s,
+                                     const char *p, const char *r);
+LUALIB_API const char *(luaL_gsub) (lua_State *L, const char *s,
+                                    const char *p, const char *r);
+
+LUALIB_API void (luaL_setfuncs) (lua_State *L, const luaL_Reg *l, int nup);
+
+LUALIB_API int (luaL_getsubtable) (lua_State *L, int idx, const char *fname);
+
+LUALIB_API void (luaL_traceback) (lua_State *L, lua_State *L1,
+                                  const char *msg, int level);
+
+LUALIB_API void (luaL_requiref) (lua_State *L, const char *modname,
+                                 lua_CFunction openf, int glb);
+
+/*
+** ===============================================================
+** some useful macros
+** ===============================================================
+*/
+
+
+#define luaL_newlibtable(L,l)	\
+  lua_createtable(L, 0, sizeof(l)/sizeof((l)[0]) - 1)
+
+#define luaL_newlib(L,l)  \
+  (luaL_checkversion(L), luaL_newlibtable(L,l), luaL_setfuncs(L,l,0))
+
+#define luaL_argcheck(L, cond,arg,extramsg)	\
+		((void)((cond) || luaL_argerror(L, (arg), (extramsg))))
+
+#define luaL_argexpected(L,cond,arg,tname)	\
+		((void)((cond) || luaL_typeerror(L, (arg), (tname))))
+
+#define luaL_checkstring(L,n)	(luaL_checklstring(L, (n), NULL))
+#define luaL_optstring(L,n,d)	(luaL_optlstring(L, (n), (d), NULL))
+
+#define luaL_typename(L,i)	lua_typename(L, lua_type(L,(i)))
+
+#define luaL_dofile(L, fn) \
+	(luaL_loadfile(L, fn) || lua_pcall(L, 0, LUA_MULTRET, 0))
+
+#define luaL_dostring(L, s) \
+	(luaL_loadstring(L, s) || lua_pcall(L, 0, LUA_MULTRET, 0))
+
+#define luaL_getmetatable(L,n)	(lua_getfield(L, LUA_REGISTRYINDEX, (n)))
+
+#define luaL_opt(L,f,n,d)	(lua_isnoneornil(L,(n)) ? (d) : f(L,(n)))
+
+#define luaL_loadbuffer(L,s,sz,n)	luaL_loadbufferx(L,s,sz,n,NULL)
+
+
+/* push the value used to represent failure/error */
+#define luaL_pushfail(L)	lua_pushnil(L)
+
+
+/*
+** {======================================================
+** Generic Buffer manipulation
+** =======================================================
+*/
+
+struct luaL_Buffer {
+  char *b;  /* buffer address */
+  size_t size;  /* buffer size */
+  size_t n;  /* number of characters in buffer */
+  lua_State *L;
+  union {
+    LUAI_MAXALIGN;  /* ensure maximum alignment for buffer */
+    char b[LUAL_BUFFERSIZE];  /* initial buffer */
+  } init;
+};
+
+
+#define luaL_bufflen(bf)	((bf)->n)
+#define luaL_buffaddr(bf)	((bf)->b)
+
+
+#define luaL_addchar(B,c) \
+  ((void)((B)->n < (B)->size || luaL_prepbuffsize((B), 1)), \
+   ((B)->b[(B)->n++] = (c)))
+
+#define luaL_addsize(B,s)	((B)->n += (s))
+
+#define luaL_buffsub(B,s)	((B)->n -= (s))
+
+LUALIB_API void (luaL_buffinit) (lua_State *L, luaL_Buffer *B);
+LUALIB_API char *(luaL_prepbuffsize) (luaL_Buffer *B, size_t sz);
+LUALIB_API void (luaL_addlstring) (luaL_Buffer *B, const char *s, size_t l);
+LUALIB_API void (luaL_addstring) (luaL_Buffer *B, const char *s);
+LUALIB_API void (luaL_addvalue) (luaL_Buffer *B);
+LUALIB_API void (luaL_pushresult) (luaL_Buffer *B);
+LUALIB_API void (luaL_pushresultsize) (luaL_Buffer *B, size_t sz);
+LUALIB_API char *(luaL_buffinitsize) (lua_State *L, luaL_Buffer *B, size_t sz);
+
+#define luaL_prepbuffer(B)	luaL_prepbuffsize(B, LUAL_BUFFERSIZE)
+
+/* }====================================================== */
+
+
+
+/*
+** {======================================================
+** File handles for IO library
+** =======================================================
+*/
+
+/*
+** A file handle is a userdata with metatable 'LUA_FILEHANDLE' and
+** initial structure 'luaL_Stream' (it may contain other fields
+** after that initial structure).
+*/
+
+#define LUA_FILEHANDLE          "FILE*"
+
+
+typedef struct luaL_Stream {
+  FILE *f;  /* stream (NULL for incompletely created streams) */
+  lua_CFunction closef;  /* to close stream (NULL for closed streams) */
+} luaL_Stream;
+
+/* }====================================================== */
+
+/*
+** {==================================================================
+** "Abstraction Layer" for basic report of messages and errors
+** ===================================================================
+*/
+
+/* print a string */
+#if !defined(lua_writestring)
+#define lua_writestring(s,l)   fwrite((s), sizeof(char), (l), stdout)
+#endif
+
+/* print a newline and flush the output */
+#if !defined(lua_writeline)
+#define lua_writeline()        (lua_writestring("\n", 1), fflush(stdout))
+#endif
+
+/* print an error message */
+#if !defined(lua_writestringerror)
+#define lua_writestringerror(s,p) \
+        (fprintf(stderr, (s), (p)), fflush(stderr))
+#endif
+
+/* }================================================================== */
+
+
+/*
+** {============================================================
+** Compatibility with deprecated conversions
+** =============================================================
+*/
+#if defined(LUA_COMPAT_APIINTCASTS)
+
+#define luaL_checkunsigned(L,a)	((lua_Unsigned)luaL_checkinteger(L,a))
+#define luaL_optunsigned(L,a,d)	\
+	((lua_Unsigned)luaL_optinteger(L,a,(lua_Integer)(d)))
+
+#define luaL_checkint(L,n)	((int)luaL_checkinteger(L, (n)))
+#define luaL_optint(L,n,d)	((int)luaL_optinteger(L, (n), (d)))
+
+#define luaL_checklong(L,n)	((long)luaL_checkinteger(L, (n)))
+#define luaL_optlong(L,n,d)	((long)luaL_optinteger(L, (n), (d)))
+
+#endif
+/* }============================================================ */
+
+
+
+#endif
+
+
diff --git a/test/external/lua-5.4.0/src/lbaselib.c b/test/external/lua-5.4.0/src/lbaselib.c
new file mode 100644
index 0000000..747fd45
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lbaselib.c
@@ -0,0 +1,527 @@
+/*
+** $Id: lbaselib.c $
+** Basic library
+** See Copyright Notice in lua.h
+*/
+
+#define lbaselib_c
+#define LUA_LIB
+
+#include "lprefix.h"
+
+
+#include <ctype.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+static int luaB_print (lua_State *L) {
+  int n = lua_gettop(L);  /* number of arguments */
+  int i;
+  for (i = 1; i <= n; i++) {  /* for each argument */
+    size_t l;
+    const char *s = luaL_tolstring(L, i, &l);  /* convert it to string */
+    if (i > 1)  /* not the first element? */
+      lua_writestring("\t", 1);  /* add a tab before it */
+    lua_writestring(s, l);  /* print it */
+    lua_pop(L, 1);  /* pop result */
+  }
+  lua_writeline();
+  return 0;
+}
+
+
+/*
+** Creates a warning with all given arguments.
+** Check first for errors; otherwise an error may interrupt
+** the composition of a warning, leaving it unfinished.
+*/
+static int luaB_warn (lua_State *L) {
+  int n = lua_gettop(L);  /* number of arguments */
+  int i;
+  luaL_checkstring(L, 1);  /* at least one argument */
+  for (i = 2; i <= n; i++)
+    luaL_checkstring(L, i);  /* make sure all arguments are strings */
+  for (i = 1; i < n; i++)  /* compose warning */
+    lua_warning(L, lua_tostring(L, i), 1);
+  lua_warning(L, lua_tostring(L, n), 0);  /* close warning */
+  return 0;
+}
+
+
+#define SPACECHARS	" \f\n\r\t\v"
+
+static const char *b_str2int (const char *s, int base, lua_Integer *pn) {
+  lua_Unsigned n = 0;
+  int neg = 0;
+  s += strspn(s, SPACECHARS);  /* skip initial spaces */
+  if (*s == '-') { s++; neg = 1; }  /* handle sign */
+  else if (*s == '+') s++;
+  if (!isalnum((unsigned char)*s))  /* no digit? */
+    return NULL;
+  do {
+    int digit = (isdigit((unsigned char)*s)) ? *s - '0'
+                   : (toupper((unsigned char)*s) - 'A') + 10;
+    if (digit >= base) return NULL;  /* invalid numeral */
+    n = n * base + digit;
+    s++;
+  } while (isalnum((unsigned char)*s));
+  s += strspn(s, SPACECHARS);  /* skip trailing spaces */
+  *pn = (lua_Integer)((neg) ? (0u - n) : n);
+  return s;
+}
+
+
+static int luaB_tonumber (lua_State *L) {
+  if (lua_isnoneornil(L, 2)) {  /* standard conversion? */
+    if (lua_type(L, 1) == LUA_TNUMBER) {  /* already a number? */
+      lua_settop(L, 1);  /* yes; return it */
+      return 1;
+    }
+    else {
+      size_t l;
+      const char *s = lua_tolstring(L, 1, &l);
+      if (s != NULL && lua_stringtonumber(L, s) == l + 1)
+        return 1;  /* successful conversion to number */
+      /* else not a number */
+      luaL_checkany(L, 1);  /* (but there must be some parameter) */
+    }
+  }
+  else {
+    size_t l;
+    const char *s;
+    lua_Integer n = 0;  /* to avoid warnings */
+    lua_Integer base = luaL_checkinteger(L, 2);
+    luaL_checktype(L, 1, LUA_TSTRING);  /* no numbers as strings */
+    s = lua_tolstring(L, 1, &l);
+    luaL_argcheck(L, 2 <= base && base <= 36, 2, "base out of range");
+    if (b_str2int(s, (int)base, &n) == s + l) {
+      lua_pushinteger(L, n);
+      return 1;
+    }  /* else not a number */
+  }  /* else not a number */
+  luaL_pushfail(L);  /* not a number */
+  return 1;
+}
+
+
+static int luaB_error (lua_State *L) {
+  int level = (int)luaL_optinteger(L, 2, 1);
+  lua_settop(L, 1);
+  if (lua_type(L, 1) == LUA_TSTRING && level > 0) {
+    luaL_where(L, level);   /* add extra information */
+    lua_pushvalue(L, 1);
+    lua_concat(L, 2);
+  }
+  return lua_error(L);
+}
+
+
+static int luaB_getmetatable (lua_State *L) {
+  luaL_checkany(L, 1);
+  if (!lua_getmetatable(L, 1)) {
+    lua_pushnil(L);
+    return 1;  /* no metatable */
+  }
+  luaL_getmetafield(L, 1, "__metatable");
+  return 1;  /* returns either __metatable field (if present) or metatable */
+}
+
+
+static int luaB_setmetatable (lua_State *L) {
+  int t = lua_type(L, 2);
+  luaL_checktype(L, 1, LUA_TTABLE);
+  luaL_argexpected(L, t == LUA_TNIL || t == LUA_TTABLE, 2, "nil or table");
+  if (luaL_getmetafield(L, 1, "__metatable") != LUA_TNIL)
+    return luaL_error(L, "cannot change a protected metatable");
+  lua_settop(L, 2);
+  lua_setmetatable(L, 1);
+  return 1;
+}
+
+
+static int luaB_rawequal (lua_State *L) {
+  luaL_checkany(L, 1);
+  luaL_checkany(L, 2);
+  lua_pushboolean(L, lua_rawequal(L, 1, 2));
+  return 1;
+}
+
+
+static int luaB_rawlen (lua_State *L) {
+  int t = lua_type(L, 1);
+  luaL_argexpected(L, t == LUA_TTABLE || t == LUA_TSTRING, 1,
+                      "table or string");
+  lua_pushinteger(L, lua_rawlen(L, 1));
+  return 1;
+}
+
+
+static int luaB_rawget (lua_State *L) {
+  luaL_checktype(L, 1, LUA_TTABLE);
+  luaL_checkany(L, 2);
+  lua_settop(L, 2);
+  lua_rawget(L, 1);
+  return 1;
+}
+
+static int luaB_rawset (lua_State *L) {
+  luaL_checktype(L, 1, LUA_TTABLE);
+  luaL_checkany(L, 2);
+  luaL_checkany(L, 3);
+  lua_settop(L, 3);
+  lua_rawset(L, 1);
+  return 1;
+}
+
+
+static int pushmode (lua_State *L, int oldmode) {
+  lua_pushstring(L, (oldmode == LUA_GCINC) ? "incremental" : "generational");
+  return 1;
+}
+
+
+static int luaB_collectgarbage (lua_State *L) {
+  static const char *const opts[] = {"stop", "restart", "collect",
+    "count", "step", "setpause", "setstepmul",
+    "isrunning", "generational", "incremental", NULL};
+  static const int optsnum[] = {LUA_GCSTOP, LUA_GCRESTART, LUA_GCCOLLECT,
+    LUA_GCCOUNT, LUA_GCSTEP, LUA_GCSETPAUSE, LUA_GCSETSTEPMUL,
+    LUA_GCISRUNNING, LUA_GCGEN, LUA_GCINC};
+  int o = optsnum[luaL_checkoption(L, 1, "collect", opts)];
+  switch (o) {
+    case LUA_GCCOUNT: {
+      int k = lua_gc(L, o);
+      int b = lua_gc(L, LUA_GCCOUNTB);
+      lua_pushnumber(L, (lua_Number)k + ((lua_Number)b/1024));
+      return 1;
+    }
+    case LUA_GCSTEP: {
+      int step = (int)luaL_optinteger(L, 2, 0);
+      int res = lua_gc(L, o, step);
+      lua_pushboolean(L, res);
+      return 1;
+    }
+    case LUA_GCSETPAUSE:
+    case LUA_GCSETSTEPMUL: {
+      int p = (int)luaL_optinteger(L, 2, 0);
+      int previous = lua_gc(L, o, p);
+      lua_pushinteger(L, previous);
+      return 1;
+    }
+    case LUA_GCISRUNNING: {
+      int res = lua_gc(L, o);
+      lua_pushboolean(L, res);
+      return 1;
+    }
+    case LUA_GCGEN: {
+      int minormul = (int)luaL_optinteger(L, 2, 0);
+      int majormul = (int)luaL_optinteger(L, 3, 0);
+      return pushmode(L, lua_gc(L, o, minormul, majormul));
+    }
+    case LUA_GCINC: {
+      int pause = (int)luaL_optinteger(L, 2, 0);
+      int stepmul = (int)luaL_optinteger(L, 3, 0);
+      int stepsize = (int)luaL_optinteger(L, 4, 0);
+      return pushmode(L, lua_gc(L, o, pause, stepmul, stepsize));
+    }
+    default: {
+      int res = lua_gc(L, o);
+      lua_pushinteger(L, res);
+      return 1;
+    }
+  }
+}
+
+
+static int luaB_type (lua_State *L) {
+  int t = lua_type(L, 1);
+  luaL_argcheck(L, t != LUA_TNONE, 1, "value expected");
+  lua_pushstring(L, lua_typename(L, t));
+  return 1;
+}
+
+
+static int luaB_next (lua_State *L) {
+  luaL_checktype(L, 1, LUA_TTABLE);
+  lua_settop(L, 2);  /* create a 2nd argument if there isn't one */
+  if (lua_next(L, 1))
+    return 2;
+  else {
+    lua_pushnil(L);
+    return 1;
+  }
+}
+
+
+static int luaB_pairs (lua_State *L) {
+  luaL_checkany(L, 1);
+  if (luaL_getmetafield(L, 1, "__pairs") == LUA_TNIL) {  /* no metamethod? */
+    lua_pushcfunction(L, luaB_next);  /* will return generator, */
+    lua_pushvalue(L, 1);  /* state, */
+    lua_pushnil(L);  /* and initial value */
+  }
+  else {
+    lua_pushvalue(L, 1);  /* argument 'self' to metamethod */
+    lua_call(L, 1, 3);  /* get 3 values from metamethod */
+  }
+  return 3;
+}
+
+
+/*
+** Traversal function for 'ipairs'
+*/
+static int ipairsaux (lua_State *L) {
+  lua_Integer i = luaL_checkinteger(L, 2) + 1;
+  lua_pushinteger(L, i);
+  return (lua_geti(L, 1, i) == LUA_TNIL) ? 1 : 2;
+}
+
+
+/*
+** 'ipairs' function. Returns 'ipairsaux', given "table", 0.
+** (The given "table" may not be a table.)
+*/
+static int luaB_ipairs (lua_State *L) {
+  luaL_checkany(L, 1);
+  lua_pushcfunction(L, ipairsaux);  /* iteration function */
+  lua_pushvalue(L, 1);  /* state */
+  lua_pushinteger(L, 0);  /* initial value */
+  return 3;
+}
+
+
+static int load_aux (lua_State *L, int status, int envidx) {
+  if (status == LUA_OK) {
+    if (envidx != 0) {  /* 'env' parameter? */
+      lua_pushvalue(L, envidx);  /* environment for loaded function */
+      if (!lua_setupvalue(L, -2, 1))  /* set it as 1st upvalue */
+        lua_pop(L, 1);  /* remove 'env' if not used by previous call */
+    }
+    return 1;
+  }
+  else {  /* error (message is on top of the stack) */
+    luaL_pushfail(L);
+    lua_insert(L, -2);  /* put before error message */
+    return 2;  /* return fail plus error message */
+  }
+}
+
+
+static int luaB_loadfile (lua_State *L) {
+  const char *fname = luaL_optstring(L, 1, NULL);
+  const char *mode = luaL_optstring(L, 2, NULL);
+  int env = (!lua_isnone(L, 3) ? 3 : 0);  /* 'env' index or 0 if no 'env' */
+  int status = luaL_loadfilex(L, fname, mode);
+  return load_aux(L, status, env);
+}
+
+
+/*
+** {======================================================
+** Generic Read function
+** =======================================================
+*/
+
+
+/*
+** reserved slot, above all arguments, to hold a copy of the returned
+** string to avoid it being collected while parsed. 'load' has four
+** optional arguments (chunk, source name, mode, and environment).
+*/
+#define RESERVEDSLOT	5
+
+
+/*
+** Reader for generic 'load' function: 'lua_load' uses the
+** stack for internal stuff, so the reader cannot change the
+** stack top. Instead, it keeps its resulting string in a
+** reserved slot inside the stack.
+*/
+static const char *generic_reader (lua_State *L, void *ud, size_t *size) {
+  (void)(ud);  /* not used */
+  luaL_checkstack(L, 2, "too many nested functions");
+  lua_pushvalue(L, 1);  /* get function */
+  lua_call(L, 0, 1);  /* call it */
+  if (lua_isnil(L, -1)) {
+    lua_pop(L, 1);  /* pop result */
+    *size = 0;
+    return NULL;
+  }
+  else if (!lua_isstring(L, -1))
+    luaL_error(L, "reader function must return a string");
+  lua_replace(L, RESERVEDSLOT);  /* save string in reserved slot */
+  return lua_tolstring(L, RESERVEDSLOT, size);
+}
+
+
+static int luaB_load (lua_State *L) {
+  int status;
+  size_t l;
+  const char *s = lua_tolstring(L, 1, &l);
+  const char *mode = luaL_optstring(L, 3, "bt");
+  int env = (!lua_isnone(L, 4) ? 4 : 0);  /* 'env' index or 0 if no 'env' */
+  if (s != NULL) {  /* loading a string? */
+    const char *chunkname = luaL_optstring(L, 2, s);
+    status = luaL_loadbufferx(L, s, l, chunkname, mode);
+  }
+  else {  /* loading from a reader function */
+    const char *chunkname = luaL_optstring(L, 2, "=(load)");
+    luaL_checktype(L, 1, LUA_TFUNCTION);
+    lua_settop(L, RESERVEDSLOT);  /* create reserved slot */
+    status = lua_load(L, generic_reader, NULL, chunkname, mode);
+  }
+  return load_aux(L, status, env);
+}
+
+/* }====================================================== */
+
+
+static int dofilecont (lua_State *L, int d1, lua_KContext d2) {
+  (void)d1;  (void)d2;  /* only to match 'lua_Kfunction' prototype */
+  return lua_gettop(L) - 1;
+}
+
+
+static int luaB_dofile (lua_State *L) {
+  const char *fname = luaL_optstring(L, 1, NULL);
+  lua_settop(L, 1);
+  if (luaL_loadfile(L, fname) != LUA_OK)
+    return lua_error(L);
+  lua_callk(L, 0, LUA_MULTRET, 0, dofilecont);
+  return dofilecont(L, 0, 0);
+}
+
+
+static int luaB_assert (lua_State *L) {
+  if (lua_toboolean(L, 1))  /* condition is true? */
+    return lua_gettop(L);  /* return all arguments */
+  else {  /* error */
+    luaL_checkany(L, 1);  /* there must be a condition */
+    lua_remove(L, 1);  /* remove it */
+    lua_pushliteral(L, "assertion failed!");  /* default message */
+    lua_settop(L, 1);  /* leave only message (default if no other one) */
+    return luaB_error(L);  /* call 'error' */
+  }
+}
+
+
+static int luaB_select (lua_State *L) {
+  int n = lua_gettop(L);
+  if (lua_type(L, 1) == LUA_TSTRING && *lua_tostring(L, 1) == '#') {
+    lua_pushinteger(L, n-1);
+    return 1;
+  }
+  else {
+    lua_Integer i = luaL_checkinteger(L, 1);
+    if (i < 0) i = n + i;
+    else if (i > n) i = n;
+    luaL_argcheck(L, 1 <= i, 1, "index out of range");
+    return n - (int)i;
+  }
+}
+
+
+/*
+** Continuation function for 'pcall' and 'xpcall'. Both functions
+** already pushed a 'true' before doing the call, so in case of success
+** 'finishpcall' only has to return everything in the stack minus
+** 'extra' values (where 'extra' is exactly the number of items to be
+** ignored).
+*/
+static int finishpcall (lua_State *L, int status, lua_KContext extra) {
+  if (status != LUA_OK && status != LUA_YIELD) {  /* error? */
+    lua_pushboolean(L, 0);  /* first result (false) */
+    lua_pushvalue(L, -2);  /* error message */
+    return 2;  /* return false, msg */
+  }
+  else
+    return lua_gettop(L) - (int)extra;  /* return all results */
+}
+
+
+static int luaB_pcall (lua_State *L) {
+  int status;
+  luaL_checkany(L, 1);
+  lua_pushboolean(L, 1);  /* first result if no errors */
+  lua_insert(L, 1);  /* put it in place */
+  status = lua_pcallk(L, lua_gettop(L) - 2, LUA_MULTRET, 0, 0, finishpcall);
+  return finishpcall(L, status, 0);
+}
+
+
+/*
+** Do a protected call with error handling. After 'lua_rotate', the
+** stack will have <f, err, true, f, [args...]>; so, the function passes
+** 2 to 'finishpcall' to skip the 2 first values when returning results.
+*/
+static int luaB_xpcall (lua_State *L) {
+  int status;
+  int n = lua_gettop(L);
+  luaL_checktype(L, 2, LUA_TFUNCTION);  /* check error function */
+  lua_pushboolean(L, 1);  /* first result */
+  lua_pushvalue(L, 1);  /* function */
+  lua_rotate(L, 3, 2);  /* move them below function's arguments */
+  status = lua_pcallk(L, n - 2, LUA_MULTRET, 2, 2, finishpcall);
+  return finishpcall(L, status, 2);
+}
+
+
+static int luaB_tostring (lua_State *L) {
+  luaL_checkany(L, 1);
+  luaL_tolstring(L, 1, NULL);
+  return 1;
+}
+
+
+static const luaL_Reg base_funcs[] = {
+  {"assert", luaB_assert},
+  {"collectgarbage", luaB_collectgarbage},
+  {"dofile", luaB_dofile},
+  {"error", luaB_error},
+  {"getmetatable", luaB_getmetatable},
+  {"ipairs", luaB_ipairs},
+  {"loadfile", luaB_loadfile},
+  {"load", luaB_load},
+  {"next", luaB_next},
+  {"pairs", luaB_pairs},
+  {"pcall", luaB_pcall},
+  {"print", luaB_print},
+  {"warn", luaB_warn},
+  {"rawequal", luaB_rawequal},
+  {"rawlen", luaB_rawlen},
+  {"rawget", luaB_rawget},
+  {"rawset", luaB_rawset},
+  {"select", luaB_select},
+  {"setmetatable", luaB_setmetatable},
+  {"tonumber", luaB_tonumber},
+  {"tostring", luaB_tostring},
+  {"type", luaB_type},
+  {"xpcall", luaB_xpcall},
+  /* placeholders */
+  {LUA_GNAME, NULL},
+  {"_VERSION", NULL},
+  {NULL, NULL}
+};
+
+
+LUAMOD_API int luaopen_base (lua_State *L) {
+  /* open lib into global table */
+  lua_pushglobaltable(L);
+  luaL_setfuncs(L, base_funcs, 0);
+  /* set global _G */
+  lua_pushvalue(L, -1);
+  lua_setfield(L, -2, LUA_GNAME);
+  /* set global _VERSION */
+  lua_pushliteral(L, LUA_VERSION);
+  lua_setfield(L, -2, "_VERSION");
+  return 1;
+}
+
diff --git a/test/external/lua-5.4.0/src/lcode.c b/test/external/lua-5.4.0/src/lcode.c
new file mode 100644
index 0000000..6f241c9
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lcode.c
@@ -0,0 +1,1814 @@
+/*
+** $Id: lcode.c $
+** Code generator for Lua
+** See Copyright Notice in lua.h
+*/
+
+#define lcode_c
+#define LUA_CORE
+
+#include "lprefix.h"
+
+
+#include <limits.h>
+#include <math.h>
+#include <stdlib.h>
+
+#include "lua.h"
+
+#include "lcode.h"
+#include "ldebug.h"
+#include "ldo.h"
+#include "lgc.h"
+#include "llex.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lopcodes.h"
+#include "lparser.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "lvm.h"
+
+
+/* Maximum number of registers in a Lua function (must fit in 8 bits) */
+#define MAXREGS		255
+
+
+#define hasjumps(e)	((e)->t != (e)->f)
+
+
+static int codesJ (FuncState *fs, OpCode o, int sj, int k);
+
+
+
+/* semantic error */
+l_noret luaK_semerror (LexState *ls, const char *msg) {
+  ls->t.token = 0;  /* remove "near <token>" from final message */
+  luaX_syntaxerror(ls, msg);
+}
+
+
+/*
+** If expression is a numeric constant, fills 'v' with its value
+** and returns 1. Otherwise, returns 0.
+*/
+static int tonumeral (const expdesc *e, TValue *v) {
+  if (hasjumps(e))
+    return 0;  /* not a numeral */
+  switch (e->k) {
+    case VKINT:
+      if (v) setivalue(v, e->u.ival);
+      return 1;
+    case VKFLT:
+      if (v) setfltvalue(v, e->u.nval);
+      return 1;
+    default: return 0;
+  }
+}
+
+
+/*
+** Get the constant value from a constant expression
+*/
+static TValue *const2val (FuncState *fs, const expdesc *e) {
+  lua_assert(e->k == VCONST);
+  return &fs->ls->dyd->actvar.arr[e->u.info].k;
+}
+
+
+/*
+** If expression is a constant, fills 'v' with its value
+** and returns 1. Otherwise, returns 0.
+*/
+int luaK_exp2const (FuncState *fs, const expdesc *e, TValue *v) {
+  if (hasjumps(e))
+    return 0;  /* not a constant */
+  switch (e->k) {
+    case VFALSE:
+      setbfvalue(v);
+      return 1;
+    case VTRUE:
+      setbtvalue(v);
+      return 1;
+    case VNIL:
+      setnilvalue(v);
+      return 1;
+    case VKSTR: {
+      setsvalue(fs->ls->L, v, e->u.strval);
+      return 1;
+    }
+    case VCONST: {
+      setobj(fs->ls->L, v, const2val(fs, e));
+      return 1;
+    }
+    default: return tonumeral(e, v);
+  }
+}
+
+
+/*
+** Return the previous instruction of the current code. If there
+** may be a jump target between the current instruction and the
+** previous one, return an invalid instruction (to avoid wrong
+** optimizations).
+*/
+static Instruction *previousinstruction (FuncState *fs) {
+  static const Instruction invalidinstruction = ~(Instruction)0;
+  if (fs->pc > fs->lasttarget)
+    return &fs->f->code[fs->pc - 1];  /* previous instruction */
+  else
+    return cast(Instruction*, &invalidinstruction);
+}
+
+
+/*
+** Create a OP_LOADNIL instruction, but try to optimize: if the previous
+** instruction is also OP_LOADNIL and ranges are compatible, adjust
+** range of previous instruction instead of emitting a new one. (For
+** instance, 'local a; local b' will generate a single opcode.)
+*/
+void luaK_nil (FuncState *fs, int from, int n) {
+  int l = from + n - 1;  /* last register to set nil */
+  Instruction *previous = previousinstruction(fs);
+  if (GET_OPCODE(*previous) == OP_LOADNIL) {  /* previous is LOADNIL? */
+    int pfrom = GETARG_A(*previous);  /* get previous range */
+    int pl = pfrom + GETARG_B(*previous);
+    if ((pfrom <= from && from <= pl + 1) ||
+        (from <= pfrom && pfrom <= l + 1)) {  /* can connect both? */
+      if (pfrom < from) from = pfrom;  /* from = min(from, pfrom) */
+      if (pl > l) l = pl;  /* l = max(l, pl) */
+      SETARG_A(*previous, from);
+      SETARG_B(*previous, l - from);
+      return;
+    }  /* else go through */
+  }
+  luaK_codeABC(fs, OP_LOADNIL, from, n - 1, 0);  /* else no optimization */
+}
+
+
+/*
+** Gets the destination address of a jump instruction. Used to traverse
+** a list of jumps.
+*/
+static int getjump (FuncState *fs, int pc) {
+  int offset = GETARG_sJ(fs->f->code[pc]);
+  if (offset == NO_JUMP)  /* point to itself represents end of list */
+    return NO_JUMP;  /* end of list */
+  else
+    return (pc+1)+offset;  /* turn offset into absolute position */
+}
+
+
+/*
+** Fix jump instruction at position 'pc' to jump to 'dest'.
+** (Jump addresses are relative in Lua)
+*/
+static void fixjump (FuncState *fs, int pc, int dest) {
+  Instruction *jmp = &fs->f->code[pc];
+  int offset = dest - (pc + 1);
+  lua_assert(dest != NO_JUMP);
+  if (!(-OFFSET_sJ <= offset && offset <= MAXARG_sJ - OFFSET_sJ))
+    luaX_syntaxerror(fs->ls, "control structure too long");
+  lua_assert(GET_OPCODE(*jmp) == OP_JMP);
+  SETARG_sJ(*jmp, offset);
+}
+
+
+/*
+** Concatenate jump-list 'l2' into jump-list 'l1'
+*/
+void luaK_concat (FuncState *fs, int *l1, int l2) {
+  if (l2 == NO_JUMP) return;  /* nothing to concatenate? */
+  else if (*l1 == NO_JUMP)  /* no original list? */
+    *l1 = l2;  /* 'l1' points to 'l2' */
+  else {
+    int list = *l1;
+    int next;
+    while ((next = getjump(fs, list)) != NO_JUMP)  /* find last element */
+      list = next;
+    fixjump(fs, list, l2);  /* last element links to 'l2' */
+  }
+}
+
+
+/*
+** Create a jump instruction and return its position, so its destination
+** can be fixed later (with 'fixjump').
+*/
+int luaK_jump (FuncState *fs) {
+  return codesJ(fs, OP_JMP, NO_JUMP, 0);
+}
+
+
+/*
+** Code a 'return' instruction
+*/
+void luaK_ret (FuncState *fs, int first, int nret) {
+  OpCode op;
+  switch (nret) {
+    case 0: op = OP_RETURN0; break;
+    case 1: op = OP_RETURN1; break;
+    default: op = OP_RETURN; break;
+  }
+  luaK_codeABC(fs, op, first, nret + 1, 0);
+}
+
+
+/*
+** Code a "conditional jump", that is, a test or comparison opcode
+** followed by a jump. Return jump position.
+*/
+static int condjump (FuncState *fs, OpCode op, int A, int B, int C, int k) {
+  luaK_codeABCk(fs, op, A, B, C, k);
+  return luaK_jump(fs);
+}
+
+
+/*
+** returns current 'pc' and marks it as a jump target (to avoid wrong
+** optimizations with consecutive instructions not in the same basic block).
+*/
+int luaK_getlabel (FuncState *fs) {
+  fs->lasttarget = fs->pc;
+  return fs->pc;
+}
+
+
+/*
+** Returns the position of the instruction "controlling" a given
+** jump (that is, its condition), or the jump itself if it is
+** unconditional.
+*/
+static Instruction *getjumpcontrol (FuncState *fs, int pc) {
+  Instruction *pi = &fs->f->code[pc];
+  if (pc >= 1 && testTMode(GET_OPCODE(*(pi-1))))
+    return pi-1;
+  else
+    return pi;
+}
+
+
+/*
+** Patch destination register for a TESTSET instruction.
+** If instruction in position 'node' is not a TESTSET, return 0 ("fails").
+** Otherwise, if 'reg' is not 'NO_REG', set it as the destination
+** register. Otherwise, change instruction to a simple 'TEST' (produces
+** no register value)
+*/
+static int patchtestreg (FuncState *fs, int node, int reg) {
+  Instruction *i = getjumpcontrol(fs, node);
+  if (GET_OPCODE(*i) != OP_TESTSET)
+    return 0;  /* cannot patch other instructions */
+  if (reg != NO_REG && reg != GETARG_B(*i))
+    SETARG_A(*i, reg);
+  else {
+     /* no register to put value or register already has the value;
+        change instruction to simple test */
+    *i = CREATE_ABCk(OP_TEST, GETARG_B(*i), 0, 0, GETARG_k(*i));
+  }
+  return 1;
+}
+
+
+/*
+** Traverse a list of tests ensuring no one produces a value
+*/
+static void removevalues (FuncState *fs, int list) {
+  for (; list != NO_JUMP; list = getjump(fs, list))
+      patchtestreg(fs, list, NO_REG);
+}
+
+
+/*
+** Traverse a list of tests, patching their destination address and
+** registers: tests producing values jump to 'vtarget' (and put their
+** values in 'reg'), other tests jump to 'dtarget'.
+*/
+static void patchlistaux (FuncState *fs, int list, int vtarget, int reg,
+                          int dtarget) {
+  while (list != NO_JUMP) {
+    int next = getjump(fs, list);
+    if (patchtestreg(fs, list, reg))
+      fixjump(fs, list, vtarget);
+    else
+      fixjump(fs, list, dtarget);  /* jump to default target */
+    list = next;
+  }
+}
+
+
+/*
+** Path all jumps in 'list' to jump to 'target'.
+** (The assert means that we cannot fix a jump to a forward address
+** because we only know addresses once code is generated.)
+*/
+void luaK_patchlist (FuncState *fs, int list, int target) {
+  lua_assert(target <= fs->pc);
+  patchlistaux(fs, list, target, NO_REG, target);
+}
+
+
+void luaK_patchtohere (FuncState *fs, int list) {
+  int hr = luaK_getlabel(fs);  /* mark "here" as a jump target */
+  luaK_patchlist(fs, list, hr);
+}
+
+
+/*
+** MAXimum number of successive Instructions WiTHout ABSolute line
+** information.
+*/
+#if !defined(MAXIWTHABS)
+#define MAXIWTHABS	120
+#endif
+
+
+/* limit for difference between lines in relative line info. */
+#define LIMLINEDIFF	0x80
+
+
+/*
+** Save line info for a new instruction. If difference from last line
+** does not fit in a byte, of after that many instructions, save a new
+** absolute line info; (in that case, the special value 'ABSLINEINFO'
+** in 'lineinfo' signals the existence of this absolute information.)
+** Otherwise, store the difference from last line in 'lineinfo'.
+*/
+static void savelineinfo (FuncState *fs, Proto *f, int line) {
+  int linedif = line - fs->previousline;
+  int pc = fs->pc - 1;  /* last instruction coded */
+  if (abs(linedif) >= LIMLINEDIFF || fs->iwthabs++ > MAXIWTHABS) {
+    luaM_growvector(fs->ls->L, f->abslineinfo, fs->nabslineinfo,
+                    f->sizeabslineinfo, AbsLineInfo, MAX_INT, "lines");
+    f->abslineinfo[fs->nabslineinfo].pc = pc;
+    f->abslineinfo[fs->nabslineinfo++].line = line;
+    linedif = ABSLINEINFO;  /* signal that there is absolute information */
+    fs->iwthabs = 0;  /* restart counter */
+  }
+  luaM_growvector(fs->ls->L, f->lineinfo, pc, f->sizelineinfo, ls_byte,
+                  MAX_INT, "opcodes");
+  f->lineinfo[pc] = linedif;
+  fs->previousline = line;  /* last line saved */
+}
+
+
+/*
+** Remove line information from the last instruction.
+** If line information for that instruction is absolute, set 'iwthabs'
+** above its max to force the new (replacing) instruction to have
+** absolute line info, too.
+*/
+static void removelastlineinfo (FuncState *fs) {
+  Proto *f = fs->f;
+  int pc = fs->pc - 1;  /* last instruction coded */
+  if (f->lineinfo[pc] != ABSLINEINFO) {  /* relative line info? */
+    fs->previousline -= f->lineinfo[pc];  /* correct last line saved */
+    fs->iwthabs--;  /* undo previous increment */
+  }
+  else {  /* absolute line information */
+    lua_assert(f->abslineinfo[fs->nabslineinfo - 1].pc == pc);
+    fs->nabslineinfo--;  /* remove it */
+    fs->iwthabs = MAXIWTHABS + 1;  /* force next line info to be absolute */
+  }
+}
+
+
+/*
+** Remove the last instruction created, correcting line information
+** accordingly.
+*/
+static void removelastinstruction (FuncState *fs) {
+  removelastlineinfo(fs);
+  fs->pc--;
+}
+
+
+/*
+** Emit instruction 'i', checking for array sizes and saving also its
+** line information. Return 'i' position.
+*/
+int luaK_code (FuncState *fs, Instruction i) {
+  Proto *f = fs->f;
+  /* put new instruction in code array */
+  luaM_growvector(fs->ls->L, f->code, fs->pc, f->sizecode, Instruction,
+                  MAX_INT, "opcodes");
+  f->code[fs->pc++] = i;
+  savelineinfo(fs, f, fs->ls->lastline);
+  return fs->pc - 1;  /* index of new instruction */
+}
+
+
+/*
+** Format and emit an 'iABC' instruction. (Assertions check consistency
+** of parameters versus opcode.)
+*/
+int luaK_codeABCk (FuncState *fs, OpCode o, int a, int b, int c, int k) {
+  lua_assert(getOpMode(o) == iABC);
+  lua_assert(a <= MAXARG_A && b <= MAXARG_B &&
+             c <= MAXARG_C && (k & ~1) == 0);
+  return luaK_code(fs, CREATE_ABCk(o, a, b, c, k));
+}
+
+
+/*
+** Format and emit an 'iABx' instruction.
+*/
+int luaK_codeABx (FuncState *fs, OpCode o, int a, unsigned int bc) {
+  lua_assert(getOpMode(o) == iABx);
+  lua_assert(a <= MAXARG_A && bc <= MAXARG_Bx);
+  return luaK_code(fs, CREATE_ABx(o, a, bc));
+}
+
+
+/*
+** Format and emit an 'iAsBx' instruction.
+*/
+int luaK_codeAsBx (FuncState *fs, OpCode o, int a, int bc) {
+  unsigned int b = bc + OFFSET_sBx;
+  lua_assert(getOpMode(o) == iAsBx);
+  lua_assert(a <= MAXARG_A && b <= MAXARG_Bx);
+  return luaK_code(fs, CREATE_ABx(o, a, b));
+}
+
+
+/*
+** Format and emit an 'isJ' instruction.
+*/
+static int codesJ (FuncState *fs, OpCode o, int sj, int k) {
+  unsigned int j = sj + OFFSET_sJ;
+  lua_assert(getOpMode(o) == isJ);
+  lua_assert(j <= MAXARG_sJ && (k & ~1) == 0);
+  return luaK_code(fs, CREATE_sJ(o, j, k));
+}
+
+
+/*
+** Emit an "extra argument" instruction (format 'iAx')
+*/
+static int codeextraarg (FuncState *fs, int a) {
+  lua_assert(a <= MAXARG_Ax);
+  return luaK_code(fs, CREATE_Ax(OP_EXTRAARG, a));
+}
+
+
+/*
+** Emit a "load constant" instruction, using either 'OP_LOADK'
+** (if constant index 'k' fits in 18 bits) or an 'OP_LOADKX'
+** instruction with "extra argument".
+*/
+static int luaK_codek (FuncState *fs, int reg, int k) {
+  if (k <= MAXARG_Bx)
+    return luaK_codeABx(fs, OP_LOADK, reg, k);
+  else {
+    int p = luaK_codeABx(fs, OP_LOADKX, reg, 0);
+    codeextraarg(fs, k);
+    return p;
+  }
+}
+
+
+/*
+** Check register-stack level, keeping track of its maximum size
+** in field 'maxstacksize'
+*/
+void luaK_checkstack (FuncState *fs, int n) {
+  int newstack = fs->freereg + n;
+  if (newstack > fs->f->maxstacksize) {
+    if (newstack >= MAXREGS)
+      luaX_syntaxerror(fs->ls,
+        "function or expression needs too many registers");
+    fs->f->maxstacksize = cast_byte(newstack);
+  }
+}
+
+
+/*
+** Reserve 'n' registers in register stack
+*/
+void luaK_reserveregs (FuncState *fs, int n) {
+  luaK_checkstack(fs, n);
+  fs->freereg += n;
+}
+
+
+/*
+** Free register 'reg', if it is neither a constant index nor
+** a local variable.
+)
+*/
+static void freereg (FuncState *fs, int reg) {
+  if (reg >= luaY_nvarstack(fs)) {
+    fs->freereg--;
+    lua_assert(reg == fs->freereg);
+  }
+}
+
+
+/*
+** Free two registers in proper order
+*/
+static void freeregs (FuncState *fs, int r1, int r2) {
+  if (r1 > r2) {
+    freereg(fs, r1);
+    freereg(fs, r2);
+  }
+  else {
+    freereg(fs, r2);
+    freereg(fs, r1);
+  }
+}
+
+
+/*
+** Free register used by expression 'e' (if any)
+*/
+static void freeexp (FuncState *fs, expdesc *e) {
+  if (e->k == VNONRELOC)
+    freereg(fs, e->u.info);
+}
+
+
+/*
+** Free registers used by expressions 'e1' and 'e2' (if any) in proper
+** order.
+*/
+static void freeexps (FuncState *fs, expdesc *e1, expdesc *e2) {
+  int r1 = (e1->k == VNONRELOC) ? e1->u.info : -1;
+  int r2 = (e2->k == VNONRELOC) ? e2->u.info : -1;
+  freeregs(fs, r1, r2);
+}
+
+
+/*
+** Add constant 'v' to prototype's list of constants (field 'k').
+** Use scanner's table to cache position of constants in constant list
+** and try to reuse constants. Because some values should not be used
+** as keys (nil cannot be a key, integer keys can collapse with float
+** keys), the caller must provide a useful 'key' for indexing the cache.
+*/
+static int addk (FuncState *fs, TValue *key, TValue *v) {
+  lua_State *L = fs->ls->L;
+  Proto *f = fs->f;
+  TValue *idx = luaH_set(L, fs->ls->h, key);  /* index scanner table */
+  int k, oldsize;
+  if (ttisinteger(idx)) {  /* is there an index there? */
+    k = cast_int(ivalue(idx));
+    /* correct value? (warning: must distinguish floats from integers!) */
+    if (k < fs->nk && ttypetag(&f->k[k]) == ttypetag(v) &&
+                      luaV_rawequalobj(&f->k[k], v))
+      return k;  /* reuse index */
+  }
+  /* constant not found; create a new entry */
+  oldsize = f->sizek;
+  k = fs->nk;
+  /* numerical value does not need GC barrier;
+     table has no metatable, so it does not need to invalidate cache */
+  setivalue(idx, k);
+  luaM_growvector(L, f->k, k, f->sizek, TValue, MAXARG_Ax, "constants");
+  while (oldsize < f->sizek) setnilvalue(&f->k[oldsize++]);
+  setobj(L, &f->k[k], v);
+  fs->nk++;
+  luaC_barrier(L, f, v);
+  return k;
+}
+
+
+/*
+** Add a string to list of constants and return its index.
+*/
+static int stringK (FuncState *fs, TString *s) {
+  TValue o;
+  setsvalue(fs->ls->L, &o, s);
+  return addk(fs, &o, &o);  /* use string itself as key */
+}
+
+
+/*
+** Add an integer to list of constants and return its index.
+** Integers use userdata as keys to avoid collision with floats with
+** same value; conversion to 'void*' is used only for hashing, so there
+** are no "precision" problems.
+*/
+static int luaK_intK (FuncState *fs, lua_Integer n) {
+  TValue k, o;
+  setpvalue(&k, cast_voidp(cast_sizet(n)));
+  setivalue(&o, n);
+  return addk(fs, &k, &o);
+}
+
+/*
+** Add a float to list of constants and return its index.
+*/
+static int luaK_numberK (FuncState *fs, lua_Number r) {
+  TValue o;
+  setfltvalue(&o, r);
+  return addk(fs, &o, &o);  /* use number itself as key */
+}
+
+
+/*
+** Add a false to list of constants and return its index.
+*/
+static int boolF (FuncState *fs) {
+  TValue o;
+  setbfvalue(&o);
+  return addk(fs, &o, &o);  /* use boolean itself as key */
+}
+
+
+/*
+** Add a true to list of constants and return its index.
+*/
+static int boolT (FuncState *fs) {
+  TValue o;
+  setbtvalue(&o);
+  return addk(fs, &o, &o);  /* use boolean itself as key */
+}
+
+
+/*
+** Add nil to list of constants and return its index.
+*/
+static int nilK (FuncState *fs) {
+  TValue k, v;
+  setnilvalue(&v);
+  /* cannot use nil as key; instead use table itself to represent nil */
+  sethvalue(fs->ls->L, &k, fs->ls->h);
+  return addk(fs, &k, &v);
+}
+
+
+/*
+** Check whether 'i' can be stored in an 'sC' operand. Equivalent to
+** (0 <= int2sC(i) && int2sC(i) <= MAXARG_C) but without risk of
+** overflows in the hidden addition inside 'int2sC'.
+*/
+static int fitsC (lua_Integer i) {
+  return (l_castS2U(i) + OFFSET_sC <= cast_uint(MAXARG_C));
+}
+
+
+/*
+** Check whether 'i' can be stored in an 'sBx' operand.
+*/
+static int fitsBx (lua_Integer i) {
+  return (-OFFSET_sBx <= i && i <= MAXARG_Bx - OFFSET_sBx);
+}
+
+
+void luaK_int (FuncState *fs, int reg, lua_Integer i) {
+  if (fitsBx(i))
+    luaK_codeAsBx(fs, OP_LOADI, reg, cast_int(i));
+  else
+    luaK_codek(fs, reg, luaK_intK(fs, i));
+}
+
+
+static void luaK_float (FuncState *fs, int reg, lua_Number f) {
+  lua_Integer fi;
+  if (luaV_flttointeger(f, &fi, F2Ieq) && fitsBx(fi))
+    luaK_codeAsBx(fs, OP_LOADF, reg, cast_int(fi));
+  else
+    luaK_codek(fs, reg, luaK_numberK(fs, f));
+}
+
+
+/*
+** Convert a constant in 'v' into an expression description 'e'
+*/
+static void const2exp (TValue *v, expdesc *e) {
+  switch (ttypetag(v)) {
+    case LUA_VNUMINT:
+      e->k = VKINT; e->u.ival = ivalue(v);
+      break;
+    case LUA_VNUMFLT:
+      e->k = VKFLT; e->u.nval = fltvalue(v);
+      break;
+    case LUA_VFALSE:
+      e->k = VFALSE;
+      break;
+    case LUA_VTRUE:
+      e->k = VTRUE;
+      break;
+    case LUA_VNIL:
+      e->k = VNIL;
+      break;
+    case LUA_VSHRSTR:  case LUA_VLNGSTR:
+      e->k = VKSTR; e->u.strval = tsvalue(v);
+      break;
+    default: lua_assert(0);
+  }
+}
+
+
+/*
+** Fix an expression to return the number of results 'nresults'.
+** 'e' must be a multi-ret expression (function call or vararg).
+*/
+void luaK_setreturns (FuncState *fs, expdesc *e, int nresults) {
+  Instruction *pc = &getinstruction(fs, e);
+  if (e->k == VCALL)  /* expression is an open function call? */
+    SETARG_C(*pc, nresults + 1);
+  else {
+    lua_assert(e->k == VVARARG);
+    SETARG_C(*pc, nresults + 1);
+    SETARG_A(*pc, fs->freereg);
+    luaK_reserveregs(fs, 1);
+  }
+}
+
+
+/*
+** Convert a VKSTR to a VK
+*/
+static void str2K (FuncState *fs, expdesc *e) {
+  lua_assert(e->k == VKSTR);
+  e->u.info = stringK(fs, e->u.strval);
+  e->k = VK;
+}
+
+
+/*
+** Fix an expression to return one result.
+** If expression is not a multi-ret expression (function call or
+** vararg), it already returns one result, so nothing needs to be done.
+** Function calls become VNONRELOC expressions (as its result comes
+** fixed in the base register of the call), while vararg expressions
+** become VRELOC (as OP_VARARG puts its results where it wants).
+** (Calls are created returning one result, so that does not need
+** to be fixed.)
+*/
+void luaK_setoneret (FuncState *fs, expdesc *e) {
+  if (e->k == VCALL) {  /* expression is an open function call? */
+    /* already returns 1 value */
+    lua_assert(GETARG_C(getinstruction(fs, e)) == 2);
+    e->k = VNONRELOC;  /* result has fixed position */
+    e->u.info = GETARG_A(getinstruction(fs, e));
+  }
+  else if (e->k == VVARARG) {
+    SETARG_C(getinstruction(fs, e), 2);
+    e->k = VRELOC;  /* can relocate its simple result */
+  }
+}
+
+
+/*
+** Ensure that expression 'e' is not a variable (nor a constant).
+** (Expression still may have jump lists.)
+*/
+void luaK_dischargevars (FuncState *fs, expdesc *e) {
+  switch (e->k) {
+    case VCONST: {
+      const2exp(const2val(fs, e), e);
+      break;
+    }
+    case VLOCAL: {  /* already in a register */
+      e->u.info = e->u.var.sidx;
+      e->k = VNONRELOC;  /* becomes a non-relocatable value */
+      break;
+    }
+    case VUPVAL: {  /* move value to some (pending) register */
+      e->u.info = luaK_codeABC(fs, OP_GETUPVAL, 0, e->u.info, 0);
+      e->k = VRELOC;
+      break;
+    }
+    case VINDEXUP: {
+      e->u.info = luaK_codeABC(fs, OP_GETTABUP, 0, e->u.ind.t, e->u.ind.idx);
+      e->k = VRELOC;
+      break;
+    }
+    case VINDEXI: {
+      freereg(fs, e->u.ind.t);
+      e->u.info = luaK_codeABC(fs, OP_GETI, 0, e->u.ind.t, e->u.ind.idx);
+      e->k = VRELOC;
+      break;
+    }
+    case VINDEXSTR: {
+      freereg(fs, e->u.ind.t);
+      e->u.info = luaK_codeABC(fs, OP_GETFIELD, 0, e->u.ind.t, e->u.ind.idx);
+      e->k = VRELOC;
+      break;
+    }
+    case VINDEXED: {
+      freeregs(fs, e->u.ind.t, e->u.ind.idx);
+      e->u.info = luaK_codeABC(fs, OP_GETTABLE, 0, e->u.ind.t, e->u.ind.idx);
+      e->k = VRELOC;
+      break;
+    }
+    case VVARARG: case VCALL: {
+      luaK_setoneret(fs, e);
+      break;
+    }
+    default: break;  /* there is one value available (somewhere) */
+  }
+}
+
+
+/*
+** Ensures expression value is in register 'reg' (and therefore
+** 'e' will become a non-relocatable expression).
+** (Expression still may have jump lists.)
+*/
+static void discharge2reg (FuncState *fs, expdesc *e, int reg) {
+  luaK_dischargevars(fs, e);
+  switch (e->k) {
+    case VNIL: {
+      luaK_nil(fs, reg, 1);
+      break;
+    }
+    case VFALSE: {
+      luaK_codeABC(fs, OP_LOADFALSE, reg, 0, 0);
+      break;
+    }
+    case VTRUE: {
+      luaK_codeABC(fs, OP_LOADTRUE, reg, 0, 0);
+      break;
+    }
+    case VKSTR: {
+      str2K(fs, e);
+    }  /* FALLTHROUGH */
+    case VK: {
+      luaK_codek(fs, reg, e->u.info);
+      break;
+    }
+    case VKFLT: {
+      luaK_float(fs, reg, e->u.nval);
+      break;
+    }
+    case VKINT: {
+      luaK_int(fs, reg, e->u.ival);
+      break;
+    }
+    case VRELOC: {
+      Instruction *pc = &getinstruction(fs, e);
+      SETARG_A(*pc, reg);  /* instruction will put result in 'reg' */
+      break;
+    }
+    case VNONRELOC: {
+      if (reg != e->u.info)
+        luaK_codeABC(fs, OP_MOVE, reg, e->u.info, 0);
+      break;
+    }
+    default: {
+      lua_assert(e->k == VJMP);
+      return;  /* nothing to do... */
+    }
+  }
+  e->u.info = reg;
+  e->k = VNONRELOC;
+}
+
+
+/*
+** Ensures expression value is in any register.
+** (Expression still may have jump lists.)
+*/
+static void discharge2anyreg (FuncState *fs, expdesc *e) {
+  if (e->k != VNONRELOC) {  /* no fixed register yet? */
+    luaK_reserveregs(fs, 1);  /* get a register */
+    discharge2reg(fs, e, fs->freereg-1);  /* put value there */
+  }
+}
+
+
+static int code_loadbool (FuncState *fs, int A, OpCode op) {
+  luaK_getlabel(fs);  /* those instructions may be jump targets */
+  return luaK_codeABC(fs, op, A, 0, 0);
+}
+
+
+/*
+** check whether list has any jump that do not produce a value
+** or produce an inverted value
+*/
+static int need_value (FuncState *fs, int list) {
+  for (; list != NO_JUMP; list = getjump(fs, list)) {
+    Instruction i = *getjumpcontrol(fs, list);
+    if (GET_OPCODE(i) != OP_TESTSET) return 1;
+  }
+  return 0;  /* not found */
+}
+
+
+/*
+** Ensures final expression result (which includes results from its
+** jump lists) is in register 'reg'.
+** If expression has jumps, need to patch these jumps either to
+** its final position or to "load" instructions (for those tests
+** that do not produce values).
+*/
+static void exp2reg (FuncState *fs, expdesc *e, int reg) {
+  discharge2reg(fs, e, reg);
+  if (e->k == VJMP)  /* expression itself is a test? */
+    luaK_concat(fs, &e->t, e->u.info);  /* put this jump in 't' list */
+  if (hasjumps(e)) {
+    int final;  /* position after whole expression */
+    int p_f = NO_JUMP;  /* position of an eventual LOAD false */
+    int p_t = NO_JUMP;  /* position of an eventual LOAD true */
+    if (need_value(fs, e->t) || need_value(fs, e->f)) {
+      int fj = (e->k == VJMP) ? NO_JUMP : luaK_jump(fs);
+      p_f = code_loadbool(fs, reg, OP_LFALSESKIP);  /* skip next inst. */
+      p_t = code_loadbool(fs, reg, OP_LOADTRUE);
+      /* jump around these booleans if 'e' is not a test */
+      luaK_patchtohere(fs, fj);
+    }
+    final = luaK_getlabel(fs);
+    patchlistaux(fs, e->f, final, reg, p_f);
+    patchlistaux(fs, e->t, final, reg, p_t);
+  }
+  e->f = e->t = NO_JUMP;
+  e->u.info = reg;
+  e->k = VNONRELOC;
+}
+
+
+/*
+** Ensures final expression result is in next available register.
+*/
+void luaK_exp2nextreg (FuncState *fs, expdesc *e) {
+  luaK_dischargevars(fs, e);
+  freeexp(fs, e);
+  luaK_reserveregs(fs, 1);
+  exp2reg(fs, e, fs->freereg - 1);
+}
+
+
+/*
+** Ensures final expression result is in some (any) register
+** and return that register.
+*/
+int luaK_exp2anyreg (FuncState *fs, expdesc *e) {
+  luaK_dischargevars(fs, e);
+  if (e->k == VNONRELOC) {  /* expression already has a register? */
+    if (!hasjumps(e))  /* no jumps? */
+      return e->u.info;  /* result is already in a register */
+    if (e->u.info >= luaY_nvarstack(fs)) {  /* reg. is not a local? */
+      exp2reg(fs, e, e->u.info);  /* put final result in it */
+      return e->u.info;
+    }
+  }
+  luaK_exp2nextreg(fs, e);  /* otherwise, use next available register */
+  return e->u.info;
+}
+
+
+/*
+** Ensures final expression result is either in a register
+** or in an upvalue.
+*/
+void luaK_exp2anyregup (FuncState *fs, expdesc *e) {
+  if (e->k != VUPVAL || hasjumps(e))
+    luaK_exp2anyreg(fs, e);
+}
+
+
+/*
+** Ensures final expression result is either in a register
+** or it is a constant.
+*/
+void luaK_exp2val (FuncState *fs, expdesc *e) {
+  if (hasjumps(e))
+    luaK_exp2anyreg(fs, e);
+  else
+    luaK_dischargevars(fs, e);
+}
+
+
+/*
+** Try to make 'e' a K expression with an index in the range of R/K
+** indices. Return true iff succeeded.
+*/
+static int luaK_exp2K (FuncState *fs, expdesc *e) {
+  if (!hasjumps(e)) {
+    int info;
+    switch (e->k) {  /* move constants to 'k' */
+      case VTRUE: info = boolT(fs); break;
+      case VFALSE: info = boolF(fs); break;
+      case VNIL: info = nilK(fs); break;
+      case VKINT: info = luaK_intK(fs, e->u.ival); break;
+      case VKFLT: info = luaK_numberK(fs, e->u.nval); break;
+      case VKSTR: info = stringK(fs, e->u.strval); break;
+      case VK: info = e->u.info; break;
+      default: return 0;  /* not a constant */
+    }
+    if (info <= MAXINDEXRK) {  /* does constant fit in 'argC'? */
+      e->k = VK;  /* make expression a 'K' expression */
+      e->u.info = info;
+      return 1;
+    }
+  }
+  /* else, expression doesn't fit; leave it unchanged */
+  return 0;
+}
+
+
+/*
+** Ensures final expression result is in a valid R/K index
+** (that is, it is either in a register or in 'k' with an index
+** in the range of R/K indices).
+** Returns 1 iff expression is K.
+*/
+int luaK_exp2RK (FuncState *fs, expdesc *e) {
+  if (luaK_exp2K(fs, e))
+    return 1;
+  else {  /* not a constant in the right range: put it in a register */
+    luaK_exp2anyreg(fs, e);
+    return 0;
+  }
+}
+
+
+static void codeABRK (FuncState *fs, OpCode o, int a, int b,
+                      expdesc *ec) {
+  int k = luaK_exp2RK(fs, ec);
+  luaK_codeABCk(fs, o, a, b, ec->u.info, k);
+}
+
+
+/*
+** Generate code to store result of expression 'ex' into variable 'var'.
+*/
+void luaK_storevar (FuncState *fs, expdesc *var, expdesc *ex) {
+  switch (var->k) {
+    case VLOCAL: {
+      freeexp(fs, ex);
+      exp2reg(fs, ex, var->u.var.sidx);  /* compute 'ex' into proper place */
+      return;
+    }
+    case VUPVAL: {
+      int e = luaK_exp2anyreg(fs, ex);
+      luaK_codeABC(fs, OP_SETUPVAL, e, var->u.info, 0);
+      break;
+    }
+    case VINDEXUP: {
+      codeABRK(fs, OP_SETTABUP, var->u.ind.t, var->u.ind.idx, ex);
+      break;
+    }
+    case VINDEXI: {
+      codeABRK(fs, OP_SETI, var->u.ind.t, var->u.ind.idx, ex);
+      break;
+    }
+    case VINDEXSTR: {
+      codeABRK(fs, OP_SETFIELD, var->u.ind.t, var->u.ind.idx, ex);
+      break;
+    }
+    case VINDEXED: {
+      codeABRK(fs, OP_SETTABLE, var->u.ind.t, var->u.ind.idx, ex);
+      break;
+    }
+    default: lua_assert(0);  /* invalid var kind to store */
+  }
+  freeexp(fs, ex);
+}
+
+
+/*
+** Emit SELF instruction (convert expression 'e' into 'e:key(e,').
+*/
+void luaK_self (FuncState *fs, expdesc *e, expdesc *key) {
+  int ereg;
+  luaK_exp2anyreg(fs, e);
+  ereg = e->u.info;  /* register where 'e' was placed */
+  freeexp(fs, e);
+  e->u.info = fs->freereg;  /* base register for op_self */
+  e->k = VNONRELOC;  /* self expression has a fixed register */
+  luaK_reserveregs(fs, 2);  /* function and 'self' produced by op_self */
+  codeABRK(fs, OP_SELF, e->u.info, ereg, key);
+  freeexp(fs, key);
+}
+
+
+/*
+** Negate condition 'e' (where 'e' is a comparison).
+*/
+static void negatecondition (FuncState *fs, expdesc *e) {
+  Instruction *pc = getjumpcontrol(fs, e->u.info);
+  lua_assert(testTMode(GET_OPCODE(*pc)) && GET_OPCODE(*pc) != OP_TESTSET &&
+                                           GET_OPCODE(*pc) != OP_TEST);
+  SETARG_k(*pc, (GETARG_k(*pc) ^ 1));
+}
+
+
+/*
+** Emit instruction to jump if 'e' is 'cond' (that is, if 'cond'
+** is true, code will jump if 'e' is true.) Return jump position.
+** Optimize when 'e' is 'not' something, inverting the condition
+** and removing the 'not'.
+*/
+static int jumponcond (FuncState *fs, expdesc *e, int cond) {
+  if (e->k == VRELOC) {
+    Instruction ie = getinstruction(fs, e);
+    if (GET_OPCODE(ie) == OP_NOT) {
+      removelastinstruction(fs);  /* remove previous OP_NOT */
+      return condjump(fs, OP_TEST, GETARG_B(ie), 0, 0, !cond);
+    }
+    /* else go through */
+  }
+  discharge2anyreg(fs, e);
+  freeexp(fs, e);
+  return condjump(fs, OP_TESTSET, NO_REG, e->u.info, 0, cond);
+}
+
+
+/*
+** Emit code to go through if 'e' is true, jump otherwise.
+*/
+void luaK_goiftrue (FuncState *fs, expdesc *e) {
+  int pc;  /* pc of new jump */
+  luaK_dischargevars(fs, e);
+  switch (e->k) {
+    case VJMP: {  /* condition? */
+      negatecondition(fs, e);  /* jump when it is false */
+      pc = e->u.info;  /* save jump position */
+      break;
+    }
+    case VK: case VKFLT: case VKINT: case VKSTR: case VTRUE: {
+      pc = NO_JUMP;  /* always true; do nothing */
+      break;
+    }
+    default: {
+      pc = jumponcond(fs, e, 0);  /* jump when false */
+      break;
+    }
+  }
+  luaK_concat(fs, &e->f, pc);  /* insert new jump in false list */
+  luaK_patchtohere(fs, e->t);  /* true list jumps to here (to go through) */
+  e->t = NO_JUMP;
+}
+
+
+/*
+** Emit code to go through if 'e' is false, jump otherwise.
+*/
+void luaK_goiffalse (FuncState *fs, expdesc *e) {
+  int pc;  /* pc of new jump */
+  luaK_dischargevars(fs, e);
+  switch (e->k) {
+    case VJMP: {
+      pc = e->u.info;  /* already jump if true */
+      break;
+    }
+    case VNIL: case VFALSE: {
+      pc = NO_JUMP;  /* always false; do nothing */
+      break;
+    }
+    default: {
+      pc = jumponcond(fs, e, 1);  /* jump if true */
+      break;
+    }
+  }
+  luaK_concat(fs, &e->t, pc);  /* insert new jump in 't' list */
+  luaK_patchtohere(fs, e->f);  /* false list jumps to here (to go through) */
+  e->f = NO_JUMP;
+}
+
+
+/*
+** Code 'not e', doing constant folding.
+*/
+static void codenot (FuncState *fs, expdesc *e) {
+  switch (e->k) {
+    case VNIL: case VFALSE: {
+      e->k = VTRUE;  /* true == not nil == not false */
+      break;
+    }
+    case VK: case VKFLT: case VKINT: case VKSTR: case VTRUE: {
+      e->k = VFALSE;  /* false == not "x" == not 0.5 == not 1 == not true */
+      break;
+    }
+    case VJMP: {
+      negatecondition(fs, e);
+      break;
+    }
+    case VRELOC:
+    case VNONRELOC: {
+      discharge2anyreg(fs, e);
+      freeexp(fs, e);
+      e->u.info = luaK_codeABC(fs, OP_NOT, 0, e->u.info, 0);
+      e->k = VRELOC;
+      break;
+    }
+    default: lua_assert(0);  /* cannot happen */
+  }
+  /* interchange true and false lists */
+  { int temp = e->f; e->f = e->t; e->t = temp; }
+  removevalues(fs, e->f);  /* values are useless when negated */
+  removevalues(fs, e->t);
+}
+
+
+/*
+** Check whether expression 'e' is a small literal string
+*/
+static int isKstr (FuncState *fs, expdesc *e) {
+  return (e->k == VK && !hasjumps(e) && e->u.info <= MAXARG_B &&
+          ttisshrstring(&fs->f->k[e->u.info]));
+}
+
+/*
+** Check whether expression 'e' is a literal integer.
+*/
+int luaK_isKint (expdesc *e) {
+  return (e->k == VKINT && !hasjumps(e));
+}
+
+
+/*
+** Check whether expression 'e' is a literal integer in
+** proper range to fit in register C
+*/
+static int isCint (expdesc *e) {
+  return luaK_isKint(e) && (l_castS2U(e->u.ival) <= l_castS2U(MAXARG_C));
+}
+
+
+/*
+** Check whether expression 'e' is a literal integer in
+** proper range to fit in register sC
+*/
+static int isSCint (expdesc *e) {
+  return luaK_isKint(e) && fitsC(e->u.ival);
+}
+
+
+/*
+** Check whether expression 'e' is a literal integer or float in
+** proper range to fit in a register (sB or sC).
+*/
+static int isSCnumber (expdesc *e, int *pi, int *isfloat) {
+  lua_Integer i;
+  if (e->k == VKINT)
+    i = e->u.ival;
+  else if (e->k == VKFLT && luaV_flttointeger(e->u.nval, &i, F2Ieq))
+    *isfloat = 1;
+  else
+    return 0;  /* not a number */
+  if (!hasjumps(e) && fitsC(i)) {
+    *pi = int2sC(cast_int(i));
+    return 1;
+  }
+  else
+    return 0;
+}
+
+
+/*
+** Create expression 't[k]'. 't' must have its final result already in a
+** register or upvalue. Upvalues can only be indexed by literal strings.
+** Keys can be literal strings in the constant table or arbitrary
+** values in registers.
+*/
+void luaK_indexed (FuncState *fs, expdesc *t, expdesc *k) {
+  if (k->k == VKSTR)
+    str2K(fs, k);
+  lua_assert(!hasjumps(t) &&
+             (t->k == VLOCAL || t->k == VNONRELOC || t->k == VUPVAL));
+  if (t->k == VUPVAL && !isKstr(fs, k))  /* upvalue indexed by non 'Kstr'? */
+    luaK_exp2anyreg(fs, t);  /* put it in a register */
+  if (t->k == VUPVAL) {
+    t->u.ind.t = t->u.info;  /* upvalue index */
+    t->u.ind.idx = k->u.info;  /* literal string */
+    t->k = VINDEXUP;
+  }
+  else {
+    /* register index of the table */
+    t->u.ind.t = (t->k == VLOCAL) ? t->u.var.sidx: t->u.info;
+    if (isKstr(fs, k)) {
+      t->u.ind.idx = k->u.info;  /* literal string */
+      t->k = VINDEXSTR;
+    }
+    else if (isCint(k)) {
+      t->u.ind.idx = cast_int(k->u.ival);  /* int. constant in proper range */
+      t->k = VINDEXI;
+    }
+    else {
+      t->u.ind.idx = luaK_exp2anyreg(fs, k);  /* register */
+      t->k = VINDEXED;
+    }
+  }
+}
+
+
+/*
+** Return false if folding can raise an error.
+** Bitwise operations need operands convertible to integers; division
+** operations cannot have 0 as divisor.
+*/
+static int validop (int op, TValue *v1, TValue *v2) {
+  switch (op) {
+    case LUA_OPBAND: case LUA_OPBOR: case LUA_OPBXOR:
+    case LUA_OPSHL: case LUA_OPSHR: case LUA_OPBNOT: {  /* conversion errors */
+      lua_Integer i;
+      return (tointegerns(v1, &i) && tointegerns(v2, &i));
+    }
+    case LUA_OPDIV: case LUA_OPIDIV: case LUA_OPMOD:  /* division by 0 */
+      return (nvalue(v2) != 0);
+    default: return 1;  /* everything else is valid */
+  }
+}
+
+
+/*
+** Try to "constant-fold" an operation; return 1 iff successful.
+** (In this case, 'e1' has the final result.)
+*/
+static int constfolding (FuncState *fs, int op, expdesc *e1,
+                                        const expdesc *e2) {
+  TValue v1, v2, res;
+  if (!tonumeral(e1, &v1) || !tonumeral(e2, &v2) || !validop(op, &v1, &v2))
+    return 0;  /* non-numeric operands or not safe to fold */
+  luaO_rawarith(fs->ls->L, op, &v1, &v2, &res);  /* does operation */
+  if (ttisinteger(&res)) {
+    e1->k = VKINT;
+    e1->u.ival = ivalue(&res);
+  }
+  else {  /* folds neither NaN nor 0.0 (to avoid problems with -0.0) */
+    lua_Number n = fltvalue(&res);
+    if (luai_numisnan(n) || n == 0)
+      return 0;
+    e1->k = VKFLT;
+    e1->u.nval = n;
+  }
+  return 1;
+}
+
+
+/*
+** Emit code for unary expressions that "produce values"
+** (everything but 'not').
+** Expression to produce final result will be encoded in 'e'.
+*/
+static void codeunexpval (FuncState *fs, OpCode op, expdesc *e, int line) {
+  int r = luaK_exp2anyreg(fs, e);  /* opcodes operate only on registers */
+  freeexp(fs, e);
+  e->u.info = luaK_codeABC(fs, op, 0, r, 0);  /* generate opcode */
+  e->k = VRELOC;  /* all those operations are relocatable */
+  luaK_fixline(fs, line);
+}
+
+
+/*
+** Emit code for binary expressions that "produce values"
+** (everything but logical operators 'and'/'or' and comparison
+** operators).
+** Expression to produce final result will be encoded in 'e1'.
+*/
+static void finishbinexpval (FuncState *fs, expdesc *e1, expdesc *e2,
+                             OpCode op, int v2, int flip, int line,
+                             OpCode mmop, TMS event) {
+  int v1 = luaK_exp2anyreg(fs, e1);
+  int pc = luaK_codeABCk(fs, op, 0, v1, v2, 0);
+  freeexps(fs, e1, e2);
+  e1->u.info = pc;
+  e1->k = VRELOC;  /* all those operations are relocatable */
+  luaK_fixline(fs, line);
+  luaK_codeABCk(fs, mmop, v1, v2, event, flip);  /* to call metamethod */
+  luaK_fixline(fs, line);
+}
+
+
+/*
+** Emit code for binary expressions that "produce values" over
+** two registers.
+*/
+static void codebinexpval (FuncState *fs, OpCode op,
+                           expdesc *e1, expdesc *e2, int line) {
+  int v2 = luaK_exp2anyreg(fs, e2);  /* both operands are in registers */
+  lua_assert(OP_ADD <= op && op <= OP_SHR);
+  finishbinexpval(fs, e1, e2, op, v2, 0, line, OP_MMBIN,
+                  cast(TMS, (op - OP_ADD) + TM_ADD));
+}
+
+
+/*
+** Code binary operators with immediate operands.
+*/
+static void codebini (FuncState *fs, OpCode op,
+                       expdesc *e1, expdesc *e2, int flip, int line,
+                       TMS event) {
+  int v2 = int2sC(cast_int(e2->u.ival));  /* immediate operand */
+  lua_assert(e2->k == VKINT);
+  finishbinexpval(fs, e1, e2, op, v2, flip, line, OP_MMBINI, event);
+}
+
+
+/* Try to code a binary operator negating its second operand.
+** For the metamethod, 2nd operand must keep its original value.
+*/
+static int finishbinexpneg (FuncState *fs, expdesc *e1, expdesc *e2,
+                             OpCode op, int line, TMS event) {
+  if (!luaK_isKint(e2))
+    return 0;  /* not an integer constant */
+  else {
+    lua_Integer i2 = e2->u.ival;
+    if (!(fitsC(i2) && fitsC(-i2)))
+      return 0;  /* not in the proper range */
+    else {  /* operating a small integer constant */
+      int v2 = cast_int(i2);
+      finishbinexpval(fs, e1, e2, op, int2sC(-v2), 0, line, OP_MMBINI, event);
+      /* correct metamethod argument */
+      SETARG_B(fs->f->code[fs->pc - 1], int2sC(v2));
+      return 1;  /* successfully coded */
+    }
+  }
+}
+
+
+static void swapexps (expdesc *e1, expdesc *e2) {
+  expdesc temp = *e1; *e1 = *e2; *e2 = temp;  /* swap 'e1' and 'e2' */
+}
+
+
+/*
+** Code arithmetic operators ('+', '-', ...). If second operand is a
+** constant in the proper range, use variant opcodes with K operands.
+*/
+static void codearith (FuncState *fs, BinOpr opr,
+                       expdesc *e1, expdesc *e2, int flip, int line) {
+  TMS event = cast(TMS, opr + TM_ADD);
+  if (tonumeral(e2, NULL) && luaK_exp2K(fs, e2)) {  /* K operand? */
+    int v2 = e2->u.info;  /* K index */
+    OpCode op = cast(OpCode, opr + OP_ADDK);
+    finishbinexpval(fs, e1, e2, op, v2, flip, line, OP_MMBINK, event);
+  }
+  else {  /* 'e2' is neither an immediate nor a K operand */
+    OpCode op = cast(OpCode, opr + OP_ADD);
+    if (flip)
+      swapexps(e1, e2);  /* back to original order */
+    codebinexpval(fs, op, e1, e2, line);  /* use standard operators */
+  }
+}
+
+
+/*
+** Code commutative operators ('+', '*'). If first operand is a
+** numeric constant, change order of operands to try to use an
+** immediate or K operator.
+*/
+static void codecommutative (FuncState *fs, BinOpr op,
+                             expdesc *e1, expdesc *e2, int line) {
+  int flip = 0;
+  if (tonumeral(e1, NULL)) {  /* is first operand a numeric constant? */
+    swapexps(e1, e2);  /* change order */
+    flip = 1;
+  }
+  if (op == OPR_ADD && isSCint(e2))  /* immediate operand? */
+    codebini(fs, cast(OpCode, OP_ADDI), e1, e2, flip, line, TM_ADD);
+  else
+    codearith(fs, op, e1, e2, flip, line);
+}
+
+
+/*
+** Code bitwise operations; they are all associative, so the function
+** tries to put an integer constant as the 2nd operand (a K operand).
+*/
+static void codebitwise (FuncState *fs, BinOpr opr,
+                         expdesc *e1, expdesc *e2, int line) {
+  int flip = 0;
+  int v2;
+  OpCode op;
+  if (e1->k == VKINT && luaK_exp2RK(fs, e1)) {
+    swapexps(e1, e2);  /* 'e2' will be the constant operand */
+    flip = 1;
+  }
+  else if (!(e2->k == VKINT && luaK_exp2RK(fs, e2))) {  /* no constants? */
+    op = cast(OpCode, opr + OP_ADD);
+    codebinexpval(fs, op, e1, e2, line);  /* all-register opcodes */
+    return;
+  }
+  v2 = e2->u.info;  /* index in K array */
+  op = cast(OpCode, opr + OP_ADDK);
+  lua_assert(ttisinteger(&fs->f->k[v2]));
+  finishbinexpval(fs, e1, e2, op, v2, flip, line, OP_MMBINK,
+                  cast(TMS, opr + TM_ADD));
+}
+
+
+/*
+** Emit code for order comparisons. When using an immediate operand,
+** 'isfloat' tells whether the original value was a float.
+*/
+static void codeorder (FuncState *fs, OpCode op, expdesc *e1, expdesc *e2) {
+  int r1, r2;
+  int im;
+  int isfloat = 0;
+  if (isSCnumber(e2, &im, &isfloat)) {
+    /* use immediate operand */
+    r1 = luaK_exp2anyreg(fs, e1);
+    r2 = im;
+    op = cast(OpCode, (op - OP_LT) + OP_LTI);
+  }
+  else if (isSCnumber(e1, &im, &isfloat)) {
+    /* transform (A < B) to (B > A) and (A <= B) to (B >= A) */
+    r1 = luaK_exp2anyreg(fs, e2);
+    r2 = im;
+    op = (op == OP_LT) ? OP_GTI : OP_GEI;
+  }
+  else {  /* regular case, compare two registers */
+    r1 = luaK_exp2anyreg(fs, e1);
+    r2 = luaK_exp2anyreg(fs, e2);
+  }
+  freeexps(fs, e1, e2);
+  e1->u.info = condjump(fs, op, r1, r2, isfloat, 1);
+  e1->k = VJMP;
+}
+
+
+/*
+** Emit code for equality comparisons ('==', '~=').
+** 'e1' was already put as RK by 'luaK_infix'.
+*/
+static void codeeq (FuncState *fs, BinOpr opr, expdesc *e1, expdesc *e2) {
+  int r1, r2;
+  int im;
+  int isfloat = 0;  /* not needed here, but kept for symmetry */
+  OpCode op;
+  if (e1->k != VNONRELOC) {
+    lua_assert(e1->k == VK || e1->k == VKINT || e1->k == VKFLT);
+    swapexps(e1, e2);
+  }
+  r1 = luaK_exp2anyreg(fs, e1);  /* 1st expression must be in register */
+  if (isSCnumber(e2, &im, &isfloat)) {
+    op = OP_EQI;
+    r2 = im;  /* immediate operand */
+  }
+  else if (luaK_exp2RK(fs, e2)) {  /* 1st expression is constant? */
+    op = OP_EQK;
+    r2 = e2->u.info;  /* constant index */
+  }
+  else {
+    op = OP_EQ;  /* will compare two registers */
+    r2 = luaK_exp2anyreg(fs, e2);
+  }
+  freeexps(fs, e1, e2);
+  e1->u.info = condjump(fs, op, r1, r2, isfloat, (opr == OPR_EQ));
+  e1->k = VJMP;
+}
+
+
+/*
+** Apply prefix operation 'op' to expression 'e'.
+*/
+void luaK_prefix (FuncState *fs, UnOpr op, expdesc *e, int line) {
+  static const expdesc ef = {VKINT, {0}, NO_JUMP, NO_JUMP};
+  luaK_dischargevars(fs, e);
+  switch (op) {
+    case OPR_MINUS: case OPR_BNOT:  /* use 'ef' as fake 2nd operand */
+      if (constfolding(fs, op + LUA_OPUNM, e, &ef))
+        break;
+      /* else */ /* FALLTHROUGH */
+    case OPR_LEN:
+      codeunexpval(fs, cast(OpCode, op + OP_UNM), e, line);
+      break;
+    case OPR_NOT: codenot(fs, e); break;
+    default: lua_assert(0);
+  }
+}
+
+
+/*
+** Process 1st operand 'v' of binary operation 'op' before reading
+** 2nd operand.
+*/
+void luaK_infix (FuncState *fs, BinOpr op, expdesc *v) {
+  luaK_dischargevars(fs, v);
+  switch (op) {
+    case OPR_AND: {
+      luaK_goiftrue(fs, v);  /* go ahead only if 'v' is true */
+      break;
+    }
+    case OPR_OR: {
+      luaK_goiffalse(fs, v);  /* go ahead only if 'v' is false */
+      break;
+    }
+    case OPR_CONCAT: {
+      luaK_exp2nextreg(fs, v);  /* operand must be on the stack */
+      break;
+    }
+    case OPR_ADD: case OPR_SUB:
+    case OPR_MUL: case OPR_DIV: case OPR_IDIV:
+    case OPR_MOD: case OPR_POW:
+    case OPR_BAND: case OPR_BOR: case OPR_BXOR:
+    case OPR_SHL: case OPR_SHR: {
+      if (!tonumeral(v, NULL))
+        luaK_exp2anyreg(fs, v);
+      /* else keep numeral, which may be folded with 2nd operand */
+      break;
+    }
+    case OPR_EQ: case OPR_NE: {
+      if (!tonumeral(v, NULL))
+        luaK_exp2RK(fs, v);
+      /* else keep numeral, which may be an immediate operand */
+      break;
+    }
+    case OPR_LT: case OPR_LE:
+    case OPR_GT: case OPR_GE: {
+      int dummy, dummy2;
+      if (!isSCnumber(v, &dummy, &dummy2))
+        luaK_exp2anyreg(fs, v);
+      /* else keep numeral, which may be an immediate operand */
+      break;
+    }
+    default: lua_assert(0);
+  }
+}
+
+/*
+** Create code for '(e1 .. e2)'.
+** For '(e1 .. e2.1 .. e2.2)' (which is '(e1 .. (e2.1 .. e2.2))',
+** because concatenation is right associative), merge both CONCATs.
+*/
+static void codeconcat (FuncState *fs, expdesc *e1, expdesc *e2, int line) {
+  Instruction *ie2 = previousinstruction(fs);
+  if (GET_OPCODE(*ie2) == OP_CONCAT) {  /* is 'e2' a concatenation? */
+    int n = GETARG_B(*ie2);  /* # of elements concatenated in 'e2' */
+    lua_assert(e1->u.info + 1 == GETARG_A(*ie2));
+    freeexp(fs, e2);
+    SETARG_A(*ie2, e1->u.info);  /* correct first element ('e1') */
+    SETARG_B(*ie2, n + 1);  /* will concatenate one more element */
+  }
+  else {  /* 'e2' is not a concatenation */
+    luaK_codeABC(fs, OP_CONCAT, e1->u.info, 2, 0);  /* new concat opcode */
+    freeexp(fs, e2);
+    luaK_fixline(fs, line);
+  }
+}
+
+
+/*
+** Finalize code for binary operation, after reading 2nd operand.
+*/
+void luaK_posfix (FuncState *fs, BinOpr opr,
+                  expdesc *e1, expdesc *e2, int line) {
+  luaK_dischargevars(fs, e2);
+  if (foldbinop(opr) && constfolding(fs, opr + LUA_OPADD, e1, e2))
+    return;  /* done by folding */
+  switch (opr) {
+    case OPR_AND: {
+      lua_assert(e1->t == NO_JUMP);  /* list closed by 'luaK_infix' */
+      luaK_concat(fs, &e2->f, e1->f);
+      *e1 = *e2;
+      break;
+    }
+    case OPR_OR: {
+      lua_assert(e1->f == NO_JUMP);  /* list closed by 'luaK_infix' */
+      luaK_concat(fs, &e2->t, e1->t);
+      *e1 = *e2;
+      break;
+    }
+    case OPR_CONCAT: {  /* e1 .. e2 */
+      luaK_exp2nextreg(fs, e2);
+      codeconcat(fs, e1, e2, line);
+      break;
+    }
+    case OPR_ADD: case OPR_MUL: {
+      codecommutative(fs, opr, e1, e2, line);
+      break;
+    }
+    case OPR_SUB: {
+      if (finishbinexpneg(fs, e1, e2, OP_ADDI, line, TM_SUB))
+        break; /* coded as (r1 + -I) */
+      /* ELSE */
+    }  /* FALLTHROUGH */
+    case OPR_DIV: case OPR_IDIV: case OPR_MOD: case OPR_POW: {
+      codearith(fs, opr, e1, e2, 0, line);
+      break;
+    }
+    case OPR_BAND: case OPR_BOR: case OPR_BXOR: {
+      codebitwise(fs, opr, e1, e2, line);
+      break;
+    }
+    case OPR_SHL: {
+      if (isSCint(e1)) {
+        swapexps(e1, e2);
+        codebini(fs, OP_SHLI, e1, e2, 1, line, TM_SHL);  /* I << r2 */
+      }
+      else if (finishbinexpneg(fs, e1, e2, OP_SHRI, line, TM_SHL)) {
+        /* coded as (r1 >> -I) */;
+      }
+      else  /* regular case (two registers) */
+       codebinexpval(fs, OP_SHL, e1, e2, line);
+      break;
+    }
+    case OPR_SHR: {
+      if (isSCint(e2))
+        codebini(fs, OP_SHRI, e1, e2, 0, line, TM_SHR);  /* r1 >> I */
+      else  /* regular case (two registers) */
+        codebinexpval(fs, OP_SHR, e1, e2, line);
+      break;
+    }
+    case OPR_EQ: case OPR_NE: {
+      codeeq(fs, opr, e1, e2);
+      break;
+    }
+    case OPR_LT: case OPR_LE: {
+      OpCode op = cast(OpCode, (opr - OPR_EQ) + OP_EQ);
+      codeorder(fs, op, e1, e2);
+      break;
+    }
+    case OPR_GT: case OPR_GE: {
+      /* '(a > b)' <=> '(b < a)';  '(a >= b)' <=> '(b <= a)' */
+      OpCode op = cast(OpCode, (opr - OPR_NE) + OP_EQ);
+      swapexps(e1, e2);
+      codeorder(fs, op, e1, e2);
+      break;
+    }
+    default: lua_assert(0);
+  }
+}
+
+
+/*
+** Change line information associated with current position, by removing
+** previous info and adding it again with new line.
+*/
+void luaK_fixline (FuncState *fs, int line) {
+  removelastlineinfo(fs);
+  savelineinfo(fs, fs->f, line);
+}
+
+
+void luaK_settablesize (FuncState *fs, int pc, int ra, int asize, int hsize) {
+  Instruction *inst = &fs->f->code[pc];
+  int rb = (hsize != 0) ? luaO_ceillog2(hsize) + 1 : 0;  /* hash size */
+  int extra = asize / (MAXARG_C + 1);  /* higher bits of array size */
+  int rc = asize % (MAXARG_C + 1);  /* lower bits of array size */
+  int k = (extra > 0);  /* true iff needs extra argument */
+  *inst = CREATE_ABCk(OP_NEWTABLE, ra, rb, rc, k);
+  *(inst + 1) = CREATE_Ax(OP_EXTRAARG, extra);
+}
+
+
+/*
+** Emit a SETLIST instruction.
+** 'base' is register that keeps table;
+** 'nelems' is #table plus those to be stored now;
+** 'tostore' is number of values (in registers 'base + 1',...) to add to
+** table (or LUA_MULTRET to add up to stack top).
+*/
+void luaK_setlist (FuncState *fs, int base, int nelems, int tostore) {
+  lua_assert(tostore != 0 && tostore <= LFIELDS_PER_FLUSH);
+  if (tostore == LUA_MULTRET)
+    tostore = 0;
+  if (nelems <= MAXARG_C)
+    luaK_codeABC(fs, OP_SETLIST, base, tostore, nelems);
+  else {
+    int extra = nelems / (MAXARG_C + 1);
+    nelems %= (MAXARG_C + 1);
+    luaK_codeABCk(fs, OP_SETLIST, base, tostore, nelems, 1);
+    codeextraarg(fs, extra);
+  }
+  fs->freereg = base + 1;  /* free registers with list values */
+}
+
+
+/*
+** return the final target of a jump (skipping jumps to jumps)
+*/
+static int finaltarget (Instruction *code, int i) {
+  int count;
+  for (count = 0; count < 100; count++) {  /* avoid infinite loops */
+    Instruction pc = code[i];
+    if (GET_OPCODE(pc) != OP_JMP)
+      break;
+     else
+       i += GETARG_sJ(pc) + 1;
+  }
+  return i;
+}
+
+
+/*
+** Do a final pass over the code of a function, doing small peephole
+** optimizations and adjustments.
+*/
+void luaK_finish (FuncState *fs) {
+  int i;
+  Proto *p = fs->f;
+  for (i = 0; i < fs->pc; i++) {
+    Instruction *pc = &p->code[i];
+    lua_assert(i == 0 || isOT(*(pc - 1)) == isIT(*pc));
+    switch (GET_OPCODE(*pc)) {
+      case OP_RETURN0: case OP_RETURN1: {
+        if (!(fs->needclose || p->is_vararg))
+          break;  /* no extra work */
+        /* else use OP_RETURN to do the extra work */
+        SET_OPCODE(*pc, OP_RETURN);
+      }  /* FALLTHROUGH */
+      case OP_RETURN: case OP_TAILCALL: {
+        if (fs->needclose)
+          SETARG_k(*pc, 1);  /* signal that it needs to close */
+        if (p->is_vararg)
+          SETARG_C(*pc, p->numparams + 1);  /* signal that it is vararg */
+        break;
+      }
+      case OP_JMP: {
+        int target = finaltarget(p->code, i);
+        fixjump(fs, i, target);
+        break;
+      }
+      default: break;
+    }
+  }
+}
diff --git a/test/external/lua-5.4.0/src/lcode.h b/test/external/lua-5.4.0/src/lcode.h
new file mode 100644
index 0000000..3265824
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lcode.h
@@ -0,0 +1,104 @@
+/*
+** $Id: lcode.h $
+** Code generator for Lua
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lcode_h
+#define lcode_h
+
+#include "llex.h"
+#include "lobject.h"
+#include "lopcodes.h"
+#include "lparser.h"
+
+
+/*
+** Marks the end of a patch list. It is an invalid value both as an absolute
+** address, and as a list link (would link an element to itself).
+*/
+#define NO_JUMP (-1)
+
+
+/*
+** grep "ORDER OPR" if you change these enums  (ORDER OP)
+*/
+typedef enum BinOpr {
+  /* arithmetic operators */
+  OPR_ADD, OPR_SUB, OPR_MUL, OPR_MOD, OPR_POW,
+  OPR_DIV, OPR_IDIV,
+  /* bitwise operators */
+  OPR_BAND, OPR_BOR, OPR_BXOR,
+  OPR_SHL, OPR_SHR,
+  /* string operator */
+  OPR_CONCAT,
+  /* comparison operators */
+  OPR_EQ, OPR_LT, OPR_LE,
+  OPR_NE, OPR_GT, OPR_GE,
+  /* logical operators */
+  OPR_AND, OPR_OR,
+  OPR_NOBINOPR
+} BinOpr;
+
+
+/* true if operation is foldable (that is, it is arithmetic or bitwise) */
+#define foldbinop(op)	((op) <= OPR_SHR)
+
+
+#define luaK_codeABC(fs,o,a,b,c)	luaK_codeABCk(fs,o,a,b,c,0)
+
+
+typedef enum UnOpr { OPR_MINUS, OPR_BNOT, OPR_NOT, OPR_LEN, OPR_NOUNOPR } UnOpr;
+
+
+/* get (pointer to) instruction of given 'expdesc' */
+#define getinstruction(fs,e)	((fs)->f->code[(e)->u.info])
+
+
+#define luaK_setmultret(fs,e)	luaK_setreturns(fs, e, LUA_MULTRET)
+
+#define luaK_jumpto(fs,t)	luaK_patchlist(fs, luaK_jump(fs), t)
+
+LUAI_FUNC int luaK_code (FuncState *fs, Instruction i);
+LUAI_FUNC int luaK_codeABx (FuncState *fs, OpCode o, int A, unsigned int Bx);
+LUAI_FUNC int luaK_codeAsBx (FuncState *fs, OpCode o, int A, int Bx);
+LUAI_FUNC int luaK_codeABCk (FuncState *fs, OpCode o, int A,
+                                            int B, int C, int k);
+LUAI_FUNC int luaK_isKint (expdesc *e);
+LUAI_FUNC int luaK_exp2const (FuncState *fs, const expdesc *e, TValue *v);
+LUAI_FUNC void luaK_fixline (FuncState *fs, int line);
+LUAI_FUNC void luaK_nil (FuncState *fs, int from, int n);
+LUAI_FUNC void luaK_reserveregs (FuncState *fs, int n);
+LUAI_FUNC void luaK_checkstack (FuncState *fs, int n);
+LUAI_FUNC void luaK_int (FuncState *fs, int reg, lua_Integer n);
+LUAI_FUNC void luaK_dischargevars (FuncState *fs, expdesc *e);
+LUAI_FUNC int luaK_exp2anyreg (FuncState *fs, expdesc *e);
+LUAI_FUNC void luaK_exp2anyregup (FuncState *fs, expdesc *e);
+LUAI_FUNC void luaK_exp2nextreg (FuncState *fs, expdesc *e);
+LUAI_FUNC void luaK_exp2val (FuncState *fs, expdesc *e);
+LUAI_FUNC int luaK_exp2RK (FuncState *fs, expdesc *e);
+LUAI_FUNC void luaK_self (FuncState *fs, expdesc *e, expdesc *key);
+LUAI_FUNC void luaK_indexed (FuncState *fs, expdesc *t, expdesc *k);
+LUAI_FUNC void luaK_goiftrue (FuncState *fs, expdesc *e);
+LUAI_FUNC void luaK_goiffalse (FuncState *fs, expdesc *e);
+LUAI_FUNC void luaK_storevar (FuncState *fs, expdesc *var, expdesc *e);
+LUAI_FUNC void luaK_setreturns (FuncState *fs, expdesc *e, int nresults);
+LUAI_FUNC void luaK_setoneret (FuncState *fs, expdesc *e);
+LUAI_FUNC int luaK_jump (FuncState *fs);
+LUAI_FUNC void luaK_ret (FuncState *fs, int first, int nret);
+LUAI_FUNC void luaK_patchlist (FuncState *fs, int list, int target);
+LUAI_FUNC void luaK_patchtohere (FuncState *fs, int list);
+LUAI_FUNC void luaK_concat (FuncState *fs, int *l1, int l2);
+LUAI_FUNC int luaK_getlabel (FuncState *fs);
+LUAI_FUNC void luaK_prefix (FuncState *fs, UnOpr op, expdesc *v, int line);
+LUAI_FUNC void luaK_infix (FuncState *fs, BinOpr op, expdesc *v);
+LUAI_FUNC void luaK_posfix (FuncState *fs, BinOpr op, expdesc *v1,
+                            expdesc *v2, int line);
+LUAI_FUNC void luaK_settablesize (FuncState *fs, int pc,
+                                  int ra, int asize, int hsize);
+LUAI_FUNC void luaK_setlist (FuncState *fs, int base, int nelems, int tostore);
+LUAI_FUNC void luaK_finish (FuncState *fs);
+LUAI_FUNC l_noret luaK_semerror (LexState *ls, const char *msg);
+
+
+#endif
diff --git a/test/external/lua-5.4.0/src/lcorolib.c b/test/external/lua-5.4.0/src/lcorolib.c
new file mode 100644
index 0000000..7d6e585
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lcorolib.c
@@ -0,0 +1,206 @@
+/*
+** $Id: lcorolib.c $
+** Coroutine Library
+** See Copyright Notice in lua.h
+*/
+
+#define lcorolib_c
+#define LUA_LIB
+
+#include "lprefix.h"
+
+
+#include <stdlib.h>
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+static lua_State *getco (lua_State *L) {
+  lua_State *co = lua_tothread(L, 1);
+  luaL_argexpected(L, co, 1, "thread");
+  return co;
+}
+
+
+/*
+** Resumes a coroutine. Returns the number of results for non-error
+** cases or -1 for errors.
+*/
+static int auxresume (lua_State *L, lua_State *co, int narg) {
+  int status, nres;
+  if (!lua_checkstack(co, narg)) {
+    lua_pushliteral(L, "too many arguments to resume");
+    return -1;  /* error flag */
+  }
+  lua_xmove(L, co, narg);
+  status = lua_resume(co, L, narg, &nres);
+  if (status == LUA_OK || status == LUA_YIELD) {
+    if (!lua_checkstack(L, nres + 1)) {
+      lua_pop(co, nres);  /* remove results anyway */
+      lua_pushliteral(L, "too many results to resume");
+      return -1;  /* error flag */
+    }
+    lua_xmove(co, L, nres);  /* move yielded values */
+    return nres;
+  }
+  else {
+    lua_xmove(co, L, 1);  /* move error message */
+    return -1;  /* error flag */
+  }
+}
+
+
+static int luaB_coresume (lua_State *L) {
+  lua_State *co = getco(L);
+  int r;
+  r = auxresume(L, co, lua_gettop(L) - 1);
+  if (r < 0) {
+    lua_pushboolean(L, 0);
+    lua_insert(L, -2);
+    return 2;  /* return false + error message */
+  }
+  else {
+    lua_pushboolean(L, 1);
+    lua_insert(L, -(r + 1));
+    return r + 1;  /* return true + 'resume' returns */
+  }
+}
+
+
+static int luaB_auxwrap (lua_State *L) {
+  lua_State *co = lua_tothread(L, lua_upvalueindex(1));
+  int r = auxresume(L, co, lua_gettop(L));
+  if (r < 0) {
+    int stat = lua_status(co);
+    if (stat != LUA_OK && stat != LUA_YIELD)
+      lua_resetthread(co);  /* close variables in case of errors */
+    if (lua_type(L, -1) == LUA_TSTRING) {  /* error object is a string? */
+      luaL_where(L, 1);  /* add extra info, if available */
+      lua_insert(L, -2);
+      lua_concat(L, 2);
+    }
+    return lua_error(L);  /* propagate error */
+  }
+  return r;
+}
+
+
+static int luaB_cocreate (lua_State *L) {
+  lua_State *NL;
+  luaL_checktype(L, 1, LUA_TFUNCTION);
+  NL = lua_newthread(L);
+  lua_pushvalue(L, 1);  /* move function to top */
+  lua_xmove(L, NL, 1);  /* move function from L to NL */
+  return 1;
+}
+
+
+static int luaB_cowrap (lua_State *L) {
+  luaB_cocreate(L);
+  lua_pushcclosure(L, luaB_auxwrap, 1);
+  return 1;
+}
+
+
+static int luaB_yield (lua_State *L) {
+  return lua_yield(L, lua_gettop(L));
+}
+
+
+#define COS_RUN		0
+#define COS_DEAD	1
+#define COS_YIELD	2
+#define COS_NORM	3
+
+
+static const char *const statname[] =
+  {"running", "dead", "suspended", "normal"};
+
+
+static int auxstatus (lua_State *L, lua_State *co) {
+  if (L == co) return COS_RUN;
+  else {
+    switch (lua_status(co)) {
+      case LUA_YIELD:
+        return COS_YIELD;
+      case LUA_OK: {
+        lua_Debug ar;
+        if (lua_getstack(co, 0, &ar))  /* does it have frames? */
+          return COS_NORM;  /* it is running */
+        else if (lua_gettop(co) == 0)
+            return COS_DEAD;
+        else
+          return COS_YIELD;  /* initial state */
+      }
+      default:  /* some error occurred */
+        return COS_DEAD;
+    }
+  }
+}
+
+
+static int luaB_costatus (lua_State *L) {
+  lua_State *co = getco(L);
+  lua_pushstring(L, statname[auxstatus(L, co)]);
+  return 1;
+}
+
+
+static int luaB_yieldable (lua_State *L) {
+  lua_State *co = lua_isnone(L, 1) ? L : getco(L);
+  lua_pushboolean(L, lua_isyieldable(co));
+  return 1;
+}
+
+
+static int luaB_corunning (lua_State *L) {
+  int ismain = lua_pushthread(L);
+  lua_pushboolean(L, ismain);
+  return 2;
+}
+
+
+static int luaB_close (lua_State *L) {
+  lua_State *co = getco(L);
+  int status = auxstatus(L, co);
+  switch (status) {
+    case COS_DEAD: case COS_YIELD: {
+      status = lua_resetthread(co);
+      if (status == LUA_OK) {
+        lua_pushboolean(L, 1);
+        return 1;
+      }
+      else {
+        lua_pushboolean(L, 0);
+        lua_xmove(co, L, 1);  /* copy error message */
+        return 2;
+      }
+    }
+    default:  /* normal or running coroutine */
+      return luaL_error(L, "cannot close a %s coroutine", statname[status]);
+  }
+}
+
+
+static const luaL_Reg co_funcs[] = {
+  {"create", luaB_cocreate},
+  {"resume", luaB_coresume},
+  {"running", luaB_corunning},
+  {"status", luaB_costatus},
+  {"wrap", luaB_cowrap},
+  {"yield", luaB_yield},
+  {"isyieldable", luaB_yieldable},
+  {"close", luaB_close},
+  {NULL, NULL}
+};
+
+
+
+LUAMOD_API int luaopen_coroutine (lua_State *L) {
+  luaL_newlib(L, co_funcs);
+  return 1;
+}
+
diff --git a/test/external/lua-5.4.0/src/lctype.c b/test/external/lua-5.4.0/src/lctype.c
new file mode 100644
index 0000000..9542280
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lctype.c
@@ -0,0 +1,64 @@
+/*
+** $Id: lctype.c $
+** 'ctype' functions for Lua
+** See Copyright Notice in lua.h
+*/
+
+#define lctype_c
+#define LUA_CORE
+
+#include "lprefix.h"
+
+
+#include "lctype.h"
+
+#if !LUA_USE_CTYPE	/* { */
+
+#include <limits.h>
+
+
+#if defined (LUA_UCID)		/* accept UniCode IDentifiers? */
+/* consider all non-ascii codepoints to be alphabetic */
+#define NONA		0x01
+#else
+#define NONA		0x00	/* default */
+#endif
+
+
+LUAI_DDEF const lu_byte luai_ctype_[UCHAR_MAX + 2] = {
+  0x00,  /* EOZ */
+  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,	/* 0. */
+  0x00,  0x08,  0x08,  0x08,  0x08,  0x08,  0x00,  0x00,
+  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,	/* 1. */
+  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,
+  0x0c,  0x04,  0x04,  0x04,  0x04,  0x04,  0x04,  0x04,	/* 2. */
+  0x04,  0x04,  0x04,  0x04,  0x04,  0x04,  0x04,  0x04,
+  0x16,  0x16,  0x16,  0x16,  0x16,  0x16,  0x16,  0x16,	/* 3. */
+  0x16,  0x16,  0x04,  0x04,  0x04,  0x04,  0x04,  0x04,
+  0x04,  0x15,  0x15,  0x15,  0x15,  0x15,  0x15,  0x05,	/* 4. */
+  0x05,  0x05,  0x05,  0x05,  0x05,  0x05,  0x05,  0x05,
+  0x05,  0x05,  0x05,  0x05,  0x05,  0x05,  0x05,  0x05,	/* 5. */
+  0x05,  0x05,  0x05,  0x04,  0x04,  0x04,  0x04,  0x05,
+  0x04,  0x15,  0x15,  0x15,  0x15,  0x15,  0x15,  0x05,	/* 6. */
+  0x05,  0x05,  0x05,  0x05,  0x05,  0x05,  0x05,  0x05,
+  0x05,  0x05,  0x05,  0x05,  0x05,  0x05,  0x05,  0x05,	/* 7. */
+  0x05,  0x05,  0x05,  0x04,  0x04,  0x04,  0x04,  0x00,
+  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,	/* 8. */
+  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,
+  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,	/* 9. */
+  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,
+  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,	/* a. */
+  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,
+  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,	/* b. */
+  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,
+  0x00,  0x00,  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,	/* c. */
+  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,
+  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,	/* d. */
+  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,
+  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,	/* e. */
+  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,  NONA,
+  NONA,  NONA,  NONA,  NONA,  NONA,  0x00,  0x00,  0x00,	/* f. */
+  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00
+};
+
+#endif			/* } */
diff --git a/test/external/lua-5.4.0/src/lctype.h b/test/external/lua-5.4.0/src/lctype.h
new file mode 100644
index 0000000..cbff4d7
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lctype.h
@@ -0,0 +1,95 @@
+/*
+** $Id: lctype.h $
+** 'ctype' functions for Lua
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lctype_h
+#define lctype_h
+
+#include "lua.h"
+
+
+/*
+** WARNING: the functions defined here do not necessarily correspond
+** to the similar functions in the standard C ctype.h. They are
+** optimized for the specific needs of Lua
+*/
+
+#if !defined(LUA_USE_CTYPE)
+
+#if 'A' == 65 && '0' == 48
+/* ASCII case: can use its own tables; faster and fixed */
+#define LUA_USE_CTYPE	0
+#else
+/* must use standard C ctype */
+#define LUA_USE_CTYPE	1
+#endif
+
+#endif
+
+
+#if !LUA_USE_CTYPE	/* { */
+
+#include <limits.h>
+
+#include "llimits.h"
+
+
+#define ALPHABIT	0
+#define DIGITBIT	1
+#define PRINTBIT	2
+#define SPACEBIT	3
+#define XDIGITBIT	4
+
+
+#define MASK(B)		(1 << (B))
+
+
+/*
+** add 1 to char to allow index -1 (EOZ)
+*/
+#define testprop(c,p)	(luai_ctype_[(c)+1] & (p))
+
+/*
+** 'lalpha' (Lua alphabetic) and 'lalnum' (Lua alphanumeric) both include '_'
+*/
+#define lislalpha(c)	testprop(c, MASK(ALPHABIT))
+#define lislalnum(c)	testprop(c, (MASK(ALPHABIT) | MASK(DIGITBIT)))
+#define lisdigit(c)	testprop(c, MASK(DIGITBIT))
+#define lisspace(c)	testprop(c, MASK(SPACEBIT))
+#define lisprint(c)	testprop(c, MASK(PRINTBIT))
+#define lisxdigit(c)	testprop(c, MASK(XDIGITBIT))
+
+/*
+** this 'ltolower' only works for alphabetic characters
+*/
+#define ltolower(c)	((c) | ('A' ^ 'a'))
+
+
+/* two more entries for 0 and -1 (EOZ) */
+LUAI_DDEC(const lu_byte luai_ctype_[UCHAR_MAX + 2];)
+
+
+#else			/* }{ */
+
+/*
+** use standard C ctypes
+*/
+
+#include <ctype.h>
+
+
+#define lislalpha(c)	(isalpha(c) || (c) == '_')
+#define lislalnum(c)	(isalnum(c) || (c) == '_')
+#define lisdigit(c)	(isdigit(c))
+#define lisspace(c)	(isspace(c))
+#define lisprint(c)	(isprint(c))
+#define lisxdigit(c)	(isxdigit(c))
+
+#define ltolower(c)	(tolower(c))
+
+#endif			/* } */
+
+#endif
+
diff --git a/test/external/lua-5.4.0/src/ldblib.c b/test/external/lua-5.4.0/src/ldblib.c
new file mode 100644
index 0000000..59eb8f0
--- /dev/null
+++ b/test/external/lua-5.4.0/src/ldblib.c
@@ -0,0 +1,477 @@
+/*
+** $Id: ldblib.c $
+** Interface from Lua to its debug API
+** See Copyright Notice in lua.h
+*/
+
+#define ldblib_c
+#define LUA_LIB
+
+#include "lprefix.h"
+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+/*
+** The hook table at registry[HOOKKEY] maps threads to their current
+** hook function.
+*/
+static const char *const HOOKKEY = "_HOOKKEY";
+
+
+/*
+** If L1 != L, L1 can be in any state, and therefore there are no
+** guarantees about its stack space; any push in L1 must be
+** checked.
+*/
+static void checkstack (lua_State *L, lua_State *L1, int n) {
+  if (L != L1 && !lua_checkstack(L1, n))
+    luaL_error(L, "stack overflow");
+}
+
+
+static int db_getregistry (lua_State *L) {
+  lua_pushvalue(L, LUA_REGISTRYINDEX);
+  return 1;
+}
+
+
+static int db_getmetatable (lua_State *L) {
+  luaL_checkany(L, 1);
+  if (!lua_getmetatable(L, 1)) {
+    lua_pushnil(L);  /* no metatable */
+  }
+  return 1;
+}
+
+
+static int db_setmetatable (lua_State *L) {
+  int t = lua_type(L, 2);
+  luaL_argexpected(L, t == LUA_TNIL || t == LUA_TTABLE, 2, "nil or table");
+  lua_settop(L, 2);
+  lua_setmetatable(L, 1);
+  return 1;  /* return 1st argument */
+}
+
+
+static int db_getuservalue (lua_State *L) {
+  int n = (int)luaL_optinteger(L, 2, 1);
+  if (lua_type(L, 1) != LUA_TUSERDATA)
+    luaL_pushfail(L);
+  else if (lua_getiuservalue(L, 1, n) != LUA_TNONE) {
+    lua_pushboolean(L, 1);
+    return 2;
+  }
+  return 1;
+}
+
+
+static int db_setuservalue (lua_State *L) {
+  int n = (int)luaL_optinteger(L, 3, 1);
+  luaL_checktype(L, 1, LUA_TUSERDATA);
+  luaL_checkany(L, 2);
+  lua_settop(L, 2);
+  if (!lua_setiuservalue(L, 1, n))
+    luaL_pushfail(L);
+  return 1;
+}
+
+
+/*
+** Auxiliary function used by several library functions: check for
+** an optional thread as function's first argument and set 'arg' with
+** 1 if this argument is present (so that functions can skip it to
+** access their other arguments)
+*/
+static lua_State *getthread (lua_State *L, int *arg) {
+  if (lua_isthread(L, 1)) {
+    *arg = 1;
+    return lua_tothread(L, 1);
+  }
+  else {
+    *arg = 0;
+    return L;  /* function will operate over current thread */
+  }
+}
+
+
+/*
+** Variations of 'lua_settable', used by 'db_getinfo' to put results
+** from 'lua_getinfo' into result table. Key is always a string;
+** value can be a string, an int, or a boolean.
+*/
+static void settabss (lua_State *L, const char *k, const char *v) {
+  lua_pushstring(L, v);
+  lua_setfield(L, -2, k);
+}
+
+static void settabsi (lua_State *L, const char *k, int v) {
+  lua_pushinteger(L, v);
+  lua_setfield(L, -2, k);
+}
+
+static void settabsb (lua_State *L, const char *k, int v) {
+  lua_pushboolean(L, v);
+  lua_setfield(L, -2, k);
+}
+
+
+/*
+** In function 'db_getinfo', the call to 'lua_getinfo' may push
+** results on the stack; later it creates the result table to put
+** these objects. Function 'treatstackoption' puts the result from
+** 'lua_getinfo' on top of the result table so that it can call
+** 'lua_setfield'.
+*/
+static void treatstackoption (lua_State *L, lua_State *L1, const char *fname) {
+  if (L == L1)
+    lua_rotate(L, -2, 1);  /* exchange object and table */
+  else
+    lua_xmove(L1, L, 1);  /* move object to the "main" stack */
+  lua_setfield(L, -2, fname);  /* put object into table */
+}
+
+
+/*
+** Calls 'lua_getinfo' and collects all results in a new table.
+** L1 needs stack space for an optional input (function) plus
+** two optional outputs (function and line table) from function
+** 'lua_getinfo'.
+*/
+static int db_getinfo (lua_State *L) {
+  lua_Debug ar;
+  int arg;
+  lua_State *L1 = getthread(L, &arg);
+  const char *options = luaL_optstring(L, arg+2, "flnSrtu");
+  checkstack(L, L1, 3);
+  if (lua_isfunction(L, arg + 1)) {  /* info about a function? */
+    options = lua_pushfstring(L, ">%s", options);  /* add '>' to 'options' */
+    lua_pushvalue(L, arg + 1);  /* move function to 'L1' stack */
+    lua_xmove(L, L1, 1);
+  }
+  else {  /* stack level */
+    if (!lua_getstack(L1, (int)luaL_checkinteger(L, arg + 1), &ar)) {
+      luaL_pushfail(L);  /* level out of range */
+      return 1;
+    }
+  }
+  if (!lua_getinfo(L1, options, &ar))
+    return luaL_argerror(L, arg+2, "invalid option");
+  lua_newtable(L);  /* table to collect results */
+  if (strchr(options, 'S')) {
+    lua_pushlstring(L, ar.source, ar.srclen);
+    lua_setfield(L, -2, "source");
+    settabss(L, "short_src", ar.short_src);
+    settabsi(L, "linedefined", ar.linedefined);
+    settabsi(L, "lastlinedefined", ar.lastlinedefined);
+    settabss(L, "what", ar.what);
+  }
+  if (strchr(options, 'l'))
+    settabsi(L, "currentline", ar.currentline);
+  if (strchr(options, 'u')) {
+    settabsi(L, "nups", ar.nups);
+    settabsi(L, "nparams", ar.nparams);
+    settabsb(L, "isvararg", ar.isvararg);
+  }
+  if (strchr(options, 'n')) {
+    settabss(L, "name", ar.name);
+    settabss(L, "namewhat", ar.namewhat);
+  }
+  if (strchr(options, 'r')) {
+    settabsi(L, "ftransfer", ar.ftransfer);
+    settabsi(L, "ntransfer", ar.ntransfer);
+  }
+  if (strchr(options, 't'))
+    settabsb(L, "istailcall", ar.istailcall);
+  if (strchr(options, 'L'))
+    treatstackoption(L, L1, "activelines");
+  if (strchr(options, 'f'))
+    treatstackoption(L, L1, "func");
+  return 1;  /* return table */
+}
+
+
+static int db_getlocal (lua_State *L) {
+  int arg;
+  lua_State *L1 = getthread(L, &arg);
+  int nvar = (int)luaL_checkinteger(L, arg + 2);  /* local-variable index */
+  if (lua_isfunction(L, arg + 1)) {  /* function argument? */
+    lua_pushvalue(L, arg + 1);  /* push function */
+    lua_pushstring(L, lua_getlocal(L, NULL, nvar));  /* push local name */
+    return 1;  /* return only name (there is no value) */
+  }
+  else {  /* stack-level argument */
+    lua_Debug ar;
+    const char *name;
+    int level = (int)luaL_checkinteger(L, arg + 1);
+    if (!lua_getstack(L1, level, &ar))  /* out of range? */
+      return luaL_argerror(L, arg+1, "level out of range");
+    checkstack(L, L1, 1);
+    name = lua_getlocal(L1, &ar, nvar);
+    if (name) {
+      lua_xmove(L1, L, 1);  /* move local value */
+      lua_pushstring(L, name);  /* push name */
+      lua_rotate(L, -2, 1);  /* re-order */
+      return 2;
+    }
+    else {
+      luaL_pushfail(L);  /* no name (nor value) */
+      return 1;
+    }
+  }
+}
+
+
+static int db_setlocal (lua_State *L) {
+  int arg;
+  const char *name;
+  lua_State *L1 = getthread(L, &arg);
+  lua_Debug ar;
+  int level = (int)luaL_checkinteger(L, arg + 1);
+  int nvar = (int)luaL_checkinteger(L, arg + 2);
+  if (!lua_getstack(L1, level, &ar))  /* out of range? */
+    return luaL_argerror(L, arg+1, "level out of range");
+  luaL_checkany(L, arg+3);
+  lua_settop(L, arg+3);
+  checkstack(L, L1, 1);
+  lua_xmove(L, L1, 1);
+  name = lua_setlocal(L1, &ar, nvar);
+  if (name == NULL)
+    lua_pop(L1, 1);  /* pop value (if not popped by 'lua_setlocal') */
+  lua_pushstring(L, name);
+  return 1;
+}
+
+
+/*
+** get (if 'get' is true) or set an upvalue from a closure
+*/
+static int auxupvalue (lua_State *L, int get) {
+  const char *name;
+  int n = (int)luaL_checkinteger(L, 2);  /* upvalue index */
+  luaL_checktype(L, 1, LUA_TFUNCTION);  /* closure */
+  name = get ? lua_getupvalue(L, 1, n) : lua_setupvalue(L, 1, n);
+  if (name == NULL) return 0;
+  lua_pushstring(L, name);
+  lua_insert(L, -(get+1));  /* no-op if get is false */
+  return get + 1;
+}
+
+
+static int db_getupvalue (lua_State *L) {
+  return auxupvalue(L, 1);
+}
+
+
+static int db_setupvalue (lua_State *L) {
+  luaL_checkany(L, 3);
+  return auxupvalue(L, 0);
+}
+
+
+/*
+** Check whether a given upvalue from a given closure exists and
+** returns its index
+*/
+static int checkupval (lua_State *L, int argf, int argnup) {
+  int nup = (int)luaL_checkinteger(L, argnup);  /* upvalue index */
+  luaL_checktype(L, argf, LUA_TFUNCTION);  /* closure */
+  luaL_argcheck(L, (lua_getupvalue(L, argf, nup) != NULL), argnup,
+                   "invalid upvalue index");
+  return nup;
+}
+
+
+static int db_upvalueid (lua_State *L) {
+  int n = checkupval(L, 1, 2);
+  lua_pushlightuserdata(L, lua_upvalueid(L, 1, n));
+  return 1;
+}
+
+
+static int db_upvaluejoin (lua_State *L) {
+  int n1 = checkupval(L, 1, 2);
+  int n2 = checkupval(L, 3, 4);
+  luaL_argcheck(L, !lua_iscfunction(L, 1), 1, "Lua function expected");
+  luaL_argcheck(L, !lua_iscfunction(L, 3), 3, "Lua function expected");
+  lua_upvaluejoin(L, 1, n1, 3, n2);
+  return 0;
+}
+
+
+/*
+** Call hook function registered at hook table for the current
+** thread (if there is one)
+*/
+static void hookf (lua_State *L, lua_Debug *ar) {
+  static const char *const hooknames[] =
+    {"call", "return", "line", "count", "tail call"};
+  lua_getfield(L, LUA_REGISTRYINDEX, HOOKKEY);
+  lua_pushthread(L);
+  if (lua_rawget(L, -2) == LUA_TFUNCTION) {  /* is there a hook function? */
+    lua_pushstring(L, hooknames[(int)ar->event]);  /* push event name */
+    if (ar->currentline >= 0)
+      lua_pushinteger(L, ar->currentline);  /* push current line */
+    else lua_pushnil(L);
+    lua_assert(lua_getinfo(L, "lS", ar));
+    lua_call(L, 2, 0);  /* call hook function */
+  }
+}
+
+
+/*
+** Convert a string mask (for 'sethook') into a bit mask
+*/
+static int makemask (const char *smask, int count) {
+  int mask = 0;
+  if (strchr(smask, 'c')) mask |= LUA_MASKCALL;
+  if (strchr(smask, 'r')) mask |= LUA_MASKRET;
+  if (strchr(smask, 'l')) mask |= LUA_MASKLINE;
+  if (count > 0) mask |= LUA_MASKCOUNT;
+  return mask;
+}
+
+
+/*
+** Convert a bit mask (for 'gethook') into a string mask
+*/
+static char *unmakemask (int mask, char *smask) {
+  int i = 0;
+  if (mask & LUA_MASKCALL) smask[i++] = 'c';
+  if (mask & LUA_MASKRET) smask[i++] = 'r';
+  if (mask & LUA_MASKLINE) smask[i++] = 'l';
+  smask[i] = '\0';
+  return smask;
+}
+
+
+static int db_sethook (lua_State *L) {
+  int arg, mask, count;
+  lua_Hook func;
+  lua_State *L1 = getthread(L, &arg);
+  if (lua_isnoneornil(L, arg+1)) {  /* no hook? */
+    lua_settop(L, arg+1);
+    func = NULL; mask = 0; count = 0;  /* turn off hooks */
+  }
+  else {
+    const char *smask = luaL_checkstring(L, arg+2);
+    luaL_checktype(L, arg+1, LUA_TFUNCTION);
+    count = (int)luaL_optinteger(L, arg + 3, 0);
+    func = hookf; mask = makemask(smask, count);
+  }
+  if (!luaL_getsubtable(L, LUA_REGISTRYINDEX, HOOKKEY)) {
+    /* table just created; initialize it */
+    lua_pushstring(L, "k");
+    lua_setfield(L, -2, "__mode");  /** hooktable.__mode = "k" */
+    lua_pushvalue(L, -1);
+    lua_setmetatable(L, -2);  /* metatable(hooktable) = hooktable */
+  }
+  checkstack(L, L1, 1);
+  lua_pushthread(L1); lua_xmove(L1, L, 1);  /* key (thread) */
+  lua_pushvalue(L, arg + 1);  /* value (hook function) */
+  lua_rawset(L, -3);  /* hooktable[L1] = new Lua hook */
+  lua_sethook(L1, func, mask, count);
+  return 0;
+}
+
+
+static int db_gethook (lua_State *L) {
+  int arg;
+  lua_State *L1 = getthread(L, &arg);
+  char buff[5];
+  int mask = lua_gethookmask(L1);
+  lua_Hook hook = lua_gethook(L1);
+  if (hook == NULL) {  /* no hook? */
+    luaL_pushfail(L);
+    return 1;
+  }
+  else if (hook != hookf)  /* external hook? */
+    lua_pushliteral(L, "external hook");
+  else {  /* hook table must exist */
+    lua_getfield(L, LUA_REGISTRYINDEX, HOOKKEY);
+    checkstack(L, L1, 1);
+    lua_pushthread(L1); lua_xmove(L1, L, 1);
+    lua_rawget(L, -2);   /* 1st result = hooktable[L1] */
+    lua_remove(L, -2);  /* remove hook table */
+  }
+  lua_pushstring(L, unmakemask(mask, buff));  /* 2nd result = mask */
+  lua_pushinteger(L, lua_gethookcount(L1));  /* 3rd result = count */
+  return 3;
+}
+
+
+static int db_debug (lua_State *L) {
+  for (;;) {
+    char buffer[250];
+    lua_writestringerror("%s", "lua_debug> ");
+    if (fgets(buffer, sizeof(buffer), stdin) == 0 ||
+        strcmp(buffer, "cont\n") == 0)
+      return 0;
+    if (luaL_loadbuffer(L, buffer, strlen(buffer), "=(debug command)") ||
+        lua_pcall(L, 0, 0, 0))
+      lua_writestringerror("%s\n", luaL_tolstring(L, -1, NULL));
+    lua_settop(L, 0);  /* remove eventual returns */
+  }
+}
+
+
+static int db_traceback (lua_State *L) {
+  int arg;
+  lua_State *L1 = getthread(L, &arg);
+  const char *msg = lua_tostring(L, arg + 1);
+  if (msg == NULL && !lua_isnoneornil(L, arg + 1))  /* non-string 'msg'? */
+    lua_pushvalue(L, arg + 1);  /* return it untouched */
+  else {
+    int level = (int)luaL_optinteger(L, arg + 2, (L == L1) ? 1 : 0);
+    luaL_traceback(L, L1, msg, level);
+  }
+  return 1;
+}
+
+
+static int db_setcstacklimit (lua_State *L) {
+  int limit = (int)luaL_checkinteger(L, 1);
+  int res = lua_setcstacklimit(L, limit);
+  if (res == 0)
+    lua_pushboolean(L, 0);
+  else
+    lua_pushinteger(L, res);
+  return 1;
+}
+
+
+static const luaL_Reg dblib[] = {
+  {"debug", db_debug},
+  {"getuservalue", db_getuservalue},
+  {"gethook", db_gethook},
+  {"getinfo", db_getinfo},
+  {"getlocal", db_getlocal},
+  {"getregistry", db_getregistry},
+  {"getmetatable", db_getmetatable},
+  {"getupvalue", db_getupvalue},
+  {"upvaluejoin", db_upvaluejoin},
+  {"upvalueid", db_upvalueid},
+  {"setuservalue", db_setuservalue},
+  {"sethook", db_sethook},
+  {"setlocal", db_setlocal},
+  {"setmetatable", db_setmetatable},
+  {"setupvalue", db_setupvalue},
+  {"traceback", db_traceback},
+  {"setcstacklimit", db_setcstacklimit},
+  {NULL, NULL}
+};
+
+
+LUAMOD_API int luaopen_debug (lua_State *L) {
+  luaL_newlib(L, dblib);
+  return 1;
+}
+
diff --git a/test/external/lua-5.4.0/src/ldebug.c b/test/external/lua-5.4.0/src/ldebug.c
new file mode 100644
index 0000000..afdc2b7
--- /dev/null
+++ b/test/external/lua-5.4.0/src/ldebug.c
@@ -0,0 +1,841 @@
+/*
+** $Id: ldebug.c $
+** Debug Interface
+** See Copyright Notice in lua.h
+*/
+
+#define ldebug_c
+#define LUA_CORE
+
+#include "lprefix.h"
+
+
+#include <stdarg.h>
+#include <stddef.h>
+#include <string.h>
+
+#include "lua.h"
+
+#include "lapi.h"
+#include "lcode.h"
+#include "ldebug.h"
+#include "ldo.h"
+#include "lfunc.h"
+#include "lobject.h"
+#include "lopcodes.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "ltm.h"
+#include "lvm.h"
+
+
+
+#define noLuaClosure(f)		((f) == NULL || (f)->c.tt == LUA_VCCL)
+
+
+/* Active Lua function (given call info) */
+#define ci_func(ci)		(clLvalue(s2v((ci)->func)))
+
+
+static const char *funcnamefromcode (lua_State *L, CallInfo *ci,
+                                    const char **name);
+
+
+static int currentpc (CallInfo *ci) {
+  lua_assert(isLua(ci));
+  return pcRel(ci->u.l.savedpc, ci_func(ci)->p);
+}
+
+
+/*
+** Get a "base line" to find the line corresponding to an instruction.
+** For that, search the array of absolute line info for the largest saved
+** instruction smaller or equal to the wanted instruction. A special
+** case is when there is no absolute info or the instruction is before
+** the first absolute one.
+*/
+static int getbaseline (const Proto *f, int pc, int *basepc) {
+  if (f->sizeabslineinfo == 0 || pc < f->abslineinfo[0].pc) {
+    *basepc = -1;  /* start from the beginning */
+    return f->linedefined;
+  }
+  else {
+    unsigned int i;
+    if (pc >= f->abslineinfo[f->sizeabslineinfo - 1].pc)
+      i = f->sizeabslineinfo - 1;  /* instruction is after last saved one */
+    else {  /* binary search */
+      unsigned int j = f->sizeabslineinfo - 1;  /* pc < anchorlines[j] */
+      i = 0;  /* abslineinfo[i] <= pc */
+      while (i < j - 1) {
+        unsigned int m = (j + i) / 2;
+        if (pc >= f->abslineinfo[m].pc)
+          i = m;
+        else
+          j = m;
+      }
+    }
+    *basepc = f->abslineinfo[i].pc;
+    return f->abslineinfo[i].line;
+  }
+}
+
+
+/*
+** Get the line corresponding to instruction 'pc' in function 'f';
+** first gets a base line and from there does the increments until
+** the desired instruction.
+*/
+int luaG_getfuncline (const Proto *f, int pc) {
+  if (f->lineinfo == NULL)  /* no debug information? */
+    return -1;
+  else {
+    int basepc;
+    int baseline = getbaseline(f, pc, &basepc);
+    while (basepc++ < pc) {  /* walk until given instruction */
+      lua_assert(f->lineinfo[basepc] != ABSLINEINFO);
+      baseline += f->lineinfo[basepc];  /* correct line */
+    }
+    return baseline;
+  }
+}
+
+
+static int getcurrentline (CallInfo *ci) {
+  return luaG_getfuncline(ci_func(ci)->p, currentpc(ci));
+}
+
+
+/*
+** Set 'trap' for all active Lua frames.
+** This function can be called during a signal, under "reasonable"
+** assumptions. A new 'ci' is completely linked in the list before it
+** becomes part of the "active" list, and we assume that pointers are
+** atomic; see comment in next function.
+** (A compiler doing interprocedural optimizations could, theoretically,
+** reorder memory writes in such a way that the list could be
+** temporarily broken while inserting a new element. We simply assume it
+** has no good reasons to do that.)
+*/
+static void settraps (CallInfo *ci) {
+  for (; ci != NULL; ci = ci->previous)
+    if (isLua(ci))
+      ci->u.l.trap = 1;
+}
+
+
+/*
+** This function can be called during a signal, under "reasonable"
+** assumptions.
+** Fields 'oldpc', 'basehookcount', and 'hookcount' (set by
+** 'resethookcount') are for debug only, and it is no problem if they
+** get arbitrary values (causes at most one wrong hook call). 'hookmask'
+** is an atomic value. We assume that pointers are atomic too (e.g., gcc
+** ensures that for all platforms where it runs). Moreover, 'hook' is
+** always checked before being called (see 'luaD_hook').
+*/
+LUA_API void lua_sethook (lua_State *L, lua_Hook func, int mask, int count) {
+  if (func == NULL || mask == 0) {  /* turn off hooks? */
+    mask = 0;
+    func = NULL;
+  }
+  if (isLua(L->ci))
+    L->oldpc = L->ci->u.l.savedpc;
+  L->hook = func;
+  L->basehookcount = count;
+  resethookcount(L);
+  L->hookmask = cast_byte(mask);
+  if (mask)
+    settraps(L->ci);  /* to trace inside 'luaV_execute' */
+}
+
+
+LUA_API lua_Hook lua_gethook (lua_State *L) {
+  return L->hook;
+}
+
+
+LUA_API int lua_gethookmask (lua_State *L) {
+  return L->hookmask;
+}
+
+
+LUA_API int lua_gethookcount (lua_State *L) {
+  return L->basehookcount;
+}
+
+
+LUA_API int lua_getstack (lua_State *L, int level, lua_Debug *ar) {
+  int status;
+  CallInfo *ci;
+  if (level < 0) return 0;  /* invalid (negative) level */
+  lua_lock(L);
+  for (ci = L->ci; level > 0 && ci != &L->base_ci; ci = ci->previous)
+    level--;
+  if (level == 0 && ci != &L->base_ci) {  /* level found? */
+    status = 1;
+    ar->i_ci = ci;
+  }
+  else status = 0;  /* no such level */
+  lua_unlock(L);
+  return status;
+}
+
+
+static const char *upvalname (const Proto *p, int uv) {
+  TString *s = check_exp(uv < p->sizeupvalues, p->upvalues[uv].name);
+  if (s == NULL) return "?";
+  else return getstr(s);
+}
+
+
+static const char *findvararg (CallInfo *ci, int n, StkId *pos) {
+  if (clLvalue(s2v(ci->func))->p->is_vararg) {
+    int nextra = ci->u.l.nextraargs;
+    if (n <= nextra) {
+      *pos = ci->func - nextra + (n - 1);
+      return "(vararg)";  /* generic name for any vararg */
+    }
+  }
+  return NULL;  /* no such vararg */
+}
+
+
+const char *luaG_findlocal (lua_State *L, CallInfo *ci, int n, StkId *pos) {
+  StkId base = ci->func + 1;
+  const char *name = NULL;
+  if (isLua(ci)) {
+    if (n < 0)  /* access to vararg values? */
+      return findvararg(ci, -n, pos);
+    else
+      name = luaF_getlocalname(ci_func(ci)->p, n, currentpc(ci));
+  }
+  if (name == NULL) {  /* no 'standard' name? */
+    StkId limit = (ci == L->ci) ? L->top : ci->next->func;
+    if (limit - base >= n && n > 0) {  /* is 'n' inside 'ci' stack? */
+      /* generic name for any valid slot */
+      name = isLua(ci) ? "(temporary)" : "(C temporary)";
+    }
+    else
+      return NULL;  /* no name */
+  }
+  if (pos)
+    *pos = base + (n - 1);
+  return name;
+}
+
+
+LUA_API const char *lua_getlocal (lua_State *L, const lua_Debug *ar, int n) {
+  const char *name;
+  lua_lock(L);
+  if (ar == NULL) {  /* information about non-active function? */
+    if (!isLfunction(s2v(L->top - 1)))  /* not a Lua function? */
+      name = NULL;
+    else  /* consider live variables at function start (parameters) */
+      name = luaF_getlocalname(clLvalue(s2v(L->top - 1))->p, n, 0);
+  }
+  else {  /* active function; get information through 'ar' */
+    StkId pos = NULL;  /* to avoid warnings */
+    name = luaG_findlocal(L, ar->i_ci, n, &pos);
+    if (name) {
+      setobjs2s(L, L->top, pos);
+      api_incr_top(L);
+    }
+  }
+  lua_unlock(L);
+  return name;
+}
+
+
+LUA_API const char *lua_setlocal (lua_State *L, const lua_Debug *ar, int n) {
+  StkId pos = NULL;  /* to avoid warnings */
+  const char *name;
+  lua_lock(L);
+  name = luaG_findlocal(L, ar->i_ci, n, &pos);
+  if (name) {
+    setobjs2s(L, pos, L->top - 1);
+    L->top--;  /* pop value */
+  }
+  lua_unlock(L);
+  return name;
+}
+
+
+static void funcinfo (lua_Debug *ar, Closure *cl) {
+  if (noLuaClosure(cl)) {
+    ar->source = "=[C]";
+    ar->srclen = LL("=[C]");
+    ar->linedefined = -1;
+    ar->lastlinedefined = -1;
+    ar->what = "C";
+  }
+  else {
+    const Proto *p = cl->l.p;
+    if (p->source) {
+      ar->source = getstr(p->source);
+      ar->srclen = tsslen(p->source);
+    }
+    else {
+      ar->source = "=?";
+      ar->srclen = LL("=?");
+    }
+    ar->linedefined = p->linedefined;
+    ar->lastlinedefined = p->lastlinedefined;
+    ar->what = (ar->linedefined == 0) ? "main" : "Lua";
+  }
+  luaO_chunkid(ar->short_src, ar->source, ar->srclen);
+}
+
+
+static int nextline (const Proto *p, int currentline, int pc) {
+  if (p->lineinfo[pc] != ABSLINEINFO)
+    return currentline + p->lineinfo[pc];
+  else
+    return luaG_getfuncline(p, pc);
+}
+
+
+static void collectvalidlines (lua_State *L, Closure *f) {
+  if (noLuaClosure(f)) {
+    setnilvalue(s2v(L->top));
+    api_incr_top(L);
+  }
+  else {
+    int i;
+    TValue v;
+    const Proto *p = f->l.p;
+    int currentline = p->linedefined;
+    Table *t = luaH_new(L);  /* new table to store active lines */
+    sethvalue2s(L, L->top, t);  /* push it on stack */
+    api_incr_top(L);
+    setbtvalue(&v);  /* boolean 'true' to be the value of all indices */
+    for (i = 0; i < p->sizelineinfo; i++) {  /* for all lines with code */
+      currentline = nextline(p, currentline, i);
+      luaH_setint(L, t, currentline, &v);  /* table[line] = true */
+    }
+  }
+}
+
+
+static const char *getfuncname (lua_State *L, CallInfo *ci, const char **name) {
+  if (ci == NULL)  /* no 'ci'? */
+    return NULL;  /* no info */
+  else if (ci->callstatus & CIST_FIN) {  /* is this a finalizer? */
+    *name = "__gc";
+    return "metamethod";  /* report it as such */
+  }
+  /* calling function is a known Lua function? */
+  else if (!(ci->callstatus & CIST_TAIL) && isLua(ci->previous))
+    return funcnamefromcode(L, ci->previous, name);
+  else return NULL;  /* no way to find a name */
+}
+
+
+static int auxgetinfo (lua_State *L, const char *what, lua_Debug *ar,
+                       Closure *f, CallInfo *ci) {
+  int status = 1;
+  for (; *what; what++) {
+    switch (*what) {
+      case 'S': {
+        funcinfo(ar, f);
+        break;
+      }
+      case 'l': {
+        ar->currentline = (ci && isLua(ci)) ? getcurrentline(ci) : -1;
+        break;
+      }
+      case 'u': {
+        ar->nups = (f == NULL) ? 0 : f->c.nupvalues;
+        if (noLuaClosure(f)) {
+          ar->isvararg = 1;
+          ar->nparams = 0;
+        }
+        else {
+          ar->isvararg = f->l.p->is_vararg;
+          ar->nparams = f->l.p->numparams;
+        }
+        break;
+      }
+      case 't': {
+        ar->istailcall = (ci) ? ci->callstatus & CIST_TAIL : 0;
+        break;
+      }
+      case 'n': {
+        ar->namewhat = getfuncname(L, ci, &ar->name);
+        if (ar->namewhat == NULL) {
+          ar->namewhat = "";  /* not found */
+          ar->name = NULL;
+        }
+        break;
+      }
+      case 'r': {
+        if (ci == NULL || !(ci->callstatus & CIST_TRAN))
+          ar->ftransfer = ar->ntransfer = 0;
+        else {
+          ar->ftransfer = ci->u2.transferinfo.ftransfer;
+          ar->ntransfer = ci->u2.transferinfo.ntransfer;
+        }
+        break;
+      }
+      case 'L':
+      case 'f':  /* handled by lua_getinfo */
+        break;
+      default: status = 0;  /* invalid option */
+    }
+  }
+  return status;
+}
+
+
+LUA_API int lua_getinfo (lua_State *L, const char *what, lua_Debug *ar) {
+  int status;
+  Closure *cl;
+  CallInfo *ci;
+  TValue *func;
+  lua_lock(L);
+  if (*what == '>') {
+    ci = NULL;
+    func = s2v(L->top - 1);
+    api_check(L, ttisfunction(func), "function expected");
+    what++;  /* skip the '>' */
+    L->top--;  /* pop function */
+  }
+  else {
+    ci = ar->i_ci;
+    func = s2v(ci->func);
+    lua_assert(ttisfunction(func));
+  }
+  cl = ttisclosure(func) ? clvalue(func) : NULL;
+  status = auxgetinfo(L, what, ar, cl, ci);
+  if (strchr(what, 'f')) {
+    setobj2s(L, L->top, func);
+    api_incr_top(L);
+  }
+  if (strchr(what, 'L'))
+    collectvalidlines(L, cl);
+  lua_unlock(L);
+  return status;
+}
+
+
+/*
+** {======================================================
+** Symbolic Execution
+** =======================================================
+*/
+
+static const char *getobjname (const Proto *p, int lastpc, int reg,
+                               const char **name);
+
+
+/*
+** Find a "name" for the constant 'c'.
+*/
+static void kname (const Proto *p, int c, const char **name) {
+  TValue *kvalue = &p->k[c];
+  *name = (ttisstring(kvalue)) ? svalue(kvalue) : "?";
+}
+
+
+/*
+** Find a "name" for the register 'c'.
+*/
+static void rname (const Proto *p, int pc, int c, const char **name) {
+  const char *what = getobjname(p, pc, c, name); /* search for 'c' */
+  if (!(what && *what == 'c'))  /* did not find a constant name? */
+    *name = "?";
+}
+
+
+/*
+** Find a "name" for a 'C' value in an RK instruction.
+*/
+static void rkname (const Proto *p, int pc, Instruction i, const char **name) {
+  int c = GETARG_C(i);  /* key index */
+  if (GETARG_k(i))  /* is 'c' a constant? */
+    kname(p, c, name);
+  else  /* 'c' is a register */
+    rname(p, pc, c, name);
+}
+
+
+static int filterpc (int pc, int jmptarget) {
+  if (pc < jmptarget)  /* is code conditional (inside a jump)? */
+    return -1;  /* cannot know who sets that register */
+  else return pc;  /* current position sets that register */
+}
+
+
+/*
+** Try to find last instruction before 'lastpc' that modified register 'reg'.
+*/
+static int findsetreg (const Proto *p, int lastpc, int reg) {
+  int pc;
+  int setreg = -1;  /* keep last instruction that changed 'reg' */
+  int jmptarget = 0;  /* any code before this address is conditional */
+  if (testMMMode(GET_OPCODE(p->code[lastpc])))
+    lastpc--;  /* previous instruction was not actually executed */
+  for (pc = 0; pc < lastpc; pc++) {
+    Instruction i = p->code[pc];
+    OpCode op = GET_OPCODE(i);
+    int a = GETARG_A(i);
+    int change;  /* true if current instruction changed 'reg' */
+    switch (op) {
+      case OP_LOADNIL: {  /* set registers from 'a' to 'a+b' */
+        int b = GETARG_B(i);
+        change = (a <= reg && reg <= a + b);
+        break;
+      }
+      case OP_TFORCALL: {  /* affect all regs above its base */
+        change = (reg >= a + 2);
+        break;
+      }
+      case OP_CALL:
+      case OP_TAILCALL: {  /* affect all registers above base */
+        change = (reg >= a);
+        break;
+      }
+      case OP_JMP: {  /* doesn't change registers, but changes 'jmptarget' */
+        int b = GETARG_sJ(i);
+        int dest = pc + 1 + b;
+        /* jump does not skip 'lastpc' and is larger than current one? */
+        if (dest <= lastpc && dest > jmptarget)
+          jmptarget = dest;  /* update 'jmptarget' */
+        change = 0;
+        break;
+      }
+      default:  /* any instruction that sets A */
+        change = (testAMode(op) && reg == a);
+        break;
+    }
+    if (change)
+      setreg = filterpc(pc, jmptarget);
+  }
+  return setreg;
+}
+
+
+/*
+** Check whether table being indexed by instruction 'i' is the
+** environment '_ENV'
+*/
+static const char *gxf (const Proto *p, int pc, Instruction i, int isup) {
+  int t = GETARG_B(i);  /* table index */
+  const char *name;  /* name of indexed variable */
+  if (isup)  /* is an upvalue? */
+    name = upvalname(p, t);
+  else
+    getobjname(p, pc, t, &name);
+  return (name && strcmp(name, LUA_ENV) == 0) ? "global" : "field";
+}
+
+
+static const char *getobjname (const Proto *p, int lastpc, int reg,
+                               const char **name) {
+  int pc;
+  *name = luaF_getlocalname(p, reg + 1, lastpc);
+  if (*name)  /* is a local? */
+    return "local";
+  /* else try symbolic execution */
+  pc = findsetreg(p, lastpc, reg);
+  if (pc != -1) {  /* could find instruction? */
+    Instruction i = p->code[pc];
+    OpCode op = GET_OPCODE(i);
+    switch (op) {
+      case OP_MOVE: {
+        int b = GETARG_B(i);  /* move from 'b' to 'a' */
+        if (b < GETARG_A(i))
+          return getobjname(p, pc, b, name);  /* get name for 'b' */
+        break;
+      }
+      case OP_GETTABUP: {
+        int k = GETARG_C(i);  /* key index */
+        kname(p, k, name);
+        return gxf(p, pc, i, 1);
+      }
+      case OP_GETTABLE: {
+        int k = GETARG_C(i);  /* key index */
+        rname(p, pc, k, name);
+        return gxf(p, pc, i, 0);
+      }
+      case OP_GETI: {
+        *name = "integer index";
+        return "field";
+      }
+      case OP_GETFIELD: {
+        int k = GETARG_C(i);  /* key index */
+        kname(p, k, name);
+        return gxf(p, pc, i, 0);
+      }
+      case OP_GETUPVAL: {
+        *name = upvalname(p, GETARG_B(i));
+        return "upvalue";
+      }
+      case OP_LOADK:
+      case OP_LOADKX: {
+        int b = (op == OP_LOADK) ? GETARG_Bx(i)
+                                 : GETARG_Ax(p->code[pc + 1]);
+        if (ttisstring(&p->k[b])) {
+          *name = svalue(&p->k[b]);
+          return "constant";
+        }
+        break;
+      }
+      case OP_SELF: {
+        rkname(p, pc, i, name);
+        return "method";
+      }
+      default: break;  /* go through to return NULL */
+    }
+  }
+  return NULL;  /* could not find reasonable name */
+}
+
+
+/*
+** Try to find a name for a function based on the code that called it.
+** (Only works when function was called by a Lua function.)
+** Returns what the name is (e.g., "for iterator", "method",
+** "metamethod") and sets '*name' to point to the name.
+*/
+static const char *funcnamefromcode (lua_State *L, CallInfo *ci,
+                                     const char **name) {
+  TMS tm = (TMS)0;  /* (initial value avoids warnings) */
+  const Proto *p = ci_func(ci)->p;  /* calling function */
+  int pc = currentpc(ci);  /* calling instruction index */
+  Instruction i = p->code[pc];  /* calling instruction */
+  if (ci->callstatus & CIST_HOOKED) {  /* was it called inside a hook? */
+    *name = "?";
+    return "hook";
+  }
+  switch (GET_OPCODE(i)) {
+    case OP_CALL:
+    case OP_TAILCALL:
+      return getobjname(p, pc, GETARG_A(i), name);  /* get function name */
+    case OP_TFORCALL: {  /* for iterator */
+      *name = "for iterator";
+       return "for iterator";
+    }
+    /* other instructions can do calls through metamethods */
+    case OP_SELF: case OP_GETTABUP: case OP_GETTABLE:
+    case OP_GETI: case OP_GETFIELD:
+      tm = TM_INDEX;
+      break;
+    case OP_SETTABUP: case OP_SETTABLE: case OP_SETI: case OP_SETFIELD:
+      tm = TM_NEWINDEX;
+      break;
+    case OP_MMBIN: case OP_MMBINI: case OP_MMBINK: {
+      tm = cast(TMS, GETARG_C(i));
+      break;
+    }
+    case OP_UNM: tm = TM_UNM; break;
+    case OP_BNOT: tm = TM_BNOT; break;
+    case OP_LEN: tm = TM_LEN; break;
+    case OP_CONCAT: tm = TM_CONCAT; break;
+    case OP_EQ: tm = TM_EQ; break;
+    case OP_LT: case OP_LE: case OP_LTI: case OP_LEI:
+      *name = "order";  /* '<=' can call '__lt', etc. */
+      return "metamethod";
+    case OP_CLOSE: case OP_RETURN:
+      *name = "close";
+      return "metamethod";
+    default:
+      return NULL;  /* cannot find a reasonable name */
+  }
+  *name = getstr(G(L)->tmname[tm]) + 2;
+  return "metamethod";
+}
+
+/* }====================================================== */
+
+
+
+/*
+** The subtraction of two potentially unrelated pointers is
+** not ISO C, but it should not crash a program; the subsequent
+** checks are ISO C and ensure a correct result.
+*/
+static int isinstack (CallInfo *ci, const TValue *o) {
+  StkId base = ci->func + 1;
+  ptrdiff_t i = cast(StkId, o) - base;
+  return (0 <= i && i < (ci->top - base) && s2v(base + i) == o);
+}
+
+
+/*
+** Checks whether value 'o' came from an upvalue. (That can only happen
+** with instructions OP_GETTABUP/OP_SETTABUP, which operate directly on
+** upvalues.)
+*/
+static const char *getupvalname (CallInfo *ci, const TValue *o,
+                                 const char **name) {
+  LClosure *c = ci_func(ci);
+  int i;
+  for (i = 0; i < c->nupvalues; i++) {
+    if (c->upvals[i]->v == o) {
+      *name = upvalname(c->p, i);
+      return "upvalue";
+    }
+  }
+  return NULL;
+}
+
+
+static const char *varinfo (lua_State *L, const TValue *o) {
+  const char *name = NULL;  /* to avoid warnings */
+  CallInfo *ci = L->ci;
+  const char *kind = NULL;
+  if (isLua(ci)) {
+    kind = getupvalname(ci, o, &name);  /* check whether 'o' is an upvalue */
+    if (!kind && isinstack(ci, o))  /* no? try a register */
+      kind = getobjname(ci_func(ci)->p, currentpc(ci),
+                        cast_int(cast(StkId, o) - (ci->func + 1)), &name);
+  }
+  return (kind) ? luaO_pushfstring(L, " (%s '%s')", kind, name) : "";
+}
+
+
+l_noret luaG_typeerror (lua_State *L, const TValue *o, const char *op) {
+  const char *t = luaT_objtypename(L, o);
+  luaG_runerror(L, "attempt to %s a %s value%s", op, t, varinfo(L, o));
+}
+
+
+l_noret luaG_forerror (lua_State *L, const TValue *o, const char *what) {
+  luaG_runerror(L, "bad 'for' %s (number expected, got %s)",
+                   what, luaT_objtypename(L, o));
+}
+
+
+l_noret luaG_concaterror (lua_State *L, const TValue *p1, const TValue *p2) {
+  if (ttisstring(p1) || cvt2str(p1)) p1 = p2;
+  luaG_typeerror(L, p1, "concatenate");
+}
+
+
+l_noret luaG_opinterror (lua_State *L, const TValue *p1,
+                         const TValue *p2, const char *msg) {
+  if (!ttisnumber(p1))  /* first operand is wrong? */
+    p2 = p1;  /* now second is wrong */
+  luaG_typeerror(L, p2, msg);
+}
+
+
+/*
+** Error when both values are convertible to numbers, but not to integers
+*/
+l_noret luaG_tointerror (lua_State *L, const TValue *p1, const TValue *p2) {
+  lua_Integer temp;
+  if (!tointegerns(p1, &temp))
+    p2 = p1;
+  luaG_runerror(L, "number%s has no integer representation", varinfo(L, p2));
+}
+
+
+l_noret luaG_ordererror (lua_State *L, const TValue *p1, const TValue *p2) {
+  const char *t1 = luaT_objtypename(L, p1);
+  const char *t2 = luaT_objtypename(L, p2);
+  if (strcmp(t1, t2) == 0)
+    luaG_runerror(L, "attempt to compare two %s values", t1);
+  else
+    luaG_runerror(L, "attempt to compare %s with %s", t1, t2);
+}
+
+
+/* add src:line information to 'msg' */
+const char *luaG_addinfo (lua_State *L, const char *msg, TString *src,
+                                        int line) {
+  char buff[LUA_IDSIZE];
+  if (src)
+    luaO_chunkid(buff, getstr(src), tsslen(src));
+  else {  /* no source available; use "?" instead */
+    buff[0] = '?'; buff[1] = '\0';
+  }
+  return luaO_pushfstring(L, "%s:%d: %s", buff, line, msg);
+}
+
+
+l_noret luaG_errormsg (lua_State *L) {
+  if (L->errfunc != 0) {  /* is there an error handling function? */
+    StkId errfunc = restorestack(L, L->errfunc);
+    lua_assert(ttisfunction(s2v(errfunc)));
+    setobjs2s(L, L->top, L->top - 1);  /* move argument */
+    setobjs2s(L, L->top - 1, errfunc);  /* push function */
+    L->top++;  /* assume EXTRA_STACK */
+    luaD_callnoyield(L, L->top - 2, 1);  /* call it */
+  }
+  luaD_throw(L, LUA_ERRRUN);
+}
+
+
+l_noret luaG_runerror (lua_State *L, const char *fmt, ...) {
+  CallInfo *ci = L->ci;
+  const char *msg;
+  va_list argp;
+  luaC_checkGC(L);  /* error message uses memory */
+  va_start(argp, fmt);
+  msg = luaO_pushvfstring(L, fmt, argp);  /* format message */
+  va_end(argp);
+  if (isLua(ci))  /* if Lua function, add source:line information */
+    luaG_addinfo(L, msg, ci_func(ci)->p->source, getcurrentline(ci));
+  luaG_errormsg(L);
+}
+
+
+/*
+** Check whether new instruction 'newpc' is in a different line from
+** previous instruction 'oldpc'.
+*/
+static int changedline (const Proto *p, int oldpc, int newpc) {
+  while (oldpc++ < newpc) {
+    if (p->lineinfo[oldpc] != 0)
+      return (luaG_getfuncline(p, oldpc - 1) != luaG_getfuncline(p, newpc));
+  }
+  return 0;  /* no line changes in the way */
+}
+
+
+int luaG_traceexec (lua_State *L, const Instruction *pc) {
+  CallInfo *ci = L->ci;
+  lu_byte mask = L->hookmask;
+  int counthook;
+  if (!(mask & (LUA_MASKLINE | LUA_MASKCOUNT))) {  /* no hooks? */
+    ci->u.l.trap = 0;  /* don't need to stop again */
+    return 0;  /* turn off 'trap' */
+  }
+  pc++;  /* reference is always next instruction */
+  ci->u.l.savedpc = pc;  /* save 'pc' */
+  counthook = (--L->hookcount == 0 && (mask & LUA_MASKCOUNT));
+  if (counthook)
+    resethookcount(L);  /* reset count */
+  else if (!(mask & LUA_MASKLINE))
+    return 1;  /* no line hook and count != 0; nothing to be done now */
+  if (ci->callstatus & CIST_HOOKYIELD) {  /* called hook last time? */
+    ci->callstatus &= ~CIST_HOOKYIELD;  /* erase mark */
+    return 1;  /* do not call hook again (VM yielded, so it did not move) */
+  }
+  if (!isIT(*(ci->u.l.savedpc - 1)))
+    L->top = ci->top;  /* prepare top */
+  if (counthook)
+    luaD_hook(L, LUA_HOOKCOUNT, -1, 0, 0);  /* call count hook */
+  if (mask & LUA_MASKLINE) {
+    const Proto *p = ci_func(ci)->p;
+    int npci = pcRel(pc, p);
+    if (npci == 0 ||  /* call linehook when enter a new function, */
+        pc <= L->oldpc ||  /* when jump back (loop), or when */
+        changedline(p, pcRel(L->oldpc, p), npci)) {  /* enter new line */
+      int newline = luaG_getfuncline(p, npci);
+      luaD_hook(L, LUA_HOOKLINE, newline, 0, 0);  /* call line hook */
+    }
+    L->oldpc = pc;  /* 'pc' of last call to line hook */
+  }
+  if (L->status == LUA_YIELD) {  /* did hook yield? */
+    if (counthook)
+      L->hookcount = 1;  /* undo decrement to zero */
+    ci->u.l.savedpc--;  /* undo increment (resume will increment it again) */
+    ci->callstatus |= CIST_HOOKYIELD;  /* mark that it yielded */
+    luaD_throw(L, LUA_YIELD);
+  }
+  return 1;  /* keep 'trap' on */
+}
+
diff --git a/test/external/lua-5.4.0/src/ldebug.h b/test/external/lua-5.4.0/src/ldebug.h
new file mode 100644
index 0000000..1fe0efa
--- /dev/null
+++ b/test/external/lua-5.4.0/src/ldebug.h
@@ -0,0 +1,47 @@
+/*
+** $Id: ldebug.h $
+** Auxiliary functions from Debug Interface module
+** See Copyright Notice in lua.h
+*/
+
+#ifndef ldebug_h
+#define ldebug_h
+
+
+#include "lstate.h"
+
+
+#define pcRel(pc, p)	(cast_int((pc) - (p)->code) - 1)
+
+#define resethookcount(L)	(L->hookcount = L->basehookcount)
+
+/*
+** mark for entries in 'lineinfo' array that has absolute information in
+** 'abslineinfo' array
+*/
+#define ABSLINEINFO	(-0x80)
+
+LUAI_FUNC int luaG_getfuncline (const Proto *f, int pc);
+LUAI_FUNC const char *luaG_findlocal (lua_State *L, CallInfo *ci, int n,
+                                                    StkId *pos);
+LUAI_FUNC l_noret luaG_typeerror (lua_State *L, const TValue *o,
+                                                const char *opname);
+LUAI_FUNC l_noret luaG_forerror (lua_State *L, const TValue *o,
+                                               const char *what);
+LUAI_FUNC l_noret luaG_concaterror (lua_State *L, const TValue *p1,
+                                                  const TValue *p2);
+LUAI_FUNC l_noret luaG_opinterror (lua_State *L, const TValue *p1,
+                                                 const TValue *p2,
+                                                 const char *msg);
+LUAI_FUNC l_noret luaG_tointerror (lua_State *L, const TValue *p1,
+                                                 const TValue *p2);
+LUAI_FUNC l_noret luaG_ordererror (lua_State *L, const TValue *p1,
+                                                 const TValue *p2);
+LUAI_FUNC l_noret luaG_runerror (lua_State *L, const char *fmt, ...);
+LUAI_FUNC const char *luaG_addinfo (lua_State *L, const char *msg,
+                                                  TString *src, int line);
+LUAI_FUNC l_noret luaG_errormsg (lua_State *L);
+LUAI_FUNC int luaG_traceexec (lua_State *L, const Instruction *pc);
+
+
+#endif
diff --git a/test/external/lua-5.4.0/src/ldo.c b/test/external/lua-5.4.0/src/ldo.c
new file mode 100644
index 0000000..c563b1d
--- /dev/null
+++ b/test/external/lua-5.4.0/src/ldo.c
@@ -0,0 +1,822 @@
+/*
+** $Id: ldo.c $
+** Stack and Call structure of Lua
+** See Copyright Notice in lua.h
+*/
+
+#define ldo_c
+#define LUA_CORE
+
+#include "lprefix.h"
+
+
+#include <setjmp.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "lua.h"
+
+#include "lapi.h"
+#include "ldebug.h"
+#include "ldo.h"
+#include "lfunc.h"
+#include "lgc.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lopcodes.h"
+#include "lparser.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "ltm.h"
+#include "lundump.h"
+#include "lvm.h"
+#include "lzio.h"
+
+
+
+#define errorstatus(s)	((s) > LUA_YIELD)
+
+
+/*
+** {======================================================
+** Error-recovery functions
+** =======================================================
+*/
+
+/*
+** LUAI_THROW/LUAI_TRY define how Lua does exception handling. By
+** default, Lua handles errors with exceptions when compiling as
+** C++ code, with _longjmp/_setjmp when asked to use them, and with
+** longjmp/setjmp otherwise.
+*/
+#if !defined(LUAI_THROW)				/* { */
+
+#if defined(__cplusplus) && !defined(LUA_USE_LONGJMP)	/* { */
+
+/* C++ exceptions */
+#define LUAI_THROW(L,c)		throw(c)
+#define LUAI_TRY(L,c,a) \
+	try { a } catch(...) { if ((c)->status == 0) (c)->status = -1; }
+#define luai_jmpbuf		int  /* dummy variable */
+
+#elif defined(LUA_USE_POSIX)				/* }{ */
+
+/* in POSIX, try _longjmp/_setjmp (more efficient) */
+#define LUAI_THROW(L,c)		_longjmp((c)->b, 1)
+#define LUAI_TRY(L,c,a)		if (_setjmp((c)->b) == 0) { a }
+#define luai_jmpbuf		jmp_buf
+
+#else							/* }{ */
+
+/* ISO C handling with long jumps */
+#define LUAI_THROW(L,c)		longjmp((c)->b, 1)
+#define LUAI_TRY(L,c,a)		if (setjmp((c)->b) == 0) { a }
+#define luai_jmpbuf		jmp_buf
+
+#endif							/* } */
+
+#endif							/* } */
+
+
+
+/* chain list of long jump buffers */
+struct lua_longjmp {
+  struct lua_longjmp *previous;
+  luai_jmpbuf b;
+  volatile int status;  /* error code */
+};
+
+
+void luaD_seterrorobj (lua_State *L, int errcode, StkId oldtop) {
+  switch (errcode) {
+    case LUA_ERRMEM: {  /* memory error? */
+      setsvalue2s(L, oldtop, G(L)->memerrmsg); /* reuse preregistered msg. */
+      break;
+    }
+    case LUA_ERRERR: {
+      setsvalue2s(L, oldtop, luaS_newliteral(L, "error in error handling"));
+      break;
+    }
+    case CLOSEPROTECT: {
+      setnilvalue(s2v(oldtop));  /* no error message */
+      break;
+    }
+    default: {
+      setobjs2s(L, oldtop, L->top - 1);  /* error message on current top */
+      break;
+    }
+  }
+  L->top = oldtop + 1;
+}
+
+
+l_noret luaD_throw (lua_State *L, int errcode) {
+  if (L->errorJmp) {  /* thread has an error handler? */
+    L->errorJmp->status = errcode;  /* set status */
+    LUAI_THROW(L, L->errorJmp);  /* jump to it */
+  }
+  else {  /* thread has no error handler */
+    global_State *g = G(L);
+    errcode = luaF_close(L, L->stack, errcode);  /* close all upvalues */
+    L->status = cast_byte(errcode);  /* mark it as dead */
+    if (g->mainthread->errorJmp) {  /* main thread has a handler? */
+      setobjs2s(L, g->mainthread->top++, L->top - 1);  /* copy error obj. */
+      luaD_throw(g->mainthread, errcode);  /* re-throw in main thread */
+    }
+    else {  /* no handler at all; abort */
+      if (g->panic) {  /* panic function? */
+        luaD_seterrorobj(L, errcode, L->top);  /* assume EXTRA_STACK */
+        if (L->ci->top < L->top)
+          L->ci->top = L->top;  /* pushing msg. can break this invariant */
+        lua_unlock(L);
+        g->panic(L);  /* call panic function (last chance to jump out) */
+      }
+      abort();
+    }
+  }
+}
+
+
+int luaD_rawrunprotected (lua_State *L, Pfunc f, void *ud) {
+  global_State *g = G(L);
+  l_uint32 oldnCcalls = g->Cstacklimit - (L->nCcalls + L->nci);
+  struct lua_longjmp lj;
+  lj.status = LUA_OK;
+  lj.previous = L->errorJmp;  /* chain new error handler */
+  L->errorJmp = &lj;
+  LUAI_TRY(L, &lj,
+    (*f)(L, ud);
+  );
+  L->errorJmp = lj.previous;  /* restore old error handler */
+  L->nCcalls = g->Cstacklimit - oldnCcalls - L->nci;
+  return lj.status;
+}
+
+/* }====================================================== */
+
+
+/*
+** {==================================================================
+** Stack reallocation
+** ===================================================================
+*/
+static void correctstack (lua_State *L, StkId oldstack, StkId newstack) {
+  CallInfo *ci;
+  UpVal *up;
+  if (oldstack == newstack)
+    return;  /* stack address did not change */
+  L->top = (L->top - oldstack) + newstack;
+  for (up = L->openupval; up != NULL; up = up->u.open.next)
+    up->v = s2v((uplevel(up) - oldstack) + newstack);
+  for (ci = L->ci; ci != NULL; ci = ci->previous) {
+    ci->top = (ci->top - oldstack) + newstack;
+    ci->func = (ci->func - oldstack) + newstack;
+    if (isLua(ci))
+      ci->u.l.trap = 1;  /* signal to update 'trap' in 'luaV_execute' */
+  }
+}
+
+
+/* some space for error handling */
+#define ERRORSTACKSIZE	(LUAI_MAXSTACK + 200)
+
+
+int luaD_reallocstack (lua_State *L, int newsize, int raiseerror) {
+  int lim = L->stacksize;
+  StkId newstack = luaM_reallocvector(L, L->stack, lim, newsize, StackValue);
+  lua_assert(newsize <= LUAI_MAXSTACK || newsize == ERRORSTACKSIZE);
+  lua_assert(L->stack_last - L->stack == L->stacksize - EXTRA_STACK);
+  if (unlikely(newstack == NULL)) {  /* reallocation failed? */
+    if (raiseerror)
+      luaM_error(L);
+    else return 0;  /* do not raise an error */
+  }
+  for (; lim < newsize; lim++)
+    setnilvalue(s2v(newstack + lim)); /* erase new segment */
+  correctstack(L, L->stack, newstack);
+  L->stack = newstack;
+  L->stacksize = newsize;
+  L->stack_last = L->stack + newsize - EXTRA_STACK;
+  return 1;
+}
+
+
+/*
+** Try to grow the stack by at least 'n' elements. when 'raiseerror'
+** is true, raises any error; otherwise, return 0 in case of errors.
+*/
+int luaD_growstack (lua_State *L, int n, int raiseerror) {
+  int size = L->stacksize;
+  int newsize = 2 * size;  /* tentative new size */
+  if (unlikely(size > LUAI_MAXSTACK)) {  /* need more space after extra size? */
+    if (raiseerror)
+      luaD_throw(L, LUA_ERRERR);  /* error inside message handler */
+    else return 0;
+  }
+  else {
+    int needed = cast_int(L->top - L->stack) + n + EXTRA_STACK;
+    if (newsize > LUAI_MAXSTACK)  /* cannot cross the limit */
+      newsize = LUAI_MAXSTACK;
+    if (newsize < needed)  /* but must respect what was asked for */
+      newsize = needed;
+    if (unlikely(newsize > LUAI_MAXSTACK)) {  /* stack overflow? */
+      /* add extra size to be able to handle the error message */
+      luaD_reallocstack(L, ERRORSTACKSIZE, raiseerror);
+      if (raiseerror)
+        luaG_runerror(L, "stack overflow");
+      else return 0;
+    }
+  }  /* else no errors */
+  return luaD_reallocstack(L, newsize, raiseerror);
+}
+
+
+static int stackinuse (lua_State *L) {
+  CallInfo *ci;
+  StkId lim = L->top;
+  for (ci = L->ci; ci != NULL; ci = ci->previous) {
+    if (lim < ci->top) lim = ci->top;
+  }
+  lua_assert(lim <= L->stack_last);
+  return cast_int(lim - L->stack) + 1;  /* part of stack in use */
+}
+
+
+void luaD_shrinkstack (lua_State *L) {
+  int inuse = stackinuse(L);
+  int goodsize = inuse + (inuse / 8) + 2*EXTRA_STACK;
+  if (goodsize > LUAI_MAXSTACK)
+    goodsize = LUAI_MAXSTACK;  /* respect stack limit */
+  /* if thread is currently not handling a stack overflow and its
+     good size is smaller than current size, shrink its stack */
+  if (inuse <= (LUAI_MAXSTACK - EXTRA_STACK) &&
+      goodsize < L->stacksize)
+    luaD_reallocstack(L, goodsize, 0);  /* ok if that fails */
+  else  /* don't change stack */
+    condmovestack(L,{},{});  /* (change only for debugging) */
+  luaE_shrinkCI(L);  /* shrink CI list */
+}
+
+
+void luaD_inctop (lua_State *L) {
+  luaD_checkstack(L, 1);
+  L->top++;
+}
+
+/* }================================================================== */
+
+
+/*
+** Call a hook for the given event. Make sure there is a hook to be
+** called. (Both 'L->hook' and 'L->hookmask', which trigger this
+** function, can be changed asynchronously by signals.)
+*/
+void luaD_hook (lua_State *L, int event, int line,
+                              int ftransfer, int ntransfer) {
+  lua_Hook hook = L->hook;
+  if (hook && L->allowhook) {  /* make sure there is a hook */
+    int mask = CIST_HOOKED;
+    CallInfo *ci = L->ci;
+    ptrdiff_t top = savestack(L, L->top);
+    ptrdiff_t ci_top = savestack(L, ci->top);
+    lua_Debug ar;
+    ar.event = event;
+    ar.currentline = line;
+    ar.i_ci = ci;
+    if (ntransfer != 0) {
+      mask |= CIST_TRAN;  /* 'ci' has transfer information */
+      ci->u2.transferinfo.ftransfer = ftransfer;
+      ci->u2.transferinfo.ntransfer = ntransfer;
+    }
+    luaD_checkstack(L, LUA_MINSTACK);  /* ensure minimum stack size */
+    if (L->top + LUA_MINSTACK > ci->top)
+      ci->top = L->top + LUA_MINSTACK;
+    L->allowhook = 0;  /* cannot call hooks inside a hook */
+    ci->callstatus |= mask;
+    lua_unlock(L);
+    (*hook)(L, &ar);
+    lua_lock(L);
+    lua_assert(!L->allowhook);
+    L->allowhook = 1;
+    ci->top = restorestack(L, ci_top);
+    L->top = restorestack(L, top);
+    ci->callstatus &= ~mask;
+  }
+}
+
+
+/*
+** Executes a call hook for Lua functions. This function is called
+** whenever 'hookmask' is not zero, so it checks whether call hooks are
+** active.
+*/
+void luaD_hookcall (lua_State *L, CallInfo *ci) {
+  int hook = (ci->callstatus & CIST_TAIL) ? LUA_HOOKTAILCALL : LUA_HOOKCALL;
+  Proto *p;
+  if (!(L->hookmask & LUA_MASKCALL))  /* some other hook? */
+    return;  /* don't call hook */
+  p = clLvalue(s2v(ci->func))->p;
+  L->top = ci->top;  /* prepare top */
+  ci->u.l.savedpc++;  /* hooks assume 'pc' is already incremented */
+  luaD_hook(L, hook, -1, 1, p->numparams);
+  ci->u.l.savedpc--;  /* correct 'pc' */
+}
+
+
+static StkId rethook (lua_State *L, CallInfo *ci, StkId firstres, int nres) {
+  ptrdiff_t oldtop = savestack(L, L->top);  /* hook may change top */
+  int delta = 0;
+  if (isLuacode(ci)) {
+    Proto *p = clLvalue(s2v(ci->func))->p;
+    if (p->is_vararg)
+      delta = ci->u.l.nextraargs + p->numparams + 1;
+    if (L->top < ci->top)
+      L->top = ci->top;  /* correct top to run hook */
+  }
+  if (L->hookmask & LUA_MASKRET) {  /* is return hook on? */
+    int ftransfer;
+    ci->func += delta;  /* if vararg, back to virtual 'func' */
+    ftransfer = cast(unsigned short, firstres - ci->func);
+    luaD_hook(L, LUA_HOOKRET, -1, ftransfer, nres);  /* call it */
+    ci->func -= delta;
+  }
+  if (isLua(ci->previous))
+    L->oldpc = ci->previous->u.l.savedpc;  /* update 'oldpc' */
+  return restorestack(L, oldtop);
+}
+
+
+/*
+** Check whether 'func' has a '__call' metafield. If so, put it in the
+** stack, below original 'func', so that 'luaD_call' can call it. Raise
+** an error if there is no '__call' metafield.
+*/
+void luaD_tryfuncTM (lua_State *L, StkId func) {
+  const TValue *tm = luaT_gettmbyobj(L, s2v(func), TM_CALL);
+  StkId p;
+  if (unlikely(ttisnil(tm)))
+    luaG_typeerror(L, s2v(func), "call");  /* nothing to call */
+  for (p = L->top; p > func; p--)  /* open space for metamethod */
+    setobjs2s(L, p, p-1);
+  L->top++;  /* stack space pre-allocated by the caller */
+  setobj2s(L, func, tm);  /* metamethod is the new function to be called */
+}
+
+
+/*
+** Given 'nres' results at 'firstResult', move 'wanted' of them to 'res'.
+** Handle most typical cases (zero results for commands, one result for
+** expressions, multiple results for tail calls/single parameters)
+** separated.
+*/
+static void moveresults (lua_State *L, StkId res, int nres, int wanted) {
+  StkId firstresult;
+  int i;
+  switch (wanted) {  /* handle typical cases separately */
+    case 0:  /* no values needed */
+      L->top = res;
+      return;
+    case 1:  /* one value needed */
+      if (nres == 0)   /* no results? */
+        setnilvalue(s2v(res));  /* adjust with nil */
+      else
+        setobjs2s(L, res, L->top - nres);  /* move it to proper place */
+      L->top = res + 1;
+      return;
+    case LUA_MULTRET:
+      wanted = nres;  /* we want all results */
+      break;
+    default:  /* multiple results (or to-be-closed variables) */
+      if (hastocloseCfunc(wanted)) {  /* to-be-closed variables? */
+        ptrdiff_t savedres = savestack(L, res);
+        luaF_close(L, res, LUA_OK);  /* may change the stack */
+        res = restorestack(L, savedres);
+        wanted = codeNresults(wanted);  /* correct value */
+        if (wanted == LUA_MULTRET)
+          wanted = nres;
+      }
+      break;
+  }
+  firstresult = L->top - nres;  /* index of first result */
+  /* move all results to correct place */
+  for (i = 0; i < nres && i < wanted; i++)
+    setobjs2s(L, res + i, firstresult + i);
+  for (; i < wanted; i++)  /* complete wanted number of results */
+    setnilvalue(s2v(res + i));
+  L->top = res + wanted;  /* top points after the last result */
+}
+
+
+/*
+** Finishes a function call: calls hook if necessary, removes CallInfo,
+** moves current number of results to proper place.
+*/
+void luaD_poscall (lua_State *L, CallInfo *ci, int nres) {
+  if (L->hookmask)
+    L->top = rethook(L, ci, L->top - nres, nres);
+  L->ci = ci->previous;  /* back to caller */
+  /* move results to proper place */
+  moveresults(L, ci->func, nres, ci->nresults);
+}
+
+
+
+#define next_ci(L)  (L->ci->next ? L->ci->next : luaE_extendCI(L))
+
+
+/*
+** Prepare a function for a tail call, building its call info on top
+** of the current call info. 'narg1' is the number of arguments plus 1
+** (so that it includes the function itself).
+*/
+void luaD_pretailcall (lua_State *L, CallInfo *ci, StkId func, int narg1) {
+  Proto *p = clLvalue(s2v(func))->p;
+  int fsize = p->maxstacksize;  /* frame size */
+  int nfixparams = p->numparams;
+  int i;
+  for (i = 0; i < narg1; i++)  /* move down function and arguments */
+    setobjs2s(L, ci->func + i, func + i);
+  checkstackGC(L, fsize);
+  func = ci->func;  /* moved-down function */
+  for (; narg1 <= nfixparams; narg1++)
+    setnilvalue(s2v(func + narg1));  /* complete missing arguments */
+  ci->top = func + 1 + fsize;  /* top for new function */
+  lua_assert(ci->top <= L->stack_last);
+  ci->u.l.savedpc = p->code;  /* starting point */
+  ci->callstatus |= CIST_TAIL;
+  L->top = func + narg1;  /* set top */
+}
+
+
+/*
+** Call a function (C or Lua). The function to be called is at *func.
+** The arguments are on the stack, right after the function.
+** When returns, all the results are on the stack, starting at the original
+** function position.
+*/
+void luaD_call (lua_State *L, StkId func, int nresults) {
+  lua_CFunction f;
+ retry:
+  switch (ttypetag(s2v(func))) {
+    case LUA_VCCL:  /* C closure */
+      f = clCvalue(s2v(func))->f;
+      goto Cfunc;
+    case LUA_VLCF:  /* light C function */
+      f = fvalue(s2v(func));
+     Cfunc: {
+      int n;  /* number of returns */
+      CallInfo *ci = next_ci(L);
+      checkstackp(L, LUA_MINSTACK, func);  /* ensure minimum stack size */
+      ci->nresults = nresults;
+      ci->callstatus = CIST_C;
+      ci->top = L->top + LUA_MINSTACK;
+      ci->func = func;
+      L->ci = ci;
+      lua_assert(ci->top <= L->stack_last);
+      if (L->hookmask & LUA_MASKCALL) {
+        int narg = cast_int(L->top - func) - 1;
+        luaD_hook(L, LUA_HOOKCALL, -1, 1, narg);
+      }
+      lua_unlock(L);
+      n = (*f)(L);  /* do the actual call */
+      lua_lock(L);
+      api_checknelems(L, n);
+      luaD_poscall(L, ci, n);
+      break;
+    }
+    case LUA_VLCL: {  /* Lua function */
+      CallInfo *ci = next_ci(L);
+      Proto *p = clLvalue(s2v(func))->p;
+      int narg = cast_int(L->top - func) - 1;  /* number of real arguments */
+      int nfixparams = p->numparams;
+      int fsize = p->maxstacksize;  /* frame size */
+      checkstackp(L, fsize, func);
+      ci->nresults = nresults;
+      ci->u.l.savedpc = p->code;  /* starting point */
+      ci->callstatus = 0;
+      ci->top = func + 1 + fsize;
+      ci->func = func;
+      L->ci = ci;
+      for (; narg < nfixparams; narg++)
+        setnilvalue(s2v(L->top++));  /* complete missing arguments */
+      lua_assert(ci->top <= L->stack_last);
+      luaV_execute(L, ci);  /* run the function */
+      break;
+    }
+    default: {  /* not a function */
+      checkstackp(L, 1, func);  /* space for metamethod */
+      luaD_tryfuncTM(L, func);  /* try to get '__call' metamethod */
+      goto retry;  /* try again with metamethod */
+    }
+  }
+}
+
+
+/*
+** Similar to 'luaD_call', but does not allow yields during the call.
+** If there is a stack overflow, freeing all CI structures will
+** force the subsequent call to invoke 'luaE_extendCI', which then
+** will raise any errors.
+*/
+void luaD_callnoyield (lua_State *L, StkId func, int nResults) {
+  incXCcalls(L);
+  if (getCcalls(L) <= CSTACKERR)  /* possible stack overflow? */
+    luaE_freeCI(L);
+  luaD_call(L, func, nResults);
+  decXCcalls(L);
+}
+
+
+/*
+** Completes the execution of an interrupted C function, calling its
+** continuation function.
+*/
+static void finishCcall (lua_State *L, int status) {
+  CallInfo *ci = L->ci;
+  int n;
+  /* must have a continuation and must be able to call it */
+  lua_assert(ci->u.c.k != NULL && yieldable(L));
+  /* error status can only happen in a protected call */
+  lua_assert((ci->callstatus & CIST_YPCALL) || status == LUA_YIELD);
+  if (ci->callstatus & CIST_YPCALL) {  /* was inside a pcall? */
+    ci->callstatus &= ~CIST_YPCALL;  /* continuation is also inside it */
+    L->errfunc = ci->u.c.old_errfunc;  /* with the same error function */
+  }
+  /* finish 'lua_callk'/'lua_pcall'; CIST_YPCALL and 'errfunc' already
+     handled */
+  adjustresults(L, ci->nresults);
+  lua_unlock(L);
+  n = (*ci->u.c.k)(L, status, ci->u.c.ctx);  /* call continuation function */
+  lua_lock(L);
+  api_checknelems(L, n);
+  luaD_poscall(L, ci, n);  /* finish 'luaD_call' */
+}
+
+
+/*
+** Executes "full continuation" (everything in the stack) of a
+** previously interrupted coroutine until the stack is empty (or another
+** interruption long-jumps out of the loop). If the coroutine is
+** recovering from an error, 'ud' points to the error status, which must
+** be passed to the first continuation function (otherwise the default
+** status is LUA_YIELD).
+*/
+static void unroll (lua_State *L, void *ud) {
+  CallInfo *ci;
+  if (ud != NULL)  /* error status? */
+    finishCcall(L, *(int *)ud);  /* finish 'lua_pcallk' callee */
+  while ((ci = L->ci) != &L->base_ci) {  /* something in the stack */
+    if (!isLua(ci))  /* C function? */
+      finishCcall(L, LUA_YIELD);  /* complete its execution */
+    else {  /* Lua function */
+      luaV_finishOp(L);  /* finish interrupted instruction */
+      luaV_execute(L, ci);  /* execute down to higher C 'boundary' */
+    }
+  }
+}
+
+
+/*
+** Try to find a suspended protected call (a "recover point") for the
+** given thread.
+*/
+static CallInfo *findpcall (lua_State *L) {
+  CallInfo *ci;
+  for (ci = L->ci; ci != NULL; ci = ci->previous) {  /* search for a pcall */
+    if (ci->callstatus & CIST_YPCALL)
+      return ci;
+  }
+  return NULL;  /* no pending pcall */
+}
+
+
+/*
+** Recovers from an error in a coroutine. Finds a recover point (if
+** there is one) and completes the execution of the interrupted
+** 'luaD_pcall'. If there is no recover point, returns zero.
+*/
+static int recover (lua_State *L, int status) {
+  StkId oldtop;
+  CallInfo *ci = findpcall(L);
+  if (ci == NULL) return 0;  /* no recovery point */
+  /* "finish" luaD_pcall */
+  oldtop = restorestack(L, ci->u2.funcidx);
+  luaF_close(L, oldtop, status);  /* may change the stack */
+  oldtop = restorestack(L, ci->u2.funcidx);
+  luaD_seterrorobj(L, status, oldtop);
+  L->ci = ci;
+  L->allowhook = getoah(ci->callstatus);  /* restore original 'allowhook' */
+  luaD_shrinkstack(L);
+  L->errfunc = ci->u.c.old_errfunc;
+  return 1;  /* continue running the coroutine */
+}
+
+
+/*
+** Signal an error in the call to 'lua_resume', not in the execution
+** of the coroutine itself. (Such errors should not be handled by any
+** coroutine error handler and should not kill the coroutine.)
+*/
+static int resume_error (lua_State *L, const char *msg, int narg) {
+  L->top -= narg;  /* remove args from the stack */
+  setsvalue2s(L, L->top, luaS_new(L, msg));  /* push error message */
+  api_incr_top(L);
+  lua_unlock(L);
+  return LUA_ERRRUN;
+}
+
+
+/*
+** Do the work for 'lua_resume' in protected mode. Most of the work
+** depends on the status of the coroutine: initial state, suspended
+** inside a hook, or regularly suspended (optionally with a continuation
+** function), plus erroneous cases: non-suspended coroutine or dead
+** coroutine.
+*/
+static void resume (lua_State *L, void *ud) {
+  int n = *(cast(int*, ud));  /* number of arguments */
+  StkId firstArg = L->top - n;  /* first argument */
+  CallInfo *ci = L->ci;
+  if (L->status == LUA_OK) {  /* starting a coroutine? */
+    luaD_call(L, firstArg - 1, LUA_MULTRET);
+  }
+  else {  /* resuming from previous yield */
+    lua_assert(L->status == LUA_YIELD);
+    L->status = LUA_OK;  /* mark that it is running (again) */
+    if (isLua(ci))  /* yielded inside a hook? */
+      luaV_execute(L, ci);  /* just continue running Lua code */
+    else {  /* 'common' yield */
+      if (ci->u.c.k != NULL) {  /* does it have a continuation function? */
+        lua_unlock(L);
+        n = (*ci->u.c.k)(L, LUA_YIELD, ci->u.c.ctx); /* call continuation */
+        lua_lock(L);
+        api_checknelems(L, n);
+      }
+      luaD_poscall(L, ci, n);  /* finish 'luaD_call' */
+    }
+    unroll(L, NULL);  /* run continuation */
+  }
+}
+
+LUA_API int lua_resume (lua_State *L, lua_State *from, int nargs,
+                                      int *nresults) {
+  int status;
+  lua_lock(L);
+  if (L->status == LUA_OK) {  /* may be starting a coroutine */
+    if (L->ci != &L->base_ci)  /* not in base level? */
+      return resume_error(L, "cannot resume non-suspended coroutine", nargs);
+    else if (L->top - (L->ci->func + 1) == nargs)  /* no function? */
+      return resume_error(L, "cannot resume dead coroutine", nargs);
+  }
+  else if (L->status != LUA_YIELD)  /* ended with errors? */
+    return resume_error(L, "cannot resume dead coroutine", nargs);
+  if (from == NULL)
+    L->nCcalls = CSTACKTHREAD;
+  else  /* correct 'nCcalls' for this thread */
+    L->nCcalls = getCcalls(from) + from->nci - L->nci - CSTACKCF;
+  if (L->nCcalls <= CSTACKERR)
+    return resume_error(L, "C stack overflow", nargs);
+  luai_userstateresume(L, nargs);
+  api_checknelems(L, (L->status == LUA_OK) ? nargs + 1 : nargs);
+  status = luaD_rawrunprotected(L, resume, &nargs);
+   /* continue running after recoverable errors */
+  while (errorstatus(status) && recover(L, status)) {
+    /* unroll continuation */
+    status = luaD_rawrunprotected(L, unroll, &status);
+  }
+  if (likely(!errorstatus(status)))
+    lua_assert(status == L->status);  /* normal end or yield */
+  else {  /* unrecoverable error */
+    L->status = cast_byte(status);  /* mark thread as 'dead' */
+    luaD_seterrorobj(L, status, L->top);  /* push error message */
+    L->ci->top = L->top;
+  }
+  *nresults = (status == LUA_YIELD) ? L->ci->u2.nyield
+                                    : cast_int(L->top - (L->ci->func + 1));
+  lua_unlock(L);
+  return status;
+}
+
+
+LUA_API int lua_isyieldable (lua_State *L) {
+  return yieldable(L);
+}
+
+
+LUA_API int lua_yieldk (lua_State *L, int nresults, lua_KContext ctx,
+                        lua_KFunction k) {
+  CallInfo *ci = L->ci;
+  luai_userstateyield(L, nresults);
+  lua_lock(L);
+  api_checknelems(L, nresults);
+  if (unlikely(!yieldable(L))) {
+    if (L != G(L)->mainthread)
+      luaG_runerror(L, "attempt to yield across a C-call boundary");
+    else
+      luaG_runerror(L, "attempt to yield from outside a coroutine");
+  }
+  L->status = LUA_YIELD;
+  if (isLua(ci)) {  /* inside a hook? */
+    lua_assert(!isLuacode(ci));
+    api_check(L, k == NULL, "hooks cannot continue after yielding");
+    ci->u2.nyield = 0;  /* no results */
+  }
+  else {
+    if ((ci->u.c.k = k) != NULL)  /* is there a continuation? */
+      ci->u.c.ctx = ctx;  /* save context */
+    ci->u2.nyield = nresults;  /* save number of results */
+    luaD_throw(L, LUA_YIELD);
+  }
+  lua_assert(ci->callstatus & CIST_HOOKED);  /* must be inside a hook */
+  lua_unlock(L);
+  return 0;  /* return to 'luaD_hook' */
+}
+
+
+/*
+** Call the C function 'func' in protected mode, restoring basic
+** thread information ('allowhook', etc.) and in particular
+** its stack level in case of errors.
+*/
+int luaD_pcall (lua_State *L, Pfunc func, void *u,
+                ptrdiff_t old_top, ptrdiff_t ef) {
+  int status;
+  CallInfo *old_ci = L->ci;
+  lu_byte old_allowhooks = L->allowhook;
+  ptrdiff_t old_errfunc = L->errfunc;
+  L->errfunc = ef;
+  status = luaD_rawrunprotected(L, func, u);
+  if (unlikely(status != LUA_OK)) {  /* an error occurred? */
+    StkId oldtop = restorestack(L, old_top);
+    L->ci = old_ci;
+    L->allowhook = old_allowhooks;
+    status = luaF_close(L, oldtop, status);
+    oldtop = restorestack(L, old_top);  /* previous call may change stack */
+    luaD_seterrorobj(L, status, oldtop);
+    luaD_shrinkstack(L);
+  }
+  L->errfunc = old_errfunc;
+  return status;
+}
+
+
+
+/*
+** Execute a protected parser.
+*/
+struct SParser {  /* data to 'f_parser' */
+  ZIO *z;
+  Mbuffer buff;  /* dynamic structure used by the scanner */
+  Dyndata dyd;  /* dynamic structures used by the parser */
+  const char *mode;
+  const char *name;
+};
+
+
+static void checkmode (lua_State *L, const char *mode, const char *x) {
+  if (mode && strchr(mode, x[0]) == NULL) {
+    luaO_pushfstring(L,
+       "attempt to load a %s chunk (mode is '%s')", x, mode);
+    luaD_throw(L, LUA_ERRSYNTAX);
+  }
+}
+
+
+static void f_parser (lua_State *L, void *ud) {
+  LClosure *cl;
+  struct SParser *p = cast(struct SParser *, ud);
+  int c = zgetc(p->z);  /* read first character */
+  if (c == LUA_SIGNATURE[0]) {
+    checkmode(L, p->mode, "binary");
+    cl = luaU_undump(L, p->z, p->name);
+  }
+  else {
+    checkmode(L, p->mode, "text");
+    cl = luaY_parser(L, p->z, &p->buff, &p->dyd, p->name, c);
+  }
+  lua_assert(cl->nupvalues == cl->p->sizeupvalues);
+  luaF_initupvals(L, cl);
+}
+
+
+int luaD_protectedparser (lua_State *L, ZIO *z, const char *name,
+                                        const char *mode) {
+  struct SParser p;
+  int status;
+  incnny(L);  /* cannot yield during parsing */
+  p.z = z; p.name = name; p.mode = mode;
+  p.dyd.actvar.arr = NULL; p.dyd.actvar.size = 0;
+  p.dyd.gt.arr = NULL; p.dyd.gt.size = 0;
+  p.dyd.label.arr = NULL; p.dyd.label.size = 0;
+  luaZ_initbuffer(L, &p.buff);
+  status = luaD_pcall(L, f_parser, &p, savestack(L, L->top), L->errfunc);
+  luaZ_freebuffer(L, &p.buff);
+  luaM_freearray(L, p.dyd.actvar.arr, p.dyd.actvar.size);
+  luaM_freearray(L, p.dyd.gt.arr, p.dyd.gt.size);
+  luaM_freearray(L, p.dyd.label.arr, p.dyd.label.size);
+  decnny(L);
+  return status;
+}
+
+
diff --git a/test/external/lua-5.4.0/src/ldo.h b/test/external/lua-5.4.0/src/ldo.h
new file mode 100644
index 0000000..7760f85
--- /dev/null
+++ b/test/external/lua-5.4.0/src/ldo.h
@@ -0,0 +1,75 @@
+/*
+** $Id: ldo.h $
+** Stack and Call structure of Lua
+** See Copyright Notice in lua.h
+*/
+
+#ifndef ldo_h
+#define ldo_h
+
+
+#include "lobject.h"
+#include "lstate.h"
+#include "lzio.h"
+
+
+/*
+** Macro to check stack size and grow stack if needed.  Parameters
+** 'pre'/'pos' allow the macro to preserve a pointer into the
+** stack across reallocations, doing the work only when needed.
+** 'condmovestack' is used in heavy tests to force a stack reallocation
+** at every check.
+*/
+#define luaD_checkstackaux(L,n,pre,pos)  \
+	if (L->stack_last - L->top <= (n)) \
+	  { pre; luaD_growstack(L, n, 1); pos; } \
+        else { condmovestack(L,pre,pos); }
+
+/* In general, 'pre'/'pos' are empty (nothing to save) */
+#define luaD_checkstack(L,n)	luaD_checkstackaux(L,n,(void)0,(void)0)
+
+
+
+#define savestack(L,p)		((char *)(p) - (char *)L->stack)
+#define restorestack(L,n)	((StkId)((char *)L->stack + (n)))
+
+
+/* macro to check stack size, preserving 'p' */
+#define checkstackp(L,n,p)  \
+  luaD_checkstackaux(L, n, \
+    ptrdiff_t t__ = savestack(L, p);  /* save 'p' */ \
+    luaC_checkGC(L),  /* stack grow uses memory */ \
+    p = restorestack(L, t__))  /* 'pos' part: restore 'p' */
+
+
+/* macro to check stack size and GC */
+#define checkstackGC(L,fsize)  \
+	luaD_checkstackaux(L, (fsize), (void)0, luaC_checkGC(L))
+
+
+/* type of protected functions, to be ran by 'runprotected' */
+typedef void (*Pfunc) (lua_State *L, void *ud);
+
+LUAI_FUNC void luaD_seterrorobj (lua_State *L, int errcode, StkId oldtop);
+LUAI_FUNC int luaD_protectedparser (lua_State *L, ZIO *z, const char *name,
+                                                  const char *mode);
+LUAI_FUNC void luaD_hook (lua_State *L, int event, int line,
+                                        int fTransfer, int nTransfer);
+LUAI_FUNC void luaD_hookcall (lua_State *L, CallInfo *ci);
+LUAI_FUNC void luaD_pretailcall (lua_State *L, CallInfo *ci, StkId func, int n);
+LUAI_FUNC void luaD_call (lua_State *L, StkId func, int nResults);
+LUAI_FUNC void luaD_callnoyield (lua_State *L, StkId func, int nResults);
+LUAI_FUNC void luaD_tryfuncTM (lua_State *L, StkId func);
+LUAI_FUNC int luaD_pcall (lua_State *L, Pfunc func, void *u,
+                                        ptrdiff_t oldtop, ptrdiff_t ef);
+LUAI_FUNC void luaD_poscall (lua_State *L, CallInfo *ci, int nres);
+LUAI_FUNC int luaD_reallocstack (lua_State *L, int newsize, int raiseerror);
+LUAI_FUNC int luaD_growstack (lua_State *L, int n, int raiseerror);
+LUAI_FUNC void luaD_shrinkstack (lua_State *L);
+LUAI_FUNC void luaD_inctop (lua_State *L);
+
+LUAI_FUNC l_noret luaD_throw (lua_State *L, int errcode);
+LUAI_FUNC int luaD_rawrunprotected (lua_State *L, Pfunc f, void *ud);
+
+#endif
+
diff --git a/test/external/lua-5.4.0/src/ldump.c b/test/external/lua-5.4.0/src/ldump.c
new file mode 100644
index 0000000..f848b66
--- /dev/null
+++ b/test/external/lua-5.4.0/src/ldump.c
@@ -0,0 +1,226 @@
+/*
+** $Id: ldump.c $
+** save precompiled Lua chunks
+** See Copyright Notice in lua.h
+*/
+
+#define ldump_c
+#define LUA_CORE
+
+#include "lprefix.h"
+
+
+#include <stddef.h>
+
+#include "lua.h"
+
+#include "lobject.h"
+#include "lstate.h"
+#include "lundump.h"
+
+
+typedef struct {
+  lua_State *L;
+  lua_Writer writer;
+  void *data;
+  int strip;
+  int status;
+} DumpState;
+
+
+/*
+** All high-level dumps go through dumpVector; you can change it to
+** change the endianness of the result
+*/
+#define dumpVector(D,v,n)	dumpBlock(D,v,(n)*sizeof((v)[0]))
+
+#define dumpLiteral(D, s)	dumpBlock(D,s,sizeof(s) - sizeof(char))
+
+
+static void dumpBlock (DumpState *D, const void *b, size_t size) {
+  if (D->status == 0 && size > 0) {
+    lua_unlock(D->L);
+    D->status = (*D->writer)(D->L, b, size, D->data);
+    lua_lock(D->L);
+  }
+}
+
+
+#define dumpVar(D,x)		dumpVector(D,&x,1)
+
+
+static void dumpByte (DumpState *D, int y) {
+  lu_byte x = (lu_byte)y;
+  dumpVar(D, x);
+}
+
+
+/* dumpInt Buff Size */
+#define DIBS    ((sizeof(size_t) * 8 / 7) + 1)
+
+static void dumpSize (DumpState *D, size_t x) {
+  lu_byte buff[DIBS];
+  int n = 0;
+  do {
+    buff[DIBS - (++n)] = x & 0x7f;  /* fill buffer in reverse order */
+    x >>= 7;
+  } while (x != 0);
+  buff[DIBS - 1] |= 0x80;  /* mark last byte */
+  dumpVector(D, buff + DIBS - n, n);
+}
+
+
+static void dumpInt (DumpState *D, int x) {
+  dumpSize(D, x);
+}
+
+
+static void dumpNumber (DumpState *D, lua_Number x) {
+  dumpVar(D, x);
+}
+
+
+static void dumpInteger (DumpState *D, lua_Integer x) {
+  dumpVar(D, x);
+}
+
+
+static void dumpString (DumpState *D, const TString *s) {
+  if (s == NULL)
+    dumpSize(D, 0);
+  else {
+    size_t size = tsslen(s);
+    const char *str = getstr(s);
+    dumpSize(D, size + 1);
+    dumpVector(D, str, size);
+  }
+}
+
+
+static void dumpCode (DumpState *D, const Proto *f) {
+  dumpInt(D, f->sizecode);
+  dumpVector(D, f->code, f->sizecode);
+}
+
+
+static void dumpFunction(DumpState *D, const Proto *f, TString *psource);
+
+static void dumpConstants (DumpState *D, const Proto *f) {
+  int i;
+  int n = f->sizek;
+  dumpInt(D, n);
+  for (i = 0; i < n; i++) {
+    const TValue *o = &f->k[i];
+    int tt = ttypetag(o);
+    dumpByte(D, tt);
+    switch (tt) {
+      case LUA_VNUMFLT:
+        dumpNumber(D, fltvalue(o));
+        break;
+      case LUA_VNUMINT:
+        dumpInteger(D, ivalue(o));
+        break;
+      case LUA_VSHRSTR:
+      case LUA_VLNGSTR:
+        dumpString(D, tsvalue(o));
+        break;
+      default:
+        lua_assert(tt == LUA_VNIL || tt == LUA_VFALSE || tt == LUA_VTRUE);
+    }
+  }
+}
+
+
+static void dumpProtos (DumpState *D, const Proto *f) {
+  int i;
+  int n = f->sizep;
+  dumpInt(D, n);
+  for (i = 0; i < n; i++)
+    dumpFunction(D, f->p[i], f->source);
+}
+
+
+static void dumpUpvalues (DumpState *D, const Proto *f) {
+  int i, n = f->sizeupvalues;
+  dumpInt(D, n);
+  for (i = 0; i < n; i++) {
+    dumpByte(D, f->upvalues[i].instack);
+    dumpByte(D, f->upvalues[i].idx);
+    dumpByte(D, f->upvalues[i].kind);
+  }
+}
+
+
+static void dumpDebug (DumpState *D, const Proto *f) {
+  int i, n;
+  n = (D->strip) ? 0 : f->sizelineinfo;
+  dumpInt(D, n);
+  dumpVector(D, f->lineinfo, n);
+  n = (D->strip) ? 0 : f->sizeabslineinfo;
+  dumpInt(D, n);
+  for (i = 0; i < n; i++) {
+    dumpInt(D, f->abslineinfo[i].pc);
+    dumpInt(D, f->abslineinfo[i].line);
+  }
+  n = (D->strip) ? 0 : f->sizelocvars;
+  dumpInt(D, n);
+  for (i = 0; i < n; i++) {
+    dumpString(D, f->locvars[i].varname);
+    dumpInt(D, f->locvars[i].startpc);
+    dumpInt(D, f->locvars[i].endpc);
+  }
+  n = (D->strip) ? 0 : f->sizeupvalues;
+  dumpInt(D, n);
+  for (i = 0; i < n; i++)
+    dumpString(D, f->upvalues[i].name);
+}
+
+
+static void dumpFunction (DumpState *D, const Proto *f, TString *psource) {
+  if (D->strip || f->source == psource)
+    dumpString(D, NULL);  /* no debug info or same source as its parent */
+  else
+    dumpString(D, f->source);
+  dumpInt(D, f->linedefined);
+  dumpInt(D, f->lastlinedefined);
+  dumpByte(D, f->numparams);
+  dumpByte(D, f->is_vararg);
+  dumpByte(D, f->maxstacksize);
+  dumpCode(D, f);
+  dumpConstants(D, f);
+  dumpUpvalues(D, f);
+  dumpProtos(D, f);
+  dumpDebug(D, f);
+}
+
+
+static void dumpHeader (DumpState *D) {
+  dumpLiteral(D, LUA_SIGNATURE);
+  dumpByte(D, LUAC_VERSION);
+  dumpByte(D, LUAC_FORMAT);
+  dumpLiteral(D, LUAC_DATA);
+  dumpByte(D, sizeof(Instruction));
+  dumpByte(D, sizeof(lua_Integer));
+  dumpByte(D, sizeof(lua_Number));
+  dumpInteger(D, LUAC_INT);
+  dumpNumber(D, LUAC_NUM);
+}
+
+
+/*
+** dump Lua function as precompiled chunk
+*/
+int luaU_dump(lua_State *L, const Proto *f, lua_Writer w, void *data,
+              int strip) {
+  DumpState D;
+  D.L = L;
+  D.writer = w;
+  D.data = data;
+  D.strip = strip;
+  D.status = 0;
+  dumpHeader(&D);
+  dumpByte(&D, f->sizeupvalues);
+  dumpFunction(&D, f, NULL);
+  return D.status;
+}
+
diff --git a/test/external/lua-5.4.0/src/lfunc.c b/test/external/lua-5.4.0/src/lfunc.c
new file mode 100644
index 0000000..10100e5
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lfunc.c
@@ -0,0 +1,299 @@
+/*
+** $Id: lfunc.c $
+** Auxiliary functions to manipulate prototypes and closures
+** See Copyright Notice in lua.h
+*/
+
+#define lfunc_c
+#define LUA_CORE
+
+#include "lprefix.h"
+
+
+#include <stddef.h>
+
+#include "lua.h"
+
+#include "ldebug.h"
+#include "ldo.h"
+#include "lfunc.h"
+#include "lgc.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lstate.h"
+
+
+
+CClosure *luaF_newCclosure (lua_State *L, int nupvals) {
+  GCObject *o = luaC_newobj(L, LUA_VCCL, sizeCclosure(nupvals));
+  CClosure *c = gco2ccl(o);
+  c->nupvalues = cast_byte(nupvals);
+  return c;
+}
+
+
+LClosure *luaF_newLclosure (lua_State *L, int nupvals) {
+  GCObject *o = luaC_newobj(L, LUA_VLCL, sizeLclosure(nupvals));
+  LClosure *c = gco2lcl(o);
+  c->p = NULL;
+  c->nupvalues = cast_byte(nupvals);
+  while (nupvals--) c->upvals[nupvals] = NULL;
+  return c;
+}
+
+
+/*
+** fill a closure with new closed upvalues
+*/
+void luaF_initupvals (lua_State *L, LClosure *cl) {
+  int i;
+  for (i = 0; i < cl->nupvalues; i++) {
+    GCObject *o = luaC_newobj(L, LUA_VUPVAL, sizeof(UpVal));
+    UpVal *uv = gco2upv(o);
+    uv->v = &uv->u.value;  /* make it closed */
+    setnilvalue(uv->v);
+    cl->upvals[i] = uv;
+    luaC_objbarrier(L, cl, o);
+  }
+}
+
+
+/*
+** Create a new upvalue at the given level, and link it to the list of
+** open upvalues of 'L' after entry 'prev'.
+**/
+static UpVal *newupval (lua_State *L, int tbc, StkId level, UpVal **prev) {
+  GCObject *o = luaC_newobj(L, LUA_VUPVAL, sizeof(UpVal));
+  UpVal *uv = gco2upv(o);
+  UpVal *next = *prev;
+  uv->v = s2v(level);  /* current value lives in the stack */
+  uv->tbc = tbc;
+  uv->u.open.next = next;  /* link it to list of open upvalues */
+  uv->u.open.previous = prev;
+  if (next)
+    next->u.open.previous = &uv->u.open.next;
+  *prev = uv;
+  if (!isintwups(L)) {  /* thread not in list of threads with upvalues? */
+    L->twups = G(L)->twups;  /* link it to the list */
+    G(L)->twups = L;
+  }
+  return uv;
+}
+
+
+/*
+** Find and reuse, or create if it does not exist, an upvalue
+** at the given level.
+*/
+UpVal *luaF_findupval (lua_State *L, StkId level) {
+  UpVal **pp = &L->openupval;
+  UpVal *p;
+  lua_assert(isintwups(L) || L->openupval == NULL);
+  while ((p = *pp) != NULL && uplevel(p) >= level) {  /* search for it */
+    lua_assert(!isdead(G(L), p));
+    if (uplevel(p) == level)  /* corresponding upvalue? */
+      return p;  /* return it */
+    pp = &p->u.open.next;
+  }
+  /* not found: create a new upvalue after 'pp' */
+  return newupval(L, 0, level, pp);
+}
+
+
+static void callclose (lua_State *L, void *ud) {
+  UNUSED(ud);
+  luaD_callnoyield(L, L->top - 3, 0);
+}
+
+
+/*
+** Prepare closing method plus its arguments for object 'obj' with
+** error message 'err'. (This function assumes EXTRA_STACK.)
+*/
+static int prepclosingmethod (lua_State *L, TValue *obj, TValue *err) {
+  StkId top = L->top;
+  const TValue *tm = luaT_gettmbyobj(L, obj, TM_CLOSE);
+  if (ttisnil(tm))  /* no metamethod? */
+    return 0;  /* nothing to call */
+  setobj2s(L, top, tm);  /* will call metamethod... */
+  setobj2s(L, top + 1, obj);  /* with 'self' as the 1st argument */
+  setobj2s(L, top + 2, err);  /* and error msg. as 2nd argument */
+  L->top = top + 3;  /* add function and arguments */
+  return 1;
+}
+
+
+/*
+** Raise an error with message 'msg', inserting the name of the
+** local variable at position 'level' in the stack.
+*/
+static void varerror (lua_State *L, StkId level, const char *msg) {
+  int idx = cast_int(level - L->ci->func);
+  const char *vname = luaG_findlocal(L, L->ci, idx, NULL);
+  if (vname == NULL) vname = "?";
+  luaG_runerror(L, msg, vname);
+}
+
+
+/*
+** Prepare and call a closing method. If status is OK, code is still
+** inside the original protected call, and so any error will be handled
+** there. Otherwise, a previous error already activated the original
+** protected call, and so the call to the closing method must be
+** protected here. (A status == CLOSEPROTECT behaves like a previous
+** error, to also run the closing method in protected mode).
+** If status is OK, the call to the closing method will be pushed
+** at the top of the stack. Otherwise, values are pushed after
+** the 'level' of the upvalue being closed, as everything after
+** that won't be used again.
+*/
+static int callclosemth (lua_State *L, StkId level, int status) {
+  TValue *uv = s2v(level);  /* value being closed */
+  if (likely(status == LUA_OK)) {
+    if (prepclosingmethod(L, uv, &G(L)->nilvalue))  /* something to call? */
+      callclose(L, NULL);  /* call closing method */
+    else if (!l_isfalse(uv))  /* non-closable non-false value? */
+      varerror(L, level, "attempt to close non-closable variable '%s'");
+  }
+  else {  /* must close the object in protected mode */
+    ptrdiff_t oldtop;
+    level++;  /* space for error message */
+    oldtop = savestack(L, level + 1);  /* top will be after that */
+    luaD_seterrorobj(L, status, level);  /* set error message */
+    if (prepclosingmethod(L, uv, s2v(level))) {  /* something to call? */
+      int newstatus = luaD_pcall(L, callclose, NULL, oldtop, 0);
+      if (newstatus != LUA_OK && status == CLOSEPROTECT)  /* first error? */
+        status = newstatus;  /* this will be the new error */
+      else {
+        if (newstatus != LUA_OK)  /* suppressed error? */
+          luaE_warnerror(L, "__close metamethod");
+        /* leave original error (or nil) on top */
+        L->top = restorestack(L, oldtop);
+      }
+    }
+    /* else no metamethod; ignore this case and keep original error */
+  }
+  return status;
+}
+
+
+/*
+** Try to create a to-be-closed upvalue
+** (can raise a memory-allocation error)
+*/
+static void trynewtbcupval (lua_State *L, void *ud) {
+  newupval(L, 1, cast(StkId, ud), &L->openupval);
+}
+
+
+/*
+** Create a to-be-closed upvalue. If there is a memory error
+** when creating the upvalue, the closing method must be called here,
+** as there is no upvalue to call it later.
+*/
+void luaF_newtbcupval (lua_State *L, StkId level) {
+  TValue *obj = s2v(level);
+  lua_assert(L->openupval == NULL || uplevel(L->openupval) < level);
+  if (!l_isfalse(obj)) {  /* false doesn't need to be closed */
+    int status;
+    const TValue *tm = luaT_gettmbyobj(L, obj, TM_CLOSE);
+    if (ttisnil(tm))  /* no metamethod? */
+      varerror(L, level, "variable '%s' got a non-closable value");
+    status = luaD_rawrunprotected(L, trynewtbcupval, level);
+    if (unlikely(status != LUA_OK)) {  /* memory error creating upvalue? */
+      lua_assert(status == LUA_ERRMEM);
+      luaD_seterrorobj(L, LUA_ERRMEM, level + 1);  /* save error message */
+      /* next call must succeed, as object is closable */
+      prepclosingmethod(L, s2v(level), s2v(level + 1));
+      callclose(L, NULL);  /* call closing method */
+      luaD_throw(L, LUA_ERRMEM);  /* throw memory error */
+    }
+  }
+}
+
+
+void luaF_unlinkupval (UpVal *uv) {
+  lua_assert(upisopen(uv));
+  *uv->u.open.previous = uv->u.open.next;
+  if (uv->u.open.next)
+    uv->u.open.next->u.open.previous = uv->u.open.previous;
+}
+
+
+int luaF_close (lua_State *L, StkId level, int status) {
+  UpVal *uv;
+  while ((uv = L->openupval) != NULL && uplevel(uv) >= level) {
+    TValue *slot = &uv->u.value;  /* new position for value */
+    lua_assert(uplevel(uv) < L->top);
+    if (uv->tbc && status != NOCLOSINGMETH) {
+      /* must run closing method, which may change the stack */
+      ptrdiff_t levelrel = savestack(L, level);
+      status = callclosemth(L, uplevel(uv), status);
+      level = restorestack(L, levelrel);
+    }
+    luaF_unlinkupval(uv);
+    setobj(L, slot, uv->v);  /* move value to upvalue slot */
+    uv->v = slot;  /* now current value lives here */
+    if (!iswhite(uv))
+      gray2black(uv);  /* closed upvalues cannot be gray */
+    luaC_barrier(L, uv, slot);
+  }
+  return status;
+}
+
+
+Proto *luaF_newproto (lua_State *L) {
+  GCObject *o = luaC_newobj(L, LUA_VPROTO, sizeof(Proto));
+  Proto *f = gco2p(o);
+  f->k = NULL;
+  f->sizek = 0;
+  f->p = NULL;
+  f->sizep = 0;
+  f->code = NULL;
+  f->sizecode = 0;
+  f->lineinfo = NULL;
+  f->sizelineinfo = 0;
+  f->abslineinfo = NULL;
+  f->sizeabslineinfo = 0;
+  f->upvalues = NULL;
+  f->sizeupvalues = 0;
+  f->numparams = 0;
+  f->is_vararg = 0;
+  f->maxstacksize = 0;
+  f->locvars = NULL;
+  f->sizelocvars = 0;
+  f->linedefined = 0;
+  f->lastlinedefined = 0;
+  f->source = NULL;
+  return f;
+}
+
+
+void luaF_freeproto (lua_State *L, Proto *f) {
+  luaM_freearray(L, f->code, f->sizecode);
+  luaM_freearray(L, f->p, f->sizep);
+  luaM_freearray(L, f->k, f->sizek);
+  luaM_freearray(L, f->lineinfo, f->sizelineinfo);
+  luaM_freearray(L, f->abslineinfo, f->sizeabslineinfo);
+  luaM_freearray(L, f->locvars, f->sizelocvars);
+  luaM_freearray(L, f->upvalues, f->sizeupvalues);
+  luaM_free(L, f);
+}
+
+
+/*
+** Look for n-th local variable at line 'line' in function 'func'.
+** Returns NULL if not found.
+*/
+const char *luaF_getlocalname (const Proto *f, int local_number, int pc) {
+  int i;
+  for (i = 0; i<f->sizelocvars && f->locvars[i].startpc <= pc; i++) {
+    if (pc < f->locvars[i].endpc) {  /* is variable active? */
+      local_number--;
+      if (local_number == 0)
+        return getstr(f->locvars[i].varname);
+    }
+  }
+  return NULL;  /* not found */
+}
+
diff --git a/test/external/lua-5.4.0/src/lfunc.h b/test/external/lua-5.4.0/src/lfunc.h
new file mode 100644
index 0000000..8d6f965
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lfunc.h
@@ -0,0 +1,69 @@
+/*
+** $Id: lfunc.h $
+** Auxiliary functions to manipulate prototypes and closures
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lfunc_h
+#define lfunc_h
+
+
+#include "lobject.h"
+
+
+#define sizeCclosure(n)	(cast_int(offsetof(CClosure, upvalue)) + \
+                         cast_int(sizeof(TValue)) * (n))
+
+#define sizeLclosure(n)	(cast_int(offsetof(LClosure, upvals)) + \
+                         cast_int(sizeof(TValue *)) * (n))
+
+
+/* test whether thread is in 'twups' list */
+#define isintwups(L)	(L->twups != L)
+
+
+/*
+** maximum number of upvalues in a closure (both C and Lua). (Value
+** must fit in a VM register.)
+*/
+#define MAXUPVAL	255
+
+
+#define upisopen(up)	((up)->v != &(up)->u.value)
+
+
+#define uplevel(up)	check_exp(upisopen(up), cast(StkId, (up)->v))
+
+
+/*
+** maximum number of misses before giving up the cache of closures
+** in prototypes
+*/
+#define MAXMISS		10
+
+
+/*
+** Special "status" for 'luaF_close'
+*/
+
+/* close upvalues without running their closing methods */
+#define NOCLOSINGMETH	(-1)
+
+/* close upvalues running all closing methods in protected mode */
+#define CLOSEPROTECT	(-2)
+
+
+LUAI_FUNC Proto *luaF_newproto (lua_State *L);
+LUAI_FUNC CClosure *luaF_newCclosure (lua_State *L, int nupvals);
+LUAI_FUNC LClosure *luaF_newLclosure (lua_State *L, int nupvals);
+LUAI_FUNC void luaF_initupvals (lua_State *L, LClosure *cl);
+LUAI_FUNC UpVal *luaF_findupval (lua_State *L, StkId level);
+LUAI_FUNC void luaF_newtbcupval (lua_State *L, StkId level);
+LUAI_FUNC int luaF_close (lua_State *L, StkId level, int status);
+LUAI_FUNC void luaF_unlinkupval (UpVal *uv);
+LUAI_FUNC void luaF_freeproto (lua_State *L, Proto *f);
+LUAI_FUNC const char *luaF_getlocalname (const Proto *func, int local_number,
+                                         int pc);
+
+
+#endif
diff --git a/test/external/lua-5.4.0/src/lgc.c b/test/external/lua-5.4.0/src/lgc.c
new file mode 100644
index 0000000..f26c921
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lgc.c
@@ -0,0 +1,1616 @@
+/*
+** $Id: lgc.c $
+** Garbage Collector
+** See Copyright Notice in lua.h
+*/
+
+#define lgc_c
+#define LUA_CORE
+
+#include "lprefix.h"
+
+#include <stdio.h>
+#include <string.h>
+
+
+#include "lua.h"
+
+#include "ldebug.h"
+#include "ldo.h"
+#include "lfunc.h"
+#include "lgc.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "ltm.h"
+
+
+/*
+** Maximum number of elements to sweep in each single step.
+** (Large enough to dissipate fixed overheads but small enough
+** to allow small steps for the collector.)
+*/
+#define GCSWEEPMAX	100
+
+/*
+** Maximum number of finalizers to call in each single step.
+*/
+#define GCFINMAX	10
+
+
+/*
+** Cost of calling one finalizer.
+*/
+#define GCFINALIZECOST	50
+
+
+/*
+** The equivalent, in bytes, of one unit of "work" (visiting a slot,
+** sweeping an object, etc.)
+*/
+#define WORK2MEM	sizeof(TValue)
+
+
+/*
+** macro to adjust 'pause': 'pause' is actually used like
+** 'pause / PAUSEADJ' (value chosen by tests)
+*/
+#define PAUSEADJ		100
+
+
+/* mask to erase all color bits (plus gen. related stuff) */
+#define maskcolors	(~(bitmask(BLACKBIT) | WHITEBITS | AGEBITS))
+
+
+/* macro to erase all color bits then sets only the current white bit */
+#define makewhite(g,x)	\
+ (x->marked = cast_byte((x->marked & maskcolors) | luaC_white(g)))
+
+#define white2gray(x)	resetbits(x->marked, WHITEBITS)
+#define black2gray(x)	resetbit(x->marked, BLACKBIT)
+
+
+#define valiswhite(x)   (iscollectable(x) && iswhite(gcvalue(x)))
+
+#define keyiswhite(n)   (keyiscollectable(n) && iswhite(gckey(n)))
+
+
+#define checkconsistency(obj)  \
+  lua_longassert(!iscollectable(obj) || righttt(obj))
+
+/*
+** Protected access to objects in values
+*/
+#define gcvalueN(o)     (iscollectable(o) ? gcvalue(o) : NULL)
+
+
+#define markvalue(g,o) { checkconsistency(o); \
+  if (valiswhite(o)) reallymarkobject(g,gcvalue(o)); }
+
+#define markkey(g, n)	{ if keyiswhite(n) reallymarkobject(g,gckey(n)); }
+
+#define markobject(g,t)	{ if (iswhite(t)) reallymarkobject(g, obj2gco(t)); }
+
+/*
+** mark an object that can be NULL (either because it is really optional,
+** or it was stripped as debug info, or inside an uncompleted structure)
+*/
+#define markobjectN(g,t)	{ if (t) markobject(g,t); }
+
+static void reallymarkobject (global_State *g, GCObject *o);
+static lu_mem atomic (lua_State *L);
+static void entersweep (lua_State *L);
+
+
+/*
+** {======================================================
+** Generic functions
+** =======================================================
+*/
+
+
+/*
+** one after last element in a hash array
+*/
+#define gnodelast(h)	gnode(h, cast_sizet(sizenode(h)))
+
+
+static GCObject **getgclist (GCObject *o) {
+  switch (o->tt) {
+    case LUA_VTABLE: return &gco2t(o)->gclist;
+    case LUA_VLCL: return &gco2lcl(o)->gclist;
+    case LUA_VCCL: return &gco2ccl(o)->gclist;
+    case LUA_VTHREAD: return &gco2th(o)->gclist;
+    case LUA_VPROTO: return &gco2p(o)->gclist;
+    case LUA_VUSERDATA: {
+      Udata *u = gco2u(o);
+      lua_assert(u->nuvalue > 0);
+      return &u->gclist;
+    }
+    default: lua_assert(0); return 0;
+  }
+}
+
+
+/*
+** Link a collectable object 'o' with a known type into list pointed by 'p'.
+*/
+#define linkgclist(o,p)	((o)->gclist = (p), (p) = obj2gco(o))
+
+
+/*
+** Link a generic collectable object 'o' into list pointed by 'p'.
+*/
+#define linkobjgclist(o,p) (*getgclist(o) = (p), (p) = obj2gco(o))
+
+
+
+/*
+** Clear keys for empty entries in tables. If entry is empty
+** and its key is not marked, mark its entry as dead. This allows the
+** collection of the key, but keeps its entry in the table (its removal
+** could break a chain). The main feature of a dead key is that it must
+** be different from any other value, to do not disturb searches.
+** Other places never manipulate dead keys, because its associated empty
+** value is enough to signal that the entry is logically empty.
+*/
+static void clearkey (Node *n) {
+  lua_assert(isempty(gval(n)));
+  if (keyiswhite(n))
+    setdeadkey(n);  /* unused and unmarked key; remove it */
+}
+
+
+/*
+** tells whether a key or value can be cleared from a weak
+** table. Non-collectable objects are never removed from weak
+** tables. Strings behave as 'values', so are never removed too. for
+** other objects: if really collected, cannot keep them; for objects
+** being finalized, keep them in keys, but not in values
+*/
+static int iscleared (global_State *g, const GCObject *o) {
+  if (o == NULL) return 0;  /* non-collectable value */
+  else if (novariant(o->tt) == LUA_TSTRING) {
+    markobject(g, o);  /* strings are 'values', so are never weak */
+    return 0;
+  }
+  else return iswhite(o);
+}
+
+
+/*
+** barrier that moves collector forward, that is, mark the white object
+** 'v' being pointed by the black object 'o'. (If in sweep phase, clear
+** the black object to white [sweep it] to avoid other barrier calls for
+** this same object.) In the generational mode, 'v' must also become
+** old, if 'o' is old; however, it cannot be changed directly to OLD,
+** because it may still point to non-old objects. So, it is marked as
+** OLD0. In the next cycle it will become OLD1, and in the next it
+** will finally become OLD (regular old).
+*/
+void luaC_barrier_ (lua_State *L, GCObject *o, GCObject *v) {
+  global_State *g = G(L);
+  lua_assert(isblack(o) && iswhite(v) && !isdead(g, v) && !isdead(g, o));
+  if (keepinvariant(g)) {  /* must keep invariant? */
+    reallymarkobject(g, v);  /* restore invariant */
+    if (isold(o)) {
+      lua_assert(!isold(v));  /* white object could not be old */
+      setage(v, G_OLD0);  /* restore generational invariant */
+    }
+  }
+  else {  /* sweep phase */
+    lua_assert(issweepphase(g));
+    makewhite(g, o);  /* mark main obj. as white to avoid other barriers */
+  }
+}
+
+
+/*
+** barrier that moves collector backward, that is, mark the black object
+** pointing to a white object as gray again.
+*/
+void luaC_barrierback_ (lua_State *L, GCObject *o) {
+  global_State *g = G(L);
+  lua_assert(isblack(o) && !isdead(g, o));
+  lua_assert(g->gckind != KGC_GEN || (isold(o) && getage(o) != G_TOUCHED1));
+  if (getage(o) != G_TOUCHED2)  /* not already in gray list? */
+    linkobjgclist(o, g->grayagain);  /* link it in 'grayagain' */
+  black2gray(o);  /* make object gray (again) */
+  setage(o, G_TOUCHED1);  /* touched in current cycle */
+}
+
+
+void luaC_fix (lua_State *L, GCObject *o) {
+  global_State *g = G(L);
+  lua_assert(g->allgc == o);  /* object must be 1st in 'allgc' list! */
+  white2gray(o);  /* they will be gray forever */
+  setage(o, G_OLD);  /* and old forever */
+  g->allgc = o->next;  /* remove object from 'allgc' list */
+  o->next = g->fixedgc;  /* link it to 'fixedgc' list */
+  g->fixedgc = o;
+}
+
+
+/*
+** create a new collectable object (with given type and size) and link
+** it to 'allgc' list.
+*/
+GCObject *luaC_newobj (lua_State *L, int tt, size_t sz) {
+  global_State *g = G(L);
+  GCObject *o = cast(GCObject *, luaM_newobject(L, novariant(tt), sz));
+  o->marked = luaC_white(g);
+  o->tt = tt;
+  o->next = g->allgc;
+  g->allgc = o;
+  return o;
+}
+
+/* }====================================================== */
+
+
+
+/*
+** {======================================================
+** Mark functions
+** =======================================================
+*/
+
+
+/*
+** Mark an object. Userdata, strings, and closed upvalues are visited
+** and turned black here. Other objects are marked gray and added
+** to appropriate list to be visited (and turned black) later. (Open
+** upvalues are already linked in 'headuv' list. They are kept gray
+** to avoid barriers, as their values will be revisited by the thread.)
+*/
+static void reallymarkobject (global_State *g, GCObject *o) {
+  white2gray(o);
+  switch (o->tt) {
+    case LUA_VSHRSTR:
+    case LUA_VLNGSTR: {
+      gray2black(o);
+      break;
+    }
+    case LUA_VUPVAL: {
+      UpVal *uv = gco2upv(o);
+      if (!upisopen(uv))  /* open upvalues are kept gray */
+        gray2black(o);
+      markvalue(g, uv->v);  /* mark its content */
+      break;
+    }
+    case LUA_VUSERDATA: {
+      Udata *u = gco2u(o);
+      if (u->nuvalue == 0) {  /* no user values? */
+        markobjectN(g, u->metatable);  /* mark its metatable */
+        gray2black(o);  /* nothing else to mark */
+        break;
+      }
+      /* else... */
+    }  /* FALLTHROUGH */
+    case LUA_VLCL: case LUA_VCCL: case LUA_VTABLE:
+    case LUA_VTHREAD: case LUA_VPROTO: {
+      linkobjgclist(o, g->gray);
+      break;
+    }
+    default: lua_assert(0); break;
+  }
+}
+
+
+/*
+** mark metamethods for basic types
+*/
+static void markmt (global_State *g) {
+  int i;
+  for (i=0; i < LUA_NUMTAGS; i++)
+    markobjectN(g, g->mt[i]);
+}
+
+
+/*
+** mark all objects in list of being-finalized
+*/
+static lu_mem markbeingfnz (global_State *g) {
+  GCObject *o;
+  lu_mem count = 0;
+  for (o = g->tobefnz; o != NULL; o = o->next) {
+    count++;
+    markobject(g, o);
+  }
+  return count;
+}
+
+
+/*
+** Mark all values stored in marked open upvalues from non-marked threads.
+** (Values from marked threads were already marked when traversing the
+** thread.) Remove from the list threads that no longer have upvalues and
+** not-marked threads.
+*/
+static int remarkupvals (global_State *g) {
+  lua_State *thread;
+  lua_State **p = &g->twups;
+  int work = 0;
+  while ((thread = *p) != NULL) {
+    work++;
+    lua_assert(!isblack(thread));  /* threads are never black */
+    if (isgray(thread) && thread->openupval != NULL)
+      p = &thread->twups;  /* keep marked thread with upvalues in the list */
+    else {  /* thread is not marked or without upvalues */
+      UpVal *uv;
+      *p = thread->twups;  /* remove thread from the list */
+      thread->twups = thread;  /* mark that it is out of list */
+      for (uv = thread->openupval; uv != NULL; uv = uv->u.open.next) {
+        work++;
+        if (!iswhite(uv))  /* upvalue already visited? */
+          markvalue(g, uv->v);  /* mark its value */
+      }
+    }
+  }
+  return work;
+}
+
+
+/*
+** mark root set and reset all gray lists, to start a new collection
+*/
+static void restartcollection (global_State *g) {
+  g->gray = g->grayagain = NULL;
+  g->weak = g->allweak = g->ephemeron = NULL;
+  markobject(g, g->mainthread);
+  markvalue(g, &g->l_registry);
+  markmt(g);
+  markbeingfnz(g);  /* mark any finalizing object left from previous cycle */
+}
+
+/* }====================================================== */
+
+
+/*
+** {======================================================
+** Traverse functions
+** =======================================================
+*/
+
+/*
+** Traverse a table with weak values and link it to proper list. During
+** propagate phase, keep it in 'grayagain' list, to be revisited in the
+** atomic phase. In the atomic phase, if table has any white value,
+** put it in 'weak' list, to be cleared.
+*/
+static void traverseweakvalue (global_State *g, Table *h) {
+  Node *n, *limit = gnodelast(h);
+  /* if there is array part, assume it may have white values (it is not
+     worth traversing it now just to check) */
+  int hasclears = (h->alimit > 0);
+  for (n = gnode(h, 0); n < limit; n++) {  /* traverse hash part */
+    if (isempty(gval(n)))  /* entry is empty? */
+      clearkey(n);  /* clear its key */
+    else {
+      lua_assert(!keyisnil(n));
+      markkey(g, n);
+      if (!hasclears && iscleared(g, gcvalueN(gval(n))))  /* a white value? */
+        hasclears = 1;  /* table will have to be cleared */
+    }
+  }
+  if (g->gcstate == GCSatomic && hasclears)
+    linkgclist(h, g->weak);  /* has to be cleared later */
+  else
+    linkgclist(h, g->grayagain);  /* must retraverse it in atomic phase */
+}
+
+
+/*
+** Traverse an ephemeron table and link it to proper list. Returns true
+** iff any object was marked during this traversal (which implies that
+** convergence has to continue). During propagation phase, keep table
+** in 'grayagain' list, to be visited again in the atomic phase. In
+** the atomic phase, if table has any white->white entry, it has to
+** be revisited during ephemeron convergence (as that key may turn
+** black). Otherwise, if it has any white key, table has to be cleared
+** (in the atomic phase). In generational mode, it (like all visited
+** tables) must be kept in some gray list for post-processing.
+*/
+static int traverseephemeron (global_State *g, Table *h, int inv) {
+  int marked = 0;  /* true if an object is marked in this traversal */
+  int hasclears = 0;  /* true if table has white keys */
+  int hasww = 0;  /* true if table has entry "white-key -> white-value" */
+  unsigned int i;
+  unsigned int asize = luaH_realasize(h);
+  unsigned int nsize = sizenode(h);
+  /* traverse array part */
+  for (i = 0; i < asize; i++) {
+    if (valiswhite(&h->array[i])) {
+      marked = 1;
+      reallymarkobject(g, gcvalue(&h->array[i]));
+    }
+  }
+  /* traverse hash part; if 'inv', traverse descending
+     (see 'convergeephemerons') */
+  for (i = 0; i < nsize; i++) {
+    Node *n = inv ? gnode(h, nsize - 1 - i) : gnode(h, i);
+    if (isempty(gval(n)))  /* entry is empty? */
+      clearkey(n);  /* clear its key */
+    else if (iscleared(g, gckeyN(n))) {  /* key is not marked (yet)? */
+      hasclears = 1;  /* table must be cleared */
+      if (valiswhite(gval(n)))  /* value not marked yet? */
+        hasww = 1;  /* white-white entry */
+    }
+    else if (valiswhite(gval(n))) {  /* value not marked yet? */
+      marked = 1;
+      reallymarkobject(g, gcvalue(gval(n)));  /* mark it now */
+    }
+  }
+  /* link table into proper list */
+  if (g->gcstate == GCSpropagate)
+    linkgclist(h, g->grayagain);  /* must retraverse it in atomic phase */
+  else if (hasww)  /* table has white->white entries? */
+    linkgclist(h, g->ephemeron);  /* have to propagate again */
+  else if (hasclears)  /* table has white keys? */
+    linkgclist(h, g->allweak);  /* may have to clean white keys */
+  else if (g->gckind == KGC_GEN)
+    linkgclist(h, g->grayagain);  /* keep it in some list */
+  else
+    gray2black(h);
+  return marked;
+}
+
+
+static void traversestrongtable (global_State *g, Table *h) {
+  Node *n, *limit = gnodelast(h);
+  unsigned int i;
+  unsigned int asize = luaH_realasize(h);
+  for (i = 0; i < asize; i++)  /* traverse array part */
+    markvalue(g, &h->array[i]);
+  for (n = gnode(h, 0); n < limit; n++) {  /* traverse hash part */
+    if (isempty(gval(n)))  /* entry is empty? */
+      clearkey(n);  /* clear its key */
+    else {
+      lua_assert(!keyisnil(n));
+      markkey(g, n);
+      markvalue(g, gval(n));
+    }
+  }
+  if (g->gckind == KGC_GEN) {
+    linkgclist(h, g->grayagain);  /* keep it in some gray list */
+    black2gray(h);
+  }
+}
+
+
+static lu_mem traversetable (global_State *g, Table *h) {
+  const char *weakkey, *weakvalue;
+  const TValue *mode = gfasttm(g, h->metatable, TM_MODE);
+  markobjectN(g, h->metatable);
+  if (mode && ttisstring(mode) &&  /* is there a weak mode? */
+      (cast_void(weakkey = strchr(svalue(mode), 'k')),
+       cast_void(weakvalue = strchr(svalue(mode), 'v')),
+       (weakkey || weakvalue))) {  /* is really weak? */
+    black2gray(h);  /* keep table gray */
+    if (!weakkey)  /* strong keys? */
+      traverseweakvalue(g, h);
+    else if (!weakvalue)  /* strong values? */
+      traverseephemeron(g, h, 0);
+    else  /* all weak */
+      linkgclist(h, g->allweak);  /* nothing to traverse now */
+  }
+  else  /* not weak */
+    traversestrongtable(g, h);
+  return 1 + h->alimit + 2 * allocsizenode(h);
+}
+
+
+static int traverseudata (global_State *g, Udata *u) {
+  int i;
+  markobjectN(g, u->metatable);  /* mark its metatable */
+  for (i = 0; i < u->nuvalue; i++)
+    markvalue(g, &u->uv[i].uv);
+  if (g->gckind == KGC_GEN) {
+    linkgclist(u, g->grayagain);  /* keep it in some gray list */
+    black2gray(u);
+  }
+  return 1 + u->nuvalue;
+}
+
+
+/*
+** Traverse a prototype. (While a prototype is being build, its
+** arrays can be larger than needed; the extra slots are filled with
+** NULL, so the use of 'markobjectN')
+*/
+static int traverseproto (global_State *g, Proto *f) {
+  int i;
+  markobjectN(g, f->source);
+  for (i = 0; i < f->sizek; i++)  /* mark literals */
+    markvalue(g, &f->k[i]);
+  for (i = 0; i < f->sizeupvalues; i++)  /* mark upvalue names */
+    markobjectN(g, f->upvalues[i].name);
+  for (i = 0; i < f->sizep; i++)  /* mark nested protos */
+    markobjectN(g, f->p[i]);
+  for (i = 0; i < f->sizelocvars; i++)  /* mark local-variable names */
+    markobjectN(g, f->locvars[i].varname);
+  return 1 + f->sizek + f->sizeupvalues + f->sizep + f->sizelocvars;
+}
+
+
+static int traverseCclosure (global_State *g, CClosure *cl) {
+  int i;
+  for (i = 0; i < cl->nupvalues; i++)  /* mark its upvalues */
+    markvalue(g, &cl->upvalue[i]);
+  return 1 + cl->nupvalues;
+}
+
+/*
+** Traverse a Lua closure, marking its prototype and its upvalues.
+** (Both can be NULL while closure is being created.)
+*/
+static int traverseLclosure (global_State *g, LClosure *cl) {
+  int i;
+  markobjectN(g, cl->p);  /* mark its prototype */
+  for (i = 0; i < cl->nupvalues; i++) {  /* visit its upvalues */
+    UpVal *uv = cl->upvals[i];
+    markobjectN(g, uv);  /* mark upvalue */
+  }
+  return 1 + cl->nupvalues;
+}
+
+
+/*
+** Traverse a thread, marking the elements in the stack up to its top
+** and cleaning the rest of the stack in the final traversal.
+** That ensures that the entire stack have valid (non-dead) objects.
+*/
+static int traversethread (global_State *g, lua_State *th) {
+  UpVal *uv;
+  StkId o = th->stack;
+  if (o == NULL)
+    return 1;  /* stack not completely built yet */
+  lua_assert(g->gcstate == GCSatomic ||
+             th->openupval == NULL || isintwups(th));
+  for (; o < th->top; o++)  /* mark live elements in the stack */
+    markvalue(g, s2v(o));
+  for (uv = th->openupval; uv != NULL; uv = uv->u.open.next)
+    markobject(g, uv);  /* open upvalues cannot be collected */
+  if (g->gcstate == GCSatomic) {  /* final traversal? */
+    StkId lim = th->stack + th->stacksize;  /* real end of stack */
+    for (; o < lim; o++)  /* clear not-marked stack slice */
+      setnilvalue(s2v(o));
+    /* 'remarkupvals' may have removed thread from 'twups' list */
+    if (!isintwups(th) && th->openupval != NULL) {
+      th->twups = g->twups;  /* link it back to the list */
+      g->twups = th;
+    }
+  }
+  else if (!g->gcemergency)
+    luaD_shrinkstack(th); /* do not change stack in emergency cycle */
+  return 1 + th->stacksize;
+}
+
+
+/*
+** traverse one gray object, turning it to black (except for threads,
+** which are always gray).
+*/
+static lu_mem propagatemark (global_State *g) {
+  GCObject *o = g->gray;
+  gray2black(o);
+  g->gray = *getgclist(o);  /* remove from 'gray' list */
+  switch (o->tt) {
+    case LUA_VTABLE: return traversetable(g, gco2t(o));
+    case LUA_VUSERDATA: return traverseudata(g, gco2u(o));
+    case LUA_VLCL: return traverseLclosure(g, gco2lcl(o));
+    case LUA_VCCL: return traverseCclosure(g, gco2ccl(o));
+    case LUA_VPROTO: return traverseproto(g, gco2p(o));
+    case LUA_VTHREAD: {
+      lua_State *th = gco2th(o);
+      linkgclist(th, g->grayagain);  /* insert into 'grayagain' list */
+      black2gray(o);
+      return traversethread(g, th);
+    }
+    default: lua_assert(0); return 0;
+  }
+}
+
+
+static lu_mem propagateall (global_State *g) {
+  lu_mem tot = 0;
+  while (g->gray)
+    tot += propagatemark(g);
+  return tot;
+}
+
+
+/*
+** Traverse all ephemeron tables propagating marks from keys to values.
+** Repeat until it converges, that is, nothing new is marked. 'dir'
+** inverts the direction of the traversals, trying to speed up
+** convergence on chains in the same table.
+**
+*/
+static void convergeephemerons (global_State *g) {
+  int changed;
+  int dir = 0;
+  do {
+    GCObject *w;
+    GCObject *next = g->ephemeron;  /* get ephemeron list */
+    g->ephemeron = NULL;  /* tables may return to this list when traversed */
+    changed = 0;
+    while ((w = next) != NULL) {  /* for each ephemeron table */
+      next = gco2t(w)->gclist;  /* list is rebuilt during loop */
+      if (traverseephemeron(g, gco2t(w), dir)) {  /* marked some value? */
+        propagateall(g);  /* propagate changes */
+        changed = 1;  /* will have to revisit all ephemeron tables */
+      }
+    }
+    dir = !dir;  /* invert direction next time */
+  } while (changed);  /* repeat until no more changes */
+}
+
+/* }====================================================== */
+
+
+/*
+** {======================================================
+** Sweep Functions
+** =======================================================
+*/
+
+
+/*
+** clear entries with unmarked keys from all weaktables in list 'l'
+*/
+static void clearbykeys (global_State *g, GCObject *l) {
+  for (; l; l = gco2t(l)->gclist) {
+    Table *h = gco2t(l);
+    Node *limit = gnodelast(h);
+    Node *n;
+    for (n = gnode(h, 0); n < limit; n++) {
+      if (iscleared(g, gckeyN(n)))  /* unmarked key? */
+        setempty(gval(n));  /* remove entry */
+      if (isempty(gval(n)))  /* is entry empty? */
+        clearkey(n);  /* clear its key */
+    }
+  }
+}
+
+
+/*
+** clear entries with unmarked values from all weaktables in list 'l' up
+** to element 'f'
+*/
+static void clearbyvalues (global_State *g, GCObject *l, GCObject *f) {
+  for (; l != f; l = gco2t(l)->gclist) {
+    Table *h = gco2t(l);
+    Node *n, *limit = gnodelast(h);
+    unsigned int i;
+    unsigned int asize = luaH_realasize(h);
+    for (i = 0; i < asize; i++) {
+      TValue *o = &h->array[i];
+      if (iscleared(g, gcvalueN(o)))  /* value was collected? */
+        setempty(o);  /* remove entry */
+    }
+    for (n = gnode(h, 0); n < limit; n++) {
+      if (iscleared(g, gcvalueN(gval(n))))  /* unmarked value? */
+        setempty(gval(n));  /* remove entry */
+      if (isempty(gval(n)))  /* is entry empty? */
+        clearkey(n);  /* clear its key */
+    }
+  }
+}
+
+
+static void freeupval (lua_State *L, UpVal *uv) {
+  if (upisopen(uv))
+    luaF_unlinkupval(uv);
+  luaM_free(L, uv);
+}
+
+
+static void freeobj (lua_State *L, GCObject *o) {
+  switch (o->tt) {
+    case LUA_VPROTO:
+      luaF_freeproto(L, gco2p(o));
+      break;
+    case LUA_VUPVAL:
+      freeupval(L, gco2upv(o));
+      break;
+    case LUA_VLCL:
+      luaM_freemem(L, o, sizeLclosure(gco2lcl(o)->nupvalues));
+      break;
+    case LUA_VCCL:
+      luaM_freemem(L, o, sizeCclosure(gco2ccl(o)->nupvalues));
+      break;
+    case LUA_VTABLE:
+      luaH_free(L, gco2t(o));
+      break;
+    case LUA_VTHREAD:
+      luaE_freethread(L, gco2th(o));
+      break;
+    case LUA_VUSERDATA: {
+      Udata *u = gco2u(o);
+      luaM_freemem(L, o, sizeudata(u->nuvalue, u->len));
+      break;
+    }
+    case LUA_VSHRSTR:
+      luaS_remove(L, gco2ts(o));  /* remove it from hash table */
+      luaM_freemem(L, o, sizelstring(gco2ts(o)->shrlen));
+      break;
+    case LUA_VLNGSTR:
+      luaM_freemem(L, o, sizelstring(gco2ts(o)->u.lnglen));
+      break;
+    default: lua_assert(0);
+  }
+}
+
+
+/*
+** sweep at most 'countin' elements from a list of GCObjects erasing dead
+** objects, where a dead object is one marked with the old (non current)
+** white; change all non-dead objects back to white, preparing for next
+** collection cycle. Return where to continue the traversal or NULL if
+** list is finished. ('*countout' gets the number of elements traversed.)
+*/
+static GCObject **sweeplist (lua_State *L, GCObject **p, int countin,
+                             int *countout) {
+  global_State *g = G(L);
+  int ow = otherwhite(g);
+  int i;
+  int white = luaC_white(g);  /* current white */
+  for (i = 0; *p != NULL && i < countin; i++) {
+    GCObject *curr = *p;
+    int marked = curr->marked;
+    if (isdeadm(ow, marked)) {  /* is 'curr' dead? */
+      *p = curr->next;  /* remove 'curr' from list */
+      freeobj(L, curr);  /* erase 'curr' */
+    }
+    else {  /* change mark to 'white' */
+      curr->marked = cast_byte((marked & maskcolors) | white);
+      p = &curr->next;  /* go to next element */
+    }
+  }
+  if (countout)
+    *countout = i;  /* number of elements traversed */
+  return (*p == NULL) ? NULL : p;
+}
+
+
+/*
+** sweep a list until a live object (or end of list)
+*/
+static GCObject **sweeptolive (lua_State *L, GCObject **p) {
+  GCObject **old = p;
+  do {
+    p = sweeplist(L, p, 1, NULL);
+  } while (p == old);
+  return p;
+}
+
+/* }====================================================== */
+
+
+/*
+** {======================================================
+** Finalization
+** =======================================================
+*/
+
+/*
+** If possible, shrink string table.
+*/
+static void checkSizes (lua_State *L, global_State *g) {
+  if (!g->gcemergency) {
+    if (g->strt.nuse < g->strt.size / 4) {  /* string table too big? */
+      l_mem olddebt = g->GCdebt;
+      luaS_resize(L, g->strt.size / 2);
+      g->GCestimate += g->GCdebt - olddebt;  /* correct estimate */
+    }
+  }
+}
+
+
+/*
+** Get the next udata to be finalized from the 'tobefnz' list, and
+** link it back into the 'allgc' list.
+*/
+static GCObject *udata2finalize (global_State *g) {
+  GCObject *o = g->tobefnz;  /* get first element */
+  lua_assert(tofinalize(o));
+  g->tobefnz = o->next;  /* remove it from 'tobefnz' list */
+  o->next = g->allgc;  /* return it to 'allgc' list */
+  g->allgc = o;
+  resetbit(o->marked, FINALIZEDBIT);  /* object is "normal" again */
+  if (issweepphase(g))
+    makewhite(g, o);  /* "sweep" object */
+  return o;
+}
+
+
+static void dothecall (lua_State *L, void *ud) {
+  UNUSED(ud);
+  luaD_callnoyield(L, L->top - 2, 0);
+}
+
+
+static void GCTM (lua_State *L) {
+  global_State *g = G(L);
+  const TValue *tm;
+  TValue v;
+  lua_assert(!g->gcemergency);
+  setgcovalue(L, &v, udata2finalize(g));
+  tm = luaT_gettmbyobj(L, &v, TM_GC);
+  if (!notm(tm)) {  /* is there a finalizer? */
+    int status;
+    lu_byte oldah = L->allowhook;
+    int running  = g->gcrunning;
+    L->allowhook = 0;  /* stop debug hooks during GC metamethod */
+    g->gcrunning = 0;  /* avoid GC steps */
+    setobj2s(L, L->top++, tm);  /* push finalizer... */
+    setobj2s(L, L->top++, &v);  /* ... and its argument */
+    L->ci->callstatus |= CIST_FIN;  /* will run a finalizer */
+    status = luaD_pcall(L, dothecall, NULL, savestack(L, L->top - 2), 0);
+    L->ci->callstatus &= ~CIST_FIN;  /* not running a finalizer anymore */
+    L->allowhook = oldah;  /* restore hooks */
+    g->gcrunning = running;  /* restore state */
+    if (unlikely(status != LUA_OK)) {  /* error while running __gc? */
+      luaE_warnerror(L, "__gc metamethod");
+      L->top--;  /* pops error object */
+    }
+  }
+}
+
+
+/*
+** Call a few finalizers
+*/
+static int runafewfinalizers (lua_State *L, int n) {
+  global_State *g = G(L);
+  int i;
+  for (i = 0; i < n && g->tobefnz; i++)
+    GCTM(L);  /* call one finalizer */
+  return i;
+}
+
+
+/*
+** call all pending finalizers
+*/
+static void callallpendingfinalizers (lua_State *L) {
+  global_State *g = G(L);
+  while (g->tobefnz)
+    GCTM(L);
+}
+
+
+/*
+** find last 'next' field in list 'p' list (to add elements in its end)
+*/
+static GCObject **findlast (GCObject **p) {
+  while (*p != NULL)
+    p = &(*p)->next;
+  return p;
+}
+
+
+/*
+** Move all unreachable objects (or 'all' objects) that need
+** finalization from list 'finobj' to list 'tobefnz' (to be finalized).
+** (Note that objects after 'finobjold' cannot be white, so they
+** don't need to be traversed. In incremental mode, 'finobjold' is NULL,
+** so the whole list is traversed.)
+*/
+static void separatetobefnz (global_State *g, int all) {
+  GCObject *curr;
+  GCObject **p = &g->finobj;
+  GCObject **lastnext = findlast(&g->tobefnz);
+  while ((curr = *p) != g->finobjold) {  /* traverse all finalizable objects */
+    lua_assert(tofinalize(curr));
+    if (!(iswhite(curr) || all))  /* not being collected? */
+      p = &curr->next;  /* don't bother with it */
+    else {
+      if (curr == g->finobjsur)  /* removing 'finobjsur'? */
+        g->finobjsur = curr->next;  /* correct it */
+      *p = curr->next;  /* remove 'curr' from 'finobj' list */
+      curr->next = *lastnext;  /* link at the end of 'tobefnz' list */
+      *lastnext = curr;
+      lastnext = &curr->next;
+    }
+  }
+}
+
+
+/*
+** if object 'o' has a finalizer, remove it from 'allgc' list (must
+** search the list to find it) and link it in 'finobj' list.
+*/
+void luaC_checkfinalizer (lua_State *L, GCObject *o, Table *mt) {
+  global_State *g = G(L);
+  if (tofinalize(o) ||                 /* obj. is already marked... */
+      gfasttm(g, mt, TM_GC) == NULL)   /* or has no finalizer? */
+    return;  /* nothing to be done */
+  else {  /* move 'o' to 'finobj' list */
+    GCObject **p;
+    if (issweepphase(g)) {
+      makewhite(g, o);  /* "sweep" object 'o' */
+      if (g->sweepgc == &o->next)  /* should not remove 'sweepgc' object */
+        g->sweepgc = sweeptolive(L, g->sweepgc);  /* change 'sweepgc' */
+    }
+    else {  /* correct pointers into 'allgc' list, if needed */
+      if (o == g->survival)
+        g->survival = o->next;
+      if (o == g->old)
+        g->old = o->next;
+      if (o == g->reallyold)
+        g->reallyold = o->next;
+    }
+    /* search for pointer pointing to 'o' */
+    for (p = &g->allgc; *p != o; p = &(*p)->next) { /* empty */ }
+    *p = o->next;  /* remove 'o' from 'allgc' list */
+    o->next = g->finobj;  /* link it in 'finobj' list */
+    g->finobj = o;
+    l_setbit(o->marked, FINALIZEDBIT);  /* mark it as such */
+  }
+}
+
+/* }====================================================== */
+
+
+/*
+** {======================================================
+** Generational Collector
+** =======================================================
+*/
+
+static void setpause (global_State *g);
+
+
+/* mask to erase all color bits, not changing gen-related stuff */
+#define maskgencolors	(~(bitmask(BLACKBIT) | WHITEBITS))
+
+
+/*
+** Sweep a list of objects, deleting dead ones and turning
+** the non dead to old (without changing their colors).
+*/
+static void sweep2old (lua_State *L, GCObject **p) {
+  GCObject *curr;
+  while ((curr = *p) != NULL) {
+    if (iswhite(curr)) {  /* is 'curr' dead? */
+      lua_assert(isdead(G(L), curr));
+      *p = curr->next;  /* remove 'curr' from list */
+      freeobj(L, curr);  /* erase 'curr' */
+    }
+    else {  /* all surviving objects become old */
+      setage(curr, G_OLD);
+      p = &curr->next;  /* go to next element */
+    }
+  }
+}
+
+
+/*
+** Sweep for generational mode. Delete dead objects. (Because the
+** collection is not incremental, there are no "new white" objects
+** during the sweep. So, any white object must be dead.) For
+** non-dead objects, advance their ages and clear the color of
+** new objects. (Old objects keep their colors.)
+*/
+static GCObject **sweepgen (lua_State *L, global_State *g, GCObject **p,
+                            GCObject *limit) {
+  static const lu_byte nextage[] = {
+    G_SURVIVAL,  /* from G_NEW */
+    G_OLD1,      /* from G_SURVIVAL */
+    G_OLD1,      /* from G_OLD0 */
+    G_OLD,       /* from G_OLD1 */
+    G_OLD,       /* from G_OLD (do not change) */
+    G_TOUCHED1,  /* from G_TOUCHED1 (do not change) */
+    G_TOUCHED2   /* from G_TOUCHED2 (do not change) */
+  };
+  int white = luaC_white(g);
+  GCObject *curr;
+  while ((curr = *p) != limit) {
+    if (iswhite(curr)) {  /* is 'curr' dead? */
+      lua_assert(!isold(curr) && isdead(g, curr));
+      *p = curr->next;  /* remove 'curr' from list */
+      freeobj(L, curr);  /* erase 'curr' */
+    }
+    else {  /* correct mark and age */
+      if (getage(curr) == G_NEW)
+        curr->marked = cast_byte((curr->marked & maskgencolors) | white);
+      setage(curr, nextage[getage(curr)]);
+      p = &curr->next;  /* go to next element */
+    }
+  }
+  return p;
+}
+
+
+/*
+** Traverse a list making all its elements white and clearing their
+** age.
+*/
+static void whitelist (global_State *g, GCObject *p) {
+  int white = luaC_white(g);
+  for (; p != NULL; p = p->next)
+    p->marked = cast_byte((p->marked & maskcolors) | white);
+}
+
+
+/*
+** Correct a list of gray objects.
+** Because this correction is done after sweeping, young objects might
+** be turned white and still be in the list. They are only removed.
+** For tables and userdata, advance 'touched1' to 'touched2'; 'touched2'
+** objects become regular old and are removed from the list.
+** For threads, just remove white ones from the list.
+*/
+static GCObject **correctgraylist (GCObject **p) {
+  GCObject *curr;
+  while ((curr = *p) != NULL) {
+    switch (curr->tt) {
+      case LUA_VTABLE: case LUA_VUSERDATA: {
+        GCObject **next = getgclist(curr);
+        if (getage(curr) == G_TOUCHED1) {  /* touched in this cycle? */
+          lua_assert(isgray(curr));
+          gray2black(curr);  /* make it black, for next barrier */
+          changeage(curr, G_TOUCHED1, G_TOUCHED2);
+          p = next;  /* go to next element */
+        }
+        else {  /* not touched in this cycle */
+          if (!iswhite(curr)) {  /* not white? */
+            lua_assert(isold(curr));
+            if (getage(curr) == G_TOUCHED2)  /* advance from G_TOUCHED2... */
+              changeage(curr, G_TOUCHED2, G_OLD);  /* ... to G_OLD */
+            gray2black(curr);  /* make it black */
+          }
+          /* else, object is white: just remove it from this list */
+          *p = *next;  /* remove 'curr' from gray list */
+        }
+        break;
+      }
+      case LUA_VTHREAD: {
+        lua_State *th = gco2th(curr);
+        lua_assert(!isblack(th));
+        if (iswhite(th))  /* new object? */
+          *p = th->gclist;  /* remove from gray list */
+        else  /* old threads remain gray */
+          p = &th->gclist;  /* go to next element */
+        break;
+      }
+      default: lua_assert(0);  /* nothing more could be gray here */
+    }
+  }
+  return p;
+}
+
+
+/*
+** Correct all gray lists, coalescing them into 'grayagain'.
+*/
+static void correctgraylists (global_State *g) {
+  GCObject **list = correctgraylist(&g->grayagain);
+  *list = g->weak; g->weak = NULL;
+  list = correctgraylist(list);
+  *list = g->allweak; g->allweak = NULL;
+  list = correctgraylist(list);
+  *list = g->ephemeron; g->ephemeron = NULL;
+  correctgraylist(list);
+}
+
+
+/*
+** Mark 'OLD1' objects when starting a new young collection.
+** Gray objects are already in some gray list, and so will be visited
+** in the atomic step.
+*/
+static void markold (global_State *g, GCObject *from, GCObject *to) {
+  GCObject *p;
+  for (p = from; p != to; p = p->next) {
+    if (getage(p) == G_OLD1) {
+      lua_assert(!iswhite(p));
+      if (isblack(p)) {
+        black2gray(p);  /* should be '2white', but gray works too */
+        reallymarkobject(g, p);
+      }
+    }
+  }
+}
+
+
+/*
+** Finish a young-generation collection.
+*/
+static void finishgencycle (lua_State *L, global_State *g) {
+  correctgraylists(g);
+  checkSizes(L, g);
+  g->gcstate = GCSpropagate;  /* skip restart */
+  if (!g->gcemergency)
+    callallpendingfinalizers(L);
+}
+
+
+/*
+** Does a young collection. First, mark 'OLD1' objects.  (Only survival
+** and "recent old" lists can contain 'OLD1' objects. New lists cannot
+** contain 'OLD1' objects, at most 'OLD0' objects that were already
+** visited when marked old.) Then does the atomic step. Then,
+** sweep all lists and advance pointers. Finally, finish the collection.
+*/
+static void youngcollection (lua_State *L, global_State *g) {
+  GCObject **psurvival;  /* to point to first non-dead survival object */
+  lua_assert(g->gcstate == GCSpropagate);
+  markold(g, g->survival, g->reallyold);
+  markold(g, g->finobj, g->finobjrold);
+  atomic(L);
+
+  /* sweep nursery and get a pointer to its last live element */
+  psurvival = sweepgen(L, g, &g->allgc, g->survival);
+  /* sweep 'survival' and 'old' */
+  sweepgen(L, g, psurvival, g->reallyold);
+  g->reallyold = g->old;
+  g->old = *psurvival;  /* 'survival' survivals are old now */
+  g->survival = g->allgc;  /* all news are survivals */
+
+  /* repeat for 'finobj' lists */
+  psurvival = sweepgen(L, g, &g->finobj, g->finobjsur);
+  /* sweep 'survival' and 'old' */
+  sweepgen(L, g, psurvival, g->finobjrold);
+  g->finobjrold = g->finobjold;
+  g->finobjold = *psurvival;  /* 'survival' survivals are old now */
+  g->finobjsur = g->finobj;  /* all news are survivals */
+
+  sweepgen(L, g, &g->tobefnz, NULL);
+
+  finishgencycle(L, g);
+}
+
+
+static void atomic2gen (lua_State *L, global_State *g) {
+  /* sweep all elements making them old */
+  sweep2old(L, &g->allgc);
+  /* everything alive now is old */
+  g->reallyold = g->old = g->survival = g->allgc;
+
+  /* repeat for 'finobj' lists */
+  sweep2old(L, &g->finobj);
+  g->finobjrold = g->finobjold = g->finobjsur = g->finobj;
+
+  sweep2old(L, &g->tobefnz);
+
+  g->gckind = KGC_GEN;
+  g->lastatomic = 0;
+  g->GCestimate = gettotalbytes(g);  /* base for memory control */
+  finishgencycle(L, g);
+}
+
+
+/*
+** Enter generational mode. Must go until the end of an atomic cycle
+** to ensure that all threads and weak tables are in the gray lists.
+** Then, turn all objects into old and finishes the collection.
+*/
+static lu_mem entergen (lua_State *L, global_State *g) {
+  lu_mem numobjs;
+  luaC_runtilstate(L, bitmask(GCSpause));  /* prepare to start a new cycle */
+  luaC_runtilstate(L, bitmask(GCSpropagate));  /* start new cycle */
+  numobjs = atomic(L);  /* propagates all and then do the atomic stuff */
+  atomic2gen(L, g);
+  return numobjs;
+}
+
+
+/*
+** Enter incremental mode. Turn all objects white, make all
+** intermediate lists point to NULL (to avoid invalid pointers),
+** and go to the pause state.
+*/
+static void enterinc (global_State *g) {
+  whitelist(g, g->allgc);
+  g->reallyold = g->old = g->survival = NULL;
+  whitelist(g, g->finobj);
+  whitelist(g, g->tobefnz);
+  g->finobjrold = g->finobjold = g->finobjsur = NULL;
+  g->gcstate = GCSpause;
+  g->gckind = KGC_INC;
+  g->lastatomic = 0;
+}
+
+
+/*
+** Change collector mode to 'newmode'.
+*/
+void luaC_changemode (lua_State *L, int newmode) {
+  global_State *g = G(L);
+  if (newmode != g->gckind) {
+    if (newmode == KGC_GEN)  /* entering generational mode? */
+      entergen(L, g);
+    else
+      enterinc(g);  /* entering incremental mode */
+  }
+  g->lastatomic = 0;
+}
+
+
+/*
+** Does a full collection in generational mode.
+*/
+static lu_mem fullgen (lua_State *L, global_State *g) {
+  enterinc(g);
+  return entergen(L, g);
+}
+
+
+/*
+** Set debt for the next minor collection, which will happen when
+** memory grows 'genminormul'%.
+*/
+static void setminordebt (global_State *g) {
+  luaE_setdebt(g, -(cast(l_mem, (gettotalbytes(g) / 100)) * g->genminormul));
+}
+
+
+/*
+** Does a major collection after last collection was a "bad collection".
+**
+** When the program is building a big structure, it allocates lots of
+** memory but generates very little garbage. In those scenarios,
+** the generational mode just wastes time doing small collections, and
+** major collections are frequently what we call a "bad collection", a
+** collection that frees too few objects. To avoid the cost of switching
+** between generational mode and the incremental mode needed for full
+** (major) collections, the collector tries to stay in incremental mode
+** after a bad collection, and to switch back to generational mode only
+** after a "good" collection (one that traverses less than 9/8 objects
+** of the previous one).
+** The collector must choose whether to stay in incremental mode or to
+** switch back to generational mode before sweeping. At this point, it
+** does not know the real memory in use, so it cannot use memory to
+** decide whether to return to generational mode. Instead, it uses the
+** number of objects traversed (returned by 'atomic') as a proxy. The
+** field 'g->lastatomic' keeps this count from the last collection.
+** ('g->lastatomic != 0' also means that the last collection was bad.)
+*/
+static void stepgenfull (lua_State *L, global_State *g) {
+  lu_mem newatomic;  /* count of traversed objects */
+  lu_mem lastatomic = g->lastatomic;  /* count from last collection */
+  if (g->gckind == KGC_GEN)  /* still in generational mode? */
+    enterinc(g);  /* enter incremental mode */
+  luaC_runtilstate(L, bitmask(GCSpropagate));  /* start new cycle */
+  newatomic = atomic(L);  /* mark everybody */
+  if (newatomic < lastatomic + (lastatomic >> 3)) {  /* good collection? */
+    atomic2gen(L, g);  /* return to generational mode */
+    setminordebt(g);
+  }
+  else {  /* another bad collection; stay in incremental mode */
+    g->GCestimate = gettotalbytes(g);  /* first estimate */;
+    entersweep(L);
+    luaC_runtilstate(L, bitmask(GCSpause));  /* finish collection */
+    setpause(g);
+    g->lastatomic = newatomic;
+  }
+}
+
+
+/*
+** Does a generational "step".
+** Usually, this means doing a minor collection and setting the debt to
+** make another collection when memory grows 'genminormul'% larger.
+**
+** However, there are exceptions.  If memory grows 'genmajormul'%
+** larger than it was at the end of the last major collection (kept
+** in 'g->GCestimate'), the function does a major collection. At the
+** end, it checks whether the major collection was able to free a
+** decent amount of memory (at least half the growth in memory since
+** previous major collection). If so, the collector keeps its state,
+** and the next collection will probably be minor again. Otherwise,
+** we have what we call a "bad collection". In that case, set the field
+** 'g->lastatomic' to signal that fact, so that the next collection will
+** go to 'stepgenfull'.
+**
+** 'GCdebt <= 0' means an explicit call to GC step with "size" zero;
+** in that case, do a minor collection.
+*/
+static void genstep (lua_State *L, global_State *g) {
+  if (g->lastatomic != 0)  /* last collection was a bad one? */
+    stepgenfull(L, g);  /* do a full step */
+  else {
+    lu_mem majorbase = g->GCestimate;  /* memory after last major collection */
+    lu_mem majorinc = (majorbase / 100) * getgcparam(g->genmajormul);
+    if (g->GCdebt > 0 && gettotalbytes(g) > majorbase + majorinc) {
+      lu_mem numobjs = fullgen(L, g);  /* do a major collection */
+      if (gettotalbytes(g) < majorbase + (majorinc / 2)) {
+        /* collected at least half of memory growth since last major
+           collection; keep doing minor collections */
+        setminordebt(g);
+      }
+      else {  /* bad collection */
+        g->lastatomic = numobjs;  /* signal that last collection was bad */
+        setpause(g);  /* do a long wait for next (major) collection */
+      }
+    }
+    else {  /* regular case; do a minor collection */
+      youngcollection(L, g);
+      setminordebt(g);
+      g->GCestimate = majorbase;  /* preserve base value */
+    }
+  }
+  lua_assert(isdecGCmodegen(g));
+}
+
+/* }====================================================== */
+
+
+/*
+** {======================================================
+** GC control
+** =======================================================
+*/
+
+
+/*
+** Set the "time" to wait before starting a new GC cycle; cycle will
+** start when memory use hits the threshold of ('estimate' * pause /
+** PAUSEADJ). (Division by 'estimate' should be OK: it cannot be zero,
+** because Lua cannot even start with less than PAUSEADJ bytes).
+*/
+static void setpause (global_State *g) {
+  l_mem threshold, debt;
+  int pause = getgcparam(g->gcpause);
+  l_mem estimate = g->GCestimate / PAUSEADJ;  /* adjust 'estimate' */
+  lua_assert(estimate > 0);
+  threshold = (pause < MAX_LMEM / estimate)  /* overflow? */
+            ? estimate * pause  /* no overflow */
+            : MAX_LMEM;  /* overflow; truncate to maximum */
+  debt = gettotalbytes(g) - threshold;
+  if (debt > 0) debt = 0;
+  luaE_setdebt(g, debt);
+}
+
+
+/*
+** Enter first sweep phase.
+** The call to 'sweeptolive' makes the pointer point to an object
+** inside the list (instead of to the header), so that the real sweep do
+** not need to skip objects created between "now" and the start of the
+** real sweep.
+*/
+static void entersweep (lua_State *L) {
+  global_State *g = G(L);
+  g->gcstate = GCSswpallgc;
+  lua_assert(g->sweepgc == NULL);
+  g->sweepgc = sweeptolive(L, &g->allgc);
+}
+
+
+/*
+** Delete all objects in list 'p' until (but not including) object
+** 'limit'.
+*/
+static void deletelist (lua_State *L, GCObject *p, GCObject *limit) {
+  while (p != limit) {
+    GCObject *next = p->next;
+    freeobj(L, p);
+    p = next;
+  }
+}
+
+
+/*
+** Call all finalizers of the objects in the given Lua state, and
+** then free all objects, except for the main thread.
+*/
+void luaC_freeallobjects (lua_State *L) {
+  global_State *g = G(L);
+  luaC_changemode(L, KGC_INC);
+  separatetobefnz(g, 1);  /* separate all objects with finalizers */
+  lua_assert(g->finobj == NULL);
+  callallpendingfinalizers(L);
+  deletelist(L, g->allgc, obj2gco(g->mainthread));
+  deletelist(L, g->finobj, NULL);
+  deletelist(L, g->fixedgc, NULL);  /* collect fixed objects */
+  lua_assert(g->strt.nuse == 0);
+}
+
+
+static lu_mem atomic (lua_State *L) {
+  global_State *g = G(L);
+  lu_mem work = 0;
+  GCObject *origweak, *origall;
+  GCObject *grayagain = g->grayagain;  /* save original list */
+  g->grayagain = NULL;
+  lua_assert(g->ephemeron == NULL && g->weak == NULL);
+  lua_assert(!iswhite(g->mainthread));
+  g->gcstate = GCSatomic;
+  markobject(g, L);  /* mark running thread */
+  /* registry and global metatables may be changed by API */
+  markvalue(g, &g->l_registry);
+  markmt(g);  /* mark global metatables */
+  work += propagateall(g);  /* empties 'gray' list */
+  /* remark occasional upvalues of (maybe) dead threads */
+  work += remarkupvals(g);
+  work += propagateall(g);  /* propagate changes */
+  g->gray = grayagain;
+  work += propagateall(g);  /* traverse 'grayagain' list */
+  convergeephemerons(g);
+  /* at this point, all strongly accessible objects are marked. */
+  /* Clear values from weak tables, before checking finalizers */
+  clearbyvalues(g, g->weak, NULL);
+  clearbyvalues(g, g->allweak, NULL);
+  origweak = g->weak; origall = g->allweak;
+  separatetobefnz(g, 0);  /* separate objects to be finalized */
+  work += markbeingfnz(g);  /* mark objects that will be finalized */
+  work += propagateall(g);  /* remark, to propagate 'resurrection' */
+  convergeephemerons(g);
+  /* at this point, all resurrected objects are marked. */
+  /* remove dead objects from weak tables */
+  clearbykeys(g, g->ephemeron);  /* clear keys from all ephemeron tables */
+  clearbykeys(g, g->allweak);  /* clear keys from all 'allweak' tables */
+  /* clear values from resurrected weak tables */
+  clearbyvalues(g, g->weak, origweak);
+  clearbyvalues(g, g->allweak, origall);
+  luaS_clearcache(g);
+  g->currentwhite = cast_byte(otherwhite(g));  /* flip current white */
+  lua_assert(g->gray == NULL);
+  return work;  /* estimate of slots marked by 'atomic' */
+}
+
+
+static int sweepstep (lua_State *L, global_State *g,
+                      int nextstate, GCObject **nextlist) {
+  if (g->sweepgc) {
+    l_mem olddebt = g->GCdebt;
+    int count;
+    g->sweepgc = sweeplist(L, g->sweepgc, GCSWEEPMAX, &count);
+    g->GCestimate += g->GCdebt - olddebt;  /* update estimate */
+    return count;
+  }
+  else {  /* enter next state */
+    g->gcstate = nextstate;
+    g->sweepgc = nextlist;
+    return 0;  /* no work done */
+  }
+}
+
+
+static lu_mem singlestep (lua_State *L) {
+  global_State *g = G(L);
+  switch (g->gcstate) {
+    case GCSpause: {
+      restartcollection(g);
+      g->gcstate = GCSpropagate;
+      return 1;
+    }
+    case GCSpropagate: {
+      if (g->gray == NULL) {  /* no more gray objects? */
+        g->gcstate = GCSenteratomic;  /* finish propagate phase */
+        return 0;
+      }
+      else
+        return propagatemark(g);  /* traverse one gray object */
+    }
+    case GCSenteratomic: {
+      lu_mem work = atomic(L);  /* work is what was traversed by 'atomic' */
+      entersweep(L);
+      g->GCestimate = gettotalbytes(g);  /* first estimate */;
+      return work;
+    }
+    case GCSswpallgc: {  /* sweep "regular" objects */
+      return sweepstep(L, g, GCSswpfinobj, &g->finobj);
+    }
+    case GCSswpfinobj: {  /* sweep objects with finalizers */
+      return sweepstep(L, g, GCSswptobefnz, &g->tobefnz);
+    }
+    case GCSswptobefnz: {  /* sweep objects to be finalized */
+      return sweepstep(L, g, GCSswpend, NULL);
+    }
+    case GCSswpend: {  /* finish sweeps */
+      checkSizes(L, g);
+      g->gcstate = GCScallfin;
+      return 0;
+    }
+    case GCScallfin: {  /* call remaining finalizers */
+      if (g->tobefnz && !g->gcemergency) {
+        int n = runafewfinalizers(L, GCFINMAX);
+        return n * GCFINALIZECOST;
+      }
+      else {  /* emergency mode or no more finalizers */
+        g->gcstate = GCSpause;  /* finish collection */
+        return 0;
+      }
+    }
+    default: lua_assert(0); return 0;
+  }
+}
+
+
+/*
+** advances the garbage collector until it reaches a state allowed
+** by 'statemask'
+*/
+void luaC_runtilstate (lua_State *L, int statesmask) {
+  global_State *g = G(L);
+  while (!testbit(statesmask, g->gcstate))
+    singlestep(L);
+}
+
+
+/*
+** Performs a basic incremental step. The debt and step size are
+** converted from bytes to "units of work"; then the function loops
+** running single steps until adding that many units of work or
+** finishing a cycle (pause state). Finally, it sets the debt that
+** controls when next step will be performed.
+*/
+static void incstep (lua_State *L, global_State *g) {
+  int stepmul = (getgcparam(g->gcstepmul) | 1);  /* avoid division by 0 */
+  l_mem debt = (g->GCdebt / WORK2MEM) * stepmul;
+  l_mem stepsize = (g->gcstepsize <= log2maxs(l_mem))
+                 ? ((cast(l_mem, 1) << g->gcstepsize) / WORK2MEM) * stepmul
+                 : MAX_LMEM;  /* overflow; keep maximum value */
+  do {  /* repeat until pause or enough "credit" (negative debt) */
+    lu_mem work = singlestep(L);  /* perform one single step */
+    debt -= work;
+  } while (debt > -stepsize && g->gcstate != GCSpause);
+  if (g->gcstate == GCSpause)
+    setpause(g);  /* pause until next cycle */
+  else {
+    debt = (debt / stepmul) * WORK2MEM;  /* convert 'work units' to bytes */
+    luaE_setdebt(g, debt);
+  }
+}
+
+/*
+** performs a basic GC step if collector is running
+*/
+void luaC_step (lua_State *L) {
+  global_State *g = G(L);
+  lua_assert(!g->gcemergency);
+  if (g->gcrunning) {  /* running? */
+    if(isdecGCmodegen(g))
+      genstep(L, g);
+    else
+      incstep(L, g);
+  }
+}
+
+
+/*
+** Perform a full collection in incremental mode.
+** Before running the collection, check 'keepinvariant'; if it is true,
+** there may be some objects marked as black, so the collector has
+** to sweep all objects to turn them back to white (as white has not
+** changed, nothing will be collected).
+*/
+static void fullinc (lua_State *L, global_State *g) {
+  if (keepinvariant(g))  /* black objects? */
+    entersweep(L); /* sweep everything to turn them back to white */
+  /* finish any pending sweep phase to start a new cycle */
+  luaC_runtilstate(L, bitmask(GCSpause));
+  luaC_runtilstate(L, bitmask(GCScallfin));  /* run up to finalizers */
+  /* estimate must be correct after a full GC cycle */
+  lua_assert(g->GCestimate == gettotalbytes(g));
+  luaC_runtilstate(L, bitmask(GCSpause));  /* finish collection */
+  setpause(g);
+}
+
+
+/*
+** Performs a full GC cycle; if 'isemergency', set a flag to avoid
+** some operations which could change the interpreter state in some
+** unexpected ways (running finalizers and shrinking some structures).
+*/
+void luaC_fullgc (lua_State *L, int isemergency) {
+  global_State *g = G(L);
+  lua_assert(!g->gcemergency);
+  g->gcemergency = isemergency;  /* set flag */
+  if (g->gckind == KGC_INC)
+    fullinc(L, g);
+  else
+    fullgen(L, g);
+  g->gcemergency = 0;
+}
+
+/* }====================================================== */
+
+
diff --git a/test/external/lua-5.4.0/src/lgc.h b/test/external/lua-5.4.0/src/lgc.h
new file mode 100644
index 0000000..b972472
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lgc.h
@@ -0,0 +1,186 @@
+/*
+** $Id: lgc.h $
+** Garbage Collector
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lgc_h
+#define lgc_h
+
+
+#include "lobject.h"
+#include "lstate.h"
+
+/*
+** Collectable objects may have one of three colors: white, which
+** means the object is not marked; gray, which means the
+** object is marked, but its references may be not marked; and
+** black, which means that the object and all its references are marked.
+** The main invariant of the garbage collector, while marking objects,
+** is that a black object can never point to a white one. Moreover,
+** any gray object must be in a "gray list" (gray, grayagain, weak,
+** allweak, ephemeron) so that it can be visited again before finishing
+** the collection cycle. These lists have no meaning when the invariant
+** is not being enforced (e.g., sweep phase).
+*/
+
+
+/*
+** Possible states of the Garbage Collector
+*/
+#define GCSpropagate	0
+#define GCSenteratomic	1
+#define GCSatomic	2
+#define GCSswpallgc	3
+#define GCSswpfinobj	4
+#define GCSswptobefnz	5
+#define GCSswpend	6
+#define GCScallfin	7
+#define GCSpause	8
+
+
+#define issweepphase(g)  \
+	(GCSswpallgc <= (g)->gcstate && (g)->gcstate <= GCSswpend)
+
+
+/*
+** macro to tell when main invariant (white objects cannot point to black
+** ones) must be kept. During a collection, the sweep
+** phase may break the invariant, as objects turned white may point to
+** still-black objects. The invariant is restored when sweep ends and
+** all objects are white again.
+*/
+
+#define keepinvariant(g)	((g)->gcstate <= GCSatomic)
+
+
+/*
+** some useful bit tricks
+*/
+#define resetbits(x,m)		((x) &= cast_byte(~(m)))
+#define setbits(x,m)		((x) |= (m))
+#define testbits(x,m)		((x) & (m))
+#define bitmask(b)		(1<<(b))
+#define bit2mask(b1,b2)		(bitmask(b1) | bitmask(b2))
+#define l_setbit(x,b)		setbits(x, bitmask(b))
+#define resetbit(x,b)		resetbits(x, bitmask(b))
+#define testbit(x,b)		testbits(x, bitmask(b))
+
+
+/*
+** Layout for bit use in 'marked' field. First three bits are
+** used for object "age" in generational mode. Last bit is free
+** to be used by respective objects.
+*/
+#define WHITE0BIT	3  /* object is white (type 0) */
+#define WHITE1BIT	4  /* object is white (type 1) */
+#define BLACKBIT	5  /* object is black */
+#define FINALIZEDBIT	6  /* object has been marked for finalization */
+
+
+
+#define WHITEBITS	bit2mask(WHITE0BIT, WHITE1BIT)
+
+
+#define iswhite(x)      testbits((x)->marked, WHITEBITS)
+#define isblack(x)      testbit((x)->marked, BLACKBIT)
+#define isgray(x)  /* neither white nor black */  \
+	(!testbits((x)->marked, WHITEBITS | bitmask(BLACKBIT)))
+
+#define tofinalize(x)	testbit((x)->marked, FINALIZEDBIT)
+
+#define otherwhite(g)	((g)->currentwhite ^ WHITEBITS)
+#define isdeadm(ow,m)	((m) & (ow))
+#define isdead(g,v)	isdeadm(otherwhite(g), (v)->marked)
+
+#define changewhite(x)	((x)->marked ^= WHITEBITS)
+#define gray2black(x)	l_setbit((x)->marked, BLACKBIT)
+
+#define luaC_white(g)	cast_byte((g)->currentwhite & WHITEBITS)
+
+
+/* object age in generational mode */
+#define G_NEW		0	/* created in current cycle */
+#define G_SURVIVAL	1	/* created in previous cycle */
+#define G_OLD0		2	/* marked old by frw. barrier in this cycle */
+#define G_OLD1		3	/* first full cycle as old */
+#define G_OLD		4	/* really old object (not to be visited) */
+#define G_TOUCHED1	5	/* old object touched this cycle */
+#define G_TOUCHED2	6	/* old object touched in previous cycle */
+
+#define AGEBITS		7  /* all age bits (111) */
+
+#define getage(o)	((o)->marked & AGEBITS)
+#define setage(o,a)  ((o)->marked = cast_byte(((o)->marked & (~AGEBITS)) | a))
+#define isold(o)	(getage(o) > G_SURVIVAL)
+
+#define changeage(o,f,t)  \
+	check_exp(getage(o) == (f), (o)->marked ^= ((f)^(t)))
+
+
+/* Default Values for GC parameters */
+#define LUAI_GENMAJORMUL         100
+#define LUAI_GENMINORMUL         20
+
+/* wait memory to double before starting new cycle */
+#define LUAI_GCPAUSE    200
+
+/*
+** some gc parameters are stored divided by 4 to allow a maximum value
+** up to 1023 in a 'lu_byte'.
+*/
+#define getgcparam(p)	((p) * 4)
+#define setgcparam(p,v)	((p) = (v) / 4)
+
+#define LUAI_GCMUL      100
+
+/* how much to allocate before next GC step (log2) */
+#define LUAI_GCSTEPSIZE 13      /* 8 KB */
+
+
+/*
+** Check whether the declared GC mode is generational. While in
+** generational mode, the collector can go temporarily to incremental
+** mode to improve performance. This is signaled by 'g->lastatomic != 0'.
+*/
+#define isdecGCmodegen(g)	(g->gckind == KGC_GEN || g->lastatomic != 0)
+
+/*
+** Does one step of collection when debt becomes positive. 'pre'/'pos'
+** allows some adjustments to be done only when needed. macro
+** 'condchangemem' is used only for heavy tests (forcing a full
+** GC cycle on every opportunity)
+*/
+#define luaC_condGC(L,pre,pos) \
+	{ if (G(L)->GCdebt > 0) { pre; luaC_step(L); pos;}; \
+	  condchangemem(L,pre,pos); }
+
+/* more often than not, 'pre'/'pos' are empty */
+#define luaC_checkGC(L)		luaC_condGC(L,(void)0,(void)0)
+
+
+#define luaC_barrier(L,p,v) (  \
+	(iscollectable(v) && isblack(p) && iswhite(gcvalue(v))) ?  \
+	luaC_barrier_(L,obj2gco(p),gcvalue(v)) : cast_void(0))
+
+#define luaC_barrierback(L,p,v) (  \
+	(iscollectable(v) && isblack(p) && iswhite(gcvalue(v))) ? \
+	luaC_barrierback_(L,p) : cast_void(0))
+
+#define luaC_objbarrier(L,p,o) (  \
+	(isblack(p) && iswhite(o)) ? \
+	luaC_barrier_(L,obj2gco(p),obj2gco(o)) : cast_void(0))
+
+LUAI_FUNC void luaC_fix (lua_State *L, GCObject *o);
+LUAI_FUNC void luaC_freeallobjects (lua_State *L);
+LUAI_FUNC void luaC_step (lua_State *L);
+LUAI_FUNC void luaC_runtilstate (lua_State *L, int statesmask);
+LUAI_FUNC void luaC_fullgc (lua_State *L, int isemergency);
+LUAI_FUNC GCObject *luaC_newobj (lua_State *L, int tt, size_t sz);
+LUAI_FUNC void luaC_barrier_ (lua_State *L, GCObject *o, GCObject *v);
+LUAI_FUNC void luaC_barrierback_ (lua_State *L, GCObject *o);
+LUAI_FUNC void luaC_checkfinalizer (lua_State *L, GCObject *o, Table *mt);
+LUAI_FUNC void luaC_changemode (lua_State *L, int newmode);
+
+
+#endif
diff --git a/test/external/lua-5.4.0/src/liblua.a b/test/external/lua-5.4.0/src/liblua.a
new file mode 100644
index 0000000..9aa32ed
--- /dev/null
+++ b/test/external/lua-5.4.0/src/liblua.a
diff --git a/test/external/lua-5.4.0/src/linit.c b/test/external/lua-5.4.0/src/linit.c
new file mode 100644
index 0000000..69808f8
--- /dev/null
+++ b/test/external/lua-5.4.0/src/linit.c
@@ -0,0 +1,65 @@
+/*
+** $Id: linit.c $
+** Initialization of libraries for lua.c and other clients
+** See Copyright Notice in lua.h
+*/
+
+
+#define linit_c
+#define LUA_LIB
+
+/*
+** If you embed Lua in your program and need to open the standard
+** libraries, call luaL_openlibs in your program. If you need a
+** different set of libraries, copy this file to your project and edit
+** it to suit your needs.
+**
+** You can also *preload* libraries, so that a later 'require' can
+** open the library, which is already linked to the application.
+** For that, do the following code:
+**
+**  luaL_getsubtable(L, LUA_REGISTRYINDEX, LUA_PRELOAD_TABLE);
+**  lua_pushcfunction(L, luaopen_modname);
+**  lua_setfield(L, -2, modname);
+**  lua_pop(L, 1);  // remove PRELOAD table
+*/
+
+#include "lprefix.h"
+
+
+#include <stddef.h>
+
+#include "lua.h"
+
+#include "lualib.h"
+#include "lauxlib.h"
+
+
+/*
+** these libs are loaded by lua.c and are readily available to any Lua
+** program
+*/
+static const luaL_Reg loadedlibs[] = {
+  {LUA_GNAME, luaopen_base},
+  {LUA_LOADLIBNAME, luaopen_package},
+  {LUA_COLIBNAME, luaopen_coroutine},
+  {LUA_TABLIBNAME, luaopen_table},
+  {LUA_IOLIBNAME, luaopen_io},
+  {LUA_OSLIBNAME, luaopen_os},
+  {LUA_STRLIBNAME, luaopen_string},
+  {LUA_MATHLIBNAME, luaopen_math},
+  {LUA_UTF8LIBNAME, luaopen_utf8},
+  {LUA_DBLIBNAME, luaopen_debug},
+  {NULL, NULL}
+};
+
+
+LUALIB_API void luaL_openlibs (lua_State *L) {
+  const luaL_Reg *lib;
+  /* "require" functions from 'loadedlibs' and set results to global table */
+  for (lib = loadedlibs; lib->func; lib++) {
+    luaL_requiref(L, lib->name, lib->func, 1);
+    lua_pop(L, 1);  /* remove lib */
+  }
+}
+
diff --git a/test/external/lua-5.4.0/src/liolib.c b/test/external/lua-5.4.0/src/liolib.c
new file mode 100644
index 0000000..7ac3444
--- /dev/null
+++ b/test/external/lua-5.4.0/src/liolib.c
@@ -0,0 +1,814 @@
+/*
+** $Id: liolib.c $
+** Standard I/O (and system) library
+** See Copyright Notice in lua.h
+*/
+
+#define liolib_c
+#define LUA_LIB
+
+#include "lprefix.h"
+
+
+#include <ctype.h>
+#include <errno.h>
+#include <locale.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+
+
+/*
+** Change this macro to accept other modes for 'fopen' besides
+** the standard ones.
+*/
+#if !defined(l_checkmode)
+
+/* accepted extensions to 'mode' in 'fopen' */
+#if !defined(L_MODEEXT)
+#define L_MODEEXT	"b"
+#endif
+
+/* Check whether 'mode' matches '[rwa]%+?[L_MODEEXT]*' */
+static int l_checkmode (const char *mode) {
+  return (*mode != '\0' && strchr("rwa", *(mode++)) != NULL &&
+         (*mode != '+' || ((void)(++mode), 1)) &&  /* skip if char is '+' */
+         (strspn(mode, L_MODEEXT) == strlen(mode)));  /* check extensions */
+}
+
+#endif
+
+/*
+** {======================================================
+** l_popen spawns a new process connected to the current
+** one through the file streams.
+** =======================================================
+*/
+
+#if !defined(l_popen)		/* { */
+
+#if defined(LUA_USE_POSIX)	/* { */
+
+#define l_popen(L,c,m)		(fflush(NULL), popen(c,m))
+#define l_pclose(L,file)	(pclose(file))
+
+#elif defined(LUA_USE_WINDOWS)	/* }{ */
+
+#define l_popen(L,c,m)		(_popen(c,m))
+#define l_pclose(L,file)	(_pclose(file))
+
+#else				/* }{ */
+
+/* ISO C definitions */
+#define l_popen(L,c,m)  \
+	  ((void)c, (void)m, \
+	  luaL_error(L, "'popen' not supported"), \
+	  (FILE*)0)
+#define l_pclose(L,file)		((void)L, (void)file, -1)
+
+#endif				/* } */
+
+#endif				/* } */
+
+/* }====================================================== */
+
+
+#if !defined(l_getc)		/* { */
+
+#if defined(LUA_USE_POSIX)
+#define l_getc(f)		getc_unlocked(f)
+#define l_lockfile(f)		flockfile(f)
+#define l_unlockfile(f)		funlockfile(f)
+#else
+#define l_getc(f)		getc(f)
+#define l_lockfile(f)		((void)0)
+#define l_unlockfile(f)		((void)0)
+#endif
+
+#endif				/* } */
+
+
+/*
+** {======================================================
+** l_fseek: configuration for longer offsets
+** =======================================================
+*/
+
+#if !defined(l_fseek)		/* { */
+
+#if defined(LUA_USE_POSIX)	/* { */
+
+#include <sys/types.h>
+
+#define l_fseek(f,o,w)		fseeko(f,o,w)
+#define l_ftell(f)		ftello(f)
+#define l_seeknum		off_t
+
+#elif defined(LUA_USE_WINDOWS) && !defined(_CRTIMP_TYPEINFO) \
+   && defined(_MSC_VER) && (_MSC_VER >= 1400)	/* }{ */
+
+/* Windows (but not DDK) and Visual C++ 2005 or higher */
+#define l_fseek(f,o,w)		_fseeki64(f,o,w)
+#define l_ftell(f)		_ftelli64(f)
+#define l_seeknum		__int64
+
+#else				/* }{ */
+
+/* ISO C definitions */
+#define l_fseek(f,o,w)		fseek(f,o,w)
+#define l_ftell(f)		ftell(f)
+#define l_seeknum		long
+
+#endif				/* } */
+
+#endif				/* } */
+
+/* }====================================================== */
+
+
+
+#define IO_PREFIX	"_IO_"
+#define IOPREF_LEN	(sizeof(IO_PREFIX)/sizeof(char) - 1)
+#define IO_INPUT	(IO_PREFIX "input")
+#define IO_OUTPUT	(IO_PREFIX "output")
+
+
+typedef luaL_Stream LStream;
+
+
+#define tolstream(L)	((LStream *)luaL_checkudata(L, 1, LUA_FILEHANDLE))
+
+#define isclosed(p)	((p)->closef == NULL)
+
+
+static int io_type (lua_State *L) {
+  LStream *p;
+  luaL_checkany(L, 1);
+  p = (LStream *)luaL_testudata(L, 1, LUA_FILEHANDLE);
+  if (p == NULL)
+    luaL_pushfail(L);  /* not a file */
+  else if (isclosed(p))
+    lua_pushliteral(L, "closed file");
+  else
+    lua_pushliteral(L, "file");
+  return 1;
+}
+
+
+static int f_tostring (lua_State *L) {
+  LStream *p = tolstream(L);
+  if (isclosed(p))
+    lua_pushliteral(L, "file (closed)");
+  else
+    lua_pushfstring(L, "file (%p)", p->f);
+  return 1;
+}
+
+
+static FILE *tofile (lua_State *L) {
+  LStream *p = tolstream(L);
+  if (isclosed(p))
+    luaL_error(L, "attempt to use a closed file");
+  lua_assert(p->f);
+  return p->f;
+}
+
+
+/*
+** When creating file handles, always creates a 'closed' file handle
+** before opening the actual file; so, if there is a memory error, the
+** handle is in a consistent state.
+*/
+static LStream *newprefile (lua_State *L) {
+  LStream *p = (LStream *)lua_newuserdatauv(L, sizeof(LStream), 0);
+  p->closef = NULL;  /* mark file handle as 'closed' */
+  luaL_setmetatable(L, LUA_FILEHANDLE);
+  return p;
+}
+
+
+/*
+** Calls the 'close' function from a file handle. The 'volatile' avoids
+** a bug in some versions of the Clang compiler (e.g., clang 3.0 for
+** 32 bits).
+*/
+static int aux_close (lua_State *L) {
+  LStream *p = tolstream(L);
+  volatile lua_CFunction cf = p->closef;
+  p->closef = NULL;  /* mark stream as closed */
+  return (*cf)(L);  /* close it */
+}
+
+
+static int f_close (lua_State *L) {
+  tofile(L);  /* make sure argument is an open stream */
+  return aux_close(L);
+}
+
+
+static int io_close (lua_State *L) {
+  if (lua_isnone(L, 1))  /* no argument? */
+    lua_getfield(L, LUA_REGISTRYINDEX, IO_OUTPUT);  /* use default output */
+  return f_close(L);
+}
+
+
+static int f_gc (lua_State *L) {
+  LStream *p = tolstream(L);
+  if (!isclosed(p) && p->f != NULL)
+    aux_close(L);  /* ignore closed and incompletely open files */
+  return 0;
+}
+
+
+/*
+** function to close regular files
+*/
+static int io_fclose (lua_State *L) {
+  LStream *p = tolstream(L);
+  int res = fclose(p->f);
+  return luaL_fileresult(L, (res == 0), NULL);
+}
+
+
+static LStream *newfile (lua_State *L) {
+  LStream *p = newprefile(L);
+  p->f = NULL;
+  p->closef = &io_fclose;
+  return p;
+}
+
+
+static void opencheck (lua_State *L, const char *fname, const char *mode) {
+  LStream *p = newfile(L);
+  p->f = fopen(fname, mode);
+  if (p->f == NULL)
+    luaL_error(L, "cannot open file '%s' (%s)", fname, strerror(errno));
+}
+
+
+static int io_open (lua_State *L) {
+  const char *filename = luaL_checkstring(L, 1);
+  const char *mode = luaL_optstring(L, 2, "r");
+  LStream *p = newfile(L);
+  const char *md = mode;  /* to traverse/check mode */
+  luaL_argcheck(L, l_checkmode(md), 2, "invalid mode");
+  p->f = fopen(filename, mode);
+  return (p->f == NULL) ? luaL_fileresult(L, 0, filename) : 1;
+}
+
+
+/*
+** function to close 'popen' files
+*/
+static int io_pclose (lua_State *L) {
+  LStream *p = tolstream(L);
+  errno = 0;
+  return luaL_execresult(L, l_pclose(L, p->f));
+}
+
+
+static int io_popen (lua_State *L) {
+  const char *filename = luaL_checkstring(L, 1);
+  const char *mode = luaL_optstring(L, 2, "r");
+  LStream *p = newprefile(L);
+  p->f = l_popen(L, filename, mode);
+  p->closef = &io_pclose;
+  return (p->f == NULL) ? luaL_fileresult(L, 0, filename) : 1;
+}
+
+
+static int io_tmpfile (lua_State *L) {
+  LStream *p = newfile(L);
+  p->f = tmpfile();
+  return (p->f == NULL) ? luaL_fileresult(L, 0, NULL) : 1;
+}
+
+
+static FILE *getiofile (lua_State *L, const char *findex) {
+  LStream *p;
+  lua_getfield(L, LUA_REGISTRYINDEX, findex);
+  p = (LStream *)lua_touserdata(L, -1);
+  if (isclosed(p))
+    luaL_error(L, "default %s file is closed", findex + IOPREF_LEN);
+  return p->f;
+}
+
+
+static int g_iofile (lua_State *L, const char *f, const char *mode) {
+  if (!lua_isnoneornil(L, 1)) {
+    const char *filename = lua_tostring(L, 1);
+    if (filename)
+      opencheck(L, filename, mode);
+    else {
+      tofile(L);  /* check that it's a valid file handle */
+      lua_pushvalue(L, 1);
+    }
+    lua_setfield(L, LUA_REGISTRYINDEX, f);
+  }
+  /* return current value */
+  lua_getfield(L, LUA_REGISTRYINDEX, f);
+  return 1;
+}
+
+
+static int io_input (lua_State *L) {
+  return g_iofile(L, IO_INPUT, "r");
+}
+
+
+static int io_output (lua_State *L) {
+  return g_iofile(L, IO_OUTPUT, "w");
+}
+
+
+static int io_readline (lua_State *L);
+
+
+/*
+** maximum number of arguments to 'f:lines'/'io.lines' (it + 3 must fit
+** in the limit for upvalues of a closure)
+*/
+#define MAXARGLINE	250
+
+/*
+** Auxiliary function to create the iteration function for 'lines'.
+** The iteration function is a closure over 'io_readline', with
+** the following upvalues:
+** 1) The file being read (first value in the stack)
+** 2) the number of arguments to read
+** 3) a boolean, true iff file has to be closed when finished ('toclose')
+** *) a variable number of format arguments (rest of the stack)
+*/
+static void aux_lines (lua_State *L, int toclose) {
+  int n = lua_gettop(L) - 1;  /* number of arguments to read */
+  luaL_argcheck(L, n <= MAXARGLINE, MAXARGLINE + 2, "too many arguments");
+  lua_pushvalue(L, 1);  /* file */
+  lua_pushinteger(L, n);  /* number of arguments to read */
+  lua_pushboolean(L, toclose);  /* close/not close file when finished */
+  lua_rotate(L, 2, 3);  /* move the three values to their positions */
+  lua_pushcclosure(L, io_readline, 3 + n);
+}
+
+
+static int f_lines (lua_State *L) {
+  tofile(L);  /* check that it's a valid file handle */
+  aux_lines(L, 0);
+  return 1;
+}
+
+
+/*
+** Return an iteration function for 'io.lines'. If file has to be
+** closed, also returns the file itself as a second result (to be
+** closed as the state at the exit of a generic for).
+*/
+static int io_lines (lua_State *L) {
+  int toclose;
+  if (lua_isnone(L, 1)) lua_pushnil(L);  /* at least one argument */
+  if (lua_isnil(L, 1)) {  /* no file name? */
+    lua_getfield(L, LUA_REGISTRYINDEX, IO_INPUT);  /* get default input */
+    lua_replace(L, 1);  /* put it at index 1 */
+    tofile(L);  /* check that it's a valid file handle */
+    toclose = 0;  /* do not close it after iteration */
+  }
+  else {  /* open a new file */
+    const char *filename = luaL_checkstring(L, 1);
+    opencheck(L, filename, "r");
+    lua_replace(L, 1);  /* put file at index 1 */
+    toclose = 1;  /* close it after iteration */
+  }
+  aux_lines(L, toclose);  /* push iteration function */
+  if (toclose) {
+    lua_pushnil(L);  /* state */
+    lua_pushnil(L);  /* control */
+    lua_pushvalue(L, 1);  /* file is the to-be-closed variable (4th result) */
+    return 4;
+  }
+  else
+    return 1;
+}
+
+
+/*
+** {======================================================
+** READ
+** =======================================================
+*/
+
+
+/* maximum length of a numeral */
+#if !defined (L_MAXLENNUM)
+#define L_MAXLENNUM     200
+#endif
+
+
+/* auxiliary structure used by 'read_number' */
+typedef struct {
+  FILE *f;  /* file being read */
+  int c;  /* current character (look ahead) */
+  int n;  /* number of elements in buffer 'buff' */
+  char buff[L_MAXLENNUM + 1];  /* +1 for ending '\0' */
+} RN;
+
+
+/*
+** Add current char to buffer (if not out of space) and read next one
+*/
+static int nextc (RN *rn) {
+  if (rn->n >= L_MAXLENNUM) {  /* buffer overflow? */
+    rn->buff[0] = '\0';  /* invalidate result */
+    return 0;  /* fail */
+  }
+  else {
+    rn->buff[rn->n++] = rn->c;  /* save current char */
+    rn->c = l_getc(rn->f);  /* read next one */
+    return 1;
+  }
+}
+
+
+/*
+** Accept current char if it is in 'set' (of size 2)
+*/
+static int test2 (RN *rn, const char *set) {
+  if (rn->c == set[0] || rn->c == set[1])
+    return nextc(rn);
+  else return 0;
+}
+
+
+/*
+** Read a sequence of (hex)digits
+*/
+static int readdigits (RN *rn, int hex) {
+  int count = 0;
+  while ((hex ? isxdigit(rn->c) : isdigit(rn->c)) && nextc(rn))
+    count++;
+  return count;
+}
+
+
+/*
+** Read a number: first reads a valid prefix of a numeral into a buffer.
+** Then it calls 'lua_stringtonumber' to check whether the format is
+** correct and to convert it to a Lua number.
+*/
+static int read_number (lua_State *L, FILE *f) {
+  RN rn;
+  int count = 0;
+  int hex = 0;
+  char decp[2];
+  rn.f = f; rn.n = 0;
+  decp[0] = lua_getlocaledecpoint();  /* get decimal point from locale */
+  decp[1] = '.';  /* always accept a dot */
+  l_lockfile(rn.f);
+  do { rn.c = l_getc(rn.f); } while (isspace(rn.c));  /* skip spaces */
+  test2(&rn, "-+");  /* optional sign */
+  if (test2(&rn, "00")) {
+    if (test2(&rn, "xX")) hex = 1;  /* numeral is hexadecimal */
+    else count = 1;  /* count initial '0' as a valid digit */
+  }
+  count += readdigits(&rn, hex);  /* integral part */
+  if (test2(&rn, decp))  /* decimal point? */
+    count += readdigits(&rn, hex);  /* fractional part */
+  if (count > 0 && test2(&rn, (hex ? "pP" : "eE"))) {  /* exponent mark? */
+    test2(&rn, "-+");  /* exponent sign */
+    readdigits(&rn, 0);  /* exponent digits */
+  }
+  ungetc(rn.c, rn.f);  /* unread look-ahead char */
+  l_unlockfile(rn.f);
+  rn.buff[rn.n] = '\0';  /* finish string */
+  if (lua_stringtonumber(L, rn.buff))  /* is this a valid number? */
+    return 1;  /* ok */
+  else {  /* invalid format */
+   lua_pushnil(L);  /* "result" to be removed */
+   return 0;  /* read fails */
+  }
+}
+
+
+static int test_eof (lua_State *L, FILE *f) {
+  int c = getc(f);
+  ungetc(c, f);  /* no-op when c == EOF */
+  lua_pushliteral(L, "");
+  return (c != EOF);
+}
+
+
+static int read_line (lua_State *L, FILE *f, int chop) {
+  luaL_Buffer b;
+  int c;
+  luaL_buffinit(L, &b);
+  do {  /* may need to read several chunks to get whole line */
+    char *buff = luaL_prepbuffer(&b);  /* preallocate buffer space */
+    int i = 0;
+    l_lockfile(f);  /* no memory errors can happen inside the lock */
+    while (i < LUAL_BUFFERSIZE && (c = l_getc(f)) != EOF && c != '\n')
+      buff[i++] = c;  /* read up to end of line or buffer limit */
+    l_unlockfile(f);
+    luaL_addsize(&b, i);
+  } while (c != EOF && c != '\n');  /* repeat until end of line */
+  if (!chop && c == '\n')  /* want a newline and have one? */
+    luaL_addchar(&b, c);  /* add ending newline to result */
+  luaL_pushresult(&b);  /* close buffer */
+  /* return ok if read something (either a newline or something else) */
+  return (c == '\n' || lua_rawlen(L, -1) > 0);
+}
+
+
+static void read_all (lua_State *L, FILE *f) {
+  size_t nr;
+  luaL_Buffer b;
+  luaL_buffinit(L, &b);
+  do {  /* read file in chunks of LUAL_BUFFERSIZE bytes */
+    char *p = luaL_prepbuffer(&b);
+    nr = fread(p, sizeof(char), LUAL_BUFFERSIZE, f);
+    luaL_addsize(&b, nr);
+  } while (nr == LUAL_BUFFERSIZE);
+  luaL_pushresult(&b);  /* close buffer */
+}
+
+
+static int read_chars (lua_State *L, FILE *f, size_t n) {
+  size_t nr;  /* number of chars actually read */
+  char *p;
+  luaL_Buffer b;
+  luaL_buffinit(L, &b);
+  p = luaL_prepbuffsize(&b, n);  /* prepare buffer to read whole block */
+  nr = fread(p, sizeof(char), n, f);  /* try to read 'n' chars */
+  luaL_addsize(&b, nr);
+  luaL_pushresult(&b);  /* close buffer */
+  return (nr > 0);  /* true iff read something */
+}
+
+
+static int g_read (lua_State *L, FILE *f, int first) {
+  int nargs = lua_gettop(L) - 1;
+  int n, success;
+  clearerr(f);
+  if (nargs == 0) {  /* no arguments? */
+    success = read_line(L, f, 1);
+    n = first + 1;  /* to return 1 result */
+  }
+  else {
+    /* ensure stack space for all results and for auxlib's buffer */
+    luaL_checkstack(L, nargs+LUA_MINSTACK, "too many arguments");
+    success = 1;
+    for (n = first; nargs-- && success; n++) {
+      if (lua_type(L, n) == LUA_TNUMBER) {
+        size_t l = (size_t)luaL_checkinteger(L, n);
+        success = (l == 0) ? test_eof(L, f) : read_chars(L, f, l);
+      }
+      else {
+        const char *p = luaL_checkstring(L, n);
+        if (*p == '*') p++;  /* skip optional '*' (for compatibility) */
+        switch (*p) {
+          case 'n':  /* number */
+            success = read_number(L, f);
+            break;
+          case 'l':  /* line */
+            success = read_line(L, f, 1);
+            break;
+          case 'L':  /* line with end-of-line */
+            success = read_line(L, f, 0);
+            break;
+          case 'a':  /* file */
+            read_all(L, f);  /* read entire file */
+            success = 1; /* always success */
+            break;
+          default:
+            return luaL_argerror(L, n, "invalid format");
+        }
+      }
+    }
+  }
+  if (ferror(f))
+    return luaL_fileresult(L, 0, NULL);
+  if (!success) {
+    lua_pop(L, 1);  /* remove last result */
+    luaL_pushfail(L);  /* push nil instead */
+  }
+  return n - first;
+}
+
+
+static int io_read (lua_State *L) {
+  return g_read(L, getiofile(L, IO_INPUT), 1);
+}
+
+
+static int f_read (lua_State *L) {
+  return g_read(L, tofile(L), 2);
+}
+
+
+/*
+** Iteration function for 'lines'.
+*/
+static int io_readline (lua_State *L) {
+  LStream *p = (LStream *)lua_touserdata(L, lua_upvalueindex(1));
+  int i;
+  int n = (int)lua_tointeger(L, lua_upvalueindex(2));
+  if (isclosed(p))  /* file is already closed? */
+    return luaL_error(L, "file is already closed");
+  lua_settop(L , 1);
+  luaL_checkstack(L, n, "too many arguments");
+  for (i = 1; i <= n; i++)  /* push arguments to 'g_read' */
+    lua_pushvalue(L, lua_upvalueindex(3 + i));
+  n = g_read(L, p->f, 2);  /* 'n' is number of results */
+  lua_assert(n > 0);  /* should return at least a nil */
+  if (lua_toboolean(L, -n))  /* read at least one value? */
+    return n;  /* return them */
+  else {  /* first result is false: EOF or error */
+    if (n > 1) {  /* is there error information? */
+      /* 2nd result is error message */
+      return luaL_error(L, "%s", lua_tostring(L, -n + 1));
+    }
+    if (lua_toboolean(L, lua_upvalueindex(3))) {  /* generator created file? */
+      lua_settop(L, 0);  /* clear stack */
+      lua_pushvalue(L, lua_upvalueindex(1));  /* push file at index 1 */
+      aux_close(L);  /* close it */
+    }
+    return 0;
+  }
+}
+
+/* }====================================================== */
+
+
+static int g_write (lua_State *L, FILE *f, int arg) {
+  int nargs = lua_gettop(L) - arg;
+  int status = 1;
+  for (; nargs--; arg++) {
+    if (lua_type(L, arg) == LUA_TNUMBER) {
+      /* optimization: could be done exactly as for strings */
+      int len = lua_isinteger(L, arg)
+                ? fprintf(f, LUA_INTEGER_FMT,
+                             (LUAI_UACINT)lua_tointeger(L, arg))
+                : fprintf(f, LUA_NUMBER_FMT,
+                             (LUAI_UACNUMBER)lua_tonumber(L, arg));
+      status = status && (len > 0);
+    }
+    else {
+      size_t l;
+      const char *s = luaL_checklstring(L, arg, &l);
+      status = status && (fwrite(s, sizeof(char), l, f) == l);
+    }
+  }
+  if (status) return 1;  /* file handle already on stack top */
+  else return luaL_fileresult(L, status, NULL);
+}
+
+
+static int io_write (lua_State *L) {
+  return g_write(L, getiofile(L, IO_OUTPUT), 1);
+}
+
+
+static int f_write (lua_State *L) {
+  FILE *f = tofile(L);
+  lua_pushvalue(L, 1);  /* push file at the stack top (to be returned) */
+  return g_write(L, f, 2);
+}
+
+
+static int f_seek (lua_State *L) {
+  static const int mode[] = {SEEK_SET, SEEK_CUR, SEEK_END};
+  static const char *const modenames[] = {"set", "cur", "end", NULL};
+  FILE *f = tofile(L);
+  int op = luaL_checkoption(L, 2, "cur", modenames);
+  lua_Integer p3 = luaL_optinteger(L, 3, 0);
+  l_seeknum offset = (l_seeknum)p3;
+  luaL_argcheck(L, (lua_Integer)offset == p3, 3,
+                  "not an integer in proper range");
+  op = l_fseek(f, offset, mode[op]);
+  if (op)
+    return luaL_fileresult(L, 0, NULL);  /* error */
+  else {
+    lua_pushinteger(L, (lua_Integer)l_ftell(f));
+    return 1;
+  }
+}
+
+
+static int f_setvbuf (lua_State *L) {
+  static const int mode[] = {_IONBF, _IOFBF, _IOLBF};
+  static const char *const modenames[] = {"no", "full", "line", NULL};
+  FILE *f = tofile(L);
+  int op = luaL_checkoption(L, 2, NULL, modenames);
+  lua_Integer sz = luaL_optinteger(L, 3, LUAL_BUFFERSIZE);
+  int res = setvbuf(f, NULL, mode[op], (size_t)sz);
+  return luaL_fileresult(L, res == 0, NULL);
+}
+
+
+
+static int io_flush (lua_State *L) {
+  return luaL_fileresult(L, fflush(getiofile(L, IO_OUTPUT)) == 0, NULL);
+}
+
+
+static int f_flush (lua_State *L) {
+  return luaL_fileresult(L, fflush(tofile(L)) == 0, NULL);
+}
+
+
+/*
+** functions for 'io' library
+*/
+static const luaL_Reg iolib[] = {
+  {"close", io_close},
+  {"flush", io_flush},
+  {"input", io_input},
+  {"lines", io_lines},
+  {"open", io_open},
+  {"output", io_output},
+  {"popen", io_popen},
+  {"read", io_read},
+  {"tmpfile", io_tmpfile},
+  {"type", io_type},
+  {"write", io_write},
+  {NULL, NULL}
+};
+
+
+/*
+** methods for file handles
+*/
+static const luaL_Reg meth[] = {
+  {"read", f_read},
+  {"write", f_write},
+  {"lines", f_lines},
+  {"flush", f_flush},
+  {"seek", f_seek},
+  {"close", f_close},
+  {"setvbuf", f_setvbuf},
+  {NULL, NULL}
+};
+
+
+/*
+** metamethods for file handles
+*/
+static const luaL_Reg metameth[] = {
+  {"__index", NULL},  /* place holder */
+  {"__gc", f_gc},
+  {"__close", f_gc},
+  {"__tostring", f_tostring},
+  {NULL, NULL}
+};
+
+
+static void createmeta (lua_State *L) {
+  luaL_newmetatable(L, LUA_FILEHANDLE);  /* metatable for file handles */
+  luaL_setfuncs(L, metameth, 0);  /* add metamethods to new metatable */
+  luaL_newlibtable(L, meth);  /* create method table */
+  luaL_setfuncs(L, meth, 0);  /* add file methods to method table */
+  lua_setfield(L, -2, "__index");  /* metatable.__index = method table */
+  lua_pop(L, 1);  /* pop metatable */
+}
+
+
+/*
+** function to (not) close the standard files stdin, stdout, and stderr
+*/
+static int io_noclose (lua_State *L) {
+  LStream *p = tolstream(L);
+  p->closef = &io_noclose;  /* keep file opened */
+  luaL_pushfail(L);
+  lua_pushliteral(L, "cannot close standard file");
+  return 2;
+}
+
+
+static void createstdfile (lua_State *L, FILE *f, const char *k,
+                           const char *fname) {
+  LStream *p = newprefile(L);
+  p->f = f;
+  p->closef = &io_noclose;
+  if (k != NULL) {
+    lua_pushvalue(L, -1);
+    lua_setfield(L, LUA_REGISTRYINDEX, k);  /* add file to registry */
+  }
+  lua_setfield(L, -2, fname);  /* add file to module */
+}
+
+
+LUAMOD_API int luaopen_io (lua_State *L) {
+  luaL_newlib(L, iolib);  /* new module */
+  createmeta(L);
+  /* create (and set) default files */
+  createstdfile(L, stdin, IO_INPUT, "stdin");
+  createstdfile(L, stdout, IO_OUTPUT, "stdout");
+  createstdfile(L, stderr, NULL, "stderr");
+  return 1;
+}
+
diff --git a/test/external/lua-5.4.0/src/ljumptab.h b/test/external/lua-5.4.0/src/ljumptab.h
new file mode 100644
index 0000000..8306f25
--- /dev/null
+++ b/test/external/lua-5.4.0/src/ljumptab.h
@@ -0,0 +1,112 @@
+/*
+** $Id: ljumptab.h $
+** Jump Table for the Lua interpreter
+** See Copyright Notice in lua.h
+*/
+
+
+#undef vmdispatch
+#undef vmcase
+#undef vmbreak
+
+#define vmdispatch(x)     goto *disptab[x];
+
+#define vmcase(l)     L_##l:
+
+#define vmbreak		vmfetch(); vmdispatch(GET_OPCODE(i));
+
+
+static const void *const disptab[NUM_OPCODES] = {
+
+#if 0
+** you can update the following list with this command:
+**
+**  sed -n '/^OP_/\!d; s/OP_/\&\&L_OP_/ ; s/,.*/,/ ; s/\/.*// ; p'  lopcodes.h
+**
+#endif
+
+&&L_OP_MOVE,
+&&L_OP_LOADI,
+&&L_OP_LOADF,
+&&L_OP_LOADK,
+&&L_OP_LOADKX,
+&&L_OP_LOADFALSE,
+&&L_OP_LFALSESKIP,
+&&L_OP_LOADTRUE,
+&&L_OP_LOADNIL,
+&&L_OP_GETUPVAL,
+&&L_OP_SETUPVAL,
+&&L_OP_GETTABUP,
+&&L_OP_GETTABLE,
+&&L_OP_GETI,
+&&L_OP_GETFIELD,
+&&L_OP_SETTABUP,
+&&L_OP_SETTABLE,
+&&L_OP_SETI,
+&&L_OP_SETFIELD,
+&&L_OP_NEWTABLE,
+&&L_OP_SELF,
+&&L_OP_ADDI,
+&&L_OP_ADDK,
+&&L_OP_SUBK,
+&&L_OP_MULK,
+&&L_OP_MODK,
+&&L_OP_POWK,
+&&L_OP_DIVK,
+&&L_OP_IDIVK,
+&&L_OP_BANDK,
+&&L_OP_BORK,
+&&L_OP_BXORK,
+&&L_OP_SHRI,
+&&L_OP_SHLI,
+&&L_OP_ADD,
+&&L_OP_SUB,
+&&L_OP_MUL,
+&&L_OP_MOD,
+&&L_OP_POW,
+&&L_OP_DIV,
+&&L_OP_IDIV,
+&&L_OP_BAND,
+&&L_OP_BOR,
+&&L_OP_BXOR,
+&&L_OP_SHL,
+&&L_OP_SHR,
+&&L_OP_MMBIN,
+&&L_OP_MMBINI,
+&&L_OP_MMBINK,
+&&L_OP_UNM,
+&&L_OP_BNOT,
+&&L_OP_NOT,
+&&L_OP_LEN,
+&&L_OP_CONCAT,
+&&L_OP_CLOSE,
+&&L_OP_TBC,
+&&L_OP_JMP,
+&&L_OP_EQ,
+&&L_OP_LT,
+&&L_OP_LE,
+&&L_OP_EQK,
+&&L_OP_EQI,
+&&L_OP_LTI,
+&&L_OP_LEI,
+&&L_OP_GTI,
+&&L_OP_GEI,
+&&L_OP_TEST,
+&&L_OP_TESTSET,
+&&L_OP_CALL,
+&&L_OP_TAILCALL,
+&&L_OP_RETURN,
+&&L_OP_RETURN0,
+&&L_OP_RETURN1,
+&&L_OP_FORLOOP,
+&&L_OP_FORPREP,
+&&L_OP_TFORPREP,
+&&L_OP_TFORCALL,
+&&L_OP_TFORLOOP,
+&&L_OP_SETLIST,
+&&L_OP_CLOSURE,
+&&L_OP_VARARG,
+&&L_OP_VARARGPREP,
+&&L_OP_EXTRAARG
+
+};
diff --git a/test/external/lua-5.4.0/src/llex.c b/test/external/lua-5.4.0/src/llex.c
new file mode 100644
index 0000000..90a7951
--- /dev/null
+++ b/test/external/lua-5.4.0/src/llex.c
@@ -0,0 +1,578 @@
+/*
+** $Id: llex.c $
+** Lexical Analyzer
+** See Copyright Notice in lua.h
+*/
+
+#define llex_c
+#define LUA_CORE
+
+#include "lprefix.h"
+
+
+#include <locale.h>
+#include <string.h>
+
+#include "lua.h"
+
+#include "lctype.h"
+#include "ldebug.h"
+#include "ldo.h"
+#include "lgc.h"
+#include "llex.h"
+#include "lobject.h"
+#include "lparser.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "lzio.h"
+
+
+
+#define next(ls)	(ls->current = zgetc(ls->z))
+
+
+
+#define currIsNewline(ls)	(ls->current == '\n' || ls->current == '\r')
+
+
+/* ORDER RESERVED */
+static const char *const luaX_tokens [] = {
+    "and", "break", "do", "else", "elseif",
+    "end", "false", "for", "function", "goto", "if",
+    "in", "local", "nil", "not", "or", "repeat",
+    "return", "then", "true", "until", "while",
+    "//", "..", "...", "==", ">=", "<=", "~=",
+    "<<", ">>", "::", "<eof>",
+    "<number>", "<integer>", "<name>", "<string>"
+};
+
+
+#define save_and_next(ls) (save(ls, ls->current), next(ls))
+
+
+static l_noret lexerror (LexState *ls, const char *msg, int token);
+
+
+static void save (LexState *ls, int c) {
+  Mbuffer *b = ls->buff;
+  if (luaZ_bufflen(b) + 1 > luaZ_sizebuffer(b)) {
+    size_t newsize;
+    if (luaZ_sizebuffer(b) >= MAX_SIZE/2)
+      lexerror(ls, "lexical element too long", 0);
+    newsize = luaZ_sizebuffer(b) * 2;
+    luaZ_resizebuffer(ls->L, b, newsize);
+  }
+  b->buffer[luaZ_bufflen(b)++] = cast_char(c);
+}
+
+
+void luaX_init (lua_State *L) {
+  int i;
+  TString *e = luaS_newliteral(L, LUA_ENV);  /* create env name */
+  luaC_fix(L, obj2gco(e));  /* never collect this name */
+  for (i=0; i<NUM_RESERVED; i++) {
+    TString *ts = luaS_new(L, luaX_tokens[i]);
+    luaC_fix(L, obj2gco(ts));  /* reserved words are never collected */
+    ts->extra = cast_byte(i+1);  /* reserved word */
+  }
+}
+
+
+const char *luaX_token2str (LexState *ls, int token) {
+  if (token < FIRST_RESERVED) {  /* single-byte symbols? */
+    lua_assert(token == cast_uchar(token));
+    if (lisprint(token))
+      return luaO_pushfstring(ls->L, "'%c'", token);
+    else  /* control character */
+      return luaO_pushfstring(ls->L, "'<\\%d>'", token);
+  }
+  else {
+    const char *s = luaX_tokens[token - FIRST_RESERVED];
+    if (token < TK_EOS)  /* fixed format (symbols and reserved words)? */
+      return luaO_pushfstring(ls->L, "'%s'", s);
+    else  /* names, strings, and numerals */
+      return s;
+  }
+}
+
+
+static const char *txtToken (LexState *ls, int token) {
+  switch (token) {
+    case TK_NAME: case TK_STRING:
+    case TK_FLT: case TK_INT:
+      save(ls, '\0');
+      return luaO_pushfstring(ls->L, "'%s'", luaZ_buffer(ls->buff));
+    default:
+      return luaX_token2str(ls, token);
+  }
+}
+
+
+static l_noret lexerror (LexState *ls, const char *msg, int token) {
+  msg = luaG_addinfo(ls->L, msg, ls->source, ls->linenumber);
+  if (token)
+    luaO_pushfstring(ls->L, "%s near %s", msg, txtToken(ls, token));
+  luaD_throw(ls->L, LUA_ERRSYNTAX);
+}
+
+
+l_noret luaX_syntaxerror (LexState *ls, const char *msg) {
+  lexerror(ls, msg, ls->t.token);
+}
+
+
+/*
+** creates a new string and anchors it in scanner's table so that
+** it will not be collected until the end of the compilation
+** (by that time it should be anchored somewhere)
+*/
+TString *luaX_newstring (LexState *ls, const char *str, size_t l) {
+  lua_State *L = ls->L;
+  TValue *o;  /* entry for 'str' */
+  TString *ts = luaS_newlstr(L, str, l);  /* create new string */
+  setsvalue2s(L, L->top++, ts);  /* temporarily anchor it in stack */
+  o = luaH_set(L, ls->h, s2v(L->top - 1));
+  if (isempty(o)) {  /* not in use yet? */
+    /* boolean value does not need GC barrier;
+       table is not a metatable, so it does not need to invalidate cache */
+    setbtvalue(o);  /* t[string] = true */
+    luaC_checkGC(L);
+  }
+  else {  /* string already present */
+    ts = keystrval(nodefromval(o));  /* re-use value previously stored */
+  }
+  L->top--;  /* remove string from stack */
+  return ts;
+}
+
+
+/*
+** increment line number and skips newline sequence (any of
+** \n, \r, \n\r, or \r\n)
+*/
+static void inclinenumber (LexState *ls) {
+  int old = ls->current;
+  lua_assert(currIsNewline(ls));
+  next(ls);  /* skip '\n' or '\r' */
+  if (currIsNewline(ls) && ls->current != old)
+    next(ls);  /* skip '\n\r' or '\r\n' */
+  if (++ls->linenumber >= MAX_INT)
+    lexerror(ls, "chunk has too many lines", 0);
+}
+
+
+void luaX_setinput (lua_State *L, LexState *ls, ZIO *z, TString *source,
+                    int firstchar) {
+  ls->t.token = 0;
+  ls->L = L;
+  ls->current = firstchar;
+  ls->lookahead.token = TK_EOS;  /* no look-ahead token */
+  ls->z = z;
+  ls->fs = NULL;
+  ls->linenumber = 1;
+  ls->lastline = 1;
+  ls->source = source;
+  ls->envn = luaS_newliteral(L, LUA_ENV);  /* get env name */
+  luaZ_resizebuffer(ls->L, ls->buff, LUA_MINBUFFER);  /* initialize buffer */
+}
+
+
+
+/*
+** =======================================================
+** LEXICAL ANALYZER
+** =======================================================
+*/
+
+
+static int check_next1 (LexState *ls, int c) {
+  if (ls->current == c) {
+    next(ls);
+    return 1;
+  }
+  else return 0;
+}
+
+
+/*
+** Check whether current char is in set 'set' (with two chars) and
+** saves it
+*/
+static int check_next2 (LexState *ls, const char *set) {
+  lua_assert(set[2] == '\0');
+  if (ls->current == set[0] || ls->current == set[1]) {
+    save_and_next(ls);
+    return 1;
+  }
+  else return 0;
+}
+
+
+/* LUA_NUMBER */
+/*
+** This function is quite liberal in what it accepts, as 'luaO_str2num'
+** will reject ill-formed numerals. Roughly, it accepts the following
+** pattern:
+**
+**   %d(%x|%.|([Ee][+-]?))* | 0[Xx](%x|%.|([Pp][+-]?))*
+**
+** The only tricky part is to accept [+-] only after a valid exponent
+** mark, to avoid reading '3-4' or '0xe+1' as a single number.
+**
+** The caller might have already read an initial dot.
+*/
+static int read_numeral (LexState *ls, SemInfo *seminfo) {
+  TValue obj;
+  const char *expo = "Ee";
+  int first = ls->current;
+  lua_assert(lisdigit(ls->current));
+  save_and_next(ls);
+  if (first == '0' && check_next2(ls, "xX"))  /* hexadecimal? */
+    expo = "Pp";
+  for (;;) {
+    if (check_next2(ls, expo))  /* exponent mark? */
+      check_next2(ls, "-+");  /* optional exponent sign */
+    else if (lisxdigit(ls->current) || ls->current == '.')  /* '%x|%.' */
+      save_and_next(ls);
+    else break;
+  }
+  if (lislalpha(ls->current))  /* is numeral touching a letter? */
+    save_and_next(ls);  /* force an error */
+  save(ls, '\0');
+  if (luaO_str2num(luaZ_buffer(ls->buff), &obj) == 0)  /* format error? */
+    lexerror(ls, "malformed number", TK_FLT);
+  if (ttisinteger(&obj)) {
+    seminfo->i = ivalue(&obj);
+    return TK_INT;
+  }
+  else {
+    lua_assert(ttisfloat(&obj));
+    seminfo->r = fltvalue(&obj);
+    return TK_FLT;
+  }
+}
+
+
+/*
+** reads a sequence '[=*[' or ']=*]', leaving the last bracket.
+** If sequence is well formed, return its number of '='s + 2; otherwise,
+** return 1 if there is no '='s or 0 otherwise (an unfinished '[==...').
+*/
+static size_t skip_sep (LexState *ls) {
+  size_t count = 0;
+  int s = ls->current;
+  lua_assert(s == '[' || s == ']');
+  save_and_next(ls);
+  while (ls->current == '=') {
+    save_and_next(ls);
+    count++;
+  }
+  return (ls->current == s) ? count + 2
+         : (count == 0) ? 1
+         : 0;
+}
+
+
+static void read_long_string (LexState *ls, SemInfo *seminfo, size_t sep) {
+  int line = ls->linenumber;  /* initial line (for error message) */
+  save_and_next(ls);  /* skip 2nd '[' */
+  if (currIsNewline(ls))  /* string starts with a newline? */
+    inclinenumber(ls);  /* skip it */
+  for (;;) {
+    switch (ls->current) {
+      case EOZ: {  /* error */
+        const char *what = (seminfo ? "string" : "comment");
+        const char *msg = luaO_pushfstring(ls->L,
+                     "unfinished long %s (starting at line %d)", what, line);
+        lexerror(ls, msg, TK_EOS);
+        break;  /* to avoid warnings */
+      }
+      case ']': {
+        if (skip_sep(ls) == sep) {
+          save_and_next(ls);  /* skip 2nd ']' */
+          goto endloop;
+        }
+        break;
+      }
+      case '\n': case '\r': {
+        save(ls, '\n');
+        inclinenumber(ls);
+        if (!seminfo) luaZ_resetbuffer(ls->buff);  /* avoid wasting space */
+        break;
+      }
+      default: {
+        if (seminfo) save_and_next(ls);
+        else next(ls);
+      }
+    }
+  } endloop:
+  if (seminfo)
+    seminfo->ts = luaX_newstring(ls, luaZ_buffer(ls->buff) + sep,
+                                     luaZ_bufflen(ls->buff) - 2 * sep);
+}
+
+
+static void esccheck (LexState *ls, int c, const char *msg) {
+  if (!c) {
+    if (ls->current != EOZ)
+      save_and_next(ls);  /* add current to buffer for error message */
+    lexerror(ls, msg, TK_STRING);
+  }
+}
+
+
+static int gethexa (LexState *ls) {
+  save_and_next(ls);
+  esccheck (ls, lisxdigit(ls->current), "hexadecimal digit expected");
+  return luaO_hexavalue(ls->current);
+}
+
+
+static int readhexaesc (LexState *ls) {
+  int r = gethexa(ls);
+  r = (r << 4) + gethexa(ls);
+  luaZ_buffremove(ls->buff, 2);  /* remove saved chars from buffer */
+  return r;
+}
+
+
+static unsigned long readutf8esc (LexState *ls) {
+  unsigned long r;
+  int i = 4;  /* chars to be removed: '\', 'u', '{', and first digit */
+  save_and_next(ls);  /* skip 'u' */
+  esccheck(ls, ls->current == '{', "missing '{'");
+  r = gethexa(ls);  /* must have at least one digit */
+  while (cast_void(save_and_next(ls)), lisxdigit(ls->current)) {
+    i++;
+    esccheck(ls, r <= (0x7FFFFFFFu >> 4), "UTF-8 value too large");
+    r = (r << 4) + luaO_hexavalue(ls->current);
+  }
+  esccheck(ls, ls->current == '}', "missing '}'");
+  next(ls);  /* skip '}' */
+  luaZ_buffremove(ls->buff, i);  /* remove saved chars from buffer */
+  return r;
+}
+
+
+static void utf8esc (LexState *ls) {
+  char buff[UTF8BUFFSZ];
+  int n = luaO_utf8esc(buff, readutf8esc(ls));
+  for (; n > 0; n--)  /* add 'buff' to string */
+    save(ls, buff[UTF8BUFFSZ - n]);
+}
+
+
+static int readdecesc (LexState *ls) {
+  int i;
+  int r = 0;  /* result accumulator */
+  for (i = 0; i < 3 && lisdigit(ls->current); i++) {  /* read up to 3 digits */
+    r = 10*r + ls->current - '0';
+    save_and_next(ls);
+  }
+  esccheck(ls, r <= UCHAR_MAX, "decimal escape too large");
+  luaZ_buffremove(ls->buff, i);  /* remove read digits from buffer */
+  return r;
+}
+
+
+static void read_string (LexState *ls, int del, SemInfo *seminfo) {
+  save_and_next(ls);  /* keep delimiter (for error messages) */
+  while (ls->current != del) {
+    switch (ls->current) {
+      case EOZ:
+        lexerror(ls, "unfinished string", TK_EOS);
+        break;  /* to avoid warnings */
+      case '\n':
+      case '\r':
+        lexerror(ls, "unfinished string", TK_STRING);
+        break;  /* to avoid warnings */
+      case '\\': {  /* escape sequences */
+        int c;  /* final character to be saved */
+        save_and_next(ls);  /* keep '\\' for error messages */
+        switch (ls->current) {
+          case 'a': c = '\a'; goto read_save;
+          case 'b': c = '\b'; goto read_save;
+          case 'f': c = '\f'; goto read_save;
+          case 'n': c = '\n'; goto read_save;
+          case 'r': c = '\r'; goto read_save;
+          case 't': c = '\t'; goto read_save;
+          case 'v': c = '\v'; goto read_save;
+          case 'x': c = readhexaesc(ls); goto read_save;
+          case 'u': utf8esc(ls);  goto no_save;
+          case '\n': case '\r':
+            inclinenumber(ls); c = '\n'; goto only_save;
+          case '\\': case '\"': case '\'':
+            c = ls->current; goto read_save;
+          case EOZ: goto no_save;  /* will raise an error next loop */
+          case 'z': {  /* zap following span of spaces */
+            luaZ_buffremove(ls->buff, 1);  /* remove '\\' */
+            next(ls);  /* skip the 'z' */
+            while (lisspace(ls->current)) {
+              if (currIsNewline(ls)) inclinenumber(ls);
+              else next(ls);
+            }
+            goto no_save;
+          }
+          default: {
+            esccheck(ls, lisdigit(ls->current), "invalid escape sequence");
+            c = readdecesc(ls);  /* digital escape '\ddd' */
+            goto only_save;
+          }
+        }
+       read_save:
+         next(ls);
+         /* go through */
+       only_save:
+         luaZ_buffremove(ls->buff, 1);  /* remove '\\' */
+         save(ls, c);
+         /* go through */
+       no_save: break;
+      }
+      default:
+        save_and_next(ls);
+    }
+  }
+  save_and_next(ls);  /* skip delimiter */
+  seminfo->ts = luaX_newstring(ls, luaZ_buffer(ls->buff) + 1,
+                                   luaZ_bufflen(ls->buff) - 2);
+}
+
+
+static int llex (LexState *ls, SemInfo *seminfo) {
+  luaZ_resetbuffer(ls->buff);
+  for (;;) {
+    switch (ls->current) {
+      case '\n': case '\r': {  /* line breaks */
+        inclinenumber(ls);
+        break;
+      }
+      case ' ': case '\f': case '\t': case '\v': {  /* spaces */
+        next(ls);
+        break;
+      }
+      case '-': {  /* '-' or '--' (comment) */
+        next(ls);
+        if (ls->current != '-') return '-';
+        /* else is a comment */
+        next(ls);
+        if (ls->current == '[') {  /* long comment? */
+          size_t sep = skip_sep(ls);
+          luaZ_resetbuffer(ls->buff);  /* 'skip_sep' may dirty the buffer */
+          if (sep >= 2) {
+            read_long_string(ls, NULL, sep);  /* skip long comment */
+            luaZ_resetbuffer(ls->buff);  /* previous call may dirty the buff. */
+            break;
+          }
+        }
+        /* else short comment */
+        while (!currIsNewline(ls) && ls->current != EOZ)
+          next(ls);  /* skip until end of line (or end of file) */
+        break;
+      }
+      case '[': {  /* long string or simply '[' */
+        size_t sep = skip_sep(ls);
+        if (sep >= 2) {
+          read_long_string(ls, seminfo, sep);
+          return TK_STRING;
+        }
+        else if (sep == 0)  /* '[=...' missing second bracket? */
+          lexerror(ls, "invalid long string delimiter", TK_STRING);
+        return '[';
+      }
+      case '=': {
+        next(ls);
+        if (check_next1(ls, '=')) return TK_EQ;
+        else return '=';
+      }
+      case '<': {
+        next(ls);
+        if (check_next1(ls, '=')) return TK_LE;
+        else if (check_next1(ls, '<')) return TK_SHL;
+        else return '<';
+      }
+      case '>': {
+        next(ls);
+        if (check_next1(ls, '=')) return TK_GE;
+        else if (check_next1(ls, '>')) return TK_SHR;
+        else return '>';
+      }
+      case '/': {
+        next(ls);
+        if (check_next1(ls, '/')) return TK_IDIV;
+        else return '/';
+      }
+      case '~': {
+        next(ls);
+        if (check_next1(ls, '=')) return TK_NE;
+        else return '~';
+      }
+      case ':': {
+        next(ls);
+        if (check_next1(ls, ':')) return TK_DBCOLON;
+        else return ':';
+      }
+      case '"': case '\'': {  /* short literal strings */
+        read_string(ls, ls->current, seminfo);
+        return TK_STRING;
+      }
+      case '.': {  /* '.', '..', '...', or number */
+        save_and_next(ls);
+        if (check_next1(ls, '.')) {
+          if (check_next1(ls, '.'))
+            return TK_DOTS;   /* '...' */
+          else return TK_CONCAT;   /* '..' */
+        }
+        else if (!lisdigit(ls->current)) return '.';
+        else return read_numeral(ls, seminfo);
+      }
+      case '0': case '1': case '2': case '3': case '4':
+      case '5': case '6': case '7': case '8': case '9': {
+        return read_numeral(ls, seminfo);
+      }
+      case EOZ: {
+        return TK_EOS;
+      }
+      default: {
+        if (lislalpha(ls->current)) {  /* identifier or reserved word? */
+          TString *ts;
+          do {
+            save_and_next(ls);
+          } while (lislalnum(ls->current));
+          ts = luaX_newstring(ls, luaZ_buffer(ls->buff),
+                                  luaZ_bufflen(ls->buff));
+          seminfo->ts = ts;
+          if (isreserved(ts))  /* reserved word? */
+            return ts->extra - 1 + FIRST_RESERVED;
+          else {
+            return TK_NAME;
+          }
+        }
+        else {  /* single-char tokens (+ - / ...) */
+          int c = ls->current;
+          next(ls);
+          return c;
+        }
+      }
+    }
+  }
+}
+
+
+void luaX_next (LexState *ls) {
+  ls->lastline = ls->linenumber;
+  if (ls->lookahead.token != TK_EOS) {  /* is there a look-ahead token? */
+    ls->t = ls->lookahead;  /* use this one */
+    ls->lookahead.token = TK_EOS;  /* and discharge it */
+  }
+  else
+    ls->t.token = llex(ls, &ls->t.seminfo);  /* read next token */
+}
+
+
+int luaX_lookahead (LexState *ls) {
+  lua_assert(ls->lookahead.token == TK_EOS);
+  ls->lookahead.token = llex(ls, &ls->lookahead.seminfo);
+  return ls->lookahead.token;
+}
+
diff --git a/test/external/lua-5.4.0/src/llex.h b/test/external/lua-5.4.0/src/llex.h
new file mode 100644
index 0000000..d1a4cba
--- /dev/null
+++ b/test/external/lua-5.4.0/src/llex.h
@@ -0,0 +1,85 @@
+/*
+** $Id: llex.h $
+** Lexical Analyzer
+** See Copyright Notice in lua.h
+*/
+
+#ifndef llex_h
+#define llex_h
+
+#include "lobject.h"
+#include "lzio.h"
+
+
+#define FIRST_RESERVED	257
+
+
+#if !defined(LUA_ENV)
+#define LUA_ENV		"_ENV"
+#endif
+
+
+/*
+* WARNING: if you change the order of this enumeration,
+* grep "ORDER RESERVED"
+*/
+enum RESERVED {
+  /* terminal symbols denoted by reserved words */
+  TK_AND = FIRST_RESERVED, TK_BREAK,
+  TK_DO, TK_ELSE, TK_ELSEIF, TK_END, TK_FALSE, TK_FOR, TK_FUNCTION,
+  TK_GOTO, TK_IF, TK_IN, TK_LOCAL, TK_NIL, TK_NOT, TK_OR, TK_REPEAT,
+  TK_RETURN, TK_THEN, TK_TRUE, TK_UNTIL, TK_WHILE,
+  /* other terminal symbols */
+  TK_IDIV, TK_CONCAT, TK_DOTS, TK_EQ, TK_GE, TK_LE, TK_NE,
+  TK_SHL, TK_SHR,
+  TK_DBCOLON, TK_EOS,
+  TK_FLT, TK_INT, TK_NAME, TK_STRING
+};
+
+/* number of reserved words */
+#define NUM_RESERVED	(cast_int(TK_WHILE-FIRST_RESERVED + 1))
+
+
+typedef union {
+  lua_Number r;
+  lua_Integer i;
+  TString *ts;
+} SemInfo;  /* semantics information */
+
+
+typedef struct Token {
+  int token;
+  SemInfo seminfo;
+} Token;
+
+
+/* state of the lexer plus state of the parser when shared by all
+   functions */
+typedef struct LexState {
+  int current;  /* current character (charint) */
+  int linenumber;  /* input line counter */
+  int lastline;  /* line of last token 'consumed' */
+  Token t;  /* current token */
+  Token lookahead;  /* look ahead token */
+  struct FuncState *fs;  /* current function (parser) */
+  struct lua_State *L;
+  ZIO *z;  /* input stream */
+  Mbuffer *buff;  /* buffer for tokens */
+  Table *h;  /* to avoid collection/reuse strings */
+  struct Dyndata *dyd;  /* dynamic structures used by the parser */
+  TString *source;  /* current source name */
+  TString *envn;  /* environment variable name */
+} LexState;
+
+
+LUAI_FUNC void luaX_init (lua_State *L);
+LUAI_FUNC void luaX_setinput (lua_State *L, LexState *ls, ZIO *z,
+                              TString *source, int firstchar);
+LUAI_FUNC TString *luaX_newstring (LexState *ls, const char *str, size_t l);
+LUAI_FUNC void luaX_next (LexState *ls);
+LUAI_FUNC int luaX_lookahead (LexState *ls);
+LUAI_FUNC l_noret luaX_syntaxerror (LexState *ls, const char *s);
+LUAI_FUNC const char *luaX_token2str (LexState *ls, int token);
+
+
+#endif
diff --git a/test/external/lua-5.4.0/src/llimits.h b/test/external/lua-5.4.0/src/llimits.h
new file mode 100644
index 0000000..b86d345
--- /dev/null
+++ b/test/external/lua-5.4.0/src/llimits.h
@@ -0,0 +1,349 @@
+/*
+** $Id: llimits.h $
+** Limits, basic types, and some other 'installation-dependent' definitions
+** See Copyright Notice in lua.h
+*/
+
+#ifndef llimits_h
+#define llimits_h
+
+
+#include <limits.h>
+#include <stddef.h>
+
+
+#include "lua.h"
+
+
+/*
+** 'lu_mem' and 'l_mem' are unsigned/signed integers big enough to count
+** the total memory used by Lua (in bytes). Usually, 'size_t' and
+** 'ptrdiff_t' should work, but we use 'long' for 16-bit machines.
+*/
+#if defined(LUAI_MEM)		/* { external definitions? */
+typedef LUAI_UMEM lu_mem;
+typedef LUAI_MEM l_mem;
+#elif LUAI_IS32INT	/* }{ */
+typedef size_t lu_mem;
+typedef ptrdiff_t l_mem;
+#else  /* 16-bit ints */	/* }{ */
+typedef unsigned long lu_mem;
+typedef long l_mem;
+#endif				/* } */
+
+
+/* chars used as small naturals (so that 'char' is reserved for characters) */
+typedef unsigned char lu_byte;
+typedef signed char ls_byte;
+
+
+/* maximum value for size_t */
+#define MAX_SIZET	((size_t)(~(size_t)0))
+
+/* maximum size visible for Lua (must be representable in a lua_Integer) */
+#define MAX_SIZE	(sizeof(size_t) < sizeof(lua_Integer) ? MAX_SIZET \
+                          : (size_t)(LUA_MAXINTEGER))
+
+
+#define MAX_LUMEM	((lu_mem)(~(lu_mem)0))
+
+#define MAX_LMEM	((l_mem)(MAX_LUMEM >> 1))
+
+
+#define MAX_INT		INT_MAX  /* maximum value of an int */
+
+
+/*
+** floor of the log2 of the maximum signed value for integral type 't'.
+** (That is, maximum 'n' such that '2^n' fits in the given signed type.)
+*/
+#define log2maxs(t)	(sizeof(t) * 8 - 2)
+
+
+/*
+** test whether an unsigned value is a power of 2 (or zero)
+*/
+#define ispow2(x)	(((x) & ((x) - 1)) == 0)
+
+
+/* number of chars of a literal string without the ending \0 */
+#define LL(x)   (sizeof(x)/sizeof(char) - 1)
+
+
+/*
+** conversion of pointer to unsigned integer:
+** this is for hashing only; there is no problem if the integer
+** cannot hold the whole pointer value
+*/
+#define point2uint(p)	((unsigned int)((size_t)(p) & UINT_MAX))
+
+
+
+/* types of 'usual argument conversions' for lua_Number and lua_Integer */
+typedef LUAI_UACNUMBER l_uacNumber;
+typedef LUAI_UACINT l_uacInt;
+
+
+/* internal assertions for in-house debugging */
+#if defined(lua_assert)
+#define check_exp(c,e)		(lua_assert(c), (e))
+/* to avoid problems with conditions too long */
+#define lua_longassert(c)	((c) ? (void)0 : lua_assert(0))
+#else
+#define lua_assert(c)		((void)0)
+#define check_exp(c,e)		(e)
+#define lua_longassert(c)	((void)0)
+#endif
+
+/*
+** assertion for checking API calls
+*/
+#if !defined(luai_apicheck)
+#define luai_apicheck(l,e)	((void)l, lua_assert(e))
+#endif
+
+#define api_check(l,e,msg)	luai_apicheck(l,(e) && msg)
+
+
+/* macro to avoid warnings about unused variables */
+#if !defined(UNUSED)
+#define UNUSED(x)	((void)(x))
+#endif
+
+
+/* type casts (a macro highlights casts in the code) */
+#define cast(t, exp)	((t)(exp))
+
+#define cast_void(i)	cast(void, (i))
+#define cast_voidp(i)	cast(void *, (i))
+#define cast_num(i)	cast(lua_Number, (i))
+#define cast_int(i)	cast(int, (i))
+#define cast_uint(i)	cast(unsigned int, (i))
+#define cast_byte(i)	cast(lu_byte, (i))
+#define cast_uchar(i)	cast(unsigned char, (i))
+#define cast_char(i)	cast(char, (i))
+#define cast_charp(i)	cast(char *, (i))
+#define cast_sizet(i)	cast(size_t, (i))
+
+
+/* cast a signed lua_Integer to lua_Unsigned */
+#if !defined(l_castS2U)
+#define l_castS2U(i)	((lua_Unsigned)(i))
+#endif
+
+/*
+** cast a lua_Unsigned to a signed lua_Integer; this cast is
+** not strict ISO C, but two-complement architectures should
+** work fine.
+*/
+#if !defined(l_castU2S)
+#define l_castU2S(i)	((lua_Integer)(i))
+#endif
+
+
+/*
+** macros to improve jump prediction (used mainly for error handling)
+*/
+#if !defined(likely)
+
+#if defined(__GNUC__)
+#define likely(x)	(__builtin_expect(((x) != 0), 1))
+#define unlikely(x)	(__builtin_expect(((x) != 0), 0))
+#else
+#define likely(x)	(x)
+#define unlikely(x)	(x)
+#endif
+
+#endif
+
+
+/*
+** non-return type
+*/
+#if !defined(l_noret)
+
+#if defined(__GNUC__)
+#define l_noret		void __attribute__((noreturn))
+#elif defined(_MSC_VER) && _MSC_VER >= 1200
+#define l_noret		void __declspec(noreturn)
+#else
+#define l_noret		void
+#endif
+
+#endif
+
+
+/*
+** type for virtual-machine instructions;
+** must be an unsigned with (at least) 4 bytes (see details in lopcodes.h)
+*/
+#if LUAI_IS32INT
+typedef unsigned int l_uint32;
+#else
+typedef unsigned long l_uint32;
+#endif
+
+typedef l_uint32 Instruction;
+
+
+
+/*
+** Maximum length for short strings, that is, strings that are
+** internalized. (Cannot be smaller than reserved words or tags for
+** metamethods, as these strings must be internalized;
+** #("function") = 8, #("__newindex") = 10.)
+*/
+#if !defined(LUAI_MAXSHORTLEN)
+#define LUAI_MAXSHORTLEN	40
+#endif
+
+
+/*
+** Initial size for the string table (must be power of 2).
+** The Lua core alone registers ~50 strings (reserved words +
+** metaevent keys + a few others). Libraries would typically add
+** a few dozens more.
+*/
+#if !defined(MINSTRTABSIZE)
+#define MINSTRTABSIZE	128
+#endif
+
+
+/*
+** Size of cache for strings in the API. 'N' is the number of
+** sets (better be a prime) and "M" is the size of each set (M == 1
+** makes a direct cache.)
+*/
+#if !defined(STRCACHE_N)
+#define STRCACHE_N		53
+#define STRCACHE_M		2
+#endif
+
+
+/* minimum size for string buffer */
+#if !defined(LUA_MINBUFFER)
+#define LUA_MINBUFFER	32
+#endif
+
+
+/*
+** macros that are executed whenever program enters the Lua core
+** ('lua_lock') and leaves the core ('lua_unlock')
+*/
+#if !defined(lua_lock)
+#define lua_lock(L)	((void) 0)
+#define lua_unlock(L)	((void) 0)
+#endif
+
+/*
+** macro executed during Lua functions at points where the
+** function can yield.
+*/
+#if !defined(luai_threadyield)
+#define luai_threadyield(L)	{lua_unlock(L); lua_lock(L);}
+#endif
+
+
+/*
+** these macros allow user-specific actions when a thread is
+** created/deleted/resumed/yielded.
+*/
+#if !defined(luai_userstateopen)
+#define luai_userstateopen(L)		((void)L)
+#endif
+
+#if !defined(luai_userstateclose)
+#define luai_userstateclose(L)		((void)L)
+#endif
+
+#if !defined(luai_userstatethread)
+#define luai_userstatethread(L,L1)	((void)L)
+#endif
+
+#if !defined(luai_userstatefree)
+#define luai_userstatefree(L,L1)	((void)L)
+#endif
+
+#if !defined(luai_userstateresume)
+#define luai_userstateresume(L,n)	((void)L)
+#endif
+
+#if !defined(luai_userstateyield)
+#define luai_userstateyield(L,n)	((void)L)
+#endif
+
+
+
+/*
+** The luai_num* macros define the primitive operations over numbers.
+*/
+
+/* floor division (defined as 'floor(a/b)') */
+#if !defined(luai_numidiv)
+#define luai_numidiv(L,a,b)     ((void)L, l_floor(luai_numdiv(L,a,b)))
+#endif
+
+/* float division */
+#if !defined(luai_numdiv)
+#define luai_numdiv(L,a,b)      ((a)/(b))
+#endif
+
+/*
+** modulo: defined as 'a - floor(a/b)*b'; the direct computation
+** using this definition has several problems with rounding errors,
+** so it is better to use 'fmod'. 'fmod' gives the result of
+** 'a - trunc(a/b)*b', and therefore must be corrected when
+** 'trunc(a/b) ~= floor(a/b)'. That happens when the division has a
+** non-integer negative result: non-integer result is equivalent to
+** a non-zero remainder 'm'; negative result is equivalent to 'a' and
+** 'b' with different signs, or 'm' and 'b' with different signs
+** (as the result 'm' of 'fmod' has the same sign of 'a').
+*/
+#if !defined(luai_nummod)
+#define luai_nummod(L,a,b,m)  \
+  { (void)L; (m) = l_mathop(fmod)(a,b); \
+    if (((m) > 0) ? (b) < 0 : ((m) < 0 && (b) > 0)) (m) += (b); }
+#endif
+
+/* exponentiation */
+#if !defined(luai_numpow)
+#define luai_numpow(L,a,b)      ((void)L, l_mathop(pow)(a,b))
+#endif
+
+/* the others are quite standard operations */
+#if !defined(luai_numadd)
+#define luai_numadd(L,a,b)      ((a)+(b))
+#define luai_numsub(L,a,b)      ((a)-(b))
+#define luai_nummul(L,a,b)      ((a)*(b))
+#define luai_numunm(L,a)        (-(a))
+#define luai_numeq(a,b)         ((a)==(b))
+#define luai_numlt(a,b)         ((a)<(b))
+#define luai_numle(a,b)         ((a)<=(b))
+#define luai_numgt(a,b)         ((a)>(b))
+#define luai_numge(a,b)         ((a)>=(b))
+#define luai_numisnan(a)        (!luai_numeq((a), (a)))
+#endif
+
+
+
+
+
+/*
+** macro to control inclusion of some hard tests on stack reallocation
+*/
+#if !defined(HARDSTACKTESTS)
+#define condmovestack(L,pre,pos)	((void)0)
+#else
+/* realloc stack keeping its size */
+#define condmovestack(L,pre,pos)  \
+  { int sz_ = (L)->stacksize; pre; luaD_reallocstack((L), sz_, 0); pos; }
+#endif
+
+#if !defined(HARDMEMTESTS)
+#define condchangemem(L,pre,pos)	((void)0)
+#else
+#define condchangemem(L,pre,pos)  \
+	{ if (G(L)->gcrunning) { pre; luaC_fullgc(L, 0); pos; } }
+#endif
+
+#endif
diff --git a/test/external/lua-5.4.0/src/lmathlib.c b/test/external/lua-5.4.0/src/lmathlib.c
new file mode 100644
index 0000000..86def47
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lmathlib.c
@@ -0,0 +1,763 @@
+/*
+** $Id: lmathlib.c $
+** Standard mathematical library
+** See Copyright Notice in lua.h
+*/
+
+#define lmathlib_c
+#define LUA_LIB
+
+#include "lprefix.h"
+
+
+#include <float.h>
+#include <limits.h>
+#include <math.h>
+#include <stdlib.h>
+#include <time.h>
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+#undef PI
+#define PI	(l_mathop(3.141592653589793238462643383279502884))
+
+
+static int math_abs (lua_State *L) {
+  if (lua_isinteger(L, 1)) {
+    lua_Integer n = lua_tointeger(L, 1);
+    if (n < 0) n = (lua_Integer)(0u - (lua_Unsigned)n);
+    lua_pushinteger(L, n);
+  }
+  else
+    lua_pushnumber(L, l_mathop(fabs)(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_sin (lua_State *L) {
+  lua_pushnumber(L, l_mathop(sin)(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_cos (lua_State *L) {
+  lua_pushnumber(L, l_mathop(cos)(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_tan (lua_State *L) {
+  lua_pushnumber(L, l_mathop(tan)(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_asin (lua_State *L) {
+  lua_pushnumber(L, l_mathop(asin)(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_acos (lua_State *L) {
+  lua_pushnumber(L, l_mathop(acos)(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_atan (lua_State *L) {
+  lua_Number y = luaL_checknumber(L, 1);
+  lua_Number x = luaL_optnumber(L, 2, 1);
+  lua_pushnumber(L, l_mathop(atan2)(y, x));
+  return 1;
+}
+
+
+static int math_toint (lua_State *L) {
+  int valid;
+  lua_Integer n = lua_tointegerx(L, 1, &valid);
+  if (valid)
+    lua_pushinteger(L, n);
+  else {
+    luaL_checkany(L, 1);
+    luaL_pushfail(L);  /* value is not convertible to integer */
+  }
+  return 1;
+}
+
+
+static void pushnumint (lua_State *L, lua_Number d) {
+  lua_Integer n;
+  if (lua_numbertointeger(d, &n))  /* does 'd' fit in an integer? */
+    lua_pushinteger(L, n);  /* result is integer */
+  else
+    lua_pushnumber(L, d);  /* result is float */
+}
+
+
+static int math_floor (lua_State *L) {
+  if (lua_isinteger(L, 1))
+    lua_settop(L, 1);  /* integer is its own floor */
+  else {
+    lua_Number d = l_mathop(floor)(luaL_checknumber(L, 1));
+    pushnumint(L, d);
+  }
+  return 1;
+}
+
+
+static int math_ceil (lua_State *L) {
+  if (lua_isinteger(L, 1))
+    lua_settop(L, 1);  /* integer is its own ceil */
+  else {
+    lua_Number d = l_mathop(ceil)(luaL_checknumber(L, 1));
+    pushnumint(L, d);
+  }
+  return 1;
+}
+
+
+static int math_fmod (lua_State *L) {
+  if (lua_isinteger(L, 1) && lua_isinteger(L, 2)) {
+    lua_Integer d = lua_tointeger(L, 2);
+    if ((lua_Unsigned)d + 1u <= 1u) {  /* special cases: -1 or 0 */
+      luaL_argcheck(L, d != 0, 2, "zero");
+      lua_pushinteger(L, 0);  /* avoid overflow with 0x80000... / -1 */
+    }
+    else
+      lua_pushinteger(L, lua_tointeger(L, 1) % d);
+  }
+  else
+    lua_pushnumber(L, l_mathop(fmod)(luaL_checknumber(L, 1),
+                                     luaL_checknumber(L, 2)));
+  return 1;
+}
+
+
+/*
+** next function does not use 'modf', avoiding problems with 'double*'
+** (which is not compatible with 'float*') when lua_Number is not
+** 'double'.
+*/
+static int math_modf (lua_State *L) {
+  if (lua_isinteger(L ,1)) {
+    lua_settop(L, 1);  /* number is its own integer part */
+    lua_pushnumber(L, 0);  /* no fractional part */
+  }
+  else {
+    lua_Number n = luaL_checknumber(L, 1);
+    /* integer part (rounds toward zero) */
+    lua_Number ip = (n < 0) ? l_mathop(ceil)(n) : l_mathop(floor)(n);
+    pushnumint(L, ip);
+    /* fractional part (test needed for inf/-inf) */
+    lua_pushnumber(L, (n == ip) ? l_mathop(0.0) : (n - ip));
+  }
+  return 2;
+}
+
+
+static int math_sqrt (lua_State *L) {
+  lua_pushnumber(L, l_mathop(sqrt)(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+
+static int math_ult (lua_State *L) {
+  lua_Integer a = luaL_checkinteger(L, 1);
+  lua_Integer b = luaL_checkinteger(L, 2);
+  lua_pushboolean(L, (lua_Unsigned)a < (lua_Unsigned)b);
+  return 1;
+}
+
+static int math_log (lua_State *L) {
+  lua_Number x = luaL_checknumber(L, 1);
+  lua_Number res;
+  if (lua_isnoneornil(L, 2))
+    res = l_mathop(log)(x);
+  else {
+    lua_Number base = luaL_checknumber(L, 2);
+#if !defined(LUA_USE_C89)
+    if (base == l_mathop(2.0))
+      res = l_mathop(log2)(x); else
+#endif
+    if (base == l_mathop(10.0))
+      res = l_mathop(log10)(x);
+    else
+      res = l_mathop(log)(x)/l_mathop(log)(base);
+  }
+  lua_pushnumber(L, res);
+  return 1;
+}
+
+static int math_exp (lua_State *L) {
+  lua_pushnumber(L, l_mathop(exp)(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_deg (lua_State *L) {
+  lua_pushnumber(L, luaL_checknumber(L, 1) * (l_mathop(180.0) / PI));
+  return 1;
+}
+
+static int math_rad (lua_State *L) {
+  lua_pushnumber(L, luaL_checknumber(L, 1) * (PI / l_mathop(180.0)));
+  return 1;
+}
+
+
+static int math_min (lua_State *L) {
+  int n = lua_gettop(L);  /* number of arguments */
+  int imin = 1;  /* index of current minimum value */
+  int i;
+  luaL_argcheck(L, n >= 1, 1, "value expected");
+  for (i = 2; i <= n; i++) {
+    if (lua_compare(L, i, imin, LUA_OPLT))
+      imin = i;
+  }
+  lua_pushvalue(L, imin);
+  return 1;
+}
+
+
+static int math_max (lua_State *L) {
+  int n = lua_gettop(L);  /* number of arguments */
+  int imax = 1;  /* index of current maximum value */
+  int i;
+  luaL_argcheck(L, n >= 1, 1, "value expected");
+  for (i = 2; i <= n; i++) {
+    if (lua_compare(L, imax, i, LUA_OPLT))
+      imax = i;
+  }
+  lua_pushvalue(L, imax);
+  return 1;
+}
+
+
+static int math_type (lua_State *L) {
+  if (lua_type(L, 1) == LUA_TNUMBER)
+    lua_pushstring(L, (lua_isinteger(L, 1)) ? "integer" : "float");
+  else {
+    luaL_checkany(L, 1);
+    luaL_pushfail(L);
+  }
+  return 1;
+}
+
+
+
+/*
+** {==================================================================
+** Pseudo-Random Number Generator based on 'xoshiro256**'.
+** ===================================================================
+*/
+
+/* number of binary digits in the mantissa of a float */
+#define FIGS	l_floatatt(MANT_DIG)
+
+#if FIGS > 64
+/* there are only 64 random bits; use them all */
+#undef FIGS
+#define FIGS	64
+#endif
+
+
+/*
+** LUA_RAND32 forces the use of 32-bit integers in the implementation
+** of the PRN generator (mainly for testing).
+*/
+#if !defined(LUA_RAND32) && !defined(Rand64)
+
+/* try to find an integer type with at least 64 bits */
+
+#if (ULONG_MAX >> 31 >> 31) >= 3
+
+/* 'long' has at least 64 bits */
+#define Rand64		unsigned long
+
+#elif !defined(LUA_USE_C89) && defined(LLONG_MAX)
+
+/* there is a 'long long' type (which must have at least 64 bits) */
+#define Rand64		unsigned long long
+
+#elif (LUA_MAXUNSIGNED >> 31 >> 31) >= 3
+
+/* 'lua_Integer' has at least 64 bits */
+#define Rand64		lua_Unsigned
+
+#endif
+
+#endif
+
+
+#if defined(Rand64)  /* { */
+
+/*
+** Standard implementation, using 64-bit integers.
+** If 'Rand64' has more than 64 bits, the extra bits do not interfere
+** with the 64 initial bits, except in a right shift. Moreover, the
+** final result has to discard the extra bits.
+*/
+
+/* avoid using extra bits when needed */
+#define trim64(x)	((x) & 0xffffffffffffffffu)
+
+
+/* rotate left 'x' by 'n' bits */
+static Rand64 rotl (Rand64 x, int n) {
+  return (x << n) | (trim64(x) >> (64 - n));
+}
+
+static Rand64 nextrand (Rand64 *state) {
+  Rand64 state0 = state[0];
+  Rand64 state1 = state[1];
+  Rand64 state2 = state[2] ^ state0;
+  Rand64 state3 = state[3] ^ state1;
+  Rand64 res = rotl(state1 * 5, 7) * 9;
+  state[0] = state0 ^ state3;
+  state[1] = state1 ^ state2;
+  state[2] = state2 ^ (state1 << 17);
+  state[3] = rotl(state3, 45);
+  return res;
+}
+
+
+/* must take care to not shift stuff by more than 63 slots */
+
+
+/*
+** Convert bits from a random integer into a float in the
+** interval [0,1), getting the higher FIG bits from the
+** random unsigned integer and converting that to a float.
+*/
+
+/* must throw out the extra (64 - FIGS) bits */
+#define shift64_FIG	(64 - FIGS)
+
+/* to scale to [0, 1), multiply by scaleFIG = 2^(-FIGS) */
+#define scaleFIG	(l_mathop(0.5) / ((Rand64)1 << (FIGS - 1)))
+
+static lua_Number I2d (Rand64 x) {
+  return (lua_Number)(trim64(x) >> shift64_FIG) * scaleFIG;
+}
+
+/* convert a 'Rand64' to a 'lua_Unsigned' */
+#define I2UInt(x)	((lua_Unsigned)trim64(x))
+
+/* convert a 'lua_Unsigned' to a 'Rand64' */
+#define Int2I(x)	((Rand64)(x))
+
+
+#else	/* no 'Rand64'   }{ */
+
+/* get an integer with at least 32 bits */
+#if LUAI_IS32INT
+typedef unsigned int lu_int32;
+#else
+typedef unsigned long lu_int32;
+#endif
+
+
+/*
+** Use two 32-bit integers to represent a 64-bit quantity.
+*/
+typedef struct Rand64 {
+  lu_int32 h;  /* higher half */
+  lu_int32 l;  /* lower half */
+} Rand64;
+
+
+/*
+** If 'lu_int32' has more than 32 bits, the extra bits do not interfere
+** with the 32 initial bits, except in a right shift and comparisons.
+** Moreover, the final result has to discard the extra bits.
+*/
+
+/* avoid using extra bits when needed */
+#define trim32(x)	((x) & 0xffffffffu)
+
+
+/*
+** basic operations on 'Rand64' values
+*/
+
+/* build a new Rand64 value */
+static Rand64 packI (lu_int32 h, lu_int32 l) {
+  Rand64 result;
+  result.h = h;
+  result.l = l;
+  return result;
+}
+
+/* return i << n */
+static Rand64 Ishl (Rand64 i, int n) {
+  lua_assert(n > 0 && n < 32);
+  return packI((i.h << n) | (trim32(i.l) >> (32 - n)), i.l << n);
+}
+
+/* i1 ^= i2 */
+static void Ixor (Rand64 *i1, Rand64 i2) {
+  i1->h ^= i2.h;
+  i1->l ^= i2.l;
+}
+
+/* return i1 + i2 */
+static Rand64 Iadd (Rand64 i1, Rand64 i2) {
+  Rand64 result = packI(i1.h + i2.h, i1.l + i2.l);
+  if (trim32(result.l) < trim32(i1.l))  /* carry? */
+    result.h++;
+  return result;
+}
+
+/* return i * 5 */
+static Rand64 times5 (Rand64 i) {
+  return Iadd(Ishl(i, 2), i);  /* i * 5 == (i << 2) + i */
+}
+
+/* return i * 9 */
+static Rand64 times9 (Rand64 i) {
+  return Iadd(Ishl(i, 3), i);  /* i * 9 == (i << 3) + i */
+}
+
+/* return 'i' rotated left 'n' bits */
+static Rand64 rotl (Rand64 i, int n) {
+  lua_assert(n > 0 && n < 32);
+  return packI((i.h << n) | (trim32(i.l) >> (32 - n)),
+               (trim32(i.h) >> (32 - n)) | (i.l << n));
+}
+
+/* for offsets larger than 32, rotate right by 64 - offset */
+static Rand64 rotl1 (Rand64 i, int n) {
+  lua_assert(n > 32 && n < 64);
+  n = 64 - n;
+  return packI((trim32(i.h) >> n) | (i.l << (32 - n)),
+               (i.h << (32 - n)) | (trim32(i.l) >> n));
+}
+
+/*
+** implementation of 'xoshiro256**' algorithm on 'Rand64' values
+*/
+static Rand64 nextrand (Rand64 *state) {
+  Rand64 res = times9(rotl(times5(state[1]), 7));
+  Rand64 t = Ishl(state[1], 17);
+  Ixor(&state[2], state[0]);
+  Ixor(&state[3], state[1]);
+  Ixor(&state[1], state[2]);
+  Ixor(&state[0], state[3]);
+  Ixor(&state[2], t);
+  state[3] = rotl1(state[3], 45);
+  return res;
+}
+
+
+/*
+** Converts a 'Rand64' into a float.
+*/
+
+/* an unsigned 1 with proper type */
+#define UONE		((lu_int32)1)
+
+
+#if FIGS <= 32
+
+/* 2^(-FIGS) */
+#define scaleFIG       (l_mathop(0.5) / (UONE << (FIGS - 1)))
+
+/*
+** get up to 32 bits from higher half, shifting right to
+** throw out the extra bits.
+*/
+static lua_Number I2d (Rand64 x) {
+  lua_Number h = (lua_Number)(trim32(x.h) >> (32 - FIGS));
+  return h * scaleFIG;
+}
+
+#else	/* 32 < FIGS <= 64 */
+
+/* must take care to not shift stuff by more than 31 slots */
+
+/* 2^(-FIGS) = 1.0 / 2^30 / 2^3 / 2^(FIGS-33) */
+#define scaleFIG  \
+	((lua_Number)1.0 / (UONE << 30) / 8.0 / (UONE << (FIGS - 33)))
+
+/*
+** use FIGS - 32 bits from lower half, throwing out the other
+** (32 - (FIGS - 32)) = (64 - FIGS) bits
+*/
+#define shiftLOW	(64 - FIGS)
+
+/*
+** higher 32 bits go after those (FIGS - 32) bits: shiftHI = 2^(FIGS - 32)
+*/
+#define shiftHI		((lua_Number)(UONE << (FIGS - 33)) * 2.0)
+
+
+static lua_Number I2d (Rand64 x) {
+  lua_Number h = (lua_Number)trim32(x.h) * shiftHI;
+  lua_Number l = (lua_Number)(trim32(x.l) >> shiftLOW);
+  return (h + l) * scaleFIG;
+}
+
+#endif
+
+
+/* convert a 'Rand64' to a 'lua_Unsigned' */
+static lua_Unsigned I2UInt (Rand64 x) {
+  return ((lua_Unsigned)trim32(x.h) << 31 << 1) | (lua_Unsigned)trim32(x.l);
+}
+
+/* convert a 'lua_Unsigned' to a 'Rand64' */
+static Rand64 Int2I (lua_Unsigned n) {
+  return packI((lu_int32)(n >> 31 >> 1), (lu_int32)n);
+}
+
+#endif  /* } */
+
+
+/*
+** A state uses four 'Rand64' values.
+*/
+typedef struct {
+  Rand64 s[4];
+} RanState;
+
+
+/*
+** Project the random integer 'ran' into the interval [0, n].
+** Because 'ran' has 2^B possible values, the projection can only be
+** uniform when the size of the interval is a power of 2 (exact
+** division). Otherwise, to get a uniform projection into [0, n], we
+** first compute 'lim', the smallest Mersenne number not smaller than
+** 'n'. We then project 'ran' into the interval [0, lim].  If the result
+** is inside [0, n], we are done. Otherwise, we try with another 'ran',
+** until we have a result inside the interval.
+*/
+static lua_Unsigned project (lua_Unsigned ran, lua_Unsigned n,
+                             RanState *state) {
+  if ((n & (n + 1)) == 0)  /* is 'n + 1' a power of 2? */
+    return ran & n;  /* no bias */
+  else {
+    lua_Unsigned lim = n;
+    /* compute the smallest (2^b - 1) not smaller than 'n' */
+    lim |= (lim >> 1);
+    lim |= (lim >> 2);
+    lim |= (lim >> 4);
+    lim |= (lim >> 8);
+    lim |= (lim >> 16);
+#if (LUA_MAXUNSIGNED >> 31) >= 3
+    lim |= (lim >> 32);  /* integer type has more than 32 bits */
+#endif
+    lua_assert((lim & (lim + 1)) == 0  /* 'lim + 1' is a power of 2, */
+      && lim >= n  /* not smaller than 'n', */
+      && (lim >> 1) < n);  /* and it is the smallest one */
+    while ((ran &= lim) > n)  /* project 'ran' into [0..lim] */
+      ran = I2UInt(nextrand(state->s));  /* not inside [0..n]? try again */
+    return ran;
+  }
+}
+
+
+static int math_random (lua_State *L) {
+  lua_Integer low, up;
+  lua_Unsigned p;
+  RanState *state = (RanState *)lua_touserdata(L, lua_upvalueindex(1));
+  Rand64 rv = nextrand(state->s);  /* next pseudo-random value */
+  switch (lua_gettop(L)) {  /* check number of arguments */
+    case 0: {  /* no arguments */
+      lua_pushnumber(L, I2d(rv));  /* float between 0 and 1 */
+      return 1;
+    }
+    case 1: {  /* only upper limit */
+      low = 1;
+      up = luaL_checkinteger(L, 1);
+      if (up == 0) {  /* single 0 as argument? */
+        lua_pushinteger(L, I2UInt(rv));  /* full random integer */
+        return 1;
+      }
+      break;
+    }
+    case 2: {  /* lower and upper limits */
+      low = luaL_checkinteger(L, 1);
+      up = luaL_checkinteger(L, 2);
+      break;
+    }
+    default: return luaL_error(L, "wrong number of arguments");
+  }
+  /* random integer in the interval [low, up] */
+  luaL_argcheck(L, low <= up, 1, "interval is empty");
+  /* project random integer into the interval [0, up - low] */
+  p = project(I2UInt(rv), (lua_Unsigned)up - (lua_Unsigned)low, state);
+  lua_pushinteger(L, p + (lua_Unsigned)low);
+  return 1;
+}
+
+
+static void setseed (lua_State *L, Rand64 *state,
+                     lua_Unsigned n1, lua_Unsigned n2) {
+  int i;
+  state[0] = Int2I(n1);
+  state[1] = Int2I(0xff);  /* avoid a zero state */
+  state[2] = Int2I(n2);
+  state[3] = Int2I(0);
+  for (i = 0; i < 16; i++)
+    nextrand(state);  /* discard initial values to "spread" seed */
+  lua_pushinteger(L, n1);
+  lua_pushinteger(L, n2);
+}
+
+
+/*
+** Set a "random" seed. To get some randomness, use the current time
+** and the address of 'L' (in case the machine does address space layout
+** randomization).
+*/
+static void randseed (lua_State *L, RanState *state) {
+  lua_Unsigned seed1 = (lua_Unsigned)time(NULL);
+  lua_Unsigned seed2 = (lua_Unsigned)(size_t)L;
+  setseed(L, state->s, seed1, seed2);
+}
+
+
+static int math_randomseed (lua_State *L) {
+  RanState *state = (RanState *)lua_touserdata(L, lua_upvalueindex(1));
+  if (lua_isnone(L, 1)) {
+    randseed(L, state);
+  }
+  else {
+    lua_Integer n1 = luaL_checkinteger(L, 1);
+    lua_Integer n2 = luaL_optinteger(L, 2, 0);
+    setseed(L, state->s, n1, n2);
+  }
+  return 2;  /* return seeds */
+}
+
+
+static const luaL_Reg randfuncs[] = {
+  {"random", math_random},
+  {"randomseed", math_randomseed},
+  {NULL, NULL}
+};
+
+
+/*
+** Register the random functions and initialize their state.
+*/
+static void setrandfunc (lua_State *L) {
+  RanState *state = (RanState *)lua_newuserdatauv(L, sizeof(RanState), 0);
+  randseed(L, state);  /* initialize with a "random" seed */
+  lua_pop(L, 2);  /* remove pushed seeds */
+  luaL_setfuncs(L, randfuncs, 1);
+}
+
+/* }================================================================== */
+
+
+/*
+** {==================================================================
+** Deprecated functions (for compatibility only)
+** ===================================================================
+*/
+#if defined(LUA_COMPAT_MATHLIB)
+
+static int math_cosh (lua_State *L) {
+  lua_pushnumber(L, l_mathop(cosh)(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_sinh (lua_State *L) {
+  lua_pushnumber(L, l_mathop(sinh)(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_tanh (lua_State *L) {
+  lua_pushnumber(L, l_mathop(tanh)(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_pow (lua_State *L) {
+  lua_Number x = luaL_checknumber(L, 1);
+  lua_Number y = luaL_checknumber(L, 2);
+  lua_pushnumber(L, l_mathop(pow)(x, y));
+  return 1;
+}
+
+static int math_frexp (lua_State *L) {
+  int e;
+  lua_pushnumber(L, l_mathop(frexp)(luaL_checknumber(L, 1), &e));
+  lua_pushinteger(L, e);
+  return 2;
+}
+
+static int math_ldexp (lua_State *L) {
+  lua_Number x = luaL_checknumber(L, 1);
+  int ep = (int)luaL_checkinteger(L, 2);
+  lua_pushnumber(L, l_mathop(ldexp)(x, ep));
+  return 1;
+}
+
+static int math_log10 (lua_State *L) {
+  lua_pushnumber(L, l_mathop(log10)(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+#endif
+/* }================================================================== */
+
+
+
+static const luaL_Reg mathlib[] = {
+  {"abs",   math_abs},
+  {"acos",  math_acos},
+  {"asin",  math_asin},
+  {"atan",  math_atan},
+  {"ceil",  math_ceil},
+  {"cos",   math_cos},
+  {"deg",   math_deg},
+  {"exp",   math_exp},
+  {"tointeger", math_toint},
+  {"floor", math_floor},
+  {"fmod",   math_fmod},
+  {"ult",   math_ult},
+  {"log",   math_log},
+  {"max",   math_max},
+  {"min",   math_min},
+  {"modf",   math_modf},
+  {"rad",   math_rad},
+  {"sin",   math_sin},
+  {"sqrt",  math_sqrt},
+  {"tan",   math_tan},
+  {"type", math_type},
+#if defined(LUA_COMPAT_MATHLIB)
+  {"atan2", math_atan},
+  {"cosh",   math_cosh},
+  {"sinh",   math_sinh},
+  {"tanh",   math_tanh},
+  {"pow",   math_pow},
+  {"frexp", math_frexp},
+  {"ldexp", math_ldexp},
+  {"log10", math_log10},
+#endif
+  /* placeholders */
+  {"random", NULL},
+  {"randomseed", NULL},
+  {"pi", NULL},
+  {"huge", NULL},
+  {"maxinteger", NULL},
+  {"mininteger", NULL},
+  {NULL, NULL}
+};
+
+
+/*
+** Open math library
+*/
+LUAMOD_API int luaopen_math (lua_State *L) {
+  luaL_newlib(L, mathlib);
+  lua_pushnumber(L, PI);
+  lua_setfield(L, -2, "pi");
+  lua_pushnumber(L, (lua_Number)HUGE_VAL);
+  lua_setfield(L, -2, "huge");
+  lua_pushinteger(L, LUA_MAXINTEGER);
+  lua_setfield(L, -2, "maxinteger");
+  lua_pushinteger(L, LUA_MININTEGER);
+  lua_setfield(L, -2, "mininteger");
+  setrandfunc(L);
+  return 1;
+}
+
diff --git a/test/external/lua-5.4.0/src/lmem.c b/test/external/lua-5.4.0/src/lmem.c
new file mode 100644
index 0000000..65bfa52
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lmem.c
@@ -0,0 +1,202 @@
+/*
+** $Id: lmem.c $
+** Interface to Memory Manager
+** See Copyright Notice in lua.h
+*/
+
+#define lmem_c
+#define LUA_CORE
+
+#include "lprefix.h"
+
+
+#include <stddef.h>
+
+#include "lua.h"
+
+#include "ldebug.h"
+#include "ldo.h"
+#include "lgc.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lstate.h"
+
+
+#if defined(HARDMEMTESTS)
+/*
+** First allocation will fail whenever not building initial state
+** and not shrinking a block. (This fail will trigger 'tryagain' and
+** a full GC cycle at every allocation.)
+*/
+static void *firsttry (global_State *g, void *block, size_t os, size_t ns) {
+  if (ttisnil(&g->nilvalue) && ns > os)
+    return NULL;  /* fail */
+  else  /* normal allocation */
+    return (*g->frealloc)(g->ud, block, os, ns);
+}
+#else
+#define firsttry(g,block,os,ns)    ((*g->frealloc)(g->ud, block, os, ns))
+#endif
+
+
+
+
+
+/*
+** About the realloc function:
+** void *frealloc (void *ud, void *ptr, size_t osize, size_t nsize);
+** ('osize' is the old size, 'nsize' is the new size)
+**
+** - frealloc(ud, p, x, 0) frees the block 'p' and returns NULL.
+** Particularly, frealloc(ud, NULL, 0, 0) does nothing,
+** which is equivalent to free(NULL) in ISO C.
+**
+** - frealloc(ud, NULL, x, s) creates a new block of size 's'
+** (no matter 'x'). Returns NULL if it cannot create the new block.
+**
+** - otherwise, frealloc(ud, b, x, y) reallocates the block 'b' from
+** size 'x' to size 'y'. Returns NULL if it cannot reallocate the
+** block to the new size.
+*/
+
+
+
+
+/*
+** {==================================================================
+** Functions to allocate/deallocate arrays for the Parser
+** ===================================================================
+*/
+
+/*
+** Minimum size for arrays during parsing, to avoid overhead of
+** reallocating to size 1, then 2, and then 4. All these arrays
+** will be reallocated to exact sizes or erased when parsing ends.
+*/
+#define MINSIZEARRAY	4
+
+
+void *luaM_growaux_ (lua_State *L, void *block, int nelems, int *psize,
+                     int size_elems, int limit, const char *what) {
+  void *newblock;
+  int size = *psize;
+  if (nelems + 1 <= size)  /* does one extra element still fit? */
+    return block;  /* nothing to be done */
+  if (size >= limit / 2) {  /* cannot double it? */
+    if (unlikely(size >= limit))  /* cannot grow even a little? */
+      luaG_runerror(L, "too many %s (limit is %d)", what, limit);
+    size = limit;  /* still have at least one free place */
+  }
+  else {
+    size *= 2;
+    if (size < MINSIZEARRAY)
+      size = MINSIZEARRAY;  /* minimum size */
+  }
+  lua_assert(nelems + 1 <= size && size <= limit);
+  /* 'limit' ensures that multiplication will not overflow */
+  newblock = luaM_saferealloc_(L, block, cast_sizet(*psize) * size_elems,
+                                         cast_sizet(size) * size_elems);
+  *psize = size;  /* update only when everything else is OK */
+  return newblock;
+}
+
+
+/*
+** In prototypes, the size of the array is also its number of
+** elements (to save memory). So, if it cannot shrink an array
+** to its number of elements, the only option is to raise an
+** error.
+*/
+void *luaM_shrinkvector_ (lua_State *L, void *block, int *size,
+                          int final_n, int size_elem) {
+  void *newblock;
+  size_t oldsize = cast_sizet((*size) * size_elem);
+  size_t newsize = cast_sizet(final_n * size_elem);
+  lua_assert(newsize <= oldsize);
+  newblock = luaM_saferealloc_(L, block, oldsize, newsize);
+  *size = final_n;
+  return newblock;
+}
+
+/* }================================================================== */
+
+
+l_noret luaM_toobig (lua_State *L) {
+  luaG_runerror(L, "memory allocation error: block too big");
+}
+
+
+/*
+** Free memory
+*/
+void luaM_free_ (lua_State *L, void *block, size_t osize) {
+  global_State *g = G(L);
+  lua_assert((osize == 0) == (block == NULL));
+  (*g->frealloc)(g->ud, block, osize, 0);
+  g->GCdebt -= osize;
+}
+
+
+/*
+** In case of allocation fail, this function will call the GC to try
+** to free some memory and then try the allocation again.
+** (It should not be called when shrinking a block, because then the
+** interpreter may be in the middle of a collection step.)
+*/
+static void *tryagain (lua_State *L, void *block,
+                       size_t osize, size_t nsize) {
+  global_State *g = G(L);
+  if (ttisnil(&g->nilvalue)) {  /* is state fully build? */
+    luaC_fullgc(L, 1);  /* try to free some memory... */
+    return (*g->frealloc)(g->ud, block, osize, nsize);  /* try again */
+  }
+  else return NULL;  /* cannot free any memory without a full state */
+}
+
+
+/*
+** Generic allocation routine.
+** If allocation fails while shrinking a block, do not try again; the
+** GC shrinks some blocks and it is not reentrant.
+*/
+void *luaM_realloc_ (lua_State *L, void *block, size_t osize, size_t nsize) {
+  void *newblock;
+  global_State *g = G(L);
+  lua_assert((osize == 0) == (block == NULL));
+  newblock = firsttry(g, block, osize, nsize);
+  if (unlikely(newblock == NULL && nsize > 0)) {
+    if (nsize > osize)  /* not shrinking a block? */
+      newblock = tryagain(L, block, osize, nsize);
+    if (newblock == NULL)  /* still no memory? */
+      return NULL;  /* do not update 'GCdebt' */
+  }
+  lua_assert((nsize == 0) == (newblock == NULL));
+  g->GCdebt = (g->GCdebt + nsize) - osize;
+  return newblock;
+}
+
+
+void *luaM_saferealloc_ (lua_State *L, void *block, size_t osize,
+                                                    size_t nsize) {
+  void *newblock = luaM_realloc_(L, block, osize, nsize);
+  if (unlikely(newblock == NULL && nsize > 0))  /* allocation failed? */
+    luaM_error(L);
+  return newblock;
+}
+
+
+void *luaM_malloc_ (lua_State *L, size_t size, int tag) {
+  if (size == 0)
+    return NULL;  /* that's all */
+  else {
+    global_State *g = G(L);
+    void *newblock = firsttry(g, NULL, tag, size);
+    if (unlikely(newblock == NULL)) {
+      newblock = tryagain(L, NULL, tag, size);
+      if (newblock == NULL)
+        luaM_error(L);
+    }
+    g->GCdebt += size;
+    return newblock;
+  }
+}
diff --git a/test/external/lua-5.4.0/src/lmem.h b/test/external/lua-5.4.0/src/lmem.h
new file mode 100644
index 0000000..8c75a44
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lmem.h
@@ -0,0 +1,93 @@
+/*
+** $Id: lmem.h $
+** Interface to Memory Manager
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lmem_h
+#define lmem_h
+
+
+#include <stddef.h>
+
+#include "llimits.h"
+#include "lua.h"
+
+
+#define luaM_error(L)	luaD_throw(L, LUA_ERRMEM)
+
+
+/*
+** This macro tests whether it is safe to multiply 'n' by the size of
+** type 't' without overflows. Because 'e' is always constant, it avoids
+** the runtime division MAX_SIZET/(e).
+** (The macro is somewhat complex to avoid warnings:  The 'sizeof'
+** comparison avoids a runtime comparison when overflow cannot occur.
+** The compiler should be able to optimize the real test by itself, but
+** when it does it, it may give a warning about "comparison is always
+** false due to limited range of data type"; the +1 tricks the compiler,
+** avoiding this warning but also this optimization.)
+*/
+#define luaM_testsize(n,e)  \
+	(sizeof(n) >= sizeof(size_t) && cast_sizet((n)) + 1 > MAX_SIZET/(e))
+
+#define luaM_checksize(L,n,e)  \
+	(luaM_testsize(n,e) ? luaM_toobig(L) : cast_void(0))
+
+
+/*
+** Computes the minimum between 'n' and 'MAX_SIZET/sizeof(t)', so that
+** the result is not larger than 'n' and cannot overflow a 'size_t'
+** when multiplied by the size of type 't'. (Assumes that 'n' is an
+** 'int' or 'unsigned int' and that 'int' is not larger than 'size_t'.)
+*/
+#define luaM_limitN(n,t)  \
+  ((cast_sizet(n) <= MAX_SIZET/sizeof(t)) ? (n) :  \
+     cast_uint((MAX_SIZET/sizeof(t))))
+
+
+/*
+** Arrays of chars do not need any test
+*/
+#define luaM_reallocvchar(L,b,on,n)  \
+  cast_charp(luaM_saferealloc_(L, (b), (on)*sizeof(char), (n)*sizeof(char)))
+
+#define luaM_freemem(L, b, s)	luaM_free_(L, (b), (s))
+#define luaM_free(L, b)		luaM_free_(L, (b), sizeof(*(b)))
+#define luaM_freearray(L, b, n)   luaM_free_(L, (b), (n)*sizeof(*(b)))
+
+#define luaM_new(L,t)		cast(t*, luaM_malloc_(L, sizeof(t), 0))
+#define luaM_newvector(L,n,t)	cast(t*, luaM_malloc_(L, (n)*sizeof(t), 0))
+#define luaM_newvectorchecked(L,n,t) \
+  (luaM_checksize(L,n,sizeof(t)), luaM_newvector(L,n,t))
+
+#define luaM_newobject(L,tag,s)	luaM_malloc_(L, (s), tag)
+
+#define luaM_growvector(L,v,nelems,size,t,limit,e) \
+	((v)=cast(t *, luaM_growaux_(L,v,nelems,&(size),sizeof(t), \
+                         luaM_limitN(limit,t),e)))
+
+#define luaM_reallocvector(L, v,oldn,n,t) \
+   (cast(t *, luaM_realloc_(L, v, cast_sizet(oldn) * sizeof(t), \
+                                  cast_sizet(n) * sizeof(t))))
+
+#define luaM_shrinkvector(L,v,size,fs,t) \
+   ((v)=cast(t *, luaM_shrinkvector_(L, v, &(size), fs, sizeof(t))))
+
+LUAI_FUNC l_noret luaM_toobig (lua_State *L);
+
+/* not to be called directly */
+LUAI_FUNC void *luaM_realloc_ (lua_State *L, void *block, size_t oldsize,
+                                                          size_t size);
+LUAI_FUNC void *luaM_saferealloc_ (lua_State *L, void *block, size_t oldsize,
+                                                              size_t size);
+LUAI_FUNC void luaM_free_ (lua_State *L, void *block, size_t osize);
+LUAI_FUNC void *luaM_growaux_ (lua_State *L, void *block, int nelems,
+                               int *size, int size_elem, int limit,
+                               const char *what);
+LUAI_FUNC void *luaM_shrinkvector_ (lua_State *L, void *block, int *nelem,
+                                    int final_n, int size_elem);
+LUAI_FUNC void *luaM_malloc_ (lua_State *L, size_t size, int tag);
+
+#endif
+
diff --git a/test/external/lua-5.4.0/src/loadlib.c b/test/external/lua-5.4.0/src/loadlib.c
new file mode 100644
index 0000000..c0ec9a1
--- /dev/null
+++ b/test/external/lua-5.4.0/src/loadlib.c
@@ -0,0 +1,759 @@
+/*
+** $Id: loadlib.c $
+** Dynamic library loader for Lua
+** See Copyright Notice in lua.h
+**
+** This module contains an implementation of loadlib for Unix systems
+** that have dlfcn, an implementation for Windows, and a stub for other
+** systems.
+*/
+
+#define loadlib_c
+#define LUA_LIB
+
+#include "lprefix.h"
+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+/*
+** LUA_IGMARK is a mark to ignore all before it when building the
+** luaopen_ function name.
+*/
+#if !defined (LUA_IGMARK)
+#define LUA_IGMARK		"-"
+#endif
+
+
+/*
+** LUA_CSUBSEP is the character that replaces dots in submodule names
+** when searching for a C loader.
+** LUA_LSUBSEP is the character that replaces dots in submodule names
+** when searching for a Lua loader.
+*/
+#if !defined(LUA_CSUBSEP)
+#define LUA_CSUBSEP		LUA_DIRSEP
+#endif
+
+#if !defined(LUA_LSUBSEP)
+#define LUA_LSUBSEP		LUA_DIRSEP
+#endif
+
+
+/* prefix for open functions in C libraries */
+#define LUA_POF		"luaopen_"
+
+/* separator for open functions in C libraries */
+#define LUA_OFSEP	"_"
+
+
+/*
+** key for table in the registry that keeps handles
+** for all loaded C libraries
+*/
+static const char *const CLIBS = "_CLIBS";
+
+#define LIB_FAIL	"open"
+
+
+#define setprogdir(L)           ((void)0)
+
+
+/*
+** Special type equivalent to '(void*)' for functions in gcc
+** (to suppress warnings when converting function pointers)
+*/
+typedef void (*voidf)(void);
+
+
+/*
+** system-dependent functions
+*/
+
+/*
+** unload library 'lib'
+*/
+static void lsys_unloadlib (void *lib);
+
+/*
+** load C library in file 'path'. If 'seeglb', load with all names in
+** the library global.
+** Returns the library; in case of error, returns NULL plus an
+** error string in the stack.
+*/
+static void *lsys_load (lua_State *L, const char *path, int seeglb);
+
+/*
+** Try to find a function named 'sym' in library 'lib'.
+** Returns the function; in case of error, returns NULL plus an
+** error string in the stack.
+*/
+static lua_CFunction lsys_sym (lua_State *L, void *lib, const char *sym);
+
+
+
+
+#if defined(LUA_USE_DLOPEN)	/* { */
+/*
+** {========================================================================
+** This is an implementation of loadlib based on the dlfcn interface.
+** The dlfcn interface is available in Linux, SunOS, Solaris, IRIX, FreeBSD,
+** NetBSD, AIX 4.2, HPUX 11, and  probably most other Unix flavors, at least
+** as an emulation layer on top of native functions.
+** =========================================================================
+*/
+
+#include <dlfcn.h>
+
+/*
+** Macro to convert pointer-to-void* to pointer-to-function. This cast
+** is undefined according to ISO C, but POSIX assumes that it works.
+** (The '__extension__' in gnu compilers is only to avoid warnings.)
+*/
+#if defined(__GNUC__)
+#define cast_func(p) (__extension__ (lua_CFunction)(p))
+#else
+#define cast_func(p) ((lua_CFunction)(p))
+#endif
+
+
+static void lsys_unloadlib (void *lib) {
+  dlclose(lib);
+}
+
+
+static void *lsys_load (lua_State *L, const char *path, int seeglb) {
+  void *lib = dlopen(path, RTLD_NOW | (seeglb ? RTLD_GLOBAL : RTLD_LOCAL));
+  if (lib == NULL) lua_pushstring(L, dlerror());
+  return lib;
+}
+
+
+static lua_CFunction lsys_sym (lua_State *L, void *lib, const char *sym) {
+  lua_CFunction f = cast_func(dlsym(lib, sym));
+  if (f == NULL) lua_pushstring(L, dlerror());
+  return f;
+}
+
+/* }====================================================== */
+
+
+
+#elif defined(LUA_DL_DLL)	/* }{ */
+/*
+** {======================================================================
+** This is an implementation of loadlib for Windows using native functions.
+** =======================================================================
+*/
+
+#include <windows.h>
+
+
+/*
+** optional flags for LoadLibraryEx
+*/
+#if !defined(LUA_LLE_FLAGS)
+#define LUA_LLE_FLAGS	0
+#endif
+
+
+#undef setprogdir
+
+
+/*
+** Replace in the path (on the top of the stack) any occurrence
+** of LUA_EXEC_DIR with the executable's path.
+*/
+static void setprogdir (lua_State *L) {
+  char buff[MAX_PATH + 1];
+  char *lb;
+  DWORD nsize = sizeof(buff)/sizeof(char);
+  DWORD n = GetModuleFileNameA(NULL, buff, nsize);  /* get exec. name */
+  if (n == 0 || n == nsize || (lb = strrchr(buff, '\\')) == NULL)
+    luaL_error(L, "unable to get ModuleFileName");
+  else {
+    *lb = '\0';  /* cut name on the last '\\' to get the path */
+    luaL_gsub(L, lua_tostring(L, -1), LUA_EXEC_DIR, buff);
+    lua_remove(L, -2);  /* remove original string */
+  }
+}
+
+
+
+
+static void pusherror (lua_State *L) {
+  int error = GetLastError();
+  char buffer[128];
+  if (FormatMessageA(FORMAT_MESSAGE_IGNORE_INSERTS | FORMAT_MESSAGE_FROM_SYSTEM,
+      NULL, error, 0, buffer, sizeof(buffer)/sizeof(char), NULL))
+    lua_pushstring(L, buffer);
+  else
+    lua_pushfstring(L, "system error %d\n", error);
+}
+
+static void lsys_unloadlib (void *lib) {
+  FreeLibrary((HMODULE)lib);
+}
+
+
+static void *lsys_load (lua_State *L, const char *path, int seeglb) {
+  HMODULE lib = LoadLibraryExA(path, NULL, LUA_LLE_FLAGS);
+  (void)(seeglb);  /* not used: symbols are 'global' by default */
+  if (lib == NULL) pusherror(L);
+  return lib;
+}
+
+
+static lua_CFunction lsys_sym (lua_State *L, void *lib, const char *sym) {
+  lua_CFunction f = (lua_CFunction)(voidf)GetProcAddress((HMODULE)lib, sym);
+  if (f == NULL) pusherror(L);
+  return f;
+}
+
+/* }====================================================== */
+
+
+#else				/* }{ */
+/*
+** {======================================================
+** Fallback for other systems
+** =======================================================
+*/
+
+#undef LIB_FAIL
+#define LIB_FAIL	"absent"
+
+
+#define DLMSG	"dynamic libraries not enabled; check your Lua installation"
+
+
+static void lsys_unloadlib (void *lib) {
+  (void)(lib);  /* not used */
+}
+
+
+static void *lsys_load (lua_State *L, const char *path, int seeglb) {
+  (void)(path); (void)(seeglb);  /* not used */
+  lua_pushliteral(L, DLMSG);
+  return NULL;
+}
+
+
+static lua_CFunction lsys_sym (lua_State *L, void *lib, const char *sym) {
+  (void)(lib); (void)(sym);  /* not used */
+  lua_pushliteral(L, DLMSG);
+  return NULL;
+}
+
+/* }====================================================== */
+#endif				/* } */
+
+
+/*
+** {==================================================================
+** Set Paths
+** ===================================================================
+*/
+
+/*
+** LUA_PATH_VAR and LUA_CPATH_VAR are the names of the environment
+** variables that Lua check to set its paths.
+*/
+#if !defined(LUA_PATH_VAR)
+#define LUA_PATH_VAR    "LUA_PATH"
+#endif
+
+#if !defined(LUA_CPATH_VAR)
+#define LUA_CPATH_VAR   "LUA_CPATH"
+#endif
+
+
+
+/*
+** return registry.LUA_NOENV as a boolean
+*/
+static int noenv (lua_State *L) {
+  int b;
+  lua_getfield(L, LUA_REGISTRYINDEX, "LUA_NOENV");
+  b = lua_toboolean(L, -1);
+  lua_pop(L, 1);  /* remove value */
+  return b;
+}
+
+
+/*
+** Set a path
+*/
+static void setpath (lua_State *L, const char *fieldname,
+                                   const char *envname,
+                                   const char *dft) {
+  const char *dftmark;
+  const char *nver = lua_pushfstring(L, "%s%s", envname, LUA_VERSUFFIX);
+  const char *path = getenv(nver);  /* try versioned name */
+  if (path == NULL)  /* no versioned environment variable? */
+    path = getenv(envname);  /* try unversioned name */
+  if (path == NULL || noenv(L))  /* no environment variable? */
+    lua_pushstring(L, dft);  /* use default */
+  else if ((dftmark = strstr(path, LUA_PATH_SEP LUA_PATH_SEP)) == NULL)
+    lua_pushstring(L, path);  /* nothing to change */
+  else {  /* path contains a ";;": insert default path in its place */
+    size_t len = strlen(path);
+    luaL_Buffer b;
+    luaL_buffinit(L, &b);
+    if (path < dftmark) {  /* is there a prefix before ';;'? */
+      luaL_addlstring(&b, path, dftmark - path);  /* add it */
+      luaL_addchar(&b, *LUA_PATH_SEP);
+    }
+    luaL_addstring(&b, dft);  /* add default */
+    if (dftmark < path + len - 2) {  /* is there a suffix after ';;'? */
+      luaL_addchar(&b, *LUA_PATH_SEP);
+      luaL_addlstring(&b, dftmark + 2, (path + len - 2) - dftmark);
+    }
+    luaL_pushresult(&b);
+  }
+  setprogdir(L);
+  lua_setfield(L, -3, fieldname);  /* package[fieldname] = path value */
+  lua_pop(L, 1);  /* pop versioned variable name ('nver') */
+}
+
+/* }================================================================== */
+
+
+/*
+** return registry.CLIBS[path]
+*/
+static void *checkclib (lua_State *L, const char *path) {
+  void *plib;
+  lua_getfield(L, LUA_REGISTRYINDEX, CLIBS);
+  lua_getfield(L, -1, path);
+  plib = lua_touserdata(L, -1);  /* plib = CLIBS[path] */
+  lua_pop(L, 2);  /* pop CLIBS table and 'plib' */
+  return plib;
+}
+
+
+/*
+** registry.CLIBS[path] = plib        -- for queries
+** registry.CLIBS[#CLIBS + 1] = plib  -- also keep a list of all libraries
+*/
+static void addtoclib (lua_State *L, const char *path, void *plib) {
+  lua_getfield(L, LUA_REGISTRYINDEX, CLIBS);
+  lua_pushlightuserdata(L, plib);
+  lua_pushvalue(L, -1);
+  lua_setfield(L, -3, path);  /* CLIBS[path] = plib */
+  lua_rawseti(L, -2, luaL_len(L, -2) + 1);  /* CLIBS[#CLIBS + 1] = plib */
+  lua_pop(L, 1);  /* pop CLIBS table */
+}
+
+
+/*
+** __gc tag method for CLIBS table: calls 'lsys_unloadlib' for all lib
+** handles in list CLIBS
+*/
+static int gctm (lua_State *L) {
+  lua_Integer n = luaL_len(L, 1);
+  for (; n >= 1; n--) {  /* for each handle, in reverse order */
+    lua_rawgeti(L, 1, n);  /* get handle CLIBS[n] */
+    lsys_unloadlib(lua_touserdata(L, -1));
+    lua_pop(L, 1);  /* pop handle */
+  }
+  return 0;
+}
+
+
+
+/* error codes for 'lookforfunc' */
+#define ERRLIB		1
+#define ERRFUNC		2
+
+/*
+** Look for a C function named 'sym' in a dynamically loaded library
+** 'path'.
+** First, check whether the library is already loaded; if not, try
+** to load it.
+** Then, if 'sym' is '*', return true (as library has been loaded).
+** Otherwise, look for symbol 'sym' in the library and push a
+** C function with that symbol.
+** Return 0 and 'true' or a function in the stack; in case of
+** errors, return an error code and an error message in the stack.
+*/
+static int lookforfunc (lua_State *L, const char *path, const char *sym) {
+  void *reg = checkclib(L, path);  /* check loaded C libraries */
+  if (reg == NULL) {  /* must load library? */
+    reg = lsys_load(L, path, *sym == '*');  /* global symbols if 'sym'=='*' */
+    if (reg == NULL) return ERRLIB;  /* unable to load library */
+    addtoclib(L, path, reg);
+  }
+  if (*sym == '*') {  /* loading only library (no function)? */
+    lua_pushboolean(L, 1);  /* return 'true' */
+    return 0;  /* no errors */
+  }
+  else {
+    lua_CFunction f = lsys_sym(L, reg, sym);
+    if (f == NULL)
+      return ERRFUNC;  /* unable to find function */
+    lua_pushcfunction(L, f);  /* else create new function */
+    return 0;  /* no errors */
+  }
+}
+
+
+static int ll_loadlib (lua_State *L) {
+  const char *path = luaL_checkstring(L, 1);
+  const char *init = luaL_checkstring(L, 2);
+  int stat = lookforfunc(L, path, init);
+  if (stat == 0)  /* no errors? */
+    return 1;  /* return the loaded function */
+  else {  /* error; error message is on stack top */
+    luaL_pushfail(L);
+    lua_insert(L, -2);
+    lua_pushstring(L, (stat == ERRLIB) ?  LIB_FAIL : "init");
+    return 3;  /* return fail, error message, and where */
+  }
+}
+
+
+
+/*
+** {======================================================
+** 'require' function
+** =======================================================
+*/
+
+
+static int readable (const char *filename) {
+  FILE *f = fopen(filename, "r");  /* try to open file */
+  if (f == NULL) return 0;  /* open failed */
+  fclose(f);
+  return 1;
+}
+
+
+/*
+** Get the next name in '*path' = 'name1;name2;name3;...', changing
+** the ending ';' to '\0' to create a zero-terminated string. Return
+** NULL when list ends.
+*/
+static const char *getnextfilename (char **path, char *end) {
+  char *sep;
+  char *name = *path;
+  if (name == end)
+    return NULL;  /* no more names */
+  else if (*name == '\0') {  /* from previous iteration? */
+    *name = *LUA_PATH_SEP;  /* restore separator */
+    name++;  /* skip it */
+  }
+  sep = strchr(name, *LUA_PATH_SEP);  /* find next separator */
+  if (sep == NULL)  /* separator not found? */
+    sep = end;  /* name goes until the end */
+  *sep = '\0';  /* finish file name */
+  *path = sep;  /* will start next search from here */
+  return name;
+}
+
+
+/*
+** Given a path such as ";blabla.so;blublu.so", pushes the string
+**
+** no file 'blabla.so'
+**	no file 'blublu.so'
+*/
+static void pusherrornotfound (lua_State *L, const char *path) {
+  luaL_Buffer b;
+  luaL_buffinit(L, &b);
+  luaL_addstring(&b, "no file '");
+  luaL_addgsub(&b, path, LUA_PATH_SEP, "'\n\tno file '");
+  luaL_addstring(&b, "'");
+  luaL_pushresult(&b);
+}
+
+
+static const char *searchpath (lua_State *L, const char *name,
+                                             const char *path,
+                                             const char *sep,
+                                             const char *dirsep) {
+  luaL_Buffer buff;
+  char *pathname;  /* path with name inserted */
+  char *endpathname;  /* its end */
+  const char *filename;
+  /* separator is non-empty and appears in 'name'? */
+  if (*sep != '\0' && strchr(name, *sep) != NULL)
+    name = luaL_gsub(L, name, sep, dirsep);  /* replace it by 'dirsep' */
+  luaL_buffinit(L, &buff);
+  /* add path to the buffer, replacing marks ('?') with the file name */
+  luaL_addgsub(&buff, path, LUA_PATH_MARK, name);
+  luaL_addchar(&buff, '\0');
+  pathname = luaL_buffaddr(&buff);  /* writable list of file names */
+  endpathname = pathname + luaL_bufflen(&buff) - 1;
+  while ((filename = getnextfilename(&pathname, endpathname)) != NULL) {
+    if (readable(filename))  /* does file exist and is readable? */
+      return lua_pushstring(L, filename);  /* save and return name */
+  }
+  luaL_pushresult(&buff);  /* push path to create error message */
+  pusherrornotfound(L, lua_tostring(L, -1));  /* create error message */
+  return NULL;  /* not found */
+}
+
+
+static int ll_searchpath (lua_State *L) {
+  const char *f = searchpath(L, luaL_checkstring(L, 1),
+                                luaL_checkstring(L, 2),
+                                luaL_optstring(L, 3, "."),
+                                luaL_optstring(L, 4, LUA_DIRSEP));
+  if (f != NULL) return 1;
+  else {  /* error message is on top of the stack */
+    luaL_pushfail(L);
+    lua_insert(L, -2);
+    return 2;  /* return fail + error message */
+  }
+}
+
+
+static const char *findfile (lua_State *L, const char *name,
+                                           const char *pname,
+                                           const char *dirsep) {
+  const char *path;
+  lua_getfield(L, lua_upvalueindex(1), pname);
+  path = lua_tostring(L, -1);
+  if (path == NULL)
+    luaL_error(L, "'package.%s' must be a string", pname);
+  return searchpath(L, name, path, ".", dirsep);
+}
+
+
+static int checkload (lua_State *L, int stat, const char *filename) {
+  if (stat) {  /* module loaded successfully? */
+    lua_pushstring(L, filename);  /* will be 2nd argument to module */
+    return 2;  /* return open function and file name */
+  }
+  else
+    return luaL_error(L, "error loading module '%s' from file '%s':\n\t%s",
+                          lua_tostring(L, 1), filename, lua_tostring(L, -1));
+}
+
+
+static int searcher_Lua (lua_State *L) {
+  const char *filename;
+  const char *name = luaL_checkstring(L, 1);
+  filename = findfile(L, name, "path", LUA_LSUBSEP);
+  if (filename == NULL) return 1;  /* module not found in this path */
+  return checkload(L, (luaL_loadfile(L, filename) == LUA_OK), filename);
+}
+
+
+/*
+** Try to find a load function for module 'modname' at file 'filename'.
+** First, change '.' to '_' in 'modname'; then, if 'modname' has
+** the form X-Y (that is, it has an "ignore mark"), build a function
+** name "luaopen_X" and look for it. (For compatibility, if that
+** fails, it also tries "luaopen_Y".) If there is no ignore mark,
+** look for a function named "luaopen_modname".
+*/
+static int loadfunc (lua_State *L, const char *filename, const char *modname) {
+  const char *openfunc;
+  const char *mark;
+  modname = luaL_gsub(L, modname, ".", LUA_OFSEP);
+  mark = strchr(modname, *LUA_IGMARK);
+  if (mark) {
+    int stat;
+    openfunc = lua_pushlstring(L, modname, mark - modname);
+    openfunc = lua_pushfstring(L, LUA_POF"%s", openfunc);
+    stat = lookforfunc(L, filename, openfunc);
+    if (stat != ERRFUNC) return stat;
+    modname = mark + 1;  /* else go ahead and try old-style name */
+  }
+  openfunc = lua_pushfstring(L, LUA_POF"%s", modname);
+  return lookforfunc(L, filename, openfunc);
+}
+
+
+static int searcher_C (lua_State *L) {
+  const char *name = luaL_checkstring(L, 1);
+  const char *filename = findfile(L, name, "cpath", LUA_CSUBSEP);
+  if (filename == NULL) return 1;  /* module not found in this path */
+  return checkload(L, (loadfunc(L, filename, name) == 0), filename);
+}
+
+
+static int searcher_Croot (lua_State *L) {
+  const char *filename;
+  const char *name = luaL_checkstring(L, 1);
+  const char *p = strchr(name, '.');
+  int stat;
+  if (p == NULL) return 0;  /* is root */
+  lua_pushlstring(L, name, p - name);
+  filename = findfile(L, lua_tostring(L, -1), "cpath", LUA_CSUBSEP);
+  if (filename == NULL) return 1;  /* root not found */
+  if ((stat = loadfunc(L, filename, name)) != 0) {
+    if (stat != ERRFUNC)
+      return checkload(L, 0, filename);  /* real error */
+    else {  /* open function not found */
+      lua_pushfstring(L, "no module '%s' in file '%s'", name, filename);
+      return 1;
+    }
+  }
+  lua_pushstring(L, filename);  /* will be 2nd argument to module */
+  return 2;
+}
+
+
+static int searcher_preload (lua_State *L) {
+  const char *name = luaL_checkstring(L, 1);
+  lua_getfield(L, LUA_REGISTRYINDEX, LUA_PRELOAD_TABLE);
+  if (lua_getfield(L, -1, name) == LUA_TNIL) {  /* not found? */
+    lua_pushfstring(L, "no field package.preload['%s']", name);
+    return 1;
+  }
+  else {
+    lua_pushliteral(L, ":preload:");
+    return 2;
+  }
+}
+
+
+static void findloader (lua_State *L, const char *name) {
+  int i;
+  luaL_Buffer msg;  /* to build error message */
+  /* push 'package.searchers' to index 3 in the stack */
+  if (lua_getfield(L, lua_upvalueindex(1), "searchers") != LUA_TTABLE)
+    luaL_error(L, "'package.searchers' must be a table");
+  luaL_buffinit(L, &msg);
+  /*  iterate over available searchers to find a loader */
+  for (i = 1; ; i++) {
+    luaL_addstring(&msg, "\n\t");  /* error-message prefix */
+    if (lua_rawgeti(L, 3, i) == LUA_TNIL) {  /* no more searchers? */
+      lua_pop(L, 1);  /* remove nil */
+      luaL_buffsub(&msg, 2);  /* remove prefix */
+      luaL_pushresult(&msg);  /* create error message */
+      luaL_error(L, "module '%s' not found:%s", name, lua_tostring(L, -1));
+    }
+    lua_pushstring(L, name);
+    lua_call(L, 1, 2);  /* call it */
+    if (lua_isfunction(L, -2))  /* did it find a loader? */
+      return;  /* module loader found */
+    else if (lua_isstring(L, -2)) {  /* searcher returned error message? */
+      lua_pop(L, 1);  /* remove extra return */
+      luaL_addvalue(&msg);  /* concatenate error message */
+    }
+    else {  /* no error message */
+      lua_pop(L, 2);  /* remove both returns */
+      luaL_buffsub(&msg, 2);  /* remove prefix */
+    }
+  }
+}
+
+
+static int ll_require (lua_State *L) {
+  const char *name = luaL_checkstring(L, 1);
+  lua_settop(L, 1);  /* LOADED table will be at index 2 */
+  lua_getfield(L, LUA_REGISTRYINDEX, LUA_LOADED_TABLE);
+  lua_getfield(L, 2, name);  /* LOADED[name] */
+  if (lua_toboolean(L, -1))  /* is it there? */
+    return 1;  /* package is already loaded */
+  /* else must load package */
+  lua_pop(L, 1);  /* remove 'getfield' result */
+  findloader(L, name);
+  lua_rotate(L, -2, 1);  /* function <-> loader data */
+  lua_pushvalue(L, 1);  /* name is 1st argument to module loader */
+  lua_pushvalue(L, -3);  /* loader data is 2nd argument */
+  /* stack: ...; loader data; loader function; mod. name; loader data */
+  lua_call(L, 2, 1);  /* run loader to load module */
+  /* stack: ...; loader data; result from loader */
+  if (!lua_isnil(L, -1))  /* non-nil return? */
+    lua_setfield(L, 2, name);  /* LOADED[name] = returned value */
+  else
+    lua_pop(L, 1);  /* pop nil */
+  if (lua_getfield(L, 2, name) == LUA_TNIL) {   /* module set no value? */
+    lua_pushboolean(L, 1);  /* use true as result */
+    lua_copy(L, -1, -2);  /* replace loader result */
+    lua_setfield(L, 2, name);  /* LOADED[name] = true */
+  }
+  lua_rotate(L, -2, 1);  /* loader data <-> module result  */
+  return 2;  /* return module result and loader data */
+}
+
+/* }====================================================== */
+
+
+
+
+static const luaL_Reg pk_funcs[] = {
+  {"loadlib", ll_loadlib},
+  {"searchpath", ll_searchpath},
+  /* placeholders */
+  {"preload", NULL},
+  {"cpath", NULL},
+  {"path", NULL},
+  {"searchers", NULL},
+  {"loaded", NULL},
+  {NULL, NULL}
+};
+
+
+static const luaL_Reg ll_funcs[] = {
+  {"require", ll_require},
+  {NULL, NULL}
+};
+
+
+static void createsearcherstable (lua_State *L) {
+  static const lua_CFunction searchers[] =
+    {searcher_preload, searcher_Lua, searcher_C, searcher_Croot, NULL};
+  int i;
+  /* create 'searchers' table */
+  lua_createtable(L, sizeof(searchers)/sizeof(searchers[0]) - 1, 0);
+  /* fill it with predefined searchers */
+  for (i=0; searchers[i] != NULL; i++) {
+    lua_pushvalue(L, -2);  /* set 'package' as upvalue for all searchers */
+    lua_pushcclosure(L, searchers[i], 1);
+    lua_rawseti(L, -2, i+1);
+  }
+  lua_setfield(L, -2, "searchers");  /* put it in field 'searchers' */
+}
+
+
+/*
+** create table CLIBS to keep track of loaded C libraries,
+** setting a finalizer to close all libraries when closing state.
+*/
+static void createclibstable (lua_State *L) {
+  luaL_getsubtable(L, LUA_REGISTRYINDEX, CLIBS);  /* create CLIBS table */
+  lua_createtable(L, 0, 1);  /* create metatable for CLIBS */
+  lua_pushcfunction(L, gctm);
+  lua_setfield(L, -2, "__gc");  /* set finalizer for CLIBS table */
+  lua_setmetatable(L, -2);
+}
+
+
+LUAMOD_API int luaopen_package (lua_State *L) {
+  createclibstable(L);
+  luaL_newlib(L, pk_funcs);  /* create 'package' table */
+  createsearcherstable(L);
+  /* set paths */
+  setpath(L, "path", LUA_PATH_VAR, LUA_PATH_DEFAULT);
+  setpath(L, "cpath", LUA_CPATH_VAR, LUA_CPATH_DEFAULT);
+  /* store config information */
+  lua_pushliteral(L, LUA_DIRSEP "\n" LUA_PATH_SEP "\n" LUA_PATH_MARK "\n"
+                     LUA_EXEC_DIR "\n" LUA_IGMARK "\n");
+  lua_setfield(L, -2, "config");
+  /* set field 'loaded' */
+  luaL_getsubtable(L, LUA_REGISTRYINDEX, LUA_LOADED_TABLE);
+  lua_setfield(L, -2, "loaded");
+  /* set field 'preload' */
+  luaL_getsubtable(L, LUA_REGISTRYINDEX, LUA_PRELOAD_TABLE);
+  lua_setfield(L, -2, "preload");
+  lua_pushglobaltable(L);
+  lua_pushvalue(L, -2);  /* set 'package' as upvalue for next lib */
+  luaL_setfuncs(L, ll_funcs, 1);  /* open lib into global table */
+  lua_pop(L, 1);  /* pop global table */
+  return 1;  /* return 'package' table */
+}
+
diff --git a/test/external/lua-5.4.0/src/lobject.c b/test/external/lua-5.4.0/src/lobject.c
new file mode 100644
index 0000000..b4efae4
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lobject.c
@@ -0,0 +1,583 @@
+/*
+** $Id: lobject.c $
+** Some generic functions over Lua objects
+** See Copyright Notice in lua.h
+*/
+
+#define lobject_c
+#define LUA_CORE
+
+#include "lprefix.h"
+
+
+#include <locale.h>
+#include <math.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "lua.h"
+
+#include "lctype.h"
+#include "ldebug.h"
+#include "ldo.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "lvm.h"
+
+
+/*
+** Computes ceil(log2(x))
+*/
+int luaO_ceillog2 (unsigned int x) {
+  static const lu_byte log_2[256] = {  /* log_2[i] = ceil(log2(i - 1)) */
+    0,1,2,2,3,3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
+    6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
+    7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+    7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+    8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
+    8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
+    8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
+    8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8
+  };
+  int l = 0;
+  x--;
+  while (x >= 256) { l += 8; x >>= 8; }
+  return l + log_2[x];
+}
+
+
+static lua_Integer intarith (lua_State *L, int op, lua_Integer v1,
+                                                   lua_Integer v2) {
+  switch (op) {
+    case LUA_OPADD: return intop(+, v1, v2);
+    case LUA_OPSUB:return intop(-, v1, v2);
+    case LUA_OPMUL:return intop(*, v1, v2);
+    case LUA_OPMOD: return luaV_mod(L, v1, v2);
+    case LUA_OPIDIV: return luaV_idiv(L, v1, v2);
+    case LUA_OPBAND: return intop(&, v1, v2);
+    case LUA_OPBOR: return intop(|, v1, v2);
+    case LUA_OPBXOR: return intop(^, v1, v2);
+    case LUA_OPSHL: return luaV_shiftl(v1, v2);
+    case LUA_OPSHR: return luaV_shiftl(v1, -v2);
+    case LUA_OPUNM: return intop(-, 0, v1);
+    case LUA_OPBNOT: return intop(^, ~l_castS2U(0), v1);
+    default: lua_assert(0); return 0;
+  }
+}
+
+
+static lua_Number numarith (lua_State *L, int op, lua_Number v1,
+                                                  lua_Number v2) {
+  switch (op) {
+    case LUA_OPADD: return luai_numadd(L, v1, v2);
+    case LUA_OPSUB: return luai_numsub(L, v1, v2);
+    case LUA_OPMUL: return luai_nummul(L, v1, v2);
+    case LUA_OPDIV: return luai_numdiv(L, v1, v2);
+    case LUA_OPPOW: return luai_numpow(L, v1, v2);
+    case LUA_OPIDIV: return luai_numidiv(L, v1, v2);
+    case LUA_OPUNM: return luai_numunm(L, v1);
+    case LUA_OPMOD: return luaV_modf(L, v1, v2);
+    default: lua_assert(0); return 0;
+  }
+}
+
+
+int luaO_rawarith (lua_State *L, int op, const TValue *p1, const TValue *p2,
+                   TValue *res) {
+  switch (op) {
+    case LUA_OPBAND: case LUA_OPBOR: case LUA_OPBXOR:
+    case LUA_OPSHL: case LUA_OPSHR:
+    case LUA_OPBNOT: {  /* operate only on integers */
+      lua_Integer i1; lua_Integer i2;
+      if (tointegerns(p1, &i1) && tointegerns(p2, &i2)) {
+        setivalue(res, intarith(L, op, i1, i2));
+        return 1;
+      }
+      else return 0;  /* fail */
+    }
+    case LUA_OPDIV: case LUA_OPPOW: {  /* operate only on floats */
+      lua_Number n1; lua_Number n2;
+      if (tonumberns(p1, n1) && tonumberns(p2, n2)) {
+        setfltvalue(res, numarith(L, op, n1, n2));
+        return 1;
+      }
+      else return 0;  /* fail */
+    }
+    default: {  /* other operations */
+      lua_Number n1; lua_Number n2;
+      if (ttisinteger(p1) && ttisinteger(p2)) {
+        setivalue(res, intarith(L, op, ivalue(p1), ivalue(p2)));
+        return 1;
+      }
+      else if (tonumberns(p1, n1) && tonumberns(p2, n2)) {
+        setfltvalue(res, numarith(L, op, n1, n2));
+        return 1;
+      }
+      else return 0;  /* fail */
+    }
+  }
+}
+
+
+void luaO_arith (lua_State *L, int op, const TValue *p1, const TValue *p2,
+                 StkId res) {
+  if (!luaO_rawarith(L, op, p1, p2, s2v(res))) {
+    /* could not perform raw operation; try metamethod */
+    luaT_trybinTM(L, p1, p2, res, cast(TMS, (op - LUA_OPADD) + TM_ADD));
+  }
+}
+
+
+int luaO_hexavalue (int c) {
+  if (lisdigit(c)) return c - '0';
+  else return (ltolower(c) - 'a') + 10;
+}
+
+
+static int isneg (const char **s) {
+  if (**s == '-') { (*s)++; return 1; }
+  else if (**s == '+') (*s)++;
+  return 0;
+}
+
+
+
+/*
+** {==================================================================
+** Lua's implementation for 'lua_strx2number'
+** ===================================================================
+*/
+
+#if !defined(lua_strx2number)
+
+/* maximum number of significant digits to read (to avoid overflows
+   even with single floats) */
+#define MAXSIGDIG	30
+
+/*
+** convert a hexadecimal numeric string to a number, following
+** C99 specification for 'strtod'
+*/
+static lua_Number lua_strx2number (const char *s, char **endptr) {
+  int dot = lua_getlocaledecpoint();
+  lua_Number r = 0.0;  /* result (accumulator) */
+  int sigdig = 0;  /* number of significant digits */
+  int nosigdig = 0;  /* number of non-significant digits */
+  int e = 0;  /* exponent correction */
+  int neg;  /* 1 if number is negative */
+  int hasdot = 0;  /* true after seen a dot */
+  *endptr = cast_charp(s);  /* nothing is valid yet */
+  while (lisspace(cast_uchar(*s))) s++;  /* skip initial spaces */
+  neg = isneg(&s);  /* check sign */
+  if (!(*s == '0' && (*(s + 1) == 'x' || *(s + 1) == 'X')))  /* check '0x' */
+    return 0.0;  /* invalid format (no '0x') */
+  for (s += 2; ; s++) {  /* skip '0x' and read numeral */
+    if (*s == dot) {
+      if (hasdot) break;  /* second dot? stop loop */
+      else hasdot = 1;
+    }
+    else if (lisxdigit(cast_uchar(*s))) {
+      if (sigdig == 0 && *s == '0')  /* non-significant digit (zero)? */
+        nosigdig++;
+      else if (++sigdig <= MAXSIGDIG)  /* can read it without overflow? */
+          r = (r * cast_num(16.0)) + luaO_hexavalue(*s);
+      else e++; /* too many digits; ignore, but still count for exponent */
+      if (hasdot) e--;  /* decimal digit? correct exponent */
+    }
+    else break;  /* neither a dot nor a digit */
+  }
+  if (nosigdig + sigdig == 0)  /* no digits? */
+    return 0.0;  /* invalid format */
+  *endptr = cast_charp(s);  /* valid up to here */
+  e *= 4;  /* each digit multiplies/divides value by 2^4 */
+  if (*s == 'p' || *s == 'P') {  /* exponent part? */
+    int exp1 = 0;  /* exponent value */
+    int neg1;  /* exponent sign */
+    s++;  /* skip 'p' */
+    neg1 = isneg(&s);  /* sign */
+    if (!lisdigit(cast_uchar(*s)))
+      return 0.0;  /* invalid; must have at least one digit */
+    while (lisdigit(cast_uchar(*s)))  /* read exponent */
+      exp1 = exp1 * 10 + *(s++) - '0';
+    if (neg1) exp1 = -exp1;
+    e += exp1;
+    *endptr = cast_charp(s);  /* valid up to here */
+  }
+  if (neg) r = -r;
+  return l_mathop(ldexp)(r, e);
+}
+
+#endif
+/* }====================================================== */
+
+
+/* maximum length of a numeral */
+#if !defined (L_MAXLENNUM)
+#define L_MAXLENNUM	200
+#endif
+
+static const char *l_str2dloc (const char *s, lua_Number *result, int mode) {
+  char *endptr;
+  *result = (mode == 'x') ? lua_strx2number(s, &endptr)  /* try to convert */
+                          : lua_str2number(s, &endptr);
+  if (endptr == s) return NULL;  /* nothing recognized? */
+  while (lisspace(cast_uchar(*endptr))) endptr++;  /* skip trailing spaces */
+  return (*endptr == '\0') ? endptr : NULL;  /* OK if no trailing characters */
+}
+
+
+/*
+** Convert string 's' to a Lua number (put in 'result'). Return NULL
+** on fail or the address of the ending '\0' on success.
+** 'pmode' points to (and 'mode' contains) special things in the string:
+** - 'x'/'X' means a hexadecimal numeral
+** - 'n'/'N' means 'inf' or 'nan' (which should be rejected)
+** - '.' just optimizes the search for the common case (nothing special)
+** This function accepts both the current locale or a dot as the radix
+** mark. If the conversion fails, it may mean number has a dot but
+** locale accepts something else. In that case, the code copies 's'
+** to a buffer (because 's' is read-only), changes the dot to the
+** current locale radix mark, and tries to convert again.
+*/
+static const char *l_str2d (const char *s, lua_Number *result) {
+  const char *endptr;
+  const char *pmode = strpbrk(s, ".xXnN");
+  int mode = pmode ? ltolower(cast_uchar(*pmode)) : 0;
+  if (mode == 'n')  /* reject 'inf' and 'nan' */
+    return NULL;
+  endptr = l_str2dloc(s, result, mode);  /* try to convert */
+  if (endptr == NULL) {  /* failed? may be a different locale */
+    char buff[L_MAXLENNUM + 1];
+    const char *pdot = strchr(s, '.');
+    if (strlen(s) > L_MAXLENNUM || pdot == NULL)
+      return NULL;  /* string too long or no dot; fail */
+    strcpy(buff, s);  /* copy string to buffer */
+    buff[pdot - s] = lua_getlocaledecpoint();  /* correct decimal point */
+    endptr = l_str2dloc(buff, result, mode);  /* try again */
+    if (endptr != NULL)
+      endptr = s + (endptr - buff);  /* make relative to 's' */
+  }
+  return endptr;
+}
+
+
+#define MAXBY10		cast(lua_Unsigned, LUA_MAXINTEGER / 10)
+#define MAXLASTD	cast_int(LUA_MAXINTEGER % 10)
+
+static const char *l_str2int (const char *s, lua_Integer *result) {
+  lua_Unsigned a = 0;
+  int empty = 1;
+  int neg;
+  while (lisspace(cast_uchar(*s))) s++;  /* skip initial spaces */
+  neg = isneg(&s);
+  if (s[0] == '0' &&
+      (s[1] == 'x' || s[1] == 'X')) {  /* hex? */
+    s += 2;  /* skip '0x' */
+    for (; lisxdigit(cast_uchar(*s)); s++) {
+      a = a * 16 + luaO_hexavalue(*s);
+      empty = 0;
+    }
+  }
+  else {  /* decimal */
+    for (; lisdigit(cast_uchar(*s)); s++) {
+      int d = *s - '0';
+      if (a >= MAXBY10 && (a > MAXBY10 || d > MAXLASTD + neg))  /* overflow? */
+        return NULL;  /* do not accept it (as integer) */
+      a = a * 10 + d;
+      empty = 0;
+    }
+  }
+  while (lisspace(cast_uchar(*s))) s++;  /* skip trailing spaces */
+  if (empty || *s != '\0') return NULL;  /* something wrong in the numeral */
+  else {
+    *result = l_castU2S((neg) ? 0u - a : a);
+    return s;
+  }
+}
+
+
+size_t luaO_str2num (const char *s, TValue *o) {
+  lua_Integer i; lua_Number n;
+  const char *e;
+  if ((e = l_str2int(s, &i)) != NULL) {  /* try as an integer */
+    setivalue(o, i);
+  }
+  else if ((e = l_str2d(s, &n)) != NULL) {  /* else try as a float */
+    setfltvalue(o, n);
+  }
+  else
+    return 0;  /* conversion failed */
+  return (e - s) + 1;  /* success; return string size */
+}
+
+
+int luaO_utf8esc (char *buff, unsigned long x) {
+  int n = 1;  /* number of bytes put in buffer (backwards) */
+  lua_assert(x <= 0x7FFFFFFFu);
+  if (x < 0x80)  /* ascii? */
+    buff[UTF8BUFFSZ - 1] = cast_char(x);
+  else {  /* need continuation bytes */
+    unsigned int mfb = 0x3f;  /* maximum that fits in first byte */
+    do {  /* add continuation bytes */
+      buff[UTF8BUFFSZ - (n++)] = cast_char(0x80 | (x & 0x3f));
+      x >>= 6;  /* remove added bits */
+      mfb >>= 1;  /* now there is one less bit available in first byte */
+    } while (x > mfb);  /* still needs continuation byte? */
+    buff[UTF8BUFFSZ - n] = cast_char((~mfb << 1) | x);  /* add first byte */
+  }
+  return n;
+}
+
+
+/* maximum length of the conversion of a number to a string */
+#define MAXNUMBER2STR	50
+
+
+/*
+** Convert a number object to a string, adding it to a buffer
+*/
+static int tostringbuff (TValue *obj, char *buff) {
+  int len;
+  lua_assert(ttisnumber(obj));
+  if (ttisinteger(obj))
+    len = lua_integer2str(buff, MAXNUMBER2STR, ivalue(obj));
+  else {
+    len = lua_number2str(buff, MAXNUMBER2STR, fltvalue(obj));
+    if (buff[strspn(buff, "-0123456789")] == '\0') {  /* looks like an int? */
+      buff[len++] = lua_getlocaledecpoint();
+      buff[len++] = '0';  /* adds '.0' to result */
+    }
+  }
+  return len;
+}
+
+
+/*
+** Convert a number object to a Lua string, replacing the value at 'obj'
+*/
+void luaO_tostring (lua_State *L, TValue *obj) {
+  char buff[MAXNUMBER2STR];
+  int len = tostringbuff(obj, buff);
+  setsvalue(L, obj, luaS_newlstr(L, buff, len));
+}
+
+
+
+
+/*
+** {==================================================================
+** 'luaO_pushvfstring'
+** ===================================================================
+*/
+
+/* size for buffer space used by 'luaO_pushvfstring' */
+#define BUFVFS		400
+
+/* buffer used by 'luaO_pushvfstring' */
+typedef struct BuffFS {
+  lua_State *L;
+  int pushed;  /* number of string pieces already on the stack */
+  int blen;  /* length of partial string in 'space' */
+  char space[BUFVFS];  /* holds last part of the result */
+} BuffFS;
+
+
+/*
+** Push given string to the stack, as part of the buffer. If the stack
+** is almost full, join all partial strings in the stack into one.
+*/
+static void pushstr (BuffFS *buff, const char *str, size_t l) {
+  lua_State *L = buff->L;
+  setsvalue2s(L, L->top, luaS_newlstr(L, str, l));
+  L->top++;  /* may use one extra slot */
+  buff->pushed++;
+  if (buff->pushed > 1 && L->top + 1 >= L->stack_last) {
+    luaV_concat(L, buff->pushed);  /* join all partial results into one */
+    buff->pushed = 1;
+  }
+}
+
+
+/*
+** empty the buffer space into the stack
+*/
+static void clearbuff (BuffFS *buff) {
+  pushstr(buff, buff->space, buff->blen);  /* push buffer contents */
+  buff->blen = 0;  /* space now is empty */
+}
+
+
+/*
+** Get a space of size 'sz' in the buffer. If buffer has not enough
+** space, empty it. 'sz' must fit in an empty buffer.
+*/
+static char *getbuff (BuffFS *buff, int sz) {
+  lua_assert(buff->blen <= BUFVFS); lua_assert(sz <= BUFVFS);
+  if (sz > BUFVFS - buff->blen)  /* not enough space? */
+    clearbuff(buff);
+  return buff->space + buff->blen;
+}
+
+
+#define addsize(b,sz)	((b)->blen += (sz))
+
+
+/*
+** Add 'str' to the buffer. If string is larger than the buffer space,
+** push the string directly to the stack.
+*/
+static void addstr2buff (BuffFS *buff, const char *str, size_t slen) {
+  if (slen <= BUFVFS) {  /* does string fit into buffer? */
+    char *bf = getbuff(buff, cast_int(slen));
+    memcpy(bf, str, slen);  /* add string to buffer */
+    addsize(buff, cast_int(slen));
+  }
+  else {  /* string larger than buffer */
+    clearbuff(buff);  /* string comes after buffer's content */
+    pushstr(buff, str, slen);  /* push string */
+  }
+}
+
+
+/*
+** Add a number to the buffer.
+*/
+static void addnum2buff (BuffFS *buff, TValue *num) {
+  char *numbuff = getbuff(buff, MAXNUMBER2STR);
+  int len = tostringbuff(num, numbuff);  /* format number into 'numbuff' */
+  addsize(buff, len);
+}
+
+
+/*
+** this function handles only '%d', '%c', '%f', '%p', '%s', and '%%'
+   conventional formats, plus Lua-specific '%I' and '%U'
+*/
+const char *luaO_pushvfstring (lua_State *L, const char *fmt, va_list argp) {
+  BuffFS buff;  /* holds last part of the result */
+  const char *e;  /* points to next '%' */
+  buff.pushed = buff.blen = 0;
+  buff.L = L;
+  while ((e = strchr(fmt, '%')) != NULL) {
+    addstr2buff(&buff, fmt, e - fmt);  /* add 'fmt' up to '%' */
+    switch (*(e + 1)) {  /* conversion specifier */
+      case 's': {  /* zero-terminated string */
+        const char *s = va_arg(argp, char *);
+        if (s == NULL) s = "(null)";
+        addstr2buff(&buff, s, strlen(s));
+        break;
+      }
+      case 'c': {  /* an 'int' as a character */
+        char c = cast_uchar(va_arg(argp, int));
+        addstr2buff(&buff, &c, sizeof(char));
+        break;
+      }
+      case 'd': {  /* an 'int' */
+        TValue num;
+        setivalue(&num, va_arg(argp, int));
+        addnum2buff(&buff, &num);
+        break;
+      }
+      case 'I': {  /* a 'lua_Integer' */
+        TValue num;
+        setivalue(&num, cast(lua_Integer, va_arg(argp, l_uacInt)));
+        addnum2buff(&buff, &num);
+        break;
+      }
+      case 'f': {  /* a 'lua_Number' */
+        TValue num;
+        setfltvalue(&num, cast_num(va_arg(argp, l_uacNumber)));
+        addnum2buff(&buff, &num);
+        break;
+      }
+      case 'p': {  /* a pointer */
+        const int sz = 3 * sizeof(void*) + 8; /* enough space for '%p' */
+        char *bf = getbuff(&buff, sz);
+        void *p = va_arg(argp, void *);
+        int len = lua_pointer2str(bf, sz, p);
+        addsize(&buff, len);
+        break;
+      }
+      case 'U': {  /* a 'long' as a UTF-8 sequence */
+        char bf[UTF8BUFFSZ];
+        int len = luaO_utf8esc(bf, va_arg(argp, long));
+        addstr2buff(&buff, bf + UTF8BUFFSZ - len, len);
+        break;
+      }
+      case '%': {
+        addstr2buff(&buff, "%", 1);
+        break;
+      }
+      default: {
+        luaG_runerror(L, "invalid option '%%%c' to 'lua_pushfstring'",
+                         *(e + 1));
+      }
+    }
+    fmt = e + 2;  /* skip '%' and the specifier */
+  }
+  addstr2buff(&buff, fmt, strlen(fmt));  /* rest of 'fmt' */
+  clearbuff(&buff);  /* empty buffer into the stack */
+  if (buff.pushed > 1)
+    luaV_concat(L, buff.pushed);  /* join all partial results */
+  return svalue(s2v(L->top - 1));
+}
+
+
+const char *luaO_pushfstring (lua_State *L, const char *fmt, ...) {
+  const char *msg;
+  va_list argp;
+  va_start(argp, fmt);
+  msg = luaO_pushvfstring(L, fmt, argp);
+  va_end(argp);
+  return msg;
+}
+
+/* }================================================================== */
+
+
+#define RETS	"..."
+#define PRE	"[string \""
+#define POS	"\"]"
+
+#define addstr(a,b,l)	( memcpy(a,b,(l) * sizeof(char)), a += (l) )
+
+void luaO_chunkid (char *out, const char *source, size_t srclen) {
+  size_t bufflen = LUA_IDSIZE;  /* free space in buffer */
+  if (*source == '=') {  /* 'literal' source */
+    if (srclen <= bufflen)  /* small enough? */
+      memcpy(out, source + 1, srclen * sizeof(char));
+    else {  /* truncate it */
+      addstr(out, source + 1, bufflen - 1);
+      *out = '\0';
+    }
+  }
+  else if (*source == '@') {  /* file name */
+    if (srclen <= bufflen)  /* small enough? */
+      memcpy(out, source + 1, srclen * sizeof(char));
+    else {  /* add '...' before rest of name */
+      addstr(out, RETS, LL(RETS));
+      bufflen -= LL(RETS);
+      memcpy(out, source + 1 + srclen - bufflen, bufflen * sizeof(char));
+    }
+  }
+  else {  /* string; format as [string "source"] */
+    const char *nl = strchr(source, '\n');  /* find first new line (if any) */
+    addstr(out, PRE, LL(PRE));  /* add prefix */
+    bufflen -= LL(PRE RETS POS) + 1;  /* save space for prefix+suffix+'\0' */
+    if (srclen < bufflen && nl == NULL) {  /* small one-line source? */
+      addstr(out, source, srclen);  /* keep it */
+    }
+    else {
+      if (nl != NULL) srclen = nl - source;  /* stop at first newline */
+      if (srclen > bufflen) srclen = bufflen;
+      addstr(out, source, srclen);
+      addstr(out, RETS, LL(RETS));
+    }
+    memcpy(out, POS, (LL(POS) + 1) * sizeof(char));
+  }
+}
+
diff --git a/test/external/lua-5.4.0/src/lobject.h b/test/external/lua-5.4.0/src/lobject.h
new file mode 100644
index 0000000..04a81d3
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lobject.h
@@ -0,0 +1,787 @@
+/*
+** $Id: lobject.h $
+** Type definitions for Lua objects
+** See Copyright Notice in lua.h
+*/
+
+
+#ifndef lobject_h
+#define lobject_h
+
+
+#include <stdarg.h>
+
+
+#include "llimits.h"
+#include "lua.h"
+
+
+/*
+** Extra types for collectable non-values
+*/
+#define LUA_TUPVAL	LUA_NUMTYPES  /* upvalues */
+#define LUA_TPROTO	(LUA_NUMTYPES+1)  /* function prototypes */
+
+
+/*
+** number of all possible types (including LUA_TNONE)
+*/
+#define LUA_TOTALTYPES		(LUA_TPROTO + 2)
+
+
+/*
+** tags for Tagged Values have the following use of bits:
+** bits 0-3: actual tag (a LUA_T* constant)
+** bits 4-5: variant bits
+** bit 6: whether value is collectable
+*/
+
+/* add variant bits to a type */
+#define makevariant(t,v)	((t) | ((v) << 4))
+
+
+
+/*
+** Union of all Lua values
+*/
+typedef union Value {
+  struct GCObject *gc;    /* collectable objects */
+  void *p;         /* light userdata */
+  lua_CFunction f; /* light C functions */
+  lua_Integer i;   /* integer numbers */
+  lua_Number n;    /* float numbers */
+} Value;
+
+
+/*
+** Tagged Values. This is the basic representation of values in Lua:
+** an actual value plus a tag with its type.
+*/
+
+#define TValuefields	Value value_; lu_byte tt_
+
+typedef struct TValue {
+  TValuefields;
+} TValue;
+
+
+#define val_(o)		((o)->value_)
+#define valraw(o)	(&val_(o))
+
+
+/* raw type tag of a TValue */
+#define rawtt(o)	((o)->tt_)
+
+/* tag with no variants (bits 0-3) */
+#define novariant(t)	((t) & 0x0F)
+
+/* type tag of a TValue (bits 0-3 for tags + variant bits 4-5) */
+#define withvariant(t)	((t) & 0x3F)
+#define ttypetag(o)	withvariant(rawtt(o))
+
+/* type of a TValue */
+#define ttype(o)	(novariant(rawtt(o)))
+
+
+/* Macros to test type */
+#define checktag(o,t)		(rawtt(o) == (t))
+#define checktype(o,t)		(ttype(o) == (t))
+
+
+/* Macros for internal tests */
+
+/* collectable object has the same tag as the original value */
+#define righttt(obj)		(ttypetag(obj) == gcvalue(obj)->tt)
+
+/*
+** Any value being manipulated by the program either is non
+** collectable, or the collectable object has the right tag
+** and it is not dead.
+*/
+#define checkliveness(L,obj) \
+	((void)L, lua_longassert(!iscollectable(obj) || \
+		(righttt(obj) && (L == NULL || !isdead(G(L),gcvalue(obj))))))
+
+
+/* Macros to set values */
+
+/* set a value's tag */
+#define settt_(o,t)	((o)->tt_=(t))
+
+
+/* main macro to copy values (from 'obj1' to 'obj2') */
+#define setobj(L,obj1,obj2) \
+	{ TValue *io1=(obj1); const TValue *io2=(obj2); \
+          io1->value_ = io2->value_; settt_(io1, io2->tt_); \
+	  checkliveness(L,io1); lua_assert(!isnonstrictnil(io1)); }
+
+/*
+** Different types of assignments, according to source and destination.
+** (They are mostly equal now, but may be different in the future.)
+*/
+
+/* from stack to stack */
+#define setobjs2s(L,o1,o2)	setobj(L,s2v(o1),s2v(o2))
+/* to stack (not from same stack) */
+#define setobj2s(L,o1,o2)	setobj(L,s2v(o1),o2)
+/* from table to same table */
+#define setobjt2t	setobj
+/* to new object */
+#define setobj2n	setobj
+/* to table */
+#define setobj2t	setobj
+
+
+/*
+** Entries in the Lua stack
+*/
+typedef union StackValue {
+  TValue val;
+} StackValue;
+
+
+/* index to stack elements */
+typedef StackValue *StkId;
+
+/* convert a 'StackValue' to a 'TValue' */
+#define s2v(o)	(&(o)->val)
+
+
+
+/*
+** {==================================================================
+** Nil
+** ===================================================================
+*/
+
+/* Standard nil */
+#define LUA_VNIL	makevariant(LUA_TNIL, 0)
+
+/* Empty slot (which might be different from a slot containing nil) */
+#define LUA_VEMPTY	makevariant(LUA_TNIL, 1)
+
+/* Value returned for a key not found in a table (absent key) */
+#define LUA_VABSTKEY	makevariant(LUA_TNIL, 2)
+
+
+/* macro to test for (any kind of) nil */
+#define ttisnil(v)		checktype((v), LUA_TNIL)
+
+
+/* macro to test for a standard nil */
+#define ttisstrictnil(o)	checktag((o), LUA_VNIL)
+
+
+#define setnilvalue(obj) settt_(obj, LUA_VNIL)
+
+
+#define isabstkey(v)		checktag((v), LUA_VABSTKEY)
+
+
+/*
+** macro to detect non-standard nils (used only in assertions)
+*/
+#define isnonstrictnil(v)	(ttisnil(v) && !ttisstrictnil(v))
+
+
+/*
+** By default, entries with any kind of nil are considered empty.
+** (In any definition, values associated with absent keys must also
+** be accepted as empty.)
+*/
+#define isempty(v)		ttisnil(v)
+
+
+/* macro defining a value corresponding to an absent key */
+#define ABSTKEYCONSTANT		{NULL}, LUA_VABSTKEY
+
+
+/* mark an entry as empty */
+#define setempty(v)		settt_(v, LUA_VEMPTY)
+
+
+
+/* }================================================================== */
+
+
+/*
+** {==================================================================
+** Booleans
+** ===================================================================
+*/
+
+
+#define LUA_VFALSE	makevariant(LUA_TBOOLEAN, 0)
+#define LUA_VTRUE	makevariant(LUA_TBOOLEAN, 1)
+
+#define ttisboolean(o)		checktype((o), LUA_TBOOLEAN)
+#define ttisfalse(o)		checktag((o), LUA_VFALSE)
+#define ttistrue(o)		checktag((o), LUA_VTRUE)
+
+
+#define l_isfalse(o)	(ttisfalse(o) || ttisnil(o))
+
+
+#define setbfvalue(obj)		settt_(obj, LUA_VFALSE)
+#define setbtvalue(obj)		settt_(obj, LUA_VTRUE)
+
+/* }================================================================== */
+
+
+/*
+** {==================================================================
+** Threads
+** ===================================================================
+*/
+
+#define LUA_VTHREAD		makevariant(LUA_TTHREAD, 0)
+
+#define ttisthread(o)		checktag((o), ctb(LUA_VTHREAD))
+
+#define thvalue(o)	check_exp(ttisthread(o), gco2th(val_(o).gc))
+
+#define setthvalue(L,obj,x) \
+  { TValue *io = (obj); lua_State *x_ = (x); \
+    val_(io).gc = obj2gco(x_); settt_(io, ctb(LUA_VTHREAD)); \
+    checkliveness(L,io); }
+
+#define setthvalue2s(L,o,t)	setthvalue(L,s2v(o),t)
+
+/* }================================================================== */
+
+
+/*
+** {==================================================================
+** Collectable Objects
+** ===================================================================
+*/
+
+/*
+** Common Header for all collectable objects (in macro form, to be
+** included in other objects)
+*/
+#define CommonHeader	struct GCObject *next; lu_byte tt; lu_byte marked
+
+
+/* Common type for all collectable objects */
+typedef struct GCObject {
+  CommonHeader;
+} GCObject;
+
+
+/* Bit mark for collectable types */
+#define BIT_ISCOLLECTABLE	(1 << 6)
+
+#define iscollectable(o)	(rawtt(o) & BIT_ISCOLLECTABLE)
+
+/* mark a tag as collectable */
+#define ctb(t)			((t) | BIT_ISCOLLECTABLE)
+
+#define gcvalue(o)	check_exp(iscollectable(o), val_(o).gc)
+
+#define gcvalueraw(v)	((v).gc)
+
+#define setgcovalue(L,obj,x) \
+  { TValue *io = (obj); GCObject *i_g=(x); \
+    val_(io).gc = i_g; settt_(io, ctb(i_g->tt)); }
+
+/* }================================================================== */
+
+
+/*
+** {==================================================================
+** Numbers
+** ===================================================================
+*/
+
+/* Variant tags for numbers */
+#define LUA_VNUMINT	makevariant(LUA_TNUMBER, 0)  /* integer numbers */
+#define LUA_VNUMFLT	makevariant(LUA_TNUMBER, 1)  /* float numbers */
+
+#define ttisnumber(o)		checktype((o), LUA_TNUMBER)
+#define ttisfloat(o)		checktag((o), LUA_VNUMFLT)
+#define ttisinteger(o)		checktag((o), LUA_VNUMINT)
+
+#define nvalue(o)	check_exp(ttisnumber(o), \
+	(ttisinteger(o) ? cast_num(ivalue(o)) : fltvalue(o)))
+#define fltvalue(o)	check_exp(ttisfloat(o), val_(o).n)
+#define ivalue(o)	check_exp(ttisinteger(o), val_(o).i)
+
+#define fltvalueraw(v)	((v).n)
+#define ivalueraw(v)	((v).i)
+
+#define setfltvalue(obj,x) \
+  { TValue *io=(obj); val_(io).n=(x); settt_(io, LUA_VNUMFLT); }
+
+#define chgfltvalue(obj,x) \
+  { TValue *io=(obj); lua_assert(ttisfloat(io)); val_(io).n=(x); }
+
+#define setivalue(obj,x) \
+  { TValue *io=(obj); val_(io).i=(x); settt_(io, LUA_VNUMINT); }
+
+#define chgivalue(obj,x) \
+  { TValue *io=(obj); lua_assert(ttisinteger(io)); val_(io).i=(x); }
+
+/* }================================================================== */
+
+
+/*
+** {==================================================================
+** Strings
+** ===================================================================
+*/
+
+/* Variant tags for strings */
+#define LUA_VSHRSTR	makevariant(LUA_TSTRING, 0)  /* short strings */
+#define LUA_VLNGSTR	makevariant(LUA_TSTRING, 1)  /* long strings */
+
+#define ttisstring(o)		checktype((o), LUA_TSTRING)
+#define ttisshrstring(o)	checktag((o), ctb(LUA_VSHRSTR))
+#define ttislngstring(o)	checktag((o), ctb(LUA_VLNGSTR))
+
+#define tsvalueraw(v)	(gco2ts((v).gc))
+
+#define tsvalue(o)	check_exp(ttisstring(o), gco2ts(val_(o).gc))
+
+#define setsvalue(L,obj,x) \
+  { TValue *io = (obj); TString *x_ = (x); \
+    val_(io).gc = obj2gco(x_); settt_(io, ctb(x_->tt)); \
+    checkliveness(L,io); }
+
+/* set a string to the stack */
+#define setsvalue2s(L,o,s)	setsvalue(L,s2v(o),s)
+
+/* set a string to a new object */
+#define setsvalue2n	setsvalue
+
+
+/*
+** Header for a string value.
+*/
+typedef struct TString {
+  CommonHeader;
+  lu_byte extra;  /* reserved words for short strings; "has hash" for longs */
+  lu_byte shrlen;  /* length for short strings */
+  unsigned int hash;
+  union {
+    size_t lnglen;  /* length for long strings */
+    struct TString *hnext;  /* linked list for hash table */
+  } u;
+  char contents[1];
+} TString;
+
+
+
+/*
+** Get the actual string (array of bytes) from a 'TString'.
+*/
+#define getstr(ts)  ((ts)->contents)
+
+
+/* get the actual string (array of bytes) from a Lua value */
+#define svalue(o)       getstr(tsvalue(o))
+
+/* get string length from 'TString *s' */
+#define tsslen(s)	((s)->tt == LUA_VSHRSTR ? (s)->shrlen : (s)->u.lnglen)
+
+/* get string length from 'TValue *o' */
+#define vslen(o)	tsslen(tsvalue(o))
+
+/* }================================================================== */
+
+
+/*
+** {==================================================================
+** Userdata
+** ===================================================================
+*/
+
+
+/*
+** Light userdata should be a variant of userdata, but for compatibility
+** reasons they are also different types.
+*/
+#define LUA_VLIGHTUSERDATA	makevariant(LUA_TLIGHTUSERDATA, 0)
+
+#define LUA_VUSERDATA		makevariant(LUA_TUSERDATA, 0)
+
+#define ttislightuserdata(o)	checktag((o), LUA_VLIGHTUSERDATA)
+#define ttisfulluserdata(o)	checktag((o), ctb(LUA_VUSERDATA))
+
+#define pvalue(o)	check_exp(ttislightuserdata(o), val_(o).p)
+#define uvalue(o)	check_exp(ttisfulluserdata(o), gco2u(val_(o).gc))
+
+#define pvalueraw(v)	((v).p)
+
+#define setpvalue(obj,x) \
+  { TValue *io=(obj); val_(io).p=(x); settt_(io, LUA_VLIGHTUSERDATA); }
+
+#define setuvalue(L,obj,x) \
+  { TValue *io = (obj); Udata *x_ = (x); \
+    val_(io).gc = obj2gco(x_); settt_(io, ctb(LUA_VUSERDATA)); \
+    checkliveness(L,io); }
+
+
+/* Ensures that addresses after this type are always fully aligned. */
+typedef union UValue {
+  TValue uv;
+  LUAI_MAXALIGN;  /* ensures maximum alignment for udata bytes */
+} UValue;
+
+
+/*
+** Header for userdata with user values;
+** memory area follows the end of this structure.
+*/
+typedef struct Udata {
+  CommonHeader;
+  unsigned short nuvalue;  /* number of user values */
+  size_t len;  /* number of bytes */
+  struct Table *metatable;
+  GCObject *gclist;
+  UValue uv[1];  /* user values */
+} Udata;
+
+
+/*
+** Header for userdata with no user values. These userdata do not need
+** to be gray during GC, and therefore do not need a 'gclist' field.
+** To simplify, the code always use 'Udata' for both kinds of userdata,
+** making sure it never accesses 'gclist' on userdata with no user values.
+** This structure here is used only to compute the correct size for
+** this representation. (The 'bindata' field in its end ensures correct
+** alignment for binary data following this header.)
+*/
+typedef struct Udata0 {
+  CommonHeader;
+  unsigned short nuvalue;  /* number of user values */
+  size_t len;  /* number of bytes */
+  struct Table *metatable;
+  union {LUAI_MAXALIGN;} bindata;
+} Udata0;
+
+
+/* compute the offset of the memory area of a userdata */
+#define udatamemoffset(nuv) \
+	((nuv) == 0 ? offsetof(Udata0, bindata)  \
+                    : offsetof(Udata, uv) + (sizeof(UValue) * (nuv)))
+
+/* get the address of the memory block inside 'Udata' */
+#define getudatamem(u)	(cast_charp(u) + udatamemoffset((u)->nuvalue))
+
+/* compute the size of a userdata */
+#define sizeudata(nuv,nb)	(udatamemoffset(nuv) + (nb))
+
+/* }================================================================== */
+
+
+/*
+** {==================================================================
+** Prototypes
+** ===================================================================
+*/
+
+#define LUA_VPROTO	makevariant(LUA_TPROTO, 0)
+
+
+/*
+** Description of an upvalue for function prototypes
+*/
+typedef struct Upvaldesc {
+  TString *name;  /* upvalue name (for debug information) */
+  lu_byte instack;  /* whether it is in stack (register) */
+  lu_byte idx;  /* index of upvalue (in stack or in outer function's list) */
+  lu_byte kind;  /* kind of corresponding variable */
+} Upvaldesc;
+
+
+/*
+** Description of a local variable for function prototypes
+** (used for debug information)
+*/
+typedef struct LocVar {
+  TString *varname;
+  int startpc;  /* first point where variable is active */
+  int endpc;    /* first point where variable is dead */
+} LocVar;
+
+
+/*
+** Associates the absolute line source for a given instruction ('pc').
+** The array 'lineinfo' gives, for each instruction, the difference in
+** lines from the previous instruction. When that difference does not
+** fit into a byte, Lua saves the absolute line for that instruction.
+** (Lua also saves the absolute line periodically, to speed up the
+** computation of a line number: we can use binary search in the
+** absolute-line array, but we must traverse the 'lineinfo' array
+** linearly to compute a line.)
+*/
+typedef struct AbsLineInfo {
+  int pc;
+  int line;
+} AbsLineInfo;
+
+/*
+** Function Prototypes
+*/
+typedef struct Proto {
+  CommonHeader;
+  lu_byte numparams;  /* number of fixed (named) parameters */
+  lu_byte is_vararg;
+  lu_byte maxstacksize;  /* number of registers needed by this function */
+  int sizeupvalues;  /* size of 'upvalues' */
+  int sizek;  /* size of 'k' */
+  int sizecode;
+  int sizelineinfo;
+  int sizep;  /* size of 'p' */
+  int sizelocvars;
+  int sizeabslineinfo;  /* size of 'abslineinfo' */
+  int linedefined;  /* debug information  */
+  int lastlinedefined;  /* debug information  */
+  TValue *k;  /* constants used by the function */
+  Instruction *code;  /* opcodes */
+  struct Proto **p;  /* functions defined inside the function */
+  Upvaldesc *upvalues;  /* upvalue information */
+  ls_byte *lineinfo;  /* information about source lines (debug information) */
+  AbsLineInfo *abslineinfo;  /* idem */
+  LocVar *locvars;  /* information about local variables (debug information) */
+  TString  *source;  /* used for debug information */
+  GCObject *gclist;
+} Proto;
+
+/* }================================================================== */
+
+
+/*
+** {==================================================================
+** Closures
+** ===================================================================
+*/
+
+#define LUA_VUPVAL	makevariant(LUA_TUPVAL, 0)
+
+
+/* Variant tags for functions */
+#define LUA_VLCL	makevariant(LUA_TFUNCTION, 0)  /* Lua closure */
+#define LUA_VLCF	makevariant(LUA_TFUNCTION, 1)  /* light C function */
+#define LUA_VCCL	makevariant(LUA_TFUNCTION, 2)  /* C closure */
+
+#define ttisfunction(o)		checktype(o, LUA_TFUNCTION)
+#define ttisclosure(o)		((rawtt(o) & 0x1F) == LUA_VLCL)
+#define ttisLclosure(o)		checktag((o), ctb(LUA_VLCL))
+#define ttislcf(o)		checktag((o), LUA_VLCF)
+#define ttisCclosure(o)		checktag((o), ctb(LUA_VCCL))
+
+#define isLfunction(o)	ttisLclosure(o)
+
+#define clvalue(o)	check_exp(ttisclosure(o), gco2cl(val_(o).gc))
+#define clLvalue(o)	check_exp(ttisLclosure(o), gco2lcl(val_(o).gc))
+#define fvalue(o)	check_exp(ttislcf(o), val_(o).f)
+#define clCvalue(o)	check_exp(ttisCclosure(o), gco2ccl(val_(o).gc))
+
+#define fvalueraw(v)	((v).f)
+
+#define setclLvalue(L,obj,x) \
+  { TValue *io = (obj); LClosure *x_ = (x); \
+    val_(io).gc = obj2gco(x_); settt_(io, ctb(LUA_VLCL)); \
+    checkliveness(L,io); }
+
+#define setclLvalue2s(L,o,cl)	setclLvalue(L,s2v(o),cl)
+
+#define setfvalue(obj,x) \
+  { TValue *io=(obj); val_(io).f=(x); settt_(io, LUA_VLCF); }
+
+#define setclCvalue(L,obj,x) \
+  { TValue *io = (obj); CClosure *x_ = (x); \
+    val_(io).gc = obj2gco(x_); settt_(io, ctb(LUA_VCCL)); \
+    checkliveness(L,io); }
+
+
+/*
+** Upvalues for Lua closures
+*/
+typedef struct UpVal {
+  CommonHeader;
+  lu_byte tbc;  /* true if it represents a to-be-closed variable */
+  TValue *v;  /* points to stack or to its own value */
+  union {
+    struct {  /* (when open) */
+      struct UpVal *next;  /* linked list */
+      struct UpVal **previous;
+    } open;
+    TValue value;  /* the value (when closed) */
+  } u;
+} UpVal;
+
+
+
+#define ClosureHeader \
+	CommonHeader; lu_byte nupvalues; GCObject *gclist
+
+typedef struct CClosure {
+  ClosureHeader;
+  lua_CFunction f;
+  TValue upvalue[1];  /* list of upvalues */
+} CClosure;
+
+
+typedef struct LClosure {
+  ClosureHeader;
+  struct Proto *p;
+  UpVal *upvals[1];  /* list of upvalues */
+} LClosure;
+
+
+typedef union Closure {
+  CClosure c;
+  LClosure l;
+} Closure;
+
+
+#define getproto(o)	(clLvalue(o)->p)
+
+/* }================================================================== */
+
+
+/*
+** {==================================================================
+** Tables
+** ===================================================================
+*/
+
+#define LUA_VTABLE	makevariant(LUA_TTABLE, 0)
+
+#define ttistable(o)		checktag((o), ctb(LUA_VTABLE))
+
+#define hvalue(o)	check_exp(ttistable(o), gco2t(val_(o).gc))
+
+#define sethvalue(L,obj,x) \
+  { TValue *io = (obj); Table *x_ = (x); \
+    val_(io).gc = obj2gco(x_); settt_(io, ctb(LUA_VTABLE)); \
+    checkliveness(L,io); }
+
+#define sethvalue2s(L,o,h)	sethvalue(L,s2v(o),h)
+
+
+/*
+** Nodes for Hash tables: A pack of two TValue's (key-value pairs)
+** plus a 'next' field to link colliding entries. The distribution
+** of the key's fields ('key_tt' and 'key_val') not forming a proper
+** 'TValue' allows for a smaller size for 'Node' both in 4-byte
+** and 8-byte alignments.
+*/
+typedef union Node {
+  struct NodeKey {
+    TValuefields;  /* fields for value */
+    lu_byte key_tt;  /* key type */
+    int next;  /* for chaining */
+    Value key_val;  /* key value */
+  } u;
+  TValue i_val;  /* direct access to node's value as a proper 'TValue' */
+} Node;
+
+
+/* copy a value into a key */
+#define setnodekey(L,node,obj) \
+	{ Node *n_=(node); const TValue *io_=(obj); \
+	  n_->u.key_val = io_->value_; n_->u.key_tt = io_->tt_; \
+	  checkliveness(L,io_); }
+
+
+/* copy a value from a key */
+#define getnodekey(L,obj,node) \
+	{ TValue *io_=(obj); const Node *n_=(node); \
+	  io_->value_ = n_->u.key_val; io_->tt_ = n_->u.key_tt; \
+	  checkliveness(L,io_); }
+
+
+/*
+** About 'alimit': if 'isrealasize(t)' is true, then 'alimit' is the
+** real size of 'array'. Otherwise, the real size of 'array' is the
+** smallest power of two not smaller than 'alimit' (or zero iff 'alimit'
+** is zero); 'alimit' is then used as a hint for #t.
+*/
+
+#define BITRAS		(1 << 7)
+#define isrealasize(t)		(!((t)->marked & BITRAS))
+#define setrealasize(t)		((t)->marked &= cast_byte(~BITRAS))
+#define setnorealasize(t)	((t)->marked |= BITRAS)
+
+
+typedef struct Table {
+  CommonHeader;
+  lu_byte flags;  /* 1<<p means tagmethod(p) is not present */
+  lu_byte lsizenode;  /* log2 of size of 'node' array */
+  unsigned int alimit;  /* "limit" of 'array' array */
+  TValue *array;  /* array part */
+  Node *node;
+  Node *lastfree;  /* any free position is before this position */
+  struct Table *metatable;
+  GCObject *gclist;
+} Table;
+
+
+/*
+** Macros to manipulate keys inserted in nodes
+*/
+#define keytt(node)		((node)->u.key_tt)
+#define keyval(node)		((node)->u.key_val)
+
+#define keyisnil(node)		(keytt(node) == LUA_TNIL)
+#define keyisinteger(node)	(keytt(node) == LUA_VNUMINT)
+#define keyival(node)		(keyval(node).i)
+#define keyisshrstr(node)	(keytt(node) == ctb(LUA_VSHRSTR))
+#define keystrval(node)		(gco2ts(keyval(node).gc))
+
+#define setnilkey(node)		(keytt(node) = LUA_TNIL)
+
+#define keyiscollectable(n)	(keytt(n) & BIT_ISCOLLECTABLE)
+
+#define gckey(n)	(keyval(n).gc)
+#define gckeyN(n)	(keyiscollectable(n) ? gckey(n) : NULL)
+
+
+/*
+** Use a "nil table" to mark dead keys in a table. Those keys serve
+** to keep space for removed entries, which may still be part of
+** chains. Note that the 'keytt' does not have the BIT_ISCOLLECTABLE
+** set, so these values are considered not collectable and are different
+** from any valid value.
+*/
+#define setdeadkey(n)	(keytt(n) = LUA_TTABLE, gckey(n) = NULL)
+
+/* }================================================================== */
+
+
+
+/*
+** 'module' operation for hashing (size is always a power of 2)
+*/
+#define lmod(s,size) \
+	(check_exp((size&(size-1))==0, (cast_int((s) & ((size)-1)))))
+
+
+#define twoto(x)	(1<<(x))
+#define sizenode(t)	(twoto((t)->lsizenode))
+
+
+/* size of buffer for 'luaO_utf8esc' function */
+#define UTF8BUFFSZ	8
+
+LUAI_FUNC int luaO_utf8esc (char *buff, unsigned long x);
+LUAI_FUNC int luaO_ceillog2 (unsigned int x);
+LUAI_FUNC int luaO_rawarith (lua_State *L, int op, const TValue *p1,
+                             const TValue *p2, TValue *res);
+LUAI_FUNC void luaO_arith (lua_State *L, int op, const TValue *p1,
+                           const TValue *p2, StkId res);
+LUAI_FUNC size_t luaO_str2num (const char *s, TValue *o);
+LUAI_FUNC int luaO_hexavalue (int c);
+LUAI_FUNC void luaO_tostring (lua_State *L, TValue *obj);
+LUAI_FUNC const char *luaO_pushvfstring (lua_State *L, const char *fmt,
+                                                       va_list argp);
+LUAI_FUNC const char *luaO_pushfstring (lua_State *L, const char *fmt, ...);
+LUAI_FUNC void luaO_chunkid (char *out, const char *source, size_t srclen);
+
+
+#endif
+
diff --git a/test/external/lua-5.4.0/src/lopcodes.c b/test/external/lua-5.4.0/src/lopcodes.c
new file mode 100644
index 0000000..c67aa22
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lopcodes.c
@@ -0,0 +1,104 @@
+/*
+** $Id: lopcodes.c $
+** Opcodes for Lua virtual machine
+** See Copyright Notice in lua.h
+*/
+
+#define lopcodes_c
+#define LUA_CORE
+
+#include "lprefix.h"
+
+
+#include "lopcodes.h"
+
+
+/* ORDER OP */
+
+LUAI_DDEF const lu_byte luaP_opmodes[NUM_OPCODES] = {
+/*       MM OT IT T  A  mode		   opcode  */
+  opmode(0, 0, 0, 0, 1, iABC)		/* OP_MOVE */
+ ,opmode(0, 0, 0, 0, 1, iAsBx)		/* OP_LOADI */
+ ,opmode(0, 0, 0, 0, 1, iAsBx)		/* OP_LOADF */
+ ,opmode(0, 0, 0, 0, 1, iABx)		/* OP_LOADK */
+ ,opmode(0, 0, 0, 0, 1, iABx)		/* OP_LOADKX */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_LOADFALSE */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_LFALSESKIP */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_LOADTRUE */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_LOADNIL */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_GETUPVAL */
+ ,opmode(0, 0, 0, 0, 0, iABC)		/* OP_SETUPVAL */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_GETTABUP */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_GETTABLE */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_GETI */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_GETFIELD */
+ ,opmode(0, 0, 0, 0, 0, iABC)		/* OP_SETTABUP */
+ ,opmode(0, 0, 0, 0, 0, iABC)		/* OP_SETTABLE */
+ ,opmode(0, 0, 0, 0, 0, iABC)		/* OP_SETI */
+ ,opmode(0, 0, 0, 0, 0, iABC)		/* OP_SETFIELD */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_NEWTABLE */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_SELF */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_ADDI */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_ADDK */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_SUBK */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_MULK */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_MODK */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_POWK */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_DIVK */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_IDIVK */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_BANDK */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_BORK */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_BXORK */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_SHRI */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_SHLI */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_ADD */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_SUB */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_MUL */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_MOD */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_POW */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_DIV */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_IDIV */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_BAND */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_BOR */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_BXOR */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_SHL */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_SHR */
+ ,opmode(1, 0, 0, 0, 0, iABC)		/* OP_MMBIN */
+ ,opmode(1, 0, 0, 0, 0, iABC)		/* OP_MMBINI*/
+ ,opmode(1, 0, 0, 0, 0, iABC)		/* OP_MMBINK*/
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_UNM */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_BNOT */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_NOT */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_LEN */
+ ,opmode(0, 0, 0, 0, 1, iABC)		/* OP_CONCAT */
+ ,opmode(0, 0, 0, 0, 0, iABC)		/* OP_CLOSE */
+ ,opmode(0, 0, 0, 0, 0, iABC)		/* OP_TBC */
+ ,opmode(0, 0, 0, 0, 0, isJ)		/* OP_JMP */
+ ,opmode(0, 0, 0, 1, 0, iABC)		/* OP_EQ */
+ ,opmode(0, 0, 0, 1, 0, iABC)		/* OP_LT */
+ ,opmode(0, 0, 0, 1, 0, iABC)		/* OP_LE */
+ ,opmode(0, 0, 0, 1, 0, iABC)		/* OP_EQK */
+ ,opmode(0, 0, 0, 1, 0, iABC)		/* OP_EQI */
+ ,opmode(0, 0, 0, 1, 0, iABC)		/* OP_LTI */
+ ,opmode(0, 0, 0, 1, 0, iABC)		/* OP_LEI */
+ ,opmode(0, 0, 0, 1, 0, iABC)		/* OP_GTI */
+ ,opmode(0, 0, 0, 1, 0, iABC)		/* OP_GEI */
+ ,opmode(0, 0, 0, 1, 0, iABC)		/* OP_TEST */
+ ,opmode(0, 0, 0, 1, 1, iABC)		/* OP_TESTSET */
+ ,opmode(0, 1, 1, 0, 1, iABC)		/* OP_CALL */
+ ,opmode(0, 1, 1, 0, 1, iABC)		/* OP_TAILCALL */
+ ,opmode(0, 0, 1, 0, 0, iABC)		/* OP_RETURN */
+ ,opmode(0, 0, 0, 0, 0, iABC)		/* OP_RETURN0 */
+ ,opmode(0, 0, 0, 0, 0, iABC)		/* OP_RETURN1 */
+ ,opmode(0, 0, 0, 0, 1, iABx)		/* OP_FORLOOP */
+ ,opmode(0, 0, 0, 0, 1, iABx)		/* OP_FORPREP */
+ ,opmode(0, 0, 0, 0, 0, iABx)		/* OP_TFORPREP */
+ ,opmode(0, 0, 0, 0, 0, iABC)		/* OP_TFORCALL */
+ ,opmode(0, 0, 0, 0, 1, iABx)		/* OP_TFORLOOP */
+ ,opmode(0, 0, 1, 0, 0, iABC)		/* OP_SETLIST */
+ ,opmode(0, 0, 0, 0, 1, iABx)		/* OP_CLOSURE */
+ ,opmode(0, 1, 0, 0, 1, iABC)		/* OP_VARARG */
+ ,opmode(0, 0, 1, 0, 1, iABC)		/* OP_VARARGPREP */
+ ,opmode(0, 0, 0, 0, 0, iAx)		/* OP_EXTRAARG */
+};
+
diff --git a/test/external/lua-5.4.0/src/lopcodes.h b/test/external/lua-5.4.0/src/lopcodes.h
new file mode 100644
index 0000000..122e5d2
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lopcodes.h
@@ -0,0 +1,392 @@
+/*
+** $Id: lopcodes.h $
+** Opcodes for Lua virtual machine
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lopcodes_h
+#define lopcodes_h
+
+#include "llimits.h"
+
+
+/*===========================================================================
+  We assume that instructions are unsigned 32-bit integers.
+  All instructions have an opcode in the first 7 bits.
+  Instructions can have the following formats:
+
+        3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0
+        1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
+iABC          C(8)     |      B(8)     |k|     A(8)      |   Op(7)     |
+iABx                Bx(17)               |     A(8)      |   Op(7)     |
+iAsBx              sBx (signed)(17)      |     A(8)      |   Op(7)     |
+iAx                           Ax(25)                     |   Op(7)     |
+isJ                           sJ(25)                     |   Op(7)     |
+
+  A signed argument is represented in excess K: the represented value is
+  the written unsigned value minus K, where K is half the maximum for the
+  corresponding unsigned argument.
+===========================================================================*/
+
+
+enum OpMode {iABC, iABx, iAsBx, iAx, isJ};  /* basic instruction formats */
+
+
+/*
+** size and position of opcode arguments.
+*/
+#define SIZE_C		8
+#define SIZE_B		8
+#define SIZE_Bx		(SIZE_C + SIZE_B + 1)
+#define SIZE_A		8
+#define SIZE_Ax		(SIZE_Bx + SIZE_A)
+#define SIZE_sJ		(SIZE_Bx + SIZE_A)
+
+#define SIZE_OP		7
+
+#define POS_OP		0
+
+#define POS_A		(POS_OP + SIZE_OP)
+#define POS_k		(POS_A + SIZE_A)
+#define POS_B		(POS_k + 1)
+#define POS_C		(POS_B + SIZE_B)
+
+#define POS_Bx		POS_k
+
+#define POS_Ax		POS_A
+
+#define POS_sJ		POS_A
+
+
+/*
+** limits for opcode arguments.
+** we use (signed) 'int' to manipulate most arguments,
+** so they must fit in ints.
+*/
+
+/* Check whether type 'int' has at least 'b' bits ('b' < 32) */
+#define L_INTHASBITS(b)		((UINT_MAX >> ((b) - 1)) >= 1)
+
+
+#if L_INTHASBITS(SIZE_Bx)
+#define MAXARG_Bx	((1<<SIZE_Bx)-1)
+#else
+#define MAXARG_Bx	MAX_INT
+#endif
+
+#define OFFSET_sBx	(MAXARG_Bx>>1)         /* 'sBx' is signed */
+
+
+#if L_INTHASBITS(SIZE_Ax)
+#define MAXARG_Ax	((1<<SIZE_Ax)-1)
+#else
+#define MAXARG_Ax	MAX_INT
+#endif
+
+#if L_INTHASBITS(SIZE_sJ)
+#define MAXARG_sJ	((1 << SIZE_sJ) - 1)
+#else
+#define MAXARG_sJ	MAX_INT
+#endif
+
+#define OFFSET_sJ	(MAXARG_sJ >> 1)
+
+
+#define MAXARG_A	((1<<SIZE_A)-1)
+#define MAXARG_B	((1<<SIZE_B)-1)
+#define MAXARG_C	((1<<SIZE_C)-1)
+#define OFFSET_sC	(MAXARG_C >> 1)
+
+#define int2sC(i)	((i) + OFFSET_sC)
+#define sC2int(i)	((i) - OFFSET_sC)
+
+
+/* creates a mask with 'n' 1 bits at position 'p' */
+#define MASK1(n,p)	((~((~(Instruction)0)<<(n)))<<(p))
+
+/* creates a mask with 'n' 0 bits at position 'p' */
+#define MASK0(n,p)	(~MASK1(n,p))
+
+/*
+** the following macros help to manipulate instructions
+*/
+
+#define GET_OPCODE(i)	(cast(OpCode, ((i)>>POS_OP) & MASK1(SIZE_OP,0)))
+#define SET_OPCODE(i,o)	((i) = (((i)&MASK0(SIZE_OP,POS_OP)) | \
+		((cast(Instruction, o)<<POS_OP)&MASK1(SIZE_OP,POS_OP))))
+
+#define checkopm(i,m)	(getOpMode(GET_OPCODE(i)) == m)
+
+
+#define getarg(i,pos,size)	(cast_int(((i)>>(pos)) & MASK1(size,0)))
+#define setarg(i,v,pos,size)	((i) = (((i)&MASK0(size,pos)) | \
+                ((cast(Instruction, v)<<pos)&MASK1(size,pos))))
+
+#define GETARG_A(i)	getarg(i, POS_A, SIZE_A)
+#define SETARG_A(i,v)	setarg(i, v, POS_A, SIZE_A)
+
+#define GETARG_B(i)	check_exp(checkopm(i, iABC), getarg(i, POS_B, SIZE_B))
+#define GETARG_sB(i)	sC2int(GETARG_B(i))
+#define SETARG_B(i,v)	setarg(i, v, POS_B, SIZE_B)
+
+#define GETARG_C(i)	check_exp(checkopm(i, iABC), getarg(i, POS_C, SIZE_C))
+#define GETARG_sC(i)	sC2int(GETARG_C(i))
+#define SETARG_C(i,v)	setarg(i, v, POS_C, SIZE_C)
+
+#define TESTARG_k(i)	check_exp(checkopm(i, iABC), (cast_int(((i) & (1u << POS_k)))))
+#define GETARG_k(i)	check_exp(checkopm(i, iABC), getarg(i, POS_k, 1))
+#define SETARG_k(i,v)	setarg(i, v, POS_k, 1)
+
+#define GETARG_Bx(i)	check_exp(checkopm(i, iABx), getarg(i, POS_Bx, SIZE_Bx))
+#define SETARG_Bx(i,v)	setarg(i, v, POS_Bx, SIZE_Bx)
+
+#define GETARG_Ax(i)	check_exp(checkopm(i, iAx), getarg(i, POS_Ax, SIZE_Ax))
+#define SETARG_Ax(i,v)	setarg(i, v, POS_Ax, SIZE_Ax)
+
+#define GETARG_sBx(i)  \
+	check_exp(checkopm(i, iAsBx), getarg(i, POS_Bx, SIZE_Bx) - OFFSET_sBx)
+#define SETARG_sBx(i,b)	SETARG_Bx((i),cast_uint((b)+OFFSET_sBx))
+
+#define GETARG_sJ(i)  \
+	check_exp(checkopm(i, isJ), getarg(i, POS_sJ, SIZE_sJ) - OFFSET_sJ)
+#define SETARG_sJ(i,j) \
+	setarg(i, cast_uint((j)+OFFSET_sJ), POS_sJ, SIZE_sJ)
+
+
+#define CREATE_ABCk(o,a,b,c,k)	((cast(Instruction, o)<<POS_OP) \
+			| (cast(Instruction, a)<<POS_A) \
+			| (cast(Instruction, b)<<POS_B) \
+			| (cast(Instruction, c)<<POS_C) \
+			| (cast(Instruction, k)<<POS_k))
+
+#define CREATE_ABx(o,a,bc)	((cast(Instruction, o)<<POS_OP) \
+			| (cast(Instruction, a)<<POS_A) \
+			| (cast(Instruction, bc)<<POS_Bx))
+
+#define CREATE_Ax(o,a)		((cast(Instruction, o)<<POS_OP) \
+			| (cast(Instruction, a)<<POS_Ax))
+
+#define CREATE_sJ(o,j,k)	((cast(Instruction, o) << POS_OP) \
+			| (cast(Instruction, j) << POS_sJ) \
+			| (cast(Instruction, k) << POS_k))
+
+
+#if !defined(MAXINDEXRK)  /* (for debugging only) */
+#define MAXINDEXRK	MAXARG_B
+#endif
+
+
+/*
+** invalid register that fits in 8 bits
+*/
+#define NO_REG		MAXARG_A
+
+
+/*
+** R[x] - register
+** K[x] - constant (in constant table)
+** RK(x) == if k(i) then K[x] else R[x]
+*/
+
+
+/*
+** grep "ORDER OP" if you change these enums
+*/
+
+typedef enum {
+/*----------------------------------------------------------------------
+  name		args	description
+------------------------------------------------------------------------*/
+OP_MOVE,/*	A B	R[A] := R[B]					*/
+OP_LOADI,/*	A sBx	R[A] := sBx					*/
+OP_LOADF,/*	A sBx	R[A] := (lua_Number)sBx				*/
+OP_LOADK,/*	A Bx	R[A] := K[Bx]					*/
+OP_LOADKX,/*	A	R[A] := K[extra arg]				*/
+OP_LOADFALSE,/*	A	R[A] := false					*/
+OP_LFALSESKIP,/*A	R[A] := false; pc++				*/
+OP_LOADTRUE,/*	A	R[A] := true					*/
+OP_LOADNIL,/*	A B	R[A], R[A+1], ..., R[A+B] := nil		*/
+OP_GETUPVAL,/*	A B	R[A] := UpValue[B]				*/
+OP_SETUPVAL,/*	A B	UpValue[B] := R[A]				*/
+
+OP_GETTABUP,/*	A B C	R[A] := UpValue[B][K[C]:string]			*/
+OP_GETTABLE,/*	A B C	R[A] := R[B][R[C]]				*/
+OP_GETI,/*	A B C	R[A] := R[B][C]					*/
+OP_GETFIELD,/*	A B C	R[A] := R[B][K[C]:string]			*/
+
+OP_SETTABUP,/*	A B C	UpValue[A][K[B]:string] := RK(C)		*/
+OP_SETTABLE,/*	A B C	R[A][R[B]] := RK(C)				*/
+OP_SETI,/*	A B C	R[A][B] := RK(C)				*/
+OP_SETFIELD,/*	A B C	R[A][K[B]:string] := RK(C)			*/
+
+OP_NEWTABLE,/*	A B C k	R[A] := {}					*/
+
+OP_SELF,/*	A B C	R[A+1] := R[B]; R[A] := R[B][RK(C):string]	*/
+
+OP_ADDI,/*	A B sC	R[A] := R[B] + sC				*/
+
+OP_ADDK,/*	A B C	R[A] := R[B] + K[C]				*/
+OP_SUBK,/*	A B C	R[A] := R[B] - K[C]				*/
+OP_MULK,/*	A B C	R[A] := R[B] * K[C]				*/
+OP_MODK,/*	A B C	R[A] := R[B] % K[C]				*/
+OP_POWK,/*	A B C	R[A] := R[B] ^ K[C]				*/
+OP_DIVK,/*	A B C	R[A] := R[B] / K[C]				*/
+OP_IDIVK,/*	A B C	R[A] := R[B] // K[C]				*/
+
+OP_BANDK,/*	A B C	R[A] := R[B] & K[C]:integer			*/
+OP_BORK,/*	A B C	R[A] := R[B] | K[C]:integer			*/
+OP_BXORK,/*	A B C	R[A] := R[B] ~ K[C]:integer			*/
+
+OP_SHRI,/*	A B sC	R[A] := R[B] >> sC				*/
+OP_SHLI,/*	A B sC	R[A] := sC << R[B]				*/
+
+OP_ADD,/*	A B C	R[A] := R[B] + R[C]				*/
+OP_SUB,/*	A B C	R[A] := R[B] - R[C]				*/
+OP_MUL,/*	A B C	R[A] := R[B] * R[C]				*/
+OP_MOD,/*	A B C	R[A] := R[B] % R[C]				*/
+OP_POW,/*	A B C	R[A] := R[B] ^ R[C]				*/
+OP_DIV,/*	A B C	R[A] := R[B] / R[C]				*/
+OP_IDIV,/*	A B C	R[A] := R[B] // R[C]				*/
+
+OP_BAND,/*	A B C	R[A] := R[B] & R[C]				*/
+OP_BOR,/*	A B C	R[A] := R[B] | R[C]				*/
+OP_BXOR,/*	A B C	R[A] := R[B] ~ R[C]				*/
+OP_SHL,/*	A B C	R[A] := R[B] << R[C]				*/
+OP_SHR,/*	A B C	R[A] := R[B] >> R[C]				*/
+
+OP_MMBIN,/*	A B C	call C metamethod over R[A] and R[B]		*/
+OP_MMBINI,/*	A sB C k	call C metamethod over R[A] and sB	*/
+OP_MMBINK,/*	A B C k		call C metamethod over R[A] and K[B]	*/
+
+OP_UNM,/*	A B	R[A] := -R[B]					*/
+OP_BNOT,/*	A B	R[A] := ~R[B]					*/
+OP_NOT,/*	A B	R[A] := not R[B]				*/
+OP_LEN,/*	A B	R[A] := length of R[B]				*/
+
+OP_CONCAT,/*	A B	R[A] := R[A].. ... ..R[A + B - 1]		*/
+
+OP_CLOSE,/*	A	close all upvalues >= R[A]			*/
+OP_TBC,/*	A	mark variable A "to be closed"			*/
+OP_JMP,/*	sJ	pc += sJ					*/
+OP_EQ,/*	A B k	if ((R[A] == R[B]) ~= k) then pc++		*/
+OP_LT,/*	A B k	if ((R[A] <  R[B]) ~= k) then pc++		*/
+OP_LE,/*	A B k	if ((R[A] <= R[B]) ~= k) then pc++		*/
+
+OP_EQK,/*	A B k	if ((R[A] == K[B]) ~= k) then pc++		*/
+OP_EQI,/*	A sB k	if ((R[A] == sB) ~= k) then pc++		*/
+OP_LTI,/*	A sB k	if ((R[A] < sB) ~= k) then pc++			*/
+OP_LEI,/*	A sB k	if ((R[A] <= sB) ~= k) then pc++		*/
+OP_GTI,/*	A sB k	if ((R[A] > sB) ~= k) then pc++			*/
+OP_GEI,/*	A sB k	if ((R[A] >= sB) ~= k) then pc++		*/
+
+OP_TEST,/*	A k	if (not R[A] == k) then pc++			*/
+OP_TESTSET,/*	A B k	if (not R[B] == k) then pc++ else R[A] := R[B]	*/
+
+OP_CALL,/*	A B C	R[A], ... ,R[A+C-2] := R[A](R[A+1], ... ,R[A+B-1]) */
+OP_TAILCALL,/*	A B C k	return R[A](R[A+1], ... ,R[A+B-1])		*/
+
+OP_RETURN,/*	A B C k	return R[A], ... ,R[A+B-2]	(see note)	*/
+OP_RETURN0,/*		return						*/
+OP_RETURN1,/*	A	return R[A]					*/
+
+OP_FORLOOP,/*	A Bx	update counters; if loop continues then pc-=Bx; */
+OP_FORPREP,/*	A Bx	<check values and prepare counters>;
+                        if not to run then pc+=Bx+1;			*/
+
+OP_TFORPREP,/*	A Bx	create upvalue for R[A + 3]; pc+=Bx		*/
+OP_TFORCALL,/*	A C	R[A+4], ... ,R[A+3+C] := R[A](R[A+1], R[A+2]);	*/
+OP_TFORLOOP,/*	A Bx	if R[A+2] ~= nil then { R[A]=R[A+2]; pc -= Bx }	*/
+
+OP_SETLIST,/*	A B C k	R[A][(C-1)*FPF+i] := R[A+i], 1 <= i <= B	*/
+
+OP_CLOSURE,/*	A Bx	R[A] := closure(KPROTO[Bx])			*/
+
+OP_VARARG,/*	A C	R[A], R[A+1], ..., R[A+C-2] = vararg		*/
+
+OP_VARARGPREP,/*A	(adjust vararg parameters)			*/
+
+OP_EXTRAARG/*	Ax	extra (larger) argument for previous opcode	*/
+} OpCode;
+
+
+#define NUM_OPCODES	((int)(OP_EXTRAARG) + 1)
+
+
+
+/*===========================================================================
+  Notes:
+  (*) In OP_CALL, if (B == 0) then B = top - A. If (C == 0), then
+  'top' is set to last_result+1, so next open instruction (OP_CALL,
+  OP_RETURN*, OP_SETLIST) may use 'top'.
+
+  (*) In OP_VARARG, if (C == 0) then use actual number of varargs and
+  set top (like in OP_CALL with C == 0).
+
+  (*) In OP_RETURN, if (B == 0) then return up to 'top'.
+
+  (*) In OP_LOADKX and OP_NEWTABLE, the next instruction is always
+  OP_EXTRAARG.
+
+  (*) In OP_SETLIST, if (B == 0) then real B = 'top'; if k, then
+  real C = EXTRAARG _ C (the bits of EXTRAARG concatenated with the
+  bits of C).
+
+  (*) In OP_NEWTABLE, B is log2 of the hash size (which is always a
+  power of 2) plus 1, or zero for size zero. If not k, the array size
+  is C. Otherwise, the array size is EXTRAARG _ C.
+
+  (*) For comparisons, k specifies what condition the test should accept
+  (true or false).
+
+  (*) In OP_MMBINI/OP_MMBINK, k means the arguments were flipped
+   (the constant is the first operand).
+
+  (*) All 'skips' (pc++) assume that next instruction is a jump.
+
+  (*) In instructions OP_RETURN/OP_TAILCALL, 'k' specifies that the
+  function builds upvalues, which may need to be closed. C > 0 means
+  the function is vararg, so that its 'func' must be corrected before
+  returning; in this case, (C - 1) is its number of fixed parameters.
+
+  (*) In comparisons with an immediate operand, C signals whether the
+  original operand was a float. (It must be corrected in case of
+  metamethods.)
+
+===========================================================================*/
+
+
+/*
+** masks for instruction properties. The format is:
+** bits 0-2: op mode
+** bit 3: instruction set register A
+** bit 4: operator is a test (next instruction must be a jump)
+** bit 5: instruction uses 'L->top' set by previous instruction (when B == 0)
+** bit 6: instruction sets 'L->top' for next instruction (when C == 0)
+** bit 7: instruction is an MM instruction (call a metamethod)
+*/
+
+LUAI_DDEC(const lu_byte luaP_opmodes[NUM_OPCODES];)
+
+#define getOpMode(m)	(cast(enum OpMode, luaP_opmodes[m] & 7))
+#define testAMode(m)	(luaP_opmodes[m] & (1 << 3))
+#define testTMode(m)	(luaP_opmodes[m] & (1 << 4))
+#define testITMode(m)	(luaP_opmodes[m] & (1 << 5))
+#define testOTMode(m)	(luaP_opmodes[m] & (1 << 6))
+#define testMMMode(m)	(luaP_opmodes[m] & (1 << 7))
+
+/* "out top" (set top for next instruction) */
+#define isOT(i)  \
+	((testOTMode(GET_OPCODE(i)) && GETARG_C(i) == 0) || \
+          GET_OPCODE(i) == OP_TAILCALL)
+
+/* "in top" (uses top from previous instruction) */
+#define isIT(i)		(testITMode(GET_OPCODE(i)) && GETARG_B(i) == 0)
+
+#define opmode(mm,ot,it,t,a,m)  \
+    (((mm) << 7) | ((ot) << 6) | ((it) << 5) | ((t) << 4) | ((a) << 3) | (m))
+
+
+/* number of list items to accumulate before a SETLIST instruction */
+#define LFIELDS_PER_FLUSH	50
+
+#endif
diff --git a/test/external/lua-5.4.0/src/lopnames.h b/test/external/lua-5.4.0/src/lopnames.h
new file mode 100644
index 0000000..965cec9
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lopnames.h
@@ -0,0 +1,103 @@
+/*
+** $Id: lopnames.h $
+** Opcode names
+** See Copyright Notice in lua.h
+*/
+
+#if !defined(lopnames_h)
+#define lopnames_h
+
+#include <stddef.h>
+
+
+/* ORDER OP */
+
+static const char *const opnames[] = {
+  "MOVE",
+  "LOADI",
+  "LOADF",
+  "LOADK",
+  "LOADKX",
+  "LOADFALSE",
+  "LFALSESKIP",
+  "LOADTRUE",
+  "LOADNIL",
+  "GETUPVAL",
+  "SETUPVAL",
+  "GETTABUP",
+  "GETTABLE",
+  "GETI",
+  "GETFIELD",
+  "SETTABUP",
+  "SETTABLE",
+  "SETI",
+  "SETFIELD",
+  "NEWTABLE",
+  "SELF",
+  "ADDI",
+  "ADDK",
+  "SUBK",
+  "MULK",
+  "MODK",
+  "POWK",
+  "DIVK",
+  "IDIVK",
+  "BANDK",
+  "BORK",
+  "BXORK",
+  "SHRI",
+  "SHLI",
+  "ADD",
+  "SUB",
+  "MUL",
+  "MOD",
+  "POW",
+  "DIV",
+  "IDIV",
+  "BAND",
+  "BOR",
+  "BXOR",
+  "SHL",
+  "SHR",
+  "MMBIN",
+  "MMBINI",
+  "MMBINK",
+  "UNM",
+  "BNOT",
+  "NOT",
+  "LEN",
+  "CONCAT",
+  "CLOSE",
+  "TBC",
+  "JMP",
+  "EQ",
+  "LT",
+  "LE",
+  "EQK",
+  "EQI",
+  "LTI",
+  "LEI",
+  "GTI",
+  "GEI",
+  "TEST",
+  "TESTSET",
+  "CALL",
+  "TAILCALL",
+  "RETURN",
+  "RETURN0",
+  "RETURN1",
+  "FORLOOP",
+  "FORPREP",
+  "TFORPREP",
+  "TFORCALL",
+  "TFORLOOP",
+  "SETLIST",
+  "CLOSURE",
+  "VARARG",
+  "VARARGPREP",
+  "EXTRAARG",
+  NULL
+};
+
+#endif
+
diff --git a/test/external/lua-5.4.0/src/loslib.c b/test/external/lua-5.4.0/src/loslib.c
new file mode 100644
index 0000000..e65e188
--- /dev/null
+++ b/test/external/lua-5.4.0/src/loslib.c
@@ -0,0 +1,430 @@
+/*
+** $Id: loslib.c $
+** Standard Operating System library
+** See Copyright Notice in lua.h
+*/
+
+#define loslib_c
+#define LUA_LIB
+
+#include "lprefix.h"
+
+
+#include <errno.h>
+#include <locale.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+/*
+** {==================================================================
+** List of valid conversion specifiers for the 'strftime' function;
+** options are grouped by length; group of length 2 start with '||'.
+** ===================================================================
+*/
+#if !defined(LUA_STRFTIMEOPTIONS)	/* { */
+
+/* options for ANSI C 89 (only 1-char options) */
+#define L_STRFTIMEC89		"aAbBcdHIjmMpSUwWxXyYZ%"
+
+/* options for ISO C 99 and POSIX */
+#define L_STRFTIMEC99 "aAbBcCdDeFgGhHIjmMnprRStTuUVwWxXyYzZ%" \
+    "||" "EcECExEXEyEY" "OdOeOHOIOmOMOSOuOUOVOwOWOy"  /* two-char options */
+
+/* options for Windows */
+#define L_STRFTIMEWIN "aAbBcdHIjmMpSUwWxXyYzZ%" \
+    "||" "#c#x#d#H#I#j#m#M#S#U#w#W#y#Y"  /* two-char options */
+
+#if defined(LUA_USE_WINDOWS)
+#define LUA_STRFTIMEOPTIONS	L_STRFTIMEWIN
+#elif defined(LUA_USE_C89)
+#define LUA_STRFTIMEOPTIONS	L_STRFTIMEC89
+#else  /* C99 specification */
+#define LUA_STRFTIMEOPTIONS	L_STRFTIMEC99
+#endif
+
+#endif					/* } */
+/* }================================================================== */
+
+
+/*
+** {==================================================================
+** Configuration for time-related stuff
+** ===================================================================
+*/
+
+/*
+** type to represent time_t in Lua
+*/
+#if !defined(LUA_NUMTIME)	/* { */
+
+#define l_timet			lua_Integer
+#define l_pushtime(L,t)		lua_pushinteger(L,(lua_Integer)(t))
+#define l_gettime(L,arg)	luaL_checkinteger(L, arg)
+
+#else				/* }{ */
+
+#define l_timet			lua_Number
+#define l_pushtime(L,t)		lua_pushnumber(L,(lua_Number)(t))
+#define l_gettime(L,arg)	luaL_checknumber(L, arg)
+
+#endif				/* } */
+
+
+#if !defined(l_gmtime)		/* { */
+/*
+** By default, Lua uses gmtime/localtime, except when POSIX is available,
+** where it uses gmtime_r/localtime_r
+*/
+
+#if defined(LUA_USE_POSIX)	/* { */
+
+#define l_gmtime(t,r)		gmtime_r(t,r)
+#define l_localtime(t,r)	localtime_r(t,r)
+
+#else				/* }{ */
+
+/* ISO C definitions */
+#define l_gmtime(t,r)		((void)(r)->tm_sec, gmtime(t))
+#define l_localtime(t,r)	((void)(r)->tm_sec, localtime(t))
+
+#endif				/* } */
+
+#endif				/* } */
+
+/* }================================================================== */
+
+
+/*
+** {==================================================================
+** Configuration for 'tmpnam':
+** By default, Lua uses tmpnam except when POSIX is available, where
+** it uses mkstemp.
+** ===================================================================
+*/
+#if !defined(lua_tmpnam)	/* { */
+
+#if defined(LUA_USE_POSIX)	/* { */
+
+#include <unistd.h>
+
+#define LUA_TMPNAMBUFSIZE	32
+
+#if !defined(LUA_TMPNAMTEMPLATE)
+#define LUA_TMPNAMTEMPLATE	"/tmp/lua_XXXXXX"
+#endif
+
+#define lua_tmpnam(b,e) { \
+        strcpy(b, LUA_TMPNAMTEMPLATE); \
+        e = mkstemp(b); \
+        if (e != -1) close(e); \
+        e = (e == -1); }
+
+#else				/* }{ */
+
+/* ISO C definitions */
+#define LUA_TMPNAMBUFSIZE	L_tmpnam
+#define lua_tmpnam(b,e)		{ e = (tmpnam(b) == NULL); }
+
+#endif				/* } */
+
+#endif				/* } */
+/* }================================================================== */
+
+
+
+static int os_execute (lua_State *L) {
+  const char *cmd = luaL_optstring(L, 1, NULL);
+  int stat;
+  errno = 0;
+  stat = system(cmd);
+  if (cmd != NULL)
+    return luaL_execresult(L, stat);
+  else {
+    lua_pushboolean(L, stat);  /* true if there is a shell */
+    return 1;
+  }
+}
+
+
+static int os_remove (lua_State *L) {
+  const char *filename = luaL_checkstring(L, 1);
+  return luaL_fileresult(L, remove(filename) == 0, filename);
+}
+
+
+static int os_rename (lua_State *L) {
+  const char *fromname = luaL_checkstring(L, 1);
+  const char *toname = luaL_checkstring(L, 2);
+  return luaL_fileresult(L, rename(fromname, toname) == 0, NULL);
+}
+
+
+static int os_tmpname (lua_State *L) {
+  char buff[LUA_TMPNAMBUFSIZE];
+  int err;
+  lua_tmpnam(buff, err);
+  if (err)
+    return luaL_error(L, "unable to generate a unique filename");
+  lua_pushstring(L, buff);
+  return 1;
+}
+
+
+static int os_getenv (lua_State *L) {
+  lua_pushstring(L, getenv(luaL_checkstring(L, 1)));  /* if NULL push nil */
+  return 1;
+}
+
+
+static int os_clock (lua_State *L) {
+  lua_pushnumber(L, ((lua_Number)clock())/(lua_Number)CLOCKS_PER_SEC);
+  return 1;
+}
+
+
+/*
+** {======================================================
+** Time/Date operations
+** { year=%Y, month=%m, day=%d, hour=%H, min=%M, sec=%S,
+**   wday=%w+1, yday=%j, isdst=? }
+** =======================================================
+*/
+
+/*
+** About the overflow check: an overflow cannot occur when time
+** is represented by a lua_Integer, because either lua_Integer is
+** large enough to represent all int fields or it is not large enough
+** to represent a time that cause a field to overflow.  However, if
+** times are represented as doubles and lua_Integer is int, then the
+** time 0x1.e1853b0d184f6p+55 would cause an overflow when adding 1900
+** to compute the year.
+*/
+static void setfield (lua_State *L, const char *key, int value, int delta) {
+  #if (defined(LUA_NUMTIME) && LUA_MAXINTEGER <= INT_MAX)
+    if (value > LUA_MAXINTEGER - delta)
+      luaL_error(L, "field '%s' is out-of-bound", key);
+  #endif
+  lua_pushinteger(L, (lua_Integer)value + delta);
+  lua_setfield(L, -2, key);
+}
+
+
+static void setboolfield (lua_State *L, const char *key, int value) {
+  if (value < 0)  /* undefined? */
+    return;  /* does not set field */
+  lua_pushboolean(L, value);
+  lua_setfield(L, -2, key);
+}
+
+
+/*
+** Set all fields from structure 'tm' in the table on top of the stack
+*/
+static void setallfields (lua_State *L, struct tm *stm) {
+  setfield(L, "year", stm->tm_year, 1900);
+  setfield(L, "month", stm->tm_mon, 1);
+  setfield(L, "day", stm->tm_mday, 0);
+  setfield(L, "hour", stm->tm_hour, 0);
+  setfield(L, "min", stm->tm_min, 0);
+  setfield(L, "sec", stm->tm_sec, 0);
+  setfield(L, "yday", stm->tm_yday, 1);
+  setfield(L, "wday", stm->tm_wday, 1);
+  setboolfield(L, "isdst", stm->tm_isdst);
+}
+
+
+static int getboolfield (lua_State *L, const char *key) {
+  int res;
+  res = (lua_getfield(L, -1, key) == LUA_TNIL) ? -1 : lua_toboolean(L, -1);
+  lua_pop(L, 1);
+  return res;
+}
+
+
+static int getfield (lua_State *L, const char *key, int d, int delta) {
+  int isnum;
+  int t = lua_getfield(L, -1, key);  /* get field and its type */
+  lua_Integer res = lua_tointegerx(L, -1, &isnum);
+  if (!isnum) {  /* field is not an integer? */
+    if (t != LUA_TNIL)  /* some other value? */
+      return luaL_error(L, "field '%s' is not an integer", key);
+    else if (d < 0)  /* absent field; no default? */
+      return luaL_error(L, "field '%s' missing in date table", key);
+    res = d;
+  }
+  else {
+    /* unsigned avoids overflow when lua_Integer has 32 bits */
+    if (!(res >= 0 ? (lua_Unsigned)res <= (lua_Unsigned)INT_MAX + delta
+                   : (lua_Integer)INT_MIN + delta <= res))
+      return luaL_error(L, "field '%s' is out-of-bound", key);
+    res -= delta;
+  }
+  lua_pop(L, 1);
+  return (int)res;
+}
+
+
+static const char *checkoption (lua_State *L, const char *conv,
+                                ptrdiff_t convlen, char *buff) {
+  const char *option = LUA_STRFTIMEOPTIONS;
+  int oplen = 1;  /* length of options being checked */
+  for (; *option != '\0' && oplen <= convlen; option += oplen) {
+    if (*option == '|')  /* next block? */
+      oplen++;  /* will check options with next length (+1) */
+    else if (memcmp(conv, option, oplen) == 0) {  /* match? */
+      memcpy(buff, conv, oplen);  /* copy valid option to buffer */
+      buff[oplen] = '\0';
+      return conv + oplen;  /* return next item */
+    }
+  }
+  luaL_argerror(L, 1,
+    lua_pushfstring(L, "invalid conversion specifier '%%%s'", conv));
+  return conv;  /* to avoid warnings */
+}
+
+
+static time_t l_checktime (lua_State *L, int arg) {
+  l_timet t = l_gettime(L, arg);
+  luaL_argcheck(L, (time_t)t == t, arg, "time out-of-bounds");
+  return (time_t)t;
+}
+
+
+/* maximum size for an individual 'strftime' item */
+#define SIZETIMEFMT	250
+
+
+static int os_date (lua_State *L) {
+  size_t slen;
+  const char *s = luaL_optlstring(L, 1, "%c", &slen);
+  time_t t = luaL_opt(L, l_checktime, 2, time(NULL));
+  const char *se = s + slen;  /* 's' end */
+  struct tm tmr, *stm;
+  if (*s == '!') {  /* UTC? */
+    stm = l_gmtime(&t, &tmr);
+    s++;  /* skip '!' */
+  }
+  else
+    stm = l_localtime(&t, &tmr);
+  if (stm == NULL)  /* invalid date? */
+    return luaL_error(L,
+                 "date result cannot be represented in this installation");
+  if (strcmp(s, "*t") == 0) {
+    lua_createtable(L, 0, 9);  /* 9 = number of fields */
+    setallfields(L, stm);
+  }
+  else {
+    char cc[4];  /* buffer for individual conversion specifiers */
+    luaL_Buffer b;
+    cc[0] = '%';
+    luaL_buffinit(L, &b);
+    while (s < se) {
+      if (*s != '%')  /* not a conversion specifier? */
+        luaL_addchar(&b, *s++);
+      else {
+        size_t reslen;
+        char *buff = luaL_prepbuffsize(&b, SIZETIMEFMT);
+        s++;  /* skip '%' */
+        s = checkoption(L, s, se - s, cc + 1);  /* copy specifier to 'cc' */
+        reslen = strftime(buff, SIZETIMEFMT, cc, stm);
+        luaL_addsize(&b, reslen);
+      }
+    }
+    luaL_pushresult(&b);
+  }
+  return 1;
+}
+
+
+static int os_time (lua_State *L) {
+  time_t t;
+  if (lua_isnoneornil(L, 1))  /* called without args? */
+    t = time(NULL);  /* get current time */
+  else {
+    struct tm ts;
+    luaL_checktype(L, 1, LUA_TTABLE);
+    lua_settop(L, 1);  /* make sure table is at the top */
+    ts.tm_year = getfield(L, "year", -1, 1900);
+    ts.tm_mon = getfield(L, "month", -1, 1);
+    ts.tm_mday = getfield(L, "day", -1, 0);
+    ts.tm_hour = getfield(L, "hour", 12, 0);
+    ts.tm_min = getfield(L, "min", 0, 0);
+    ts.tm_sec = getfield(L, "sec", 0, 0);
+    ts.tm_isdst = getboolfield(L, "isdst");
+    t = mktime(&ts);
+    setallfields(L, &ts);  /* update fields with normalized values */
+  }
+  if (t != (time_t)(l_timet)t || t == (time_t)(-1))
+    return luaL_error(L,
+                  "time result cannot be represented in this installation");
+  l_pushtime(L, t);
+  return 1;
+}
+
+
+static int os_difftime (lua_State *L) {
+  time_t t1 = l_checktime(L, 1);
+  time_t t2 = l_checktime(L, 2);
+  lua_pushnumber(L, (lua_Number)difftime(t1, t2));
+  return 1;
+}
+
+/* }====================================================== */
+
+
+static int os_setlocale (lua_State *L) {
+  static const int cat[] = {LC_ALL, LC_COLLATE, LC_CTYPE, LC_MONETARY,
+                      LC_NUMERIC, LC_TIME};
+  static const char *const catnames[] = {"all", "collate", "ctype", "monetary",
+     "numeric", "time", NULL};
+  const char *l = luaL_optstring(L, 1, NULL);
+  int op = luaL_checkoption(L, 2, "all", catnames);
+  lua_pushstring(L, setlocale(cat[op], l));
+  return 1;
+}
+
+
+static int os_exit (lua_State *L) {
+  int status;
+  if (lua_isboolean(L, 1))
+    status = (lua_toboolean(L, 1) ? EXIT_SUCCESS : EXIT_FAILURE);
+  else
+    status = (int)luaL_optinteger(L, 1, EXIT_SUCCESS);
+  if (lua_toboolean(L, 2))
+    lua_close(L);
+  if (L) exit(status);  /* 'if' to avoid warnings for unreachable 'return' */
+  return 0;
+}
+
+
+static const luaL_Reg syslib[] = {
+  {"clock",     os_clock},
+  {"date",      os_date},
+  {"difftime",  os_difftime},
+  {"execute",   os_execute},
+  {"exit",      os_exit},
+  {"getenv",    os_getenv},
+  {"remove",    os_remove},
+  {"rename",    os_rename},
+  {"setlocale", os_setlocale},
+  {"time",      os_time},
+  {"tmpname",   os_tmpname},
+  {NULL, NULL}
+};
+
+/* }====================================================== */
+
+
+
+LUAMOD_API int luaopen_os (lua_State *L) {
+  luaL_newlib(L, syslib);
+  return 1;
+}
+
diff --git a/test/external/lua-5.4.0/src/lparser.c b/test/external/lua-5.4.0/src/lparser.c
new file mode 100644
index 0000000..bc7d9a4
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lparser.c
@@ -0,0 +1,1996 @@
+/*
+** $Id: lparser.c $
+** Lua Parser
+** See Copyright Notice in lua.h
+*/
+
+#define lparser_c
+#define LUA_CORE
+
+#include "lprefix.h"
+
+
+#include <limits.h>
+#include <string.h>
+
+#include "lua.h"
+
+#include "lcode.h"
+#include "ldebug.h"
+#include "ldo.h"
+#include "lfunc.h"
+#include "llex.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lopcodes.h"
+#include "lparser.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+
+
+
+/* maximum number of local variables per function (must be smaller
+   than 250, due to the bytecode format) */
+#define MAXVARS		200
+
+
+#define hasmultret(k)		((k) == VCALL || (k) == VVARARG)
+
+
+/* because all strings are unified by the scanner, the parser
+   can use pointer equality for string equality */
+#define eqstr(a,b)	((a) == (b))
+
+
+/*
+** nodes for block list (list of active blocks)
+*/
+typedef struct BlockCnt {
+  struct BlockCnt *previous;  /* chain */
+  int firstlabel;  /* index of first label in this block */
+  int firstgoto;  /* index of first pending goto in this block */
+  lu_byte nactvar;  /* # active locals outside the block */
+  lu_byte upval;  /* true if some variable in the block is an upvalue */
+  lu_byte isloop;  /* true if 'block' is a loop */
+  lu_byte insidetbc;  /* true if inside the scope of a to-be-closed var. */
+} BlockCnt;
+
+
+
+/*
+** prototypes for recursive non-terminal functions
+*/
+static void statement (LexState *ls);
+static void expr (LexState *ls, expdesc *v);
+
+
+static l_noret error_expected (LexState *ls, int token) {
+  luaX_syntaxerror(ls,
+      luaO_pushfstring(ls->L, "%s expected", luaX_token2str(ls, token)));
+}
+
+
+static l_noret errorlimit (FuncState *fs, int limit, const char *what) {
+  lua_State *L = fs->ls->L;
+  const char *msg;
+  int line = fs->f->linedefined;
+  const char *where = (line == 0)
+                      ? "main function"
+                      : luaO_pushfstring(L, "function at line %d", line);
+  msg = luaO_pushfstring(L, "too many %s (limit is %d) in %s",
+                             what, limit, where);
+  luaX_syntaxerror(fs->ls, msg);
+}
+
+
+static void checklimit (FuncState *fs, int v, int l, const char *what) {
+  if (v > l) errorlimit(fs, l, what);
+}
+
+
+/*
+** Test whether next token is 'c'; if so, skip it.
+*/
+static int testnext (LexState *ls, int c) {
+  if (ls->t.token == c) {
+    luaX_next(ls);
+    return 1;
+  }
+  else return 0;
+}
+
+
+/*
+** Check that next token is 'c'.
+*/
+static void check (LexState *ls, int c) {
+  if (ls->t.token != c)
+    error_expected(ls, c);
+}
+
+
+/*
+** Check that next token is 'c' and skip it.
+*/
+static void checknext (LexState *ls, int c) {
+  check(ls, c);
+  luaX_next(ls);
+}
+
+
+#define check_condition(ls,c,msg)	{ if (!(c)) luaX_syntaxerror(ls, msg); }
+
+
+/*
+** Check that next token is 'what' and skip it. In case of error,
+** raise an error that the expected 'what' should match a 'who'
+** in line 'where' (if that is not the current line).
+*/
+static void check_match (LexState *ls, int what, int who, int where) {
+  if (unlikely(!testnext(ls, what))) {
+    if (where == ls->linenumber)  /* all in the same line? */
+      error_expected(ls, what);  /* do not need a complex message */
+    else {
+      luaX_syntaxerror(ls, luaO_pushfstring(ls->L,
+             "%s expected (to close %s at line %d)",
+              luaX_token2str(ls, what), luaX_token2str(ls, who), where));
+    }
+  }
+}
+
+
+static TString *str_checkname (LexState *ls) {
+  TString *ts;
+  check(ls, TK_NAME);
+  ts = ls->t.seminfo.ts;
+  luaX_next(ls);
+  return ts;
+}
+
+
+static void init_exp (expdesc *e, expkind k, int i) {
+  e->f = e->t = NO_JUMP;
+  e->k = k;
+  e->u.info = i;
+}
+
+
+static void codestring (expdesc *e, TString *s) {
+  e->f = e->t = NO_JUMP;
+  e->k = VKSTR;
+  e->u.strval = s;
+}
+
+
+static void codename (LexState *ls, expdesc *e) {
+  codestring(e, str_checkname(ls));
+}
+
+
+/*
+** Register a new local variable in the active 'Proto' (for debug
+** information).
+*/
+static int registerlocalvar (LexState *ls, FuncState *fs, TString *varname) {
+  Proto *f = fs->f;
+  int oldsize = f->sizelocvars;
+  luaM_growvector(ls->L, f->locvars, fs->ndebugvars, f->sizelocvars,
+                  LocVar, SHRT_MAX, "local variables");
+  while (oldsize < f->sizelocvars)
+    f->locvars[oldsize++].varname = NULL;
+  f->locvars[fs->ndebugvars].varname = varname;
+  f->locvars[fs->ndebugvars].startpc = fs->pc;
+  luaC_objbarrier(ls->L, f, varname);
+  return fs->ndebugvars++;
+}
+
+
+/*
+** Create a new local variable with the given 'name'. Return its index
+** in the function.
+*/
+static int new_localvar (LexState *ls, TString *name) {
+  lua_State *L = ls->L;
+  FuncState *fs = ls->fs;
+  Dyndata *dyd = ls->dyd;
+  Vardesc *var;
+  checklimit(fs, dyd->actvar.n + 1 - fs->firstlocal,
+                 MAXVARS, "local variables");
+  luaM_growvector(L, dyd->actvar.arr, dyd->actvar.n + 1,
+                  dyd->actvar.size, Vardesc, USHRT_MAX, "local variables");
+  var = &dyd->actvar.arr[dyd->actvar.n++];
+  var->vd.kind = VDKREG;  /* default */
+  var->vd.name = name;
+  return dyd->actvar.n - 1 - fs->firstlocal;
+}
+
+#define new_localvarliteral(ls,v) \
+    new_localvar(ls,  \
+      luaX_newstring(ls, "" v, (sizeof(v)/sizeof(char)) - 1));
+
+
+
+/*
+** Return the "variable description" (Vardesc) of a given variable.
+** (Unless noted otherwise, all variables are referred to by their
+** compiler indices.)
+*/
+static Vardesc *getlocalvardesc (FuncState *fs, int vidx) {
+  return &fs->ls->dyd->actvar.arr[fs->firstlocal + vidx];
+}
+
+
+/*
+** Convert 'nvar', a compiler index level, to it corresponding
+** stack index level. For that, search for the highest variable
+** below that level that is in the stack and uses its stack
+** index ('sidx').
+*/
+static int stacklevel (FuncState *fs, int nvar) {
+  while (nvar-- > 0) {
+    Vardesc *vd = getlocalvardesc(fs, nvar);  /* get variable */
+    if (vd->vd.kind != RDKCTC)  /* is in the stack? */
+      return vd->vd.sidx + 1;
+  }
+  return 0;  /* no variables in the stack */
+}
+
+
+/*
+** Return the number of variables in the stack for function 'fs'
+*/
+int luaY_nvarstack (FuncState *fs) {
+  return stacklevel(fs, fs->nactvar);
+}
+
+
+/*
+** Get the debug-information entry for current variable 'vidx'.
+*/
+static LocVar *localdebuginfo (FuncState *fs, int vidx) {
+  Vardesc *vd = getlocalvardesc(fs,  vidx);
+  if (vd->vd.kind == RDKCTC)
+    return NULL;  /* no debug info. for constants */
+  else {
+    int idx = vd->vd.pidx;
+    lua_assert(idx < fs->ndebugvars);
+    return &fs->f->locvars[idx];
+  }
+}
+
+
+/*
+** Create an expression representing variable 'vidx'
+*/
+static void init_var (FuncState *fs, expdesc *e, int vidx) {
+  e->f = e->t = NO_JUMP;
+  e->k = VLOCAL;
+  e->u.var.vidx = vidx;
+  e->u.var.sidx = getlocalvardesc(fs, vidx)->vd.sidx;
+}
+
+
+/*
+** Raises an error if variable described by 'e' is read only
+*/
+static void check_readonly (LexState *ls, expdesc *e) {
+  FuncState *fs = ls->fs;
+  TString *varname = NULL;  /* to be set if variable is const */
+  switch (e->k) {
+    case VCONST: {
+      varname = ls->dyd->actvar.arr[e->u.info].vd.name;
+      break;
+    }
+    case VLOCAL: {
+      Vardesc *vardesc = getlocalvardesc(fs, e->u.var.vidx);
+      if (vardesc->vd.kind != VDKREG)  /* not a regular variable? */
+        varname = vardesc->vd.name;
+      break;
+    }
+    case VUPVAL: {
+      Upvaldesc *up = &fs->f->upvalues[e->u.info];
+      if (up->kind != VDKREG)
+        varname = up->name;
+      break;
+    }
+    default:
+      return;  /* other cases cannot be read-only */
+  }
+  if (varname) {
+    const char *msg = luaO_pushfstring(ls->L,
+       "attempt to assign to const variable '%s'", getstr(varname));
+    luaK_semerror(ls, msg);  /* error */
+  }
+}
+
+
+/*
+** Start the scope for the last 'nvars' created variables.
+*/
+static void adjustlocalvars (LexState *ls, int nvars) {
+  FuncState *fs = ls->fs;
+  int stklevel = luaY_nvarstack(fs);
+  int i;
+  for (i = 0; i < nvars; i++) {
+    int vidx = fs->nactvar++;
+    Vardesc *var = getlocalvardesc(fs, vidx);
+    var->vd.sidx = stklevel++;
+    var->vd.pidx = registerlocalvar(ls, fs, var->vd.name);
+  }
+}
+
+
+/*
+** Close the scope for all variables up to level 'tolevel'.
+** (debug info.)
+*/
+static void removevars (FuncState *fs, int tolevel) {
+  fs->ls->dyd->actvar.n -= (fs->nactvar - tolevel);
+  while (fs->nactvar > tolevel) {
+    LocVar *var = localdebuginfo(fs, --fs->nactvar);
+    if (var)  /* does it have debug information? */
+      var->endpc = fs->pc;
+  }
+}
+
+
+/*
+** Search the upvalues of the function 'fs' for one
+** with the given 'name'.
+*/
+static int searchupvalue (FuncState *fs, TString *name) {
+  int i;
+  Upvaldesc *up = fs->f->upvalues;
+  for (i = 0; i < fs->nups; i++) {
+    if (eqstr(up[i].name, name)) return i;
+  }
+  return -1;  /* not found */
+}
+
+
+static Upvaldesc *allocupvalue (FuncState *fs) {
+  Proto *f = fs->f;
+  int oldsize = f->sizeupvalues;
+  checklimit(fs, fs->nups + 1, MAXUPVAL, "upvalues");
+  luaM_growvector(fs->ls->L, f->upvalues, fs->nups, f->sizeupvalues,
+                  Upvaldesc, MAXUPVAL, "upvalues");
+  while (oldsize < f->sizeupvalues)
+    f->upvalues[oldsize++].name = NULL;
+  return &f->upvalues[fs->nups++];
+}
+
+
+static int newupvalue (FuncState *fs, TString *name, expdesc *v) {
+  Upvaldesc *up = allocupvalue(fs);
+  FuncState *prev = fs->prev;
+  if (v->k == VLOCAL) {
+    up->instack = 1;
+    up->idx = v->u.var.sidx;
+    up->kind = getlocalvardesc(prev, v->u.var.vidx)->vd.kind;
+    lua_assert(eqstr(name, getlocalvardesc(prev, v->u.var.vidx)->vd.name));
+  }
+  else {
+    up->instack = 0;
+    up->idx = cast_byte(v->u.info);
+    up->kind = prev->f->upvalues[v->u.info].kind;
+    lua_assert(eqstr(name, prev->f->upvalues[v->u.info].name));
+  }
+  up->name = name;
+  luaC_objbarrier(fs->ls->L, fs->f, name);
+  return fs->nups - 1;
+}
+
+
+/*
+** Look for an active local variable with the name 'n' in the
+** function 'fs'. If found, initialize 'var' with it and return
+** its expression kind; otherwise return -1.
+*/
+static int searchvar (FuncState *fs, TString *n, expdesc *var) {
+  int i;
+  for (i = cast_int(fs->nactvar) - 1; i >= 0; i--) {
+    Vardesc *vd = getlocalvardesc(fs, i);
+    if (eqstr(n, vd->vd.name)) {  /* found? */
+      if (vd->vd.kind == RDKCTC)  /* compile-time constant? */
+        init_exp(var, VCONST, fs->firstlocal + i);
+      else  /* real variable */
+        init_var(fs, var, i);
+      return var->k;
+    }
+  }
+  return -1;  /* not found */
+}
+
+
+/*
+** Mark block where variable at given level was defined
+** (to emit close instructions later).
+*/
+static void markupval (FuncState *fs, int level) {
+  BlockCnt *bl = fs->bl;
+  while (bl->nactvar > level)
+    bl = bl->previous;
+  bl->upval = 1;
+  fs->needclose = 1;
+}
+
+
+/*
+** Find a variable with the given name 'n'. If it is an upvalue, add
+** this upvalue into all intermediate functions. If it is a global, set
+** 'var' as 'void' as a flag.
+*/
+static void singlevaraux (FuncState *fs, TString *n, expdesc *var, int base) {
+  if (fs == NULL)  /* no more levels? */
+    init_exp(var, VVOID, 0);  /* default is global */
+  else {
+    int v = searchvar(fs, n, var);  /* look up locals at current level */
+    if (v >= 0) {  /* found? */
+      if (v == VLOCAL && !base)
+        markupval(fs, var->u.var.vidx);  /* local will be used as an upval */
+    }
+    else {  /* not found as local at current level; try upvalues */
+      int idx = searchupvalue(fs, n);  /* try existing upvalues */
+      if (idx < 0) {  /* not found? */
+        singlevaraux(fs->prev, n, var, 0);  /* try upper levels */
+        if (var->k == VLOCAL || var->k == VUPVAL)  /* local or upvalue? */
+          idx  = newupvalue(fs, n, var);  /* will be a new upvalue */
+        else  /* it is a global or a constant */
+          return;  /* don't need to do anything at this level */
+      }
+      init_exp(var, VUPVAL, idx);  /* new or old upvalue */
+    }
+  }
+}
+
+
+/*
+** Find a variable with the given name 'n', handling global variables
+** too.
+*/
+static void singlevar (LexState *ls, expdesc *var) {
+  TString *varname = str_checkname(ls);
+  FuncState *fs = ls->fs;
+  singlevaraux(fs, varname, var, 1);
+  if (var->k == VVOID) {  /* global name? */
+    expdesc key;
+    singlevaraux(fs, ls->envn, var, 1);  /* get environment variable */
+    lua_assert(var->k != VVOID);  /* this one must exist */
+    codestring(&key, varname);  /* key is variable name */
+    luaK_indexed(fs, var, &key);  /* env[varname] */
+  }
+}
+
+
+/*
+** Adjust the number of results from an expression list 'e' with 'nexps'
+** expressions to 'nvars' values.
+*/
+static void adjust_assign (LexState *ls, int nvars, int nexps, expdesc *e) {
+  FuncState *fs = ls->fs;
+  int needed = nvars - nexps;  /* extra values needed */
+  if (hasmultret(e->k)) {  /* last expression has multiple returns? */
+    int extra = needed + 1;  /* discount last expression itself */
+    if (extra < 0)
+      extra = 0;
+    luaK_setreturns(fs, e, extra);  /* last exp. provides the difference */
+  }
+  else {
+    if (e->k != VVOID)  /* at least one expression? */
+      luaK_exp2nextreg(fs, e);  /* close last expression */
+    if (needed > 0)  /* missing values? */
+      luaK_nil(fs, fs->freereg, needed);  /* complete with nils */
+  }
+  if (needed > 0)
+    luaK_reserveregs(fs, needed);  /* registers for extra values */
+  else  /* adding 'needed' is actually a subtraction */
+    fs->freereg += needed;  /* remove extra values */
+}
+
+
+/*
+** Macros to limit the maximum recursion depth while parsing
+*/
+#define enterlevel(ls)	luaE_enterCcall((ls)->L)
+
+#define leavelevel(ls)	luaE_exitCcall((ls)->L)
+
+
+/*
+** Generates an error that a goto jumps into the scope of some
+** local variable.
+*/
+static l_noret jumpscopeerror (LexState *ls, Labeldesc *gt) {
+  const char *varname = getstr(getlocalvardesc(ls->fs, gt->nactvar)->vd.name);
+  const char *msg = "<goto %s> at line %d jumps into the scope of local '%s'";
+  msg = luaO_pushfstring(ls->L, msg, getstr(gt->name), gt->line, varname);
+  luaK_semerror(ls, msg);  /* raise the error */
+}
+
+
+/*
+** Solves the goto at index 'g' to given 'label' and removes it
+** from the list of pending goto's.
+** If it jumps into the scope of some variable, raises an error.
+*/
+static void solvegoto (LexState *ls, int g, Labeldesc *label) {
+  int i;
+  Labellist *gl = &ls->dyd->gt;  /* list of goto's */
+  Labeldesc *gt = &gl->arr[g];  /* goto to be resolved */
+  lua_assert(eqstr(gt->name, label->name));
+  if (unlikely(gt->nactvar < label->nactvar))  /* enter some scope? */
+    jumpscopeerror(ls, gt);
+  luaK_patchlist(ls->fs, gt->pc, label->pc);
+  for (i = g; i < gl->n - 1; i++)  /* remove goto from pending list */
+    gl->arr[i] = gl->arr[i + 1];
+  gl->n--;
+}
+
+
+/*
+** Search for an active label with the given name.
+*/
+static Labeldesc *findlabel (LexState *ls, TString *name) {
+  int i;
+  Dyndata *dyd = ls->dyd;
+  /* check labels in current function for a match */
+  for (i = ls->fs->firstlabel; i < dyd->label.n; i++) {
+    Labeldesc *lb = &dyd->label.arr[i];
+    if (eqstr(lb->name, name))  /* correct label? */
+      return lb;
+  }
+  return NULL;  /* label not found */
+}
+
+
+/*
+** Adds a new label/goto in the corresponding list.
+*/
+static int newlabelentry (LexState *ls, Labellist *l, TString *name,
+                          int line, int pc) {
+  int n = l->n;
+  luaM_growvector(ls->L, l->arr, n, l->size,
+                  Labeldesc, SHRT_MAX, "labels/gotos");
+  l->arr[n].name = name;
+  l->arr[n].line = line;
+  l->arr[n].nactvar = ls->fs->nactvar;
+  l->arr[n].close = 0;
+  l->arr[n].pc = pc;
+  l->n = n + 1;
+  return n;
+}
+
+
+static int newgotoentry (LexState *ls, TString *name, int line, int pc) {
+  return newlabelentry(ls, &ls->dyd->gt, name, line, pc);
+}
+
+
+/*
+** Solves forward jumps. Check whether new label 'lb' matches any
+** pending gotos in current block and solves them. Return true
+** if any of the goto's need to close upvalues.
+*/
+static int solvegotos (LexState *ls, Labeldesc *lb) {
+  Labellist *gl = &ls->dyd->gt;
+  int i = ls->fs->bl->firstgoto;
+  int needsclose = 0;
+  while (i < gl->n) {
+    if (eqstr(gl->arr[i].name, lb->name)) {
+      needsclose |= gl->arr[i].close;
+      solvegoto(ls, i, lb);  /* will remove 'i' from the list */
+    }
+    else
+      i++;
+  }
+  return needsclose;
+}
+
+
+/*
+** Create a new label with the given 'name' at the given 'line'.
+** 'last' tells whether label is the last non-op statement in its
+** block. Solves all pending goto's to this new label and adds
+** a close instruction if necessary.
+** Returns true iff it added a close instruction.
+*/
+static int createlabel (LexState *ls, TString *name, int line,
+                        int last) {
+  FuncState *fs = ls->fs;
+  Labellist *ll = &ls->dyd->label;
+  int l = newlabelentry(ls, ll, name, line, luaK_getlabel(fs));
+  if (last) {  /* label is last no-op statement in the block? */
+    /* assume that locals are already out of scope */
+    ll->arr[l].nactvar = fs->bl->nactvar;
+  }
+  if (solvegotos(ls, &ll->arr[l])) {  /* need close? */
+    luaK_codeABC(fs, OP_CLOSE, luaY_nvarstack(fs), 0, 0);
+    return 1;
+  }
+  return 0;
+}
+
+
+/*
+** Adjust pending gotos to outer level of a block.
+*/
+static void movegotosout (FuncState *fs, BlockCnt *bl) {
+  int i;
+  Labellist *gl = &fs->ls->dyd->gt;
+  /* correct pending gotos to current block */
+  for (i = bl->firstgoto; i < gl->n; i++) {  /* for each pending goto */
+    Labeldesc *gt = &gl->arr[i];
+    /* leaving a variable scope? */
+    if (stacklevel(fs, gt->nactvar) > stacklevel(fs, bl->nactvar))
+      gt->close |= bl->upval;  /* jump may need a close */
+    gt->nactvar = bl->nactvar;  /* update goto level */
+  }
+}
+
+
+static void enterblock (FuncState *fs, BlockCnt *bl, lu_byte isloop) {
+  bl->isloop = isloop;
+  bl->nactvar = fs->nactvar;
+  bl->firstlabel = fs->ls->dyd->label.n;
+  bl->firstgoto = fs->ls->dyd->gt.n;
+  bl->upval = 0;
+  bl->insidetbc = (fs->bl != NULL && fs->bl->insidetbc);
+  bl->previous = fs->bl;
+  fs->bl = bl;
+  lua_assert(fs->freereg == luaY_nvarstack(fs));
+}
+
+
+/*
+** generates an error for an undefined 'goto'.
+*/
+static l_noret undefgoto (LexState *ls, Labeldesc *gt) {
+  const char *msg;
+  if (eqstr(gt->name, luaS_newliteral(ls->L, "break"))) {
+    msg = "break outside loop at line %d";
+    msg = luaO_pushfstring(ls->L, msg, gt->line);
+  }
+  else {
+    msg = "no visible label '%s' for <goto> at line %d";
+    msg = luaO_pushfstring(ls->L, msg, getstr(gt->name), gt->line);
+  }
+  luaK_semerror(ls, msg);
+}
+
+
+static void leaveblock (FuncState *fs) {
+  BlockCnt *bl = fs->bl;
+  LexState *ls = fs->ls;
+  int hasclose = 0;
+  int stklevel = stacklevel(fs, bl->nactvar);  /* level outside the block */
+  if (bl->isloop)  /* fix pending breaks? */
+    hasclose = createlabel(ls, luaS_newliteral(ls->L, "break"), 0, 0);
+  if (!hasclose && bl->previous && bl->upval)
+    luaK_codeABC(fs, OP_CLOSE, stklevel, 0, 0);
+  fs->bl = bl->previous;
+  removevars(fs, bl->nactvar);
+  lua_assert(bl->nactvar == fs->nactvar);
+  fs->freereg = stklevel;  /* free registers */
+  ls->dyd->label.n = bl->firstlabel;  /* remove local labels */
+  if (bl->previous)  /* inner block? */
+    movegotosout(fs, bl);  /* update pending gotos to outer block */
+  else {
+    if (bl->firstgoto < ls->dyd->gt.n)  /* pending gotos in outer block? */
+      undefgoto(ls, &ls->dyd->gt.arr[bl->firstgoto]);  /* error */
+  }
+}
+
+
+/*
+** adds a new prototype into list of prototypes
+*/
+static Proto *addprototype (LexState *ls) {
+  Proto *clp;
+  lua_State *L = ls->L;
+  FuncState *fs = ls->fs;
+  Proto *f = fs->f;  /* prototype of current function */
+  if (fs->np >= f->sizep) {
+    int oldsize = f->sizep;
+    luaM_growvector(L, f->p, fs->np, f->sizep, Proto *, MAXARG_Bx, "functions");
+    while (oldsize < f->sizep)
+      f->p[oldsize++] = NULL;
+  }
+  f->p[fs->np++] = clp = luaF_newproto(L);
+  luaC_objbarrier(L, f, clp);
+  return clp;
+}
+
+
+/*
+** codes instruction to create new closure in parent function.
+** The OP_CLOSURE instruction uses the last available register,
+** so that, if it invokes the GC, the GC knows which registers
+** are in use at that time.
+
+*/
+static void codeclosure (LexState *ls, expdesc *v) {
+  FuncState *fs = ls->fs->prev;
+  init_exp(v, VRELOC, luaK_codeABx(fs, OP_CLOSURE, 0, fs->np - 1));
+  luaK_exp2nextreg(fs, v);  /* fix it at the last register */
+}
+
+
+static void open_func (LexState *ls, FuncState *fs, BlockCnt *bl) {
+  Proto *f = fs->f;
+  fs->prev = ls->fs;  /* linked list of funcstates */
+  fs->ls = ls;
+  ls->fs = fs;
+  fs->pc = 0;
+  fs->previousline = f->linedefined;
+  fs->iwthabs = 0;
+  fs->lasttarget = 0;
+  fs->freereg = 0;
+  fs->nk = 0;
+  fs->nabslineinfo = 0;
+  fs->np = 0;
+  fs->nups = 0;
+  fs->ndebugvars = 0;
+  fs->nactvar = 0;
+  fs->needclose = 0;
+  fs->firstlocal = ls->dyd->actvar.n;
+  fs->firstlabel = ls->dyd->label.n;
+  fs->bl = NULL;
+  f->source = ls->source;
+  luaC_objbarrier(ls->L, f, f->source);
+  f->maxstacksize = 2;  /* registers 0/1 are always valid */
+  enterblock(fs, bl, 0);
+}
+
+
+static void close_func (LexState *ls) {
+  lua_State *L = ls->L;
+  FuncState *fs = ls->fs;
+  Proto *f = fs->f;
+  luaK_ret(fs, luaY_nvarstack(fs), 0);  /* final return */
+  leaveblock(fs);
+  lua_assert(fs->bl == NULL);
+  luaK_finish(fs);
+  luaM_shrinkvector(L, f->code, f->sizecode, fs->pc, Instruction);
+  luaM_shrinkvector(L, f->lineinfo, f->sizelineinfo, fs->pc, ls_byte);
+  luaM_shrinkvector(L, f->abslineinfo, f->sizeabslineinfo,
+                       fs->nabslineinfo, AbsLineInfo);
+  luaM_shrinkvector(L, f->k, f->sizek, fs->nk, TValue);
+  luaM_shrinkvector(L, f->p, f->sizep, fs->np, Proto *);
+  luaM_shrinkvector(L, f->locvars, f->sizelocvars, fs->ndebugvars, LocVar);
+  luaM_shrinkvector(L, f->upvalues, f->sizeupvalues, fs->nups, Upvaldesc);
+  ls->fs = fs->prev;
+  luaC_checkGC(L);
+}
+
+
+
+/*============================================================*/
+/* GRAMMAR RULES */
+/*============================================================*/
+
+
+/*
+** check whether current token is in the follow set of a block.
+** 'until' closes syntactical blocks, but do not close scope,
+** so it is handled in separate.
+*/
+static int block_follow (LexState *ls, int withuntil) {
+  switch (ls->t.token) {
+    case TK_ELSE: case TK_ELSEIF:
+    case TK_END: case TK_EOS:
+      return 1;
+    case TK_UNTIL: return withuntil;
+    default: return 0;
+  }
+}
+
+
+static void statlist (LexState *ls) {
+  /* statlist -> { stat [';'] } */
+  while (!block_follow(ls, 1)) {
+    if (ls->t.token == TK_RETURN) {
+      statement(ls);
+      return;  /* 'return' must be last statement */
+    }
+    statement(ls);
+  }
+}
+
+
+static void fieldsel (LexState *ls, expdesc *v) {
+  /* fieldsel -> ['.' | ':'] NAME */
+  FuncState *fs = ls->fs;
+  expdesc key;
+  luaK_exp2anyregup(fs, v);
+  luaX_next(ls);  /* skip the dot or colon */
+  codename(ls, &key);
+  luaK_indexed(fs, v, &key);
+}
+
+
+static void yindex (LexState *ls, expdesc *v) {
+  /* index -> '[' expr ']' */
+  luaX_next(ls);  /* skip the '[' */
+  expr(ls, v);
+  luaK_exp2val(ls->fs, v);
+  checknext(ls, ']');
+}
+
+
+/*
+** {======================================================================
+** Rules for Constructors
+** =======================================================================
+*/
+
+
+typedef struct ConsControl {
+  expdesc v;  /* last list item read */
+  expdesc *t;  /* table descriptor */
+  int nh;  /* total number of 'record' elements */
+  int na;  /* number of array elements already stored */
+  int tostore;  /* number of array elements pending to be stored */
+} ConsControl;
+
+
+static void recfield (LexState *ls, ConsControl *cc) {
+  /* recfield -> (NAME | '['exp']') = exp */
+  FuncState *fs = ls->fs;
+  int reg = ls->fs->freereg;
+  expdesc tab, key, val;
+  if (ls->t.token == TK_NAME) {
+    checklimit(fs, cc->nh, MAX_INT, "items in a constructor");
+    codename(ls, &key);
+  }
+  else  /* ls->t.token == '[' */
+    yindex(ls, &key);
+  cc->nh++;
+  checknext(ls, '=');
+  tab = *cc->t;
+  luaK_indexed(fs, &tab, &key);
+  expr(ls, &val);
+  luaK_storevar(fs, &tab, &val);
+  fs->freereg = reg;  /* free registers */
+}
+
+
+static void closelistfield (FuncState *fs, ConsControl *cc) {
+  if (cc->v.k == VVOID) return;  /* there is no list item */
+  luaK_exp2nextreg(fs, &cc->v);
+  cc->v.k = VVOID;
+  if (cc->tostore == LFIELDS_PER_FLUSH) {
+    luaK_setlist(fs, cc->t->u.info, cc->na, cc->tostore);  /* flush */
+    cc->na += cc->tostore;
+    cc->tostore = 0;  /* no more items pending */
+  }
+}
+
+
+static void lastlistfield (FuncState *fs, ConsControl *cc) {
+  if (cc->tostore == 0) return;
+  if (hasmultret(cc->v.k)) {
+    luaK_setmultret(fs, &cc->v);
+    luaK_setlist(fs, cc->t->u.info, cc->na, LUA_MULTRET);
+    cc->na--;  /* do not count last expression (unknown number of elements) */
+  }
+  else {
+    if (cc->v.k != VVOID)
+      luaK_exp2nextreg(fs, &cc->v);
+    luaK_setlist(fs, cc->t->u.info, cc->na, cc->tostore);
+  }
+  cc->na += cc->tostore;
+}
+
+
+static void listfield (LexState *ls, ConsControl *cc) {
+  /* listfield -> exp */
+  expr(ls, &cc->v);
+  cc->tostore++;
+}
+
+
+static void field (LexState *ls, ConsControl *cc) {
+  /* field -> listfield | recfield */
+  switch(ls->t.token) {
+    case TK_NAME: {  /* may be 'listfield' or 'recfield' */
+      if (luaX_lookahead(ls) != '=')  /* expression? */
+        listfield(ls, cc);
+      else
+        recfield(ls, cc);
+      break;
+    }
+    case '[': {
+      recfield(ls, cc);
+      break;
+    }
+    default: {
+      listfield(ls, cc);
+      break;
+    }
+  }
+}
+
+
+static void constructor (LexState *ls, expdesc *t) {
+  /* constructor -> '{' [ field { sep field } [sep] ] '}'
+     sep -> ',' | ';' */
+  FuncState *fs = ls->fs;
+  int line = ls->linenumber;
+  int pc = luaK_codeABC(fs, OP_NEWTABLE, 0, 0, 0);
+  ConsControl cc;
+  luaK_code(fs, 0);  /* space for extra arg. */
+  cc.na = cc.nh = cc.tostore = 0;
+  cc.t = t;
+  init_exp(t, VNONRELOC, fs->freereg);  /* table will be at stack top */
+  luaK_reserveregs(fs, 1);
+  init_exp(&cc.v, VVOID, 0);  /* no value (yet) */
+  checknext(ls, '{');
+  do {
+    lua_assert(cc.v.k == VVOID || cc.tostore > 0);
+    if (ls->t.token == '}') break;
+    closelistfield(fs, &cc);
+    field(ls, &cc);
+  } while (testnext(ls, ',') || testnext(ls, ';'));
+  check_match(ls, '}', '{', line);
+  lastlistfield(fs, &cc);
+  luaK_settablesize(fs, pc, t->u.info, cc.na, cc.nh);
+}
+
+/* }====================================================================== */
+
+
+static void setvararg (FuncState *fs, int nparams) {
+  fs->f->is_vararg = 1;
+  luaK_codeABC(fs, OP_VARARGPREP, nparams, 0, 0);
+}
+
+
+static void parlist (LexState *ls) {
+  /* parlist -> [ param { ',' param } ] */
+  FuncState *fs = ls->fs;
+  Proto *f = fs->f;
+  int nparams = 0;
+  int isvararg = 0;
+  if (ls->t.token != ')') {  /* is 'parlist' not empty? */
+    do {
+      switch (ls->t.token) {
+        case TK_NAME: {  /* param -> NAME */
+          new_localvar(ls, str_checkname(ls));
+          nparams++;
+          break;
+        }
+        case TK_DOTS: {  /* param -> '...' */
+          luaX_next(ls);
+          isvararg = 1;
+          break;
+        }
+        default: luaX_syntaxerror(ls, "<name> or '...' expected");
+      }
+    } while (!isvararg && testnext(ls, ','));
+  }
+  adjustlocalvars(ls, nparams);
+  f->numparams = cast_byte(fs->nactvar);
+  if (isvararg)
+    setvararg(fs, f->numparams);  /* declared vararg */
+  luaK_reserveregs(fs, fs->nactvar);  /* reserve registers for parameters */
+}
+
+
+static void body (LexState *ls, expdesc *e, int ismethod, int line) {
+  /* body ->  '(' parlist ')' block END */
+  FuncState new_fs;
+  BlockCnt bl;
+  new_fs.f = addprototype(ls);
+  new_fs.f->linedefined = line;
+  open_func(ls, &new_fs, &bl);
+  checknext(ls, '(');
+  if (ismethod) {
+    new_localvarliteral(ls, "self");  /* create 'self' parameter */
+    adjustlocalvars(ls, 1);
+  }
+  parlist(ls);
+  checknext(ls, ')');
+  statlist(ls);
+  new_fs.f->lastlinedefined = ls->linenumber;
+  check_match(ls, TK_END, TK_FUNCTION, line);
+  codeclosure(ls, e);
+  close_func(ls);
+}
+
+
+static int explist (LexState *ls, expdesc *v) {
+  /* explist -> expr { ',' expr } */
+  int n = 1;  /* at least one expression */
+  expr(ls, v);
+  while (testnext(ls, ',')) {
+    luaK_exp2nextreg(ls->fs, v);
+    expr(ls, v);
+    n++;
+  }
+  return n;
+}
+
+
+static void funcargs (LexState *ls, expdesc *f, int line) {
+  FuncState *fs = ls->fs;
+  expdesc args;
+  int base, nparams;
+  switch (ls->t.token) {
+    case '(': {  /* funcargs -> '(' [ explist ] ')' */
+      luaX_next(ls);
+      if (ls->t.token == ')')  /* arg list is empty? */
+        args.k = VVOID;
+      else {
+        explist(ls, &args);
+        if (hasmultret(args.k))
+          luaK_setmultret(fs, &args);
+      }
+      check_match(ls, ')', '(', line);
+      break;
+    }
+    case '{': {  /* funcargs -> constructor */
+      constructor(ls, &args);
+      break;
+    }
+    case TK_STRING: {  /* funcargs -> STRING */
+      codestring(&args, ls->t.seminfo.ts);
+      luaX_next(ls);  /* must use 'seminfo' before 'next' */
+      break;
+    }
+    default: {
+      luaX_syntaxerror(ls, "function arguments expected");
+    }
+  }
+  lua_assert(f->k == VNONRELOC);
+  base = f->u.info;  /* base register for call */
+  if (hasmultret(args.k))
+    nparams = LUA_MULTRET;  /* open call */
+  else {
+    if (args.k != VVOID)
+      luaK_exp2nextreg(fs, &args);  /* close last argument */
+    nparams = fs->freereg - (base+1);
+  }
+  init_exp(f, VCALL, luaK_codeABC(fs, OP_CALL, base, nparams+1, 2));
+  luaK_fixline(fs, line);
+  fs->freereg = base+1;  /* call remove function and arguments and leaves
+                            (unless changed) one result */
+}
+
+
+
+
+/*
+** {======================================================================
+** Expression parsing
+** =======================================================================
+*/
+
+
+static void primaryexp (LexState *ls, expdesc *v) {
+  /* primaryexp -> NAME | '(' expr ')' */
+  switch (ls->t.token) {
+    case '(': {
+      int line = ls->linenumber;
+      luaX_next(ls);
+      expr(ls, v);
+      check_match(ls, ')', '(', line);
+      luaK_dischargevars(ls->fs, v);
+      return;
+    }
+    case TK_NAME: {
+      singlevar(ls, v);
+      return;
+    }
+    default: {
+      luaX_syntaxerror(ls, "unexpected symbol");
+    }
+  }
+}
+
+
+static void suffixedexp (LexState *ls, expdesc *v) {
+  /* suffixedexp ->
+       primaryexp { '.' NAME | '[' exp ']' | ':' NAME funcargs | funcargs } */
+  FuncState *fs = ls->fs;
+  int line = ls->linenumber;
+  primaryexp(ls, v);
+  for (;;) {
+    switch (ls->t.token) {
+      case '.': {  /* fieldsel */
+        fieldsel(ls, v);
+        break;
+      }
+      case '[': {  /* '[' exp ']' */
+        expdesc key;
+        luaK_exp2anyregup(fs, v);
+        yindex(ls, &key);
+        luaK_indexed(fs, v, &key);
+        break;
+      }
+      case ':': {  /* ':' NAME funcargs */
+        expdesc key;
+        luaX_next(ls);
+        codename(ls, &key);
+        luaK_self(fs, v, &key);
+        funcargs(ls, v, line);
+        break;
+      }
+      case '(': case TK_STRING: case '{': {  /* funcargs */
+        luaK_exp2nextreg(fs, v);
+        funcargs(ls, v, line);
+        break;
+      }
+      default: return;
+    }
+  }
+}
+
+
+static void simpleexp (LexState *ls, expdesc *v) {
+  /* simpleexp -> FLT | INT | STRING | NIL | TRUE | FALSE | ... |
+                  constructor | FUNCTION body | suffixedexp */
+  switch (ls->t.token) {
+    case TK_FLT: {
+      init_exp(v, VKFLT, 0);
+      v->u.nval = ls->t.seminfo.r;
+      break;
+    }
+    case TK_INT: {
+      init_exp(v, VKINT, 0);
+      v->u.ival = ls->t.seminfo.i;
+      break;
+    }
+    case TK_STRING: {
+      codestring(v, ls->t.seminfo.ts);
+      break;
+    }
+    case TK_NIL: {
+      init_exp(v, VNIL, 0);
+      break;
+    }
+    case TK_TRUE: {
+      init_exp(v, VTRUE, 0);
+      break;
+    }
+    case TK_FALSE: {
+      init_exp(v, VFALSE, 0);
+      break;
+    }
+    case TK_DOTS: {  /* vararg */
+      FuncState *fs = ls->fs;
+      check_condition(ls, fs->f->is_vararg,
+                      "cannot use '...' outside a vararg function");
+      init_exp(v, VVARARG, luaK_codeABC(fs, OP_VARARG, 0, 0, 1));
+      break;
+    }
+    case '{': {  /* constructor */
+      constructor(ls, v);
+      return;
+    }
+    case TK_FUNCTION: {
+      luaX_next(ls);
+      body(ls, v, 0, ls->linenumber);
+      return;
+    }
+    default: {
+      suffixedexp(ls, v);
+      return;
+    }
+  }
+  luaX_next(ls);
+}
+
+
+static UnOpr getunopr (int op) {
+  switch (op) {
+    case TK_NOT: return OPR_NOT;
+    case '-': return OPR_MINUS;
+    case '~': return OPR_BNOT;
+    case '#': return OPR_LEN;
+    default: return OPR_NOUNOPR;
+  }
+}
+
+
+static BinOpr getbinopr (int op) {
+  switch (op) {
+    case '+': return OPR_ADD;
+    case '-': return OPR_SUB;
+    case '*': return OPR_MUL;
+    case '%': return OPR_MOD;
+    case '^': return OPR_POW;
+    case '/': return OPR_DIV;
+    case TK_IDIV: return OPR_IDIV;
+    case '&': return OPR_BAND;
+    case '|': return OPR_BOR;
+    case '~': return OPR_BXOR;
+    case TK_SHL: return OPR_SHL;
+    case TK_SHR: return OPR_SHR;
+    case TK_CONCAT: return OPR_CONCAT;
+    case TK_NE: return OPR_NE;
+    case TK_EQ: return OPR_EQ;
+    case '<': return OPR_LT;
+    case TK_LE: return OPR_LE;
+    case '>': return OPR_GT;
+    case TK_GE: return OPR_GE;
+    case TK_AND: return OPR_AND;
+    case TK_OR: return OPR_OR;
+    default: return OPR_NOBINOPR;
+  }
+}
+
+
+/*
+** Priority table for binary operators.
+*/
+static const struct {
+  lu_byte left;  /* left priority for each binary operator */
+  lu_byte right; /* right priority */
+} priority[] = {  /* ORDER OPR */
+   {10, 10}, {10, 10},           /* '+' '-' */
+   {11, 11}, {11, 11},           /* '*' '%' */
+   {14, 13},                  /* '^' (right associative) */
+   {11, 11}, {11, 11},           /* '/' '//' */
+   {6, 6}, {4, 4}, {5, 5},   /* '&' '|' '~' */
+   {7, 7}, {7, 7},           /* '<<' '>>' */
+   {9, 8},                   /* '..' (right associative) */
+   {3, 3}, {3, 3}, {3, 3},   /* ==, <, <= */
+   {3, 3}, {3, 3}, {3, 3},   /* ~=, >, >= */
+   {2, 2}, {1, 1}            /* and, or */
+};
+
+#define UNARY_PRIORITY	12  /* priority for unary operators */
+
+
+/*
+** subexpr -> (simpleexp | unop subexpr) { binop subexpr }
+** where 'binop' is any binary operator with a priority higher than 'limit'
+*/
+static BinOpr subexpr (LexState *ls, expdesc *v, int limit) {
+  BinOpr op;
+  UnOpr uop;
+  enterlevel(ls);
+  uop = getunopr(ls->t.token);
+  if (uop != OPR_NOUNOPR) {  /* prefix (unary) operator? */
+    int line = ls->linenumber;
+    luaX_next(ls);  /* skip operator */
+    subexpr(ls, v, UNARY_PRIORITY);
+    luaK_prefix(ls->fs, uop, v, line);
+  }
+  else simpleexp(ls, v);
+  /* expand while operators have priorities higher than 'limit' */
+  op = getbinopr(ls->t.token);
+  while (op != OPR_NOBINOPR && priority[op].left > limit) {
+    expdesc v2;
+    BinOpr nextop;
+    int line = ls->linenumber;
+    luaX_next(ls);  /* skip operator */
+    luaK_infix(ls->fs, op, v);
+    /* read sub-expression with higher priority */
+    nextop = subexpr(ls, &v2, priority[op].right);
+    luaK_posfix(ls->fs, op, v, &v2, line);
+    op = nextop;
+  }
+  leavelevel(ls);
+  return op;  /* return first untreated operator */
+}
+
+
+static void expr (LexState *ls, expdesc *v) {
+  subexpr(ls, v, 0);
+}
+
+/* }==================================================================== */
+
+
+
+/*
+** {======================================================================
+** Rules for Statements
+** =======================================================================
+*/
+
+
+static void block (LexState *ls) {
+  /* block -> statlist */
+  FuncState *fs = ls->fs;
+  BlockCnt bl;
+  enterblock(fs, &bl, 0);
+  statlist(ls);
+  leaveblock(fs);
+}
+
+
+/*
+** structure to chain all variables in the left-hand side of an
+** assignment
+*/
+struct LHS_assign {
+  struct LHS_assign *prev;
+  expdesc v;  /* variable (global, local, upvalue, or indexed) */
+};
+
+
+/*
+** check whether, in an assignment to an upvalue/local variable, the
+** upvalue/local variable is begin used in a previous assignment to a
+** table. If so, save original upvalue/local value in a safe place and
+** use this safe copy in the previous assignment.
+*/
+static void check_conflict (LexState *ls, struct LHS_assign *lh, expdesc *v) {
+  FuncState *fs = ls->fs;
+  int extra = fs->freereg;  /* eventual position to save local variable */
+  int conflict = 0;
+  for (; lh; lh = lh->prev) {  /* check all previous assignments */
+    if (vkisindexed(lh->v.k)) {  /* assignment to table field? */
+      if (lh->v.k == VINDEXUP) {  /* is table an upvalue? */
+        if (v->k == VUPVAL && lh->v.u.ind.t == v->u.info) {
+          conflict = 1;  /* table is the upvalue being assigned now */
+          lh->v.k = VINDEXSTR;
+          lh->v.u.ind.t = extra;  /* assignment will use safe copy */
+        }
+      }
+      else {  /* table is a register */
+        if (v->k == VLOCAL && lh->v.u.ind.t == v->u.var.sidx) {
+          conflict = 1;  /* table is the local being assigned now */
+          lh->v.u.ind.t = extra;  /* assignment will use safe copy */
+        }
+        /* is index the local being assigned? */
+        if (lh->v.k == VINDEXED && v->k == VLOCAL &&
+            lh->v.u.ind.idx == v->u.var.sidx) {
+          conflict = 1;
+          lh->v.u.ind.idx = extra;  /* previous assignment will use safe copy */
+        }
+      }
+    }
+  }
+  if (conflict) {
+    /* copy upvalue/local value to a temporary (in position 'extra') */
+    if (v->k == VLOCAL)
+      luaK_codeABC(fs, OP_MOVE, extra, v->u.var.sidx, 0);
+    else
+      luaK_codeABC(fs, OP_GETUPVAL, extra, v->u.info, 0);
+    luaK_reserveregs(fs, 1);
+  }
+}
+
+/*
+** Parse and compile a multiple assignment. The first "variable"
+** (a 'suffixedexp') was already read by the caller.
+**
+** assignment -> suffixedexp restassign
+** restassign -> ',' suffixedexp restassign | '=' explist
+*/
+static void restassign (LexState *ls, struct LHS_assign *lh, int nvars) {
+  expdesc e;
+  check_condition(ls, vkisvar(lh->v.k), "syntax error");
+  check_readonly(ls, &lh->v);
+  if (testnext(ls, ',')) {  /* restassign -> ',' suffixedexp restassign */
+    struct LHS_assign nv;
+    nv.prev = lh;
+    suffixedexp(ls, &nv.v);
+    if (!vkisindexed(nv.v.k))
+      check_conflict(ls, lh, &nv.v);
+    enterlevel(ls);  /* control recursion depth */
+    restassign(ls, &nv, nvars+1);
+    leavelevel(ls);
+  }
+  else {  /* restassign -> '=' explist */
+    int nexps;
+    checknext(ls, '=');
+    nexps = explist(ls, &e);
+    if (nexps != nvars)
+      adjust_assign(ls, nvars, nexps, &e);
+    else {
+      luaK_setoneret(ls->fs, &e);  /* close last expression */
+      luaK_storevar(ls->fs, &lh->v, &e);
+      return;  /* avoid default */
+    }
+  }
+  init_exp(&e, VNONRELOC, ls->fs->freereg-1);  /* default assignment */
+  luaK_storevar(ls->fs, &lh->v, &e);
+}
+
+
+static int cond (LexState *ls) {
+  /* cond -> exp */
+  expdesc v;
+  expr(ls, &v);  /* read condition */
+  if (v.k == VNIL) v.k = VFALSE;  /* 'falses' are all equal here */
+  luaK_goiftrue(ls->fs, &v);
+  return v.f;
+}
+
+
+static void gotostat (LexState *ls) {
+  FuncState *fs = ls->fs;
+  int line = ls->linenumber;
+  TString *name = str_checkname(ls);  /* label's name */
+  Labeldesc *lb = findlabel(ls, name);
+  if (lb == NULL)  /* no label? */
+    /* forward jump; will be resolved when the label is declared */
+    newgotoentry(ls, name, line, luaK_jump(fs));
+  else {  /* found a label */
+    /* backward jump; will be resolved here */
+    int lblevel = stacklevel(fs, lb->nactvar);  /* label level */
+    if (luaY_nvarstack(fs) > lblevel)  /* leaving the scope of a variable? */
+      luaK_codeABC(fs, OP_CLOSE, lblevel, 0, 0);
+    /* create jump and link it to the label */
+    luaK_patchlist(fs, luaK_jump(fs), lb->pc);
+  }
+}
+
+
+/*
+** Break statement. Semantically equivalent to "goto break".
+*/
+static void breakstat (LexState *ls) {
+  int line = ls->linenumber;
+  luaX_next(ls);  /* skip break */
+  newgotoentry(ls, luaS_newliteral(ls->L, "break"), line, luaK_jump(ls->fs));
+}
+
+
+/*
+** Check whether there is already a label with the given 'name'.
+*/
+static void checkrepeated (LexState *ls, TString *name) {
+  Labeldesc *lb = findlabel(ls, name);
+  if (unlikely(lb != NULL)) {  /* already defined? */
+    const char *msg = "label '%s' already defined on line %d";
+    msg = luaO_pushfstring(ls->L, msg, getstr(name), lb->line);
+    luaK_semerror(ls, msg);  /* error */
+  }
+}
+
+
+static void labelstat (LexState *ls, TString *name, int line) {
+  /* label -> '::' NAME '::' */
+  checknext(ls, TK_DBCOLON);  /* skip double colon */
+  while (ls->t.token == ';' || ls->t.token == TK_DBCOLON)
+    statement(ls);  /* skip other no-op statements */
+  checkrepeated(ls, name);  /* check for repeated labels */
+  createlabel(ls, name, line, block_follow(ls, 0));
+}
+
+
+static void whilestat (LexState *ls, int line) {
+  /* whilestat -> WHILE cond DO block END */
+  FuncState *fs = ls->fs;
+  int whileinit;
+  int condexit;
+  BlockCnt bl;
+  luaX_next(ls);  /* skip WHILE */
+  whileinit = luaK_getlabel(fs);
+  condexit = cond(ls);
+  enterblock(fs, &bl, 1);
+  checknext(ls, TK_DO);
+  block(ls);
+  luaK_jumpto(fs, whileinit);
+  check_match(ls, TK_END, TK_WHILE, line);
+  leaveblock(fs);
+  luaK_patchtohere(fs, condexit);  /* false conditions finish the loop */
+}
+
+
+static void repeatstat (LexState *ls, int line) {
+  /* repeatstat -> REPEAT block UNTIL cond */
+  int condexit;
+  FuncState *fs = ls->fs;
+  int repeat_init = luaK_getlabel(fs);
+  BlockCnt bl1, bl2;
+  enterblock(fs, &bl1, 1);  /* loop block */
+  enterblock(fs, &bl2, 0);  /* scope block */
+  luaX_next(ls);  /* skip REPEAT */
+  statlist(ls);
+  check_match(ls, TK_UNTIL, TK_REPEAT, line);
+  condexit = cond(ls);  /* read condition (inside scope block) */
+  leaveblock(fs);  /* finish scope */
+  if (bl2.upval) {  /* upvalues? */
+    int exit = luaK_jump(fs);  /* normal exit must jump over fix */
+    luaK_patchtohere(fs, condexit);  /* repetition must close upvalues */
+    luaK_codeABC(fs, OP_CLOSE, stacklevel(fs, bl2.nactvar), 0, 0);
+    condexit = luaK_jump(fs);  /* repeat after closing upvalues */
+    luaK_patchtohere(fs, exit);  /* normal exit comes to here */
+  }
+  luaK_patchlist(fs, condexit, repeat_init);  /* close the loop */
+  leaveblock(fs);  /* finish loop */
+}
+
+
+/*
+** Read an expression and generate code to put its results in next
+** stack slot.
+**
+*/
+static void exp1 (LexState *ls) {
+  expdesc e;
+  expr(ls, &e);
+  luaK_exp2nextreg(ls->fs, &e);
+  lua_assert(e.k == VNONRELOC);
+}
+
+
+/*
+** Fix for instruction at position 'pc' to jump to 'dest'.
+** (Jump addresses are relative in Lua). 'back' true means
+** a back jump.
+*/
+static void fixforjump (FuncState *fs, int pc, int dest, int back) {
+  Instruction *jmp = &fs->f->code[pc];
+  int offset = dest - (pc + 1);
+  if (back)
+    offset = -offset;
+  if (unlikely(offset > MAXARG_Bx))
+    luaX_syntaxerror(fs->ls, "control structure too long");
+  SETARG_Bx(*jmp, offset);
+}
+
+
+/*
+** Generate code for a 'for' loop.
+*/
+static void forbody (LexState *ls, int base, int line, int nvars, int isgen) {
+  /* forbody -> DO block */
+  static const OpCode forprep[2] = {OP_FORPREP, OP_TFORPREP};
+  static const OpCode forloop[2] = {OP_FORLOOP, OP_TFORLOOP};
+  BlockCnt bl;
+  FuncState *fs = ls->fs;
+  int prep, endfor;
+  checknext(ls, TK_DO);
+  prep = luaK_codeABx(fs, forprep[isgen], base, 0);
+  enterblock(fs, &bl, 0);  /* scope for declared variables */
+  adjustlocalvars(ls, nvars);
+  luaK_reserveregs(fs, nvars);
+  block(ls);
+  leaveblock(fs);  /* end of scope for declared variables */
+  fixforjump(fs, prep, luaK_getlabel(fs), 0);
+  if (isgen) {  /* generic for? */
+    luaK_codeABC(fs, OP_TFORCALL, base, 0, nvars);
+    luaK_fixline(fs, line);
+  }
+  endfor = luaK_codeABx(fs, forloop[isgen], base, 0);
+  fixforjump(fs, endfor, prep + 1, 1);
+  luaK_fixline(fs, line);
+}
+
+
+static void fornum (LexState *ls, TString *varname, int line) {
+  /* fornum -> NAME = exp,exp[,exp] forbody */
+  FuncState *fs = ls->fs;
+  int base = fs->freereg;
+  new_localvarliteral(ls, "(for state)");
+  new_localvarliteral(ls, "(for state)");
+  new_localvarliteral(ls, "(for state)");
+  new_localvar(ls, varname);
+  checknext(ls, '=');
+  exp1(ls);  /* initial value */
+  checknext(ls, ',');
+  exp1(ls);  /* limit */
+  if (testnext(ls, ','))
+    exp1(ls);  /* optional step */
+  else {  /* default step = 1 */
+    luaK_int(fs, fs->freereg, 1);
+    luaK_reserveregs(fs, 1);
+  }
+  adjustlocalvars(ls, 3);  /* control variables */
+  forbody(ls, base, line, 1, 0);
+}
+
+
+static void forlist (LexState *ls, TString *indexname) {
+  /* forlist -> NAME {,NAME} IN explist forbody */
+  FuncState *fs = ls->fs;
+  expdesc e;
+  int nvars = 5;  /* gen, state, control, toclose, 'indexname' */
+  int line;
+  int base = fs->freereg;
+  /* create control variables */
+  new_localvarliteral(ls, "(for state)");
+  new_localvarliteral(ls, "(for state)");
+  new_localvarliteral(ls, "(for state)");
+  new_localvarliteral(ls, "(for state)");
+  /* create declared variables */
+  new_localvar(ls, indexname);
+  while (testnext(ls, ',')) {
+    new_localvar(ls, str_checkname(ls));
+    nvars++;
+  }
+  checknext(ls, TK_IN);
+  line = ls->linenumber;
+  adjust_assign(ls, 4, explist(ls, &e), &e);
+  adjustlocalvars(ls, 4);  /* control variables */
+  markupval(fs, fs->nactvar);  /* last control var. must be closed */
+  luaK_checkstack(fs, 3);  /* extra space to call generator */
+  forbody(ls, base, line, nvars - 4, 1);
+}
+
+
+static void forstat (LexState *ls, int line) {
+  /* forstat -> FOR (fornum | forlist) END */
+  FuncState *fs = ls->fs;
+  TString *varname;
+  BlockCnt bl;
+  enterblock(fs, &bl, 1);  /* scope for loop and control variables */
+  luaX_next(ls);  /* skip 'for' */
+  varname = str_checkname(ls);  /* first variable name */
+  switch (ls->t.token) {
+    case '=': fornum(ls, varname, line); break;
+    case ',': case TK_IN: forlist(ls, varname); break;
+    default: luaX_syntaxerror(ls, "'=' or 'in' expected");
+  }
+  check_match(ls, TK_END, TK_FOR, line);
+  leaveblock(fs);  /* loop scope ('break' jumps to this point) */
+}
+
+
+/*
+** Check whether next instruction is a single jump (a 'break', a 'goto'
+** to a forward label, or a 'goto' to a backward label with no variable
+** to close). If so, set the name of the 'label' it is jumping to
+** ("break" for a 'break') or to where it is jumping to ('target') and
+** return true. If not a single jump, leave input unchanged, to be
+** handled as a regular statement.
+*/
+static int issinglejump (LexState *ls, TString **label, int *target) {
+  if (testnext(ls, TK_BREAK)) {  /* a break? */
+    *label = luaS_newliteral(ls->L, "break");
+    return 1;
+  }
+  else if (ls->t.token != TK_GOTO || luaX_lookahead(ls) != TK_NAME)
+    return 0;  /* not a valid goto */
+  else {
+    TString *lname = ls->lookahead.seminfo.ts;  /* label's id */
+    Labeldesc *lb = findlabel(ls, lname);
+    if (lb) {  /* a backward jump? */
+      /* does it need to close variables? */
+      if (luaY_nvarstack(ls->fs) > stacklevel(ls->fs, lb->nactvar))
+        return 0;  /* not a single jump; cannot optimize */
+      *target = lb->pc;
+    }
+    else  /* jump forward */
+      *label = lname;
+    luaX_next(ls);  /* skip goto */
+    luaX_next(ls);  /* skip name */
+    return 1;
+  }
+}
+
+
+static void test_then_block (LexState *ls, int *escapelist) {
+  /* test_then_block -> [IF | ELSEIF] cond THEN block */
+  BlockCnt bl;
+  int line;
+  FuncState *fs = ls->fs;
+  TString *jlb = NULL;
+  int target = NO_JUMP;
+  expdesc v;
+  int jf;  /* instruction to skip 'then' code (if condition is false) */
+  luaX_next(ls);  /* skip IF or ELSEIF */
+  expr(ls, &v);  /* read condition */
+  checknext(ls, TK_THEN);
+  line = ls->linenumber;
+  if (issinglejump(ls, &jlb, &target)) {  /* 'if x then goto' ? */
+    luaK_goiffalse(ls->fs, &v);  /* will jump to label if condition is true */
+    enterblock(fs, &bl, 0);  /* must enter block before 'goto' */
+    if (jlb != NULL)  /* forward jump? */
+      newgotoentry(ls, jlb, line, v.t);  /* will be resolved later */
+    else  /* backward jump */
+      luaK_patchlist(fs, v.t, target);  /* jump directly to 'target' */
+    while (testnext(ls, ';')) {}  /* skip semicolons */
+    if (block_follow(ls, 0)) {  /* jump is the entire block? */
+      leaveblock(fs);
+      return;  /* and that is it */
+    }
+    else  /* must skip over 'then' part if condition is false */
+      jf = luaK_jump(fs);
+  }
+  else {  /* regular case (not a jump) */
+    luaK_goiftrue(ls->fs, &v);  /* skip over block if condition is false */
+    enterblock(fs, &bl, 0);
+    jf = v.f;
+  }
+  statlist(ls);  /* 'then' part */
+  leaveblock(fs);
+  if (ls->t.token == TK_ELSE ||
+      ls->t.token == TK_ELSEIF)  /* followed by 'else'/'elseif'? */
+    luaK_concat(fs, escapelist, luaK_jump(fs));  /* must jump over it */
+  luaK_patchtohere(fs, jf);
+}
+
+
+static void ifstat (LexState *ls, int line) {
+  /* ifstat -> IF cond THEN block {ELSEIF cond THEN block} [ELSE block] END */
+  FuncState *fs = ls->fs;
+  int escapelist = NO_JUMP;  /* exit list for finished parts */
+  test_then_block(ls, &escapelist);  /* IF cond THEN block */
+  while (ls->t.token == TK_ELSEIF)
+    test_then_block(ls, &escapelist);  /* ELSEIF cond THEN block */
+  if (testnext(ls, TK_ELSE))
+    block(ls);  /* 'else' part */
+  check_match(ls, TK_END, TK_IF, line);
+  luaK_patchtohere(fs, escapelist);  /* patch escape list to 'if' end */
+}
+
+
+static void localfunc (LexState *ls) {
+  expdesc b;
+  FuncState *fs = ls->fs;
+  int fvar = fs->nactvar;  /* function's variable index */
+  new_localvar(ls, str_checkname(ls));  /* new local variable */
+  adjustlocalvars(ls, 1);  /* enter its scope */
+  body(ls, &b, 0, ls->linenumber);  /* function created in next register */
+  /* debug information will only see the variable after this point! */
+  localdebuginfo(fs, fvar)->startpc = fs->pc;
+}
+
+
+static int getlocalattribute (LexState *ls) {
+  /* ATTRIB -> ['<' Name '>'] */
+  if (testnext(ls, '<')) {
+    const char *attr = getstr(str_checkname(ls));
+    checknext(ls, '>');
+    if (strcmp(attr, "const") == 0)
+      return RDKCONST;  /* read-only variable */
+    else if (strcmp(attr, "close") == 0)
+      return RDKTOCLOSE;  /* to-be-closed variable */
+    else
+      luaK_semerror(ls,
+        luaO_pushfstring(ls->L, "unknown attribute '%s'", attr));
+  }
+  return VDKREG;  /* regular variable */
+}
+
+
+static void checktoclose (LexState *ls, int level) {
+  if (level != -1) {  /* is there a to-be-closed variable? */
+    FuncState *fs = ls->fs;
+    markupval(fs, level + 1);
+    fs->bl->insidetbc = 1;  /* in the scope of a to-be-closed variable */
+    luaK_codeABC(fs, OP_TBC, stacklevel(fs, level), 0, 0);
+  }
+}
+
+
+static void localstat (LexState *ls) {
+  /* stat -> LOCAL ATTRIB NAME {',' ATTRIB NAME} ['=' explist] */
+  FuncState *fs = ls->fs;
+  int toclose = -1;  /* index of to-be-closed variable (if any) */
+  Vardesc *var;  /* last variable */
+  int vidx, kind;  /* index and kind of last variable */
+  int nvars = 0;
+  int nexps;
+  expdesc e;
+  do {
+    vidx = new_localvar(ls, str_checkname(ls));
+    kind = getlocalattribute(ls);
+    getlocalvardesc(fs, vidx)->vd.kind = kind;
+    if (kind == RDKTOCLOSE) {  /* to-be-closed? */
+      if (toclose != -1)  /* one already present? */
+        luaK_semerror(ls, "multiple to-be-closed variables in local list");
+      toclose = fs->nactvar + nvars;
+    }
+    nvars++;
+  } while (testnext(ls, ','));
+  if (testnext(ls, '='))
+    nexps = explist(ls, &e);
+  else {
+    e.k = VVOID;
+    nexps = 0;
+  }
+  var = getlocalvardesc(fs, vidx);  /* get last variable */
+  if (nvars == nexps &&  /* no adjustments? */
+      var->vd.kind == RDKCONST &&  /* last variable is const? */
+      luaK_exp2const(fs, &e, &var->k)) {  /* compile-time constant? */
+    var->vd.kind = RDKCTC;  /* variable is a compile-time constant */
+    adjustlocalvars(ls, nvars - 1);  /* exclude last variable */
+    fs->nactvar++;  /* but count it */
+  }
+  else {
+    adjust_assign(ls, nvars, nexps, &e);
+    adjustlocalvars(ls, nvars);
+  }
+  checktoclose(ls, toclose);
+}
+
+
+static int funcname (LexState *ls, expdesc *v) {
+  /* funcname -> NAME {fieldsel} [':' NAME] */
+  int ismethod = 0;
+  singlevar(ls, v);
+  while (ls->t.token == '.')
+    fieldsel(ls, v);
+  if (ls->t.token == ':') {
+    ismethod = 1;
+    fieldsel(ls, v);
+  }
+  return ismethod;
+}
+
+
+static void funcstat (LexState *ls, int line) {
+  /* funcstat -> FUNCTION funcname body */
+  int ismethod;
+  expdesc v, b;
+  luaX_next(ls);  /* skip FUNCTION */
+  ismethod = funcname(ls, &v);
+  body(ls, &b, ismethod, line);
+  luaK_storevar(ls->fs, &v, &b);
+  luaK_fixline(ls->fs, line);  /* definition "happens" in the first line */
+}
+
+
+static void exprstat (LexState *ls) {
+  /* stat -> func | assignment */
+  FuncState *fs = ls->fs;
+  struct LHS_assign v;
+  suffixedexp(ls, &v.v);
+  if (ls->t.token == '=' || ls->t.token == ',') { /* stat -> assignment ? */
+    v.prev = NULL;
+    restassign(ls, &v, 1);
+  }
+  else {  /* stat -> func */
+    Instruction *inst;
+    check_condition(ls, v.v.k == VCALL, "syntax error");
+    inst = &getinstruction(fs, &v.v);
+    SETARG_C(*inst, 1);  /* call statement uses no results */
+  }
+}
+
+
+static void retstat (LexState *ls) {
+  /* stat -> RETURN [explist] [';'] */
+  FuncState *fs = ls->fs;
+  expdesc e;
+  int nret;  /* number of values being returned */
+  int first = luaY_nvarstack(fs);  /* first slot to be returned */
+  if (block_follow(ls, 1) || ls->t.token == ';')
+    nret = 0;  /* return no values */
+  else {
+    nret = explist(ls, &e);  /* optional return values */
+    if (hasmultret(e.k)) {
+      luaK_setmultret(fs, &e);
+      if (e.k == VCALL && nret == 1 && !fs->bl->insidetbc) {  /* tail call? */
+        SET_OPCODE(getinstruction(fs,&e), OP_TAILCALL);
+        lua_assert(GETARG_A(getinstruction(fs,&e)) == luaY_nvarstack(fs));
+      }
+      nret = LUA_MULTRET;  /* return all values */
+    }
+    else {
+      if (nret == 1)  /* only one single value? */
+        first = luaK_exp2anyreg(fs, &e);  /* can use original slot */
+      else {  /* values must go to the top of the stack */
+        luaK_exp2nextreg(fs, &e);
+        lua_assert(nret == fs->freereg - first);
+      }
+    }
+  }
+  luaK_ret(fs, first, nret);
+  testnext(ls, ';');  /* skip optional semicolon */
+}
+
+
+static void statement (LexState *ls) {
+  int line = ls->linenumber;  /* may be needed for error messages */
+  enterlevel(ls);
+  switch (ls->t.token) {
+    case ';': {  /* stat -> ';' (empty statement) */
+      luaX_next(ls);  /* skip ';' */
+      break;
+    }
+    case TK_IF: {  /* stat -> ifstat */
+      ifstat(ls, line);
+      break;
+    }
+    case TK_WHILE: {  /* stat -> whilestat */
+      whilestat(ls, line);
+      break;
+    }
+    case TK_DO: {  /* stat -> DO block END */
+      luaX_next(ls);  /* skip DO */
+      block(ls);
+      check_match(ls, TK_END, TK_DO, line);
+      break;
+    }
+    case TK_FOR: {  /* stat -> forstat */
+      forstat(ls, line);
+      break;
+    }
+    case TK_REPEAT: {  /* stat -> repeatstat */
+      repeatstat(ls, line);
+      break;
+    }
+    case TK_FUNCTION: {  /* stat -> funcstat */
+      funcstat(ls, line);
+      break;
+    }
+    case TK_LOCAL: {  /* stat -> localstat */
+      luaX_next(ls);  /* skip LOCAL */
+      if (testnext(ls, TK_FUNCTION))  /* local function? */
+        localfunc(ls);
+      else
+        localstat(ls);
+      break;
+    }
+    case TK_DBCOLON: {  /* stat -> label */
+      luaX_next(ls);  /* skip double colon */
+      labelstat(ls, str_checkname(ls), line);
+      break;
+    }
+    case TK_RETURN: {  /* stat -> retstat */
+      luaX_next(ls);  /* skip RETURN */
+      retstat(ls);
+      break;
+    }
+    case TK_BREAK: {  /* stat -> breakstat */
+      breakstat(ls);
+      break;
+    }
+    case TK_GOTO: {  /* stat -> 'goto' NAME */
+      luaX_next(ls);  /* skip 'goto' */
+      gotostat(ls);
+      break;
+    }
+    default: {  /* stat -> func | assignment */
+      exprstat(ls);
+      break;
+    }
+  }
+  lua_assert(ls->fs->f->maxstacksize >= ls->fs->freereg &&
+             ls->fs->freereg >= luaY_nvarstack(ls->fs));
+  ls->fs->freereg = luaY_nvarstack(ls->fs);  /* free registers */
+  leavelevel(ls);
+}
+
+/* }====================================================================== */
+
+
+/*
+** compiles the main function, which is a regular vararg function with an
+** upvalue named LUA_ENV
+*/
+static void mainfunc (LexState *ls, FuncState *fs) {
+  BlockCnt bl;
+  Upvaldesc *env;
+  open_func(ls, fs, &bl);
+  setvararg(fs, 0);  /* main function is always declared vararg */
+  env = allocupvalue(fs);  /* ...set environment upvalue */
+  env->instack = 1;
+  env->idx = 0;
+  env->kind = VDKREG;
+  env->name = ls->envn;
+  luaC_objbarrier(ls->L, fs->f, env->name);
+  luaX_next(ls);  /* read first token */
+  statlist(ls);  /* parse main body */
+  check(ls, TK_EOS);
+  close_func(ls);
+}
+
+
+LClosure *luaY_parser (lua_State *L, ZIO *z, Mbuffer *buff,
+                       Dyndata *dyd, const char *name, int firstchar) {
+  LexState lexstate;
+  FuncState funcstate;
+  LClosure *cl = luaF_newLclosure(L, 1);  /* create main closure */
+  setclLvalue2s(L, L->top, cl);  /* anchor it (to avoid being collected) */
+  luaD_inctop(L);
+  lexstate.h = luaH_new(L);  /* create table for scanner */
+  sethvalue2s(L, L->top, lexstate.h);  /* anchor it */
+  luaD_inctop(L);
+  funcstate.f = cl->p = luaF_newproto(L);
+  luaC_objbarrier(L, cl, cl->p);
+  funcstate.f->source = luaS_new(L, name);  /* create and anchor TString */
+  luaC_objbarrier(L, funcstate.f, funcstate.f->source);
+  lexstate.buff = buff;
+  lexstate.dyd = dyd;
+  dyd->actvar.n = dyd->gt.n = dyd->label.n = 0;
+  luaX_setinput(L, &lexstate, z, funcstate.f->source, firstchar);
+  mainfunc(&lexstate, &funcstate);
+  lua_assert(!funcstate.prev && funcstate.nups == 1 && !lexstate.fs);
+  /* all scopes should be correctly finished */
+  lua_assert(dyd->actvar.n == 0 && dyd->gt.n == 0 && dyd->label.n == 0);
+  L->top--;  /* remove scanner's table */
+  return cl;  /* closure is on the stack, too */
+}
+
diff --git a/test/external/lua-5.4.0/src/lparser.h b/test/external/lua-5.4.0/src/lparser.h
new file mode 100644
index 0000000..618cb01
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lparser.h
@@ -0,0 +1,170 @@
+/*
+** $Id: lparser.h $
+** Lua Parser
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lparser_h
+#define lparser_h
+
+#include "llimits.h"
+#include "lobject.h"
+#include "lzio.h"
+
+
+/*
+** Expression and variable descriptor.
+** Code generation for variables and expressions can be delayed to allow
+** optimizations; An 'expdesc' structure describes a potentially-delayed
+** variable/expression. It has a description of its "main" value plus a
+** list of conditional jumps that can also produce its value (generated
+** by short-circuit operators 'and'/'or').
+*/
+
+/* kinds of variables/expressions */
+typedef enum {
+  VVOID,  /* when 'expdesc' describes the last expression a list,
+             this kind means an empty list (so, no expression) */
+  VNIL,  /* constant nil */
+  VTRUE,  /* constant true */
+  VFALSE,  /* constant false */
+  VK,  /* constant in 'k'; info = index of constant in 'k' */
+  VKFLT,  /* floating constant; nval = numerical float value */
+  VKINT,  /* integer constant; ival = numerical integer value */
+  VKSTR,  /* string constant; strval = TString address;
+             (string is fixed by the lexer) */
+  VNONRELOC,  /* expression has its value in a fixed register;
+                 info = result register */
+  VLOCAL,  /* local variable; var.sidx = stack index (local register);
+              var.vidx = relative index in 'actvar.arr'  */
+  VUPVAL,  /* upvalue variable; info = index of upvalue in 'upvalues' */
+  VCONST,  /* compile-time constant; info = absolute index in 'actvar.arr'  */
+  VINDEXED,  /* indexed variable;
+                ind.t = table register;
+                ind.idx = key's R index */
+  VINDEXUP,  /* indexed upvalue;
+                ind.t = table upvalue;
+                ind.idx = key's K index */
+  VINDEXI, /* indexed variable with constant integer;
+                ind.t = table register;
+                ind.idx = key's value */
+  VINDEXSTR, /* indexed variable with literal string;
+                ind.t = table register;
+                ind.idx = key's K index */
+  VJMP,  /* expression is a test/comparison;
+            info = pc of corresponding jump instruction */
+  VRELOC,  /* expression can put result in any register;
+              info = instruction pc */
+  VCALL,  /* expression is a function call; info = instruction pc */
+  VVARARG  /* vararg expression; info = instruction pc */
+} expkind;
+
+
+#define vkisvar(k)	(VLOCAL <= (k) && (k) <= VINDEXSTR)
+#define vkisindexed(k)	(VINDEXED <= (k) && (k) <= VINDEXSTR)
+
+
+typedef struct expdesc {
+  expkind k;
+  union {
+    lua_Integer ival;    /* for VKINT */
+    lua_Number nval;  /* for VKFLT */
+    TString *strval;  /* for VKSTR */
+    int info;  /* for generic use */
+    struct {  /* for indexed variables */
+      short idx;  /* index (R or "long" K) */
+      lu_byte t;  /* table (register or upvalue) */
+    } ind;
+    struct {  /* for local variables */
+      lu_byte sidx;  /* index in the stack */
+      unsigned short vidx;  /* compiler index (in 'actvar.arr')  */
+    } var;
+  } u;
+  int t;  /* patch list of 'exit when true' */
+  int f;  /* patch list of 'exit when false' */
+} expdesc;
+
+
+/* kinds of variables */
+#define VDKREG		0   /* regular */
+#define RDKCONST	1   /* constant */
+#define RDKTOCLOSE	2   /* to-be-closed */
+#define RDKCTC		3   /* compile-time constant */
+
+/* description of an active local variable */
+typedef union Vardesc {
+  struct {
+    TValuefields;  /* constant value (if it is a compile-time constant) */
+    lu_byte kind;
+    lu_byte sidx;  /* index of the variable in the stack */
+    short pidx;  /* index of the variable in the Proto's 'locvars' array */
+    TString *name;  /* variable name */
+  } vd;
+  TValue k;  /* constant value (if any) */
+} Vardesc;
+
+
+
+/* description of pending goto statements and label statements */
+typedef struct Labeldesc {
+  TString *name;  /* label identifier */
+  int pc;  /* position in code */
+  int line;  /* line where it appeared */
+  lu_byte nactvar;  /* number of active variables in that position */
+  lu_byte close;  /* goto that escapes upvalues */
+} Labeldesc;
+
+
+/* list of labels or gotos */
+typedef struct Labellist {
+  Labeldesc *arr;  /* array */
+  int n;  /* number of entries in use */
+  int size;  /* array size */
+} Labellist;
+
+
+/* dynamic structures used by the parser */
+typedef struct Dyndata {
+  struct {  /* list of all active local variables */
+    Vardesc *arr;
+    int n;
+    int size;
+  } actvar;
+  Labellist gt;  /* list of pending gotos */
+  Labellist label;   /* list of active labels */
+} Dyndata;
+
+
+/* control of blocks */
+struct BlockCnt;  /* defined in lparser.c */
+
+
+/* state needed to generate code for a given function */
+typedef struct FuncState {
+  Proto *f;  /* current function header */
+  struct FuncState *prev;  /* enclosing function */
+  struct LexState *ls;  /* lexical state */
+  struct BlockCnt *bl;  /* chain of current blocks */
+  int pc;  /* next position to code (equivalent to 'ncode') */
+  int lasttarget;   /* 'label' of last 'jump label' */
+  int previousline;  /* last line that was saved in 'lineinfo' */
+  int nk;  /* number of elements in 'k' */
+  int np;  /* number of elements in 'p' */
+  int nabslineinfo;  /* number of elements in 'abslineinfo' */
+  int firstlocal;  /* index of first local var (in Dyndata array) */
+  int firstlabel;  /* index of first label (in 'dyd->label->arr') */
+  short ndebugvars;  /* number of elements in 'f->locvars' */
+  lu_byte nactvar;  /* number of active local variables */
+  lu_byte nups;  /* number of upvalues */
+  lu_byte freereg;  /* first free register */
+  lu_byte iwthabs;  /* instructions issued since last absolute line info */
+  lu_byte needclose;  /* function needs to close upvalues when returning */
+} FuncState;
+
+
+LUAI_FUNC int luaY_nvarstack (FuncState *fs);
+LUAI_FUNC LClosure *luaY_parser (lua_State *L, ZIO *z, Mbuffer *buff,
+                                 Dyndata *dyd, const char *name, int firstchar);
+
+
+#endif
diff --git a/test/external/lua-5.4.0/src/lprefix.h b/test/external/lua-5.4.0/src/lprefix.h
new file mode 100644
index 0000000..484f2ad
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lprefix.h
@@ -0,0 +1,45 @@
+/*
+** $Id: lprefix.h $
+** Definitions for Lua code that must come before any other header file
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lprefix_h
+#define lprefix_h
+
+
+/*
+** Allows POSIX/XSI stuff
+*/
+#if !defined(LUA_USE_C89)	/* { */
+
+#if !defined(_XOPEN_SOURCE)
+#define _XOPEN_SOURCE           600
+#elif _XOPEN_SOURCE == 0
+#undef _XOPEN_SOURCE  /* use -D_XOPEN_SOURCE=0 to undefine it */
+#endif
+
+/*
+** Allows manipulation of large files in gcc and some other compilers
+*/
+#if !defined(LUA_32BITS) && !defined(_FILE_OFFSET_BITS)
+#define _LARGEFILE_SOURCE       1
+#define _FILE_OFFSET_BITS       64
+#endif
+
+#endif				/* } */
+
+
+/*
+** Windows stuff
+*/
+#if defined(_WIN32)	/* { */
+
+#if !defined(_CRT_SECURE_NO_WARNINGS)
+#define _CRT_SECURE_NO_WARNINGS  /* avoid warnings about ISO C functions */
+#endif
+
+#endif			/* } */
+
+#endif
+
diff --git a/test/external/lua-5.4.0/src/lstate.c b/test/external/lua-5.4.0/src/lstate.c
new file mode 100644
index 0000000..4434211
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lstate.c
@@ -0,0 +1,467 @@
+/*
+** $Id: lstate.c $
+** Global State
+** See Copyright Notice in lua.h
+*/
+
+#define lstate_c
+#define LUA_CORE
+
+#include "lprefix.h"
+
+
+#include <stddef.h>
+#include <string.h>
+
+#include "lua.h"
+
+#include "lapi.h"
+#include "ldebug.h"
+#include "ldo.h"
+#include "lfunc.h"
+#include "lgc.h"
+#include "llex.h"
+#include "lmem.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "ltm.h"
+
+
+
+/*
+** thread state + extra space
+*/
+typedef struct LX {
+  lu_byte extra_[LUA_EXTRASPACE];
+  lua_State l;
+} LX;
+
+
+/*
+** Main thread combines a thread state and the global state
+*/
+typedef struct LG {
+  LX l;
+  global_State g;
+} LG;
+
+
+
+#define fromstate(L)	(cast(LX *, cast(lu_byte *, (L)) - offsetof(LX, l)))
+
+
+/*
+** A macro to create a "random" seed when a state is created;
+** the seed is used to randomize string hashes.
+*/
+#if !defined(luai_makeseed)
+
+#include <time.h>
+
+/*
+** Compute an initial seed with some level of randomness.
+** Rely on Address Space Layout Randomization (if present) and
+** current time.
+*/
+#define addbuff(b,p,e) \
+  { size_t t = cast_sizet(e); \
+    memcpy(b + p, &t, sizeof(t)); p += sizeof(t); }
+
+static unsigned int luai_makeseed (lua_State *L) {
+  char buff[3 * sizeof(size_t)];
+  unsigned int h = cast_uint(time(NULL));
+  int p = 0;
+  addbuff(buff, p, L);  /* heap variable */
+  addbuff(buff, p, &h);  /* local variable */
+  addbuff(buff, p, &lua_newstate);  /* public function */
+  lua_assert(p == sizeof(buff));
+  return luaS_hash(buff, p, h, 1);
+}
+
+#endif
+
+
+/*
+** set GCdebt to a new value keeping the value (totalbytes + GCdebt)
+** invariant (and avoiding underflows in 'totalbytes')
+*/
+void luaE_setdebt (global_State *g, l_mem debt) {
+  l_mem tb = gettotalbytes(g);
+  lua_assert(tb > 0);
+  if (debt < tb - MAX_LMEM)
+    debt = tb - MAX_LMEM;  /* will make 'totalbytes == MAX_LMEM' */
+  g->totalbytes = tb - debt;
+  g->GCdebt = debt;
+}
+
+
+LUA_API int lua_setcstacklimit (lua_State *L, unsigned int limit) {
+  global_State *g = G(L);
+  int ccalls;
+  luaE_freeCI(L);  /* release unused CIs */
+  ccalls = getCcalls(L);
+  if (limit >= 40000)
+    return 0;  /* out of bounds */
+  limit += CSTACKERR;
+  if (L != g-> mainthread)
+    return 0;  /* only main thread can change the C stack */
+  else if (ccalls <= CSTACKERR)
+    return 0;  /* handling overflow */
+  else {
+    int diff = limit - g->Cstacklimit;
+    if (ccalls + diff <= CSTACKERR)
+      return 0;  /* new limit would cause an overflow */
+    g->Cstacklimit = limit;  /* set new limit */
+    L->nCcalls += diff;  /* correct 'nCcalls' */
+    return limit - diff - CSTACKERR;  /* success; return previous limit */
+  }
+}
+
+
+/*
+** Decrement count of "C calls" and check for overflows. In case of
+** a stack overflow, check appropriate error ("regular" overflow or
+** overflow while handling stack overflow).  If 'nCcalls' is smaller
+** than CSTACKERR but larger than CSTACKMARK, it means it has just
+** entered the "overflow zone", so the function raises an overflow
+** error.  If 'nCcalls' is smaller than CSTACKMARK (which means it is
+** already handling an overflow) but larger than CSTACKERRMARK, does
+** not report an error (to allow message handling to work). Otherwise,
+** report a stack overflow while handling a stack overflow (probably
+** caused by a repeating error in the message handling function).
+*/
+
+void luaE_enterCcall (lua_State *L) {
+  int ncalls = getCcalls(L);
+  L->nCcalls--;
+  if (ncalls <= CSTACKERR) {  /* possible overflow? */
+    luaE_freeCI(L);  /* release unused CIs */
+    ncalls = getCcalls(L);  /* update call count */
+    if (ncalls <= CSTACKERR) {  /* still overflow? */
+      if (ncalls <= CSTACKERRMARK)  /* below error-handling zone? */
+        luaD_throw(L, LUA_ERRERR);  /* error while handling stack error */
+      else if (ncalls >= CSTACKMARK) {
+        /* not in error-handling zone; raise the error now */
+        L->nCcalls = (CSTACKMARK - 1);  /* enter error-handling zone */
+        luaG_runerror(L, "C stack overflow");
+      }
+      /* else stack is in the error-handling zone;
+         allow message handler to work */
+    }
+  }
+}
+
+
+CallInfo *luaE_extendCI (lua_State *L) {
+  CallInfo *ci;
+  lua_assert(L->ci->next == NULL);
+  luaE_enterCcall(L);
+  ci = luaM_new(L, CallInfo);
+  lua_assert(L->ci->next == NULL);
+  L->ci->next = ci;
+  ci->previous = L->ci;
+  ci->next = NULL;
+  ci->u.l.trap = 0;
+  L->nci++;
+  return ci;
+}
+
+
+/*
+** free all CallInfo structures not in use by a thread
+*/
+void luaE_freeCI (lua_State *L) {
+  CallInfo *ci = L->ci;
+  CallInfo *next = ci->next;
+  ci->next = NULL;
+  L->nCcalls += L->nci;  /* add removed elements back to 'nCcalls' */
+  while ((ci = next) != NULL) {
+    next = ci->next;
+    luaM_free(L, ci);
+    L->nci--;
+  }
+  L->nCcalls -= L->nci;  /* adjust result */
+}
+
+
+/*
+** free half of the CallInfo structures not in use by a thread,
+** keeping the first one.
+*/
+void luaE_shrinkCI (lua_State *L) {
+  CallInfo *ci = L->ci->next;  /* first free CallInfo */
+  CallInfo *next;
+  if (ci == NULL)
+    return;  /* no extra elements */
+  L->nCcalls += L->nci;  /* add removed elements back to 'nCcalls' */
+  while ((next = ci->next) != NULL) {  /* two extra elements? */
+    CallInfo *next2 = next->next;  /* next's next */
+    ci->next = next2;  /* remove next from the list */
+    L->nci--;
+    luaM_free(L, next);  /* free next */
+    if (next2 == NULL)
+      break;  /* no more elements */
+    else {
+      next2->previous = ci;
+      ci = next2;  /* continue */
+    }
+  }
+  L->nCcalls -= L->nci;  /* adjust result */
+}
+
+
+static void stack_init (lua_State *L1, lua_State *L) {
+  int i; CallInfo *ci;
+  /* initialize stack array */
+  L1->stack = luaM_newvector(L, BASIC_STACK_SIZE, StackValue);
+  L1->stacksize = BASIC_STACK_SIZE;
+  for (i = 0; i < BASIC_STACK_SIZE; i++)
+    setnilvalue(s2v(L1->stack + i));  /* erase new stack */
+  L1->top = L1->stack;
+  L1->stack_last = L1->stack + L1->stacksize - EXTRA_STACK;
+  /* initialize first ci */
+  ci = &L1->base_ci;
+  ci->next = ci->previous = NULL;
+  ci->callstatus = CIST_C;
+  ci->func = L1->top;
+  ci->u.c.k = NULL;
+  ci->nresults = 0;
+  setnilvalue(s2v(L1->top));  /* 'function' entry for this 'ci' */
+  L1->top++;
+  ci->top = L1->top + LUA_MINSTACK;
+  L1->ci = ci;
+}
+
+
+static void freestack (lua_State *L) {
+  if (L->stack == NULL)
+    return;  /* stack not completely built yet */
+  L->ci = &L->base_ci;  /* free the entire 'ci' list */
+  luaE_freeCI(L);
+  lua_assert(L->nci == 0);
+  luaM_freearray(L, L->stack, L->stacksize);  /* free stack array */
+}
+
+
+/*
+** Create registry table and its predefined values
+*/
+static void init_registry (lua_State *L, global_State *g) {
+  TValue temp;
+  /* create registry */
+  Table *registry = luaH_new(L);
+  sethvalue(L, &g->l_registry, registry);
+  luaH_resize(L, registry, LUA_RIDX_LAST, 0);
+  /* registry[LUA_RIDX_MAINTHREAD] = L */
+  setthvalue(L, &temp, L);  /* temp = L */
+  luaH_setint(L, registry, LUA_RIDX_MAINTHREAD, &temp);
+  /* registry[LUA_RIDX_GLOBALS] = table of globals */
+  sethvalue(L, &temp, luaH_new(L));  /* temp = new table (global table) */
+  luaH_setint(L, registry, LUA_RIDX_GLOBALS, &temp);
+}
+
+
+/*
+** open parts of the state that may cause memory-allocation errors.
+** ('g->nilvalue' being a nil value flags that the state was completely
+** build.)
+*/
+static void f_luaopen (lua_State *L, void *ud) {
+  global_State *g = G(L);
+  UNUSED(ud);
+  stack_init(L, L);  /* init stack */
+  init_registry(L, g);
+  luaS_init(L);
+  luaT_init(L);
+  luaX_init(L);
+  g->gcrunning = 1;  /* allow gc */
+  setnilvalue(&g->nilvalue);
+  luai_userstateopen(L);
+}
+
+
+/*
+** preinitialize a thread with consistent values without allocating
+** any memory (to avoid errors)
+*/
+static void preinit_thread (lua_State *L, global_State *g) {
+  G(L) = g;
+  L->stack = NULL;
+  L->ci = NULL;
+  L->nci = 0;
+  L->stacksize = 0;
+  L->twups = L;  /* thread has no upvalues */
+  L->errorJmp = NULL;
+  L->hook = NULL;
+  L->hookmask = 0;
+  L->basehookcount = 0;
+  L->allowhook = 1;
+  resethookcount(L);
+  L->openupval = NULL;
+  L->status = LUA_OK;
+  L->errfunc = 0;
+}
+
+
+static void close_state (lua_State *L) {
+  global_State *g = G(L);
+  luaF_close(L, L->stack, CLOSEPROTECT);  /* close all upvalues */
+  luaC_freeallobjects(L);  /* collect all objects */
+  if (ttisnil(&g->nilvalue))  /* closing a fully built state? */
+    luai_userstateclose(L);
+  luaM_freearray(L, G(L)->strt.hash, G(L)->strt.size);
+  freestack(L);
+  lua_assert(gettotalbytes(g) == sizeof(LG));
+  (*g->frealloc)(g->ud, fromstate(L), sizeof(LG), 0);  /* free main block */
+}
+
+
+LUA_API lua_State *lua_newthread (lua_State *L) {
+  global_State *g = G(L);
+  lua_State *L1;
+  lua_lock(L);
+  luaC_checkGC(L);
+  /* create new thread */
+  L1 = &cast(LX *, luaM_newobject(L, LUA_TTHREAD, sizeof(LX)))->l;
+  L1->marked = luaC_white(g);
+  L1->tt = LUA_VTHREAD;
+  /* link it on list 'allgc' */
+  L1->next = g->allgc;
+  g->allgc = obj2gco(L1);
+  /* anchor it on L stack */
+  setthvalue2s(L, L->top, L1);
+  api_incr_top(L);
+  preinit_thread(L1, g);
+  L1->nCcalls = getCcalls(L);
+  L1->hookmask = L->hookmask;
+  L1->basehookcount = L->basehookcount;
+  L1->hook = L->hook;
+  resethookcount(L1);
+  /* initialize L1 extra space */
+  memcpy(lua_getextraspace(L1), lua_getextraspace(g->mainthread),
+         LUA_EXTRASPACE);
+  luai_userstatethread(L, L1);
+  stack_init(L1, L);  /* init stack */
+  lua_unlock(L);
+  return L1;
+}
+
+
+void luaE_freethread (lua_State *L, lua_State *L1) {
+  LX *l = fromstate(L1);
+  luaF_close(L1, L1->stack, NOCLOSINGMETH);  /* close all upvalues */
+  lua_assert(L1->openupval == NULL);
+  luai_userstatefree(L, L1);
+  freestack(L1);
+  luaM_free(L, l);
+}
+
+
+int lua_resetthread (lua_State *L) {
+  CallInfo *ci;
+  int status;
+  lua_lock(L);
+  L->ci = ci = &L->base_ci;  /* unwind CallInfo list */
+  setnilvalue(s2v(L->stack));  /* 'function' entry for basic 'ci' */
+  ci->func = L->stack;
+  ci->callstatus = CIST_C;
+  status = luaF_close(L, L->stack, CLOSEPROTECT);
+  if (status != CLOSEPROTECT)  /* real errors? */
+    luaD_seterrorobj(L, status, L->stack + 1);
+  else {
+    status = LUA_OK;
+    L->top = L->stack + 1;
+  }
+  ci->top = L->top + LUA_MINSTACK;
+  L->status = status;
+  lua_unlock(L);
+  return status;
+}
+
+
+LUA_API lua_State *lua_newstate (lua_Alloc f, void *ud) {
+  int i;
+  lua_State *L;
+  global_State *g;
+  LG *l = cast(LG *, (*f)(ud, NULL, LUA_TTHREAD, sizeof(LG)));
+  if (l == NULL) return NULL;
+  L = &l->l.l;
+  g = &l->g;
+  L->tt = LUA_VTHREAD;
+  g->currentwhite = bitmask(WHITE0BIT);
+  L->marked = luaC_white(g);
+  preinit_thread(L, g);
+  g->allgc = obj2gco(L);  /* by now, only object is the main thread */
+  L->next = NULL;
+  g->Cstacklimit = L->nCcalls = LUAI_MAXCSTACK + CSTACKERR;
+  g->frealloc = f;
+  g->ud = ud;
+  g->warnf = NULL;
+  g->ud_warn = NULL;
+  g->mainthread = L;
+  g->seed = luai_makeseed(L);
+  g->gcrunning = 0;  /* no GC while building state */
+  g->strt.size = g->strt.nuse = 0;
+  g->strt.hash = NULL;
+  setnilvalue(&g->l_registry);
+  g->panic = NULL;
+  g->gcstate = GCSpause;
+  g->gckind = KGC_INC;
+  g->gcemergency = 0;
+  g->finobj = g->tobefnz = g->fixedgc = NULL;
+  g->survival = g->old = g->reallyold = NULL;
+  g->finobjsur = g->finobjold = g->finobjrold = NULL;
+  g->sweepgc = NULL;
+  g->gray = g->grayagain = NULL;
+  g->weak = g->ephemeron = g->allweak = NULL;
+  g->twups = NULL;
+  g->totalbytes = sizeof(LG);
+  g->GCdebt = 0;
+  g->lastatomic = 0;
+  setivalue(&g->nilvalue, 0);  /* to signal that state is not yet built */
+  setgcparam(g->gcpause, LUAI_GCPAUSE);
+  setgcparam(g->gcstepmul, LUAI_GCMUL);
+  g->gcstepsize = LUAI_GCSTEPSIZE;
+  setgcparam(g->genmajormul, LUAI_GENMAJORMUL);
+  g->genminormul = LUAI_GENMINORMUL;
+  for (i=0; i < LUA_NUMTAGS; i++) g->mt[i] = NULL;
+  if (luaD_rawrunprotected(L, f_luaopen, NULL) != LUA_OK) {
+    /* memory allocation error: free partial state */
+    close_state(L);
+    L = NULL;
+  }
+  return L;
+}
+
+
+LUA_API void lua_close (lua_State *L) {
+  L = G(L)->mainthread;  /* only the main thread can be closed */
+  lua_lock(L);
+  close_state(L);
+}
+
+
+void luaE_warning (lua_State *L, const char *msg, int tocont) {
+  lua_WarnFunction wf = G(L)->warnf;
+  if (wf != NULL)
+    wf(G(L)->ud_warn, msg, tocont);
+}
+
+
+/*
+** Generate a warning from an error message
+*/
+void luaE_warnerror (lua_State *L, const char *where) {
+  TValue *errobj = s2v(L->top - 1);  /* error object */
+  const char *msg = (ttisstring(errobj))
+                  ? svalue(errobj)
+                  : "error object is not a string";
+  /* produce warning "error in %s (%s)" (where, msg) */
+  luaE_warning(L, "error in ", 1);
+  luaE_warning(L, where, 1);
+  luaE_warning(L, " (", 1);
+  luaE_warning(L, msg, 1);
+  luaE_warning(L, ")", 0);
+}
+
diff --git a/test/external/lua-5.4.0/src/lstate.h b/test/external/lua-5.4.0/src/lstate.h
new file mode 100644
index 0000000..2e8bd6c
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lstate.h
@@ -0,0 +1,364 @@
+/*
+** $Id: lstate.h $
+** Global State
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lstate_h
+#define lstate_h
+
+#include "lua.h"
+
+#include "lobject.h"
+#include "ltm.h"
+#include "lzio.h"
+
+
+/*
+** Some notes about garbage-collected objects: All objects in Lua must
+** be kept somehow accessible until being freed, so all objects always
+** belong to one (and only one) of these lists, using field 'next' of
+** the 'CommonHeader' for the link:
+**
+** 'allgc': all objects not marked for finalization;
+** 'finobj': all objects marked for finalization;
+** 'tobefnz': all objects ready to be finalized;
+** 'fixedgc': all objects that are not to be collected (currently
+** only small strings, such as reserved words).
+**
+** For the generational collector, some of these lists have marks for
+** generations. Each mark points to the first element in the list for
+** that particular generation; that generation goes until the next mark.
+**
+** 'allgc' -> 'survival': new objects;
+** 'survival' -> 'old': objects that survived one collection;
+** 'old' -> 'reallyold': objects that became old in last collection;
+** 'reallyold' -> NULL: objects old for more than one cycle.
+**
+** 'finobj' -> 'finobjsur': new objects marked for finalization;
+** 'finobjsur' -> 'finobjold': survived   """";
+** 'finobjold' -> 'finobjrold': just old  """";
+** 'finobjrold' -> NULL: really old       """".
+*/
+
+/*
+** Moreover, there is another set of lists that control gray objects.
+** These lists are linked by fields 'gclist'. (All objects that
+** can become gray have such a field. The field is not the same
+** in all objects, but it always has this name.)  Any gray object
+** must belong to one of these lists, and all objects in these lists
+** must be gray:
+**
+** 'gray': regular gray objects, still waiting to be visited.
+** 'grayagain': objects that must be revisited at the atomic phase.
+**   That includes
+**   - black objects got in a write barrier;
+**   - all kinds of weak tables during propagation phase;
+**   - all threads.
+** 'weak': tables with weak values to be cleared;
+** 'ephemeron': ephemeron tables with white->white entries;
+** 'allweak': tables with weak keys and/or weak values to be cleared.
+*/
+
+
+
+/*
+** About 'nCcalls': each thread in Lua (a lua_State) keeps a count of
+** how many "C calls" it still can do in the C stack, to avoid C-stack
+** overflow.  This count is very rough approximation; it considers only
+** recursive functions inside the interpreter, as non-recursive calls
+** can be considered using a fixed (although unknown) amount of stack
+** space.
+**
+** The count has two parts: the lower part is the count itself; the
+** higher part counts the number of non-yieldable calls in the stack.
+** (They are together so that we can change both with one instruction.)
+**
+** Because calls to external C functions can use an unknown amount
+** of space (e.g., functions using an auxiliary buffer), calls
+** to these functions add more than one to the count (see CSTACKCF).
+**
+** The proper count excludes the number of CallInfo structures allocated
+** by Lua, as a kind of "potential" calls. So, when Lua calls a function
+** (and "consumes" one CallInfo), it needs neither to decrement nor to
+** check 'nCcalls', as its use of C stack is already accounted for.
+*/
+
+/* number of "C stack slots" used by an external C function */
+#define CSTACKCF	10
+
+
+/*
+** The C-stack size is sliced in the following zones:
+** - larger than CSTACKERR: normal stack;
+** - [CSTACKMARK, CSTACKERR]: buffer zone to signal a stack overflow;
+** - [CSTACKCF, CSTACKERRMARK]: error-handling zone;
+** - below CSTACKERRMARK: buffer zone to signal overflow during overflow;
+** (Because the counter can be decremented CSTACKCF at once, we need
+** the so called "buffer zones", with at least that size, to properly
+** detect a change from one zone to the next.)
+*/
+#define CSTACKERR	(8 * CSTACKCF)
+#define CSTACKMARK	(CSTACKERR - (CSTACKCF + 2))
+#define CSTACKERRMARK	(CSTACKCF + 2)
+
+
+/* initial limit for the C-stack of threads */
+#define CSTACKTHREAD	(2 * CSTACKERR)
+
+
+/* true if this thread does not have non-yieldable calls in the stack */
+#define yieldable(L)		(((L)->nCcalls & 0xffff0000) == 0)
+
+/* real number of C calls */
+#define getCcalls(L)	((L)->nCcalls & 0xffff)
+
+
+/* Increment the number of non-yieldable calls */
+#define incnny(L)	((L)->nCcalls += 0x10000)
+
+/* Decrement the number of non-yieldable calls */
+#define decnny(L)	((L)->nCcalls -= 0x10000)
+
+/* Increment the number of non-yieldable calls and decrement nCcalls */
+#define incXCcalls(L)	((L)->nCcalls += 0x10000 - CSTACKCF)
+
+/* Decrement the number of non-yieldable calls and increment nCcalls */
+#define decXCcalls(L)	((L)->nCcalls -= 0x10000 - CSTACKCF)
+
+
+
+
+
+
+struct lua_longjmp;  /* defined in ldo.c */
+
+
+/*
+** Atomic type (relative to signals) to better ensure that 'lua_sethook'
+** is thread safe
+*/
+#if !defined(l_signalT)
+#include <signal.h>
+#define l_signalT	sig_atomic_t
+#endif
+
+
+/* extra stack space to handle TM calls and some other extras */
+#define EXTRA_STACK   5
+
+
+#define BASIC_STACK_SIZE        (2*LUA_MINSTACK)
+
+
+/* kinds of Garbage Collection */
+#define KGC_INC		0	/* incremental gc */
+#define KGC_GEN		1	/* generational gc */
+
+
+typedef struct stringtable {
+  TString **hash;
+  int nuse;  /* number of elements */
+  int size;
+} stringtable;
+
+
+/*
+** Information about a call.
+*/
+typedef struct CallInfo {
+  StkId func;  /* function index in the stack */
+  StkId	top;  /* top for this function */
+  struct CallInfo *previous, *next;  /* dynamic call link */
+  union {
+    struct {  /* only for Lua functions */
+      const Instruction *savedpc;
+      volatile l_signalT trap;
+      int nextraargs;  /* # of extra arguments in vararg functions */
+    } l;
+    struct {  /* only for C functions */
+      lua_KFunction k;  /* continuation in case of yields */
+      ptrdiff_t old_errfunc;
+      lua_KContext ctx;  /* context info. in case of yields */
+    } c;
+  } u;
+  union {
+    int funcidx;  /* called-function index */
+    int nyield;  /* number of values yielded */
+    struct {  /* info about transferred values (for call/return hooks) */
+      unsigned short ftransfer;  /* offset of first value transferred */
+      unsigned short ntransfer;  /* number of values transferred */
+    } transferinfo;
+  } u2;
+  short nresults;  /* expected number of results from this function */
+  unsigned short callstatus;
+} CallInfo;
+
+
+/*
+** Bits in CallInfo status
+*/
+#define CIST_OAH	(1<<0)	/* original value of 'allowhook' */
+#define CIST_C		(1<<1)	/* call is running a C function */
+#define CIST_HOOKED	(1<<2)	/* call is running a debug hook */
+#define CIST_YPCALL	(1<<3)	/* call is a yieldable protected call */
+#define CIST_TAIL	(1<<4)	/* call was tail called */
+#define CIST_HOOKYIELD	(1<<5)	/* last hook called yielded */
+#define CIST_FIN	(1<<6)  /* call is running a finalizer */
+#define CIST_TRAN	(1<<7)	/* 'ci' has transfer information */
+#if defined(LUA_COMPAT_LT_LE)
+#define CIST_LEQ	(1<<8)  /* using __lt for __le */
+#endif
+
+/* active function is a Lua function */
+#define isLua(ci)	(!((ci)->callstatus & CIST_C))
+
+/* call is running Lua code (not a hook) */
+#define isLuacode(ci)	(!((ci)->callstatus & (CIST_C | CIST_HOOKED)))
+
+/* assume that CIST_OAH has offset 0 and that 'v' is strictly 0/1 */
+#define setoah(st,v)	((st) = ((st) & ~CIST_OAH) | (v))
+#define getoah(st)	((st) & CIST_OAH)
+
+
+/*
+** 'global state', shared by all threads of this state
+*/
+typedef struct global_State {
+  lua_Alloc frealloc;  /* function to reallocate memory */
+  void *ud;         /* auxiliary data to 'frealloc' */
+  l_mem totalbytes;  /* number of bytes currently allocated - GCdebt */
+  l_mem GCdebt;  /* bytes allocated not yet compensated by the collector */
+  lu_mem GCestimate;  /* an estimate of the non-garbage memory in use */
+  lu_mem lastatomic;  /* see function 'genstep' in file 'lgc.c' */
+  stringtable strt;  /* hash table for strings */
+  TValue l_registry;
+  TValue nilvalue;  /* a nil value */
+  unsigned int seed;  /* randomized seed for hashes */
+  lu_byte currentwhite;
+  lu_byte gcstate;  /* state of garbage collector */
+  lu_byte gckind;  /* kind of GC running */
+  lu_byte genminormul;  /* control for minor generational collections */
+  lu_byte genmajormul;  /* control for major generational collections */
+  lu_byte gcrunning;  /* true if GC is running */
+  lu_byte gcemergency;  /* true if this is an emergency collection */
+  lu_byte gcpause;  /* size of pause between successive GCs */
+  lu_byte gcstepmul;  /* GC "speed" */
+  lu_byte gcstepsize;  /* (log2 of) GC granularity */
+  GCObject *allgc;  /* list of all collectable objects */
+  GCObject **sweepgc;  /* current position of sweep in list */
+  GCObject *finobj;  /* list of collectable objects with finalizers */
+  GCObject *gray;  /* list of gray objects */
+  GCObject *grayagain;  /* list of objects to be traversed atomically */
+  GCObject *weak;  /* list of tables with weak values */
+  GCObject *ephemeron;  /* list of ephemeron tables (weak keys) */
+  GCObject *allweak;  /* list of all-weak tables */
+  GCObject *tobefnz;  /* list of userdata to be GC */
+  GCObject *fixedgc;  /* list of objects not to be collected */
+  /* fields for generational collector */
+  GCObject *survival;  /* start of objects that survived one GC cycle */
+  GCObject *old;  /* start of old objects */
+  GCObject *reallyold;  /* old objects with more than one cycle */
+  GCObject *finobjsur;  /* list of survival objects with finalizers */
+  GCObject *finobjold;  /* list of old objects with finalizers */
+  GCObject *finobjrold;  /* list of really old objects with finalizers */
+  struct lua_State *twups;  /* list of threads with open upvalues */
+  lua_CFunction panic;  /* to be called in unprotected errors */
+  struct lua_State *mainthread;
+  TString *memerrmsg;  /* message for memory-allocation errors */
+  TString *tmname[TM_N];  /* array with tag-method names */
+  struct Table *mt[LUA_NUMTAGS];  /* metatables for basic types */
+  TString *strcache[STRCACHE_N][STRCACHE_M];  /* cache for strings in API */
+  lua_WarnFunction warnf;  /* warning function */
+  void *ud_warn;         /* auxiliary data to 'warnf' */
+  unsigned int Cstacklimit;  /* current limit for the C stack */
+} global_State;
+
+
+/*
+** 'per thread' state
+*/
+struct lua_State {
+  CommonHeader;
+  lu_byte status;
+  lu_byte allowhook;
+  unsigned short nci;  /* number of items in 'ci' list */
+  StkId top;  /* first free slot in the stack */
+  global_State *l_G;
+  CallInfo *ci;  /* call info for current function */
+  const Instruction *oldpc;  /* last pc traced */
+  StkId stack_last;  /* last free slot in the stack */
+  StkId stack;  /* stack base */
+  UpVal *openupval;  /* list of open upvalues in this stack */
+  GCObject *gclist;
+  struct lua_State *twups;  /* list of threads with open upvalues */
+  struct lua_longjmp *errorJmp;  /* current error recover point */
+  CallInfo base_ci;  /* CallInfo for first level (C calling Lua) */
+  volatile lua_Hook hook;
+  ptrdiff_t errfunc;  /* current error handling function (stack index) */
+  l_uint32 nCcalls;  /* number of allowed nested C calls - 'nci' */
+  int stacksize;
+  int basehookcount;
+  int hookcount;
+  volatile l_signalT hookmask;
+};
+
+
+#define G(L)	(L->l_G)
+
+
+/*
+** Union of all collectable objects (only for conversions)
+*/
+union GCUnion {
+  GCObject gc;  /* common header */
+  struct TString ts;
+  struct Udata u;
+  union Closure cl;
+  struct Table h;
+  struct Proto p;
+  struct lua_State th;  /* thread */
+  struct UpVal upv;
+};
+
+
+#define cast_u(o)	cast(union GCUnion *, (o))
+
+/* macros to convert a GCObject into a specific value */
+#define gco2ts(o)  \
+	check_exp(novariant((o)->tt) == LUA_TSTRING, &((cast_u(o))->ts))
+#define gco2u(o)  check_exp((o)->tt == LUA_VUSERDATA, &((cast_u(o))->u))
+#define gco2lcl(o)  check_exp((o)->tt == LUA_VLCL, &((cast_u(o))->cl.l))
+#define gco2ccl(o)  check_exp((o)->tt == LUA_VCCL, &((cast_u(o))->cl.c))
+#define gco2cl(o)  \
+	check_exp(novariant((o)->tt) == LUA_TFUNCTION, &((cast_u(o))->cl))
+#define gco2t(o)  check_exp((o)->tt == LUA_VTABLE, &((cast_u(o))->h))
+#define gco2p(o)  check_exp((o)->tt == LUA_VPROTO, &((cast_u(o))->p))
+#define gco2th(o)  check_exp((o)->tt == LUA_VTHREAD, &((cast_u(o))->th))
+#define gco2upv(o)	check_exp((o)->tt == LUA_VUPVAL, &((cast_u(o))->upv))
+
+
+/*
+** macro to convert a Lua object into a GCObject
+** (The access to 'tt' tries to ensure that 'v' is actually a Lua object.)
+*/
+#define obj2gco(v)	check_exp((v)->tt >= LUA_TSTRING, &(cast_u(v)->gc))
+
+
+/* actual number of total bytes allocated */
+#define gettotalbytes(g)	cast(lu_mem, (g)->totalbytes + (g)->GCdebt)
+
+LUAI_FUNC void luaE_setdebt (global_State *g, l_mem debt);
+LUAI_FUNC void luaE_freethread (lua_State *L, lua_State *L1);
+LUAI_FUNC CallInfo *luaE_extendCI (lua_State *L);
+LUAI_FUNC void luaE_freeCI (lua_State *L);
+LUAI_FUNC void luaE_shrinkCI (lua_State *L);
+LUAI_FUNC void luaE_enterCcall (lua_State *L);
+LUAI_FUNC void luaE_warning (lua_State *L, const char *msg, int tocont);
+LUAI_FUNC void luaE_warnerror (lua_State *L, const char *where);
+
+
+#define luaE_exitCcall(L)	((L)->nCcalls++)
+
+#endif
+
diff --git a/test/external/lua-5.4.0/src/lstring.c b/test/external/lua-5.4.0/src/lstring.c
new file mode 100644
index 0000000..6f15747
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lstring.c
@@ -0,0 +1,285 @@
+/*
+** $Id: lstring.c $
+** String table (keeps all strings handled by Lua)
+** See Copyright Notice in lua.h
+*/
+
+#define lstring_c
+#define LUA_CORE
+
+#include "lprefix.h"
+
+
+#include <string.h>
+
+#include "lua.h"
+
+#include "ldebug.h"
+#include "ldo.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lstate.h"
+#include "lstring.h"
+
+
+/*
+** Lua will use at most ~(2^LUAI_HASHLIMIT) bytes from a long string to
+** compute its hash
+*/
+#if !defined(LUAI_HASHLIMIT)
+#define LUAI_HASHLIMIT		5
+#endif
+
+
+
+/*
+** Maximum size for string table.
+*/
+#define MAXSTRTB	cast_int(luaM_limitN(MAX_INT, TString*))
+
+
+/*
+** equality for long strings
+*/
+int luaS_eqlngstr (TString *a, TString *b) {
+  size_t len = a->u.lnglen;
+  lua_assert(a->tt == LUA_VLNGSTR && b->tt == LUA_VLNGSTR);
+  return (a == b) ||  /* same instance or... */
+    ((len == b->u.lnglen) &&  /* equal length and ... */
+     (memcmp(getstr(a), getstr(b), len) == 0));  /* equal contents */
+}
+
+
+unsigned int luaS_hash (const char *str, size_t l, unsigned int seed,
+                        size_t step) {
+  unsigned int h = seed ^ cast_uint(l);
+  for (; l >= step; l -= step)
+    h ^= ((h<<5) + (h>>2) + cast_byte(str[l - 1]));
+  return h;
+}
+
+
+unsigned int luaS_hashlongstr (TString *ts) {
+  lua_assert(ts->tt == LUA_VLNGSTR);
+  if (ts->extra == 0) {  /* no hash? */
+    size_t len = ts->u.lnglen;
+    size_t step = (len >> LUAI_HASHLIMIT) + 1;
+    ts->hash = luaS_hash(getstr(ts), len, ts->hash, step);
+    ts->extra = 1;  /* now it has its hash */
+  }
+  return ts->hash;
+}
+
+
+static void tablerehash (TString **vect, int osize, int nsize) {
+  int i;
+  for (i = osize; i < nsize; i++)  /* clear new elements */
+    vect[i] = NULL;
+  for (i = 0; i < osize; i++) {  /* rehash old part of the array */
+    TString *p = vect[i];
+    vect[i] = NULL;
+    while (p) {  /* for each string in the list */
+      TString *hnext = p->u.hnext;  /* save next */
+      unsigned int h = lmod(p->hash, nsize);  /* new position */
+      p->u.hnext = vect[h];  /* chain it into array */
+      vect[h] = p;
+      p = hnext;
+    }
+  }
+}
+
+
+/*
+** Resize the string table. If allocation fails, keep the current size.
+** (This can degrade performance, but any non-zero size should work
+** correctly.)
+*/
+void luaS_resize (lua_State *L, int nsize) {
+  stringtable *tb = &G(L)->strt;
+  int osize = tb->size;
+  TString **newvect;
+  if (nsize < osize)  /* shrinking table? */
+    tablerehash(tb->hash, osize, nsize);  /* depopulate shrinking part */
+  newvect = luaM_reallocvector(L, tb->hash, osize, nsize, TString*);
+  if (unlikely(newvect == NULL)) {  /* reallocation failed? */
+    if (nsize < osize)  /* was it shrinking table? */
+      tablerehash(tb->hash, nsize, osize);  /* restore to original size */
+    /* leave table as it was */
+  }
+  else {  /* allocation succeeded */
+    tb->hash = newvect;
+    tb->size = nsize;
+    if (nsize > osize)
+      tablerehash(newvect, osize, nsize);  /* rehash for new size */
+  }
+}
+
+
+/*
+** Clear API string cache. (Entries cannot be empty, so fill them with
+** a non-collectable string.)
+*/
+void luaS_clearcache (global_State *g) {
+  int i, j;
+  for (i = 0; i < STRCACHE_N; i++)
+    for (j = 0; j < STRCACHE_M; j++) {
+      if (iswhite(g->strcache[i][j]))  /* will entry be collected? */
+        g->strcache[i][j] = g->memerrmsg;  /* replace it with something fixed */
+    }
+}
+
+
+/*
+** Initialize the string table and the string cache
+*/
+void luaS_init (lua_State *L) {
+  global_State *g = G(L);
+  int i, j;
+  stringtable *tb = &G(L)->strt;
+  tb->hash = luaM_newvector(L, MINSTRTABSIZE, TString*);
+  tablerehash(tb->hash, 0, MINSTRTABSIZE);  /* clear array */
+  tb->size = MINSTRTABSIZE;
+  /* pre-create memory-error message */
+  g->memerrmsg = luaS_newliteral(L, MEMERRMSG);
+  luaC_fix(L, obj2gco(g->memerrmsg));  /* it should never be collected */
+  for (i = 0; i < STRCACHE_N; i++)  /* fill cache with valid strings */
+    for (j = 0; j < STRCACHE_M; j++)
+      g->strcache[i][j] = g->memerrmsg;
+}
+
+
+
+/*
+** creates a new string object
+*/
+static TString *createstrobj (lua_State *L, size_t l, int tag, unsigned int h) {
+  TString *ts;
+  GCObject *o;
+  size_t totalsize;  /* total size of TString object */
+  totalsize = sizelstring(l);
+  o = luaC_newobj(L, tag, totalsize);
+  ts = gco2ts(o);
+  ts->hash = h;
+  ts->extra = 0;
+  getstr(ts)[l] = '\0';  /* ending 0 */
+  return ts;
+}
+
+
+TString *luaS_createlngstrobj (lua_State *L, size_t l) {
+  TString *ts = createstrobj(L, l, LUA_VLNGSTR, G(L)->seed);
+  ts->u.lnglen = l;
+  return ts;
+}
+
+
+void luaS_remove (lua_State *L, TString *ts) {
+  stringtable *tb = &G(L)->strt;
+  TString **p = &tb->hash[lmod(ts->hash, tb->size)];
+  while (*p != ts)  /* find previous element */
+    p = &(*p)->u.hnext;
+  *p = (*p)->u.hnext;  /* remove element from its list */
+  tb->nuse--;
+}
+
+
+static void growstrtab (lua_State *L, stringtable *tb) {
+  if (unlikely(tb->nuse == MAX_INT)) {  /* too many strings? */
+    luaC_fullgc(L, 1);  /* try to free some... */
+    if (tb->nuse == MAX_INT)  /* still too many? */
+      luaM_error(L);  /* cannot even create a message... */
+  }
+  if (tb->size <= MAXSTRTB / 2)  /* can grow string table? */
+    luaS_resize(L, tb->size * 2);
+}
+
+
+/*
+** Checks whether short string exists and reuses it or creates a new one.
+*/
+static TString *internshrstr (lua_State *L, const char *str, size_t l) {
+  TString *ts;
+  global_State *g = G(L);
+  stringtable *tb = &g->strt;
+  unsigned int h = luaS_hash(str, l, g->seed, 1);
+  TString **list = &tb->hash[lmod(h, tb->size)];
+  lua_assert(str != NULL);  /* otherwise 'memcmp'/'memcpy' are undefined */
+  for (ts = *list; ts != NULL; ts = ts->u.hnext) {
+    if (l == ts->shrlen && (memcmp(str, getstr(ts), l * sizeof(char)) == 0)) {
+      /* found! */
+      if (isdead(g, ts))  /* dead (but not collected yet)? */
+        changewhite(ts);  /* resurrect it */
+      return ts;
+    }
+  }
+  /* else must create a new string */
+  if (tb->nuse >= tb->size) {  /* need to grow string table? */
+    growstrtab(L, tb);
+    list = &tb->hash[lmod(h, tb->size)];  /* rehash with new size */
+  }
+  ts = createstrobj(L, l, LUA_VSHRSTR, h);
+  memcpy(getstr(ts), str, l * sizeof(char));
+  ts->shrlen = cast_byte(l);
+  ts->u.hnext = *list;
+  *list = ts;
+  tb->nuse++;
+  return ts;
+}
+
+
+/*
+** new string (with explicit length)
+*/
+TString *luaS_newlstr (lua_State *L, const char *str, size_t l) {
+  if (l <= LUAI_MAXSHORTLEN)  /* short string? */
+    return internshrstr(L, str, l);
+  else {
+    TString *ts;
+    if (unlikely(l >= (MAX_SIZE - sizeof(TString))/sizeof(char)))
+      luaM_toobig(L);
+    ts = luaS_createlngstrobj(L, l);
+    memcpy(getstr(ts), str, l * sizeof(char));
+    return ts;
+  }
+}
+
+
+/*
+** Create or reuse a zero-terminated string, first checking in the
+** cache (using the string address as a key). The cache can contain
+** only zero-terminated strings, so it is safe to use 'strcmp' to
+** check hits.
+*/
+TString *luaS_new (lua_State *L, const char *str) {
+  unsigned int i = point2uint(str) % STRCACHE_N;  /* hash */
+  int j;
+  TString **p = G(L)->strcache[i];
+  for (j = 0; j < STRCACHE_M; j++) {
+    if (strcmp(str, getstr(p[j])) == 0)  /* hit? */
+      return p[j];  /* that is it */
+  }
+  /* normal route */
+  for (j = STRCACHE_M - 1; j > 0; j--)
+    p[j] = p[j - 1];  /* move out last element */
+  /* new element is first in the list */
+  p[0] = luaS_newlstr(L, str, strlen(str));
+  return p[0];
+}
+
+
+Udata *luaS_newudata (lua_State *L, size_t s, int nuvalue) {
+  Udata *u;
+  int i;
+  GCObject *o;
+  if (unlikely(s > MAX_SIZE - udatamemoffset(nuvalue)))
+    luaM_toobig(L);
+  o = luaC_newobj(L, LUA_VUSERDATA, sizeudata(nuvalue, s));
+  u = gco2u(o);
+  u->len = s;
+  u->nuvalue = nuvalue;
+  u->metatable = NULL;
+  for (i = 0; i < nuvalue; i++)
+    setnilvalue(&u->uv[i].uv);
+  return u;
+}
+
diff --git a/test/external/lua-5.4.0/src/lstring.h b/test/external/lua-5.4.0/src/lstring.h
new file mode 100644
index 0000000..a413a9d
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lstring.h
@@ -0,0 +1,58 @@
+/*
+** $Id: lstring.h $
+** String table (keep all strings handled by Lua)
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lstring_h
+#define lstring_h
+
+#include "lgc.h"
+#include "lobject.h"
+#include "lstate.h"
+
+
+/*
+** Memory-allocation error message must be preallocated (it cannot
+** be created after memory is exhausted)
+*/
+#define MEMERRMSG       "not enough memory"
+
+
+/*
+** Size of a TString: Size of the header plus space for the string
+** itself (including final '\0').
+*/
+#define sizelstring(l)  (offsetof(TString, contents) + ((l) + 1) * sizeof(char))
+
+#define luaS_newliteral(L, s)	(luaS_newlstr(L, "" s, \
+                                 (sizeof(s)/sizeof(char))-1))
+
+
+/*
+** test whether a string is a reserved word
+*/
+#define isreserved(s)	((s)->tt == LUA_VSHRSTR && (s)->extra > 0)
+
+
+/*
+** equality for short strings, which are always internalized
+*/
+#define eqshrstr(a,b)	check_exp((a)->tt == LUA_VSHRSTR, (a) == (b))
+
+
+LUAI_FUNC unsigned int luaS_hash (const char *str, size_t l,
+                                  unsigned int seed, size_t step);
+LUAI_FUNC unsigned int luaS_hashlongstr (TString *ts);
+LUAI_FUNC int luaS_eqlngstr (TString *a, TString *b);
+LUAI_FUNC void luaS_resize (lua_State *L, int newsize);
+LUAI_FUNC void luaS_clearcache (global_State *g);
+LUAI_FUNC void luaS_init (lua_State *L);
+LUAI_FUNC void luaS_remove (lua_State *L, TString *ts);
+LUAI_FUNC Udata *luaS_newudata (lua_State *L, size_t s, int nuvalue);
+LUAI_FUNC TString *luaS_newlstr (lua_State *L, const char *str, size_t l);
+LUAI_FUNC TString *luaS_new (lua_State *L, const char *str);
+LUAI_FUNC TString *luaS_createlngstrobj (lua_State *L, size_t l);
+
+
+#endif
diff --git a/test/external/lua-5.4.0/src/lstrlib.c b/test/external/lua-5.4.0/src/lstrlib.c
new file mode 100644
index 0000000..2ba8bde
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lstrlib.c
@@ -0,0 +1,1805 @@
+/*
+** $Id: lstrlib.c $
+** Standard library for string operations and pattern-matching
+** See Copyright Notice in lua.h
+*/
+
+#define lstrlib_c
+#define LUA_LIB
+
+#include "lprefix.h"
+
+
+#include <ctype.h>
+#include <float.h>
+#include <limits.h>
+#include <locale.h>
+#include <math.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+/*
+** maximum number of captures that a pattern can do during
+** pattern-matching. This limit is arbitrary, but must fit in
+** an unsigned char.
+*/
+#if !defined(LUA_MAXCAPTURES)
+#define LUA_MAXCAPTURES		32
+#endif
+
+
+/* macro to 'unsign' a character */
+#define uchar(c)	((unsigned char)(c))
+
+
+/*
+** Some sizes are better limited to fit in 'int', but must also fit in
+** 'size_t'. (We assume that 'lua_Integer' cannot be smaller than 'int'.)
+*/
+#define MAX_SIZET	((size_t)(~(size_t)0))
+
+#define MAXSIZE  \
+	(sizeof(size_t) < sizeof(int) ? MAX_SIZET : (size_t)(INT_MAX))
+
+
+
+
+static int str_len (lua_State *L) {
+  size_t l;
+  luaL_checklstring(L, 1, &l);
+  lua_pushinteger(L, (lua_Integer)l);
+  return 1;
+}
+
+
+/*
+** translate a relative initial string position
+** (negative means back from end): clip result to [1, inf).
+** The length of any string in Lua must fit in a lua_Integer,
+** so there are no overflows in the casts.
+** The inverted comparison avoids a possible overflow
+** computing '-pos'.
+*/
+static size_t posrelatI (lua_Integer pos, size_t len) {
+  if (pos > 0)
+    return (size_t)pos;
+  else if (pos == 0)
+    return 1;
+  else if (pos < -(lua_Integer)len)  /* inverted comparison */
+    return 1;  /* clip to 1 */
+  else return len + (size_t)pos + 1;
+}
+
+
+/*
+** Gets an optional ending string position from argument 'arg',
+** with default value 'def'.
+** Negative means back from end: clip result to [0, len]
+*/
+static size_t getendpos (lua_State *L, int arg, lua_Integer def,
+                         size_t len) {
+  lua_Integer pos = luaL_optinteger(L, arg, def);
+  if (pos > (lua_Integer)len)
+    return len;
+  else if (pos >= 0)
+    return (size_t)pos;
+  else if (pos < -(lua_Integer)len)
+    return 0;
+  else return len + (size_t)pos + 1;
+}
+
+
+static int str_sub (lua_State *L) {
+  size_t l;
+  const char *s = luaL_checklstring(L, 1, &l);
+  size_t start = posrelatI(luaL_checkinteger(L, 2), l);
+  size_t end = getendpos(L, 3, -1, l);
+  if (start <= end)
+    lua_pushlstring(L, s + start - 1, (end - start) + 1);
+  else lua_pushliteral(L, "");
+  return 1;
+}
+
+
+static int str_reverse (lua_State *L) {
+  size_t l, i;
+  luaL_Buffer b;
+  const char *s = luaL_checklstring(L, 1, &l);
+  char *p = luaL_buffinitsize(L, &b, l);
+  for (i = 0; i < l; i++)
+    p[i] = s[l - i - 1];
+  luaL_pushresultsize(&b, l);
+  return 1;
+}
+
+
+static int str_lower (lua_State *L) {
+  size_t l;
+  size_t i;
+  luaL_Buffer b;
+  const char *s = luaL_checklstring(L, 1, &l);
+  char *p = luaL_buffinitsize(L, &b, l);
+  for (i=0; i<l; i++)
+    p[i] = tolower(uchar(s[i]));
+  luaL_pushresultsize(&b, l);
+  return 1;
+}
+
+
+static int str_upper (lua_State *L) {
+  size_t l;
+  size_t i;
+  luaL_Buffer b;
+  const char *s = luaL_checklstring(L, 1, &l);
+  char *p = luaL_buffinitsize(L, &b, l);
+  for (i=0; i<l; i++)
+    p[i] = toupper(uchar(s[i]));
+  luaL_pushresultsize(&b, l);
+  return 1;
+}
+
+
+static int str_rep (lua_State *L) {
+  size_t l, lsep;
+  const char *s = luaL_checklstring(L, 1, &l);
+  lua_Integer n = luaL_checkinteger(L, 2);
+  const char *sep = luaL_optlstring(L, 3, "", &lsep);
+  if (n <= 0) lua_pushliteral(L, "");
+  else if (l + lsep < l || l + lsep > MAXSIZE / n)  /* may overflow? */
+    return luaL_error(L, "resulting string too large");
+  else {
+    size_t totallen = (size_t)n * l + (size_t)(n - 1) * lsep;
+    luaL_Buffer b;
+    char *p = luaL_buffinitsize(L, &b, totallen);
+    while (n-- > 1) {  /* first n-1 copies (followed by separator) */
+      memcpy(p, s, l * sizeof(char)); p += l;
+      if (lsep > 0) {  /* empty 'memcpy' is not that cheap */
+        memcpy(p, sep, lsep * sizeof(char));
+        p += lsep;
+      }
+    }
+    memcpy(p, s, l * sizeof(char));  /* last copy (not followed by separator) */
+    luaL_pushresultsize(&b, totallen);
+  }
+  return 1;
+}
+
+
+static int str_byte (lua_State *L) {
+  size_t l;
+  const char *s = luaL_checklstring(L, 1, &l);
+  lua_Integer pi = luaL_optinteger(L, 2, 1);
+  size_t posi = posrelatI(pi, l);
+  size_t pose = getendpos(L, 3, pi, l);
+  int n, i;
+  if (posi > pose) return 0;  /* empty interval; return no values */
+  if (pose - posi >= (size_t)INT_MAX)  /* arithmetic overflow? */
+    return luaL_error(L, "string slice too long");
+  n = (int)(pose -  posi) + 1;
+  luaL_checkstack(L, n, "string slice too long");
+  for (i=0; i<n; i++)
+    lua_pushinteger(L, uchar(s[posi+i-1]));
+  return n;
+}
+
+
+static int str_char (lua_State *L) {
+  int n = lua_gettop(L);  /* number of arguments */
+  int i;
+  luaL_Buffer b;
+  char *p = luaL_buffinitsize(L, &b, n);
+  for (i=1; i<=n; i++) {
+    lua_Unsigned c = (lua_Unsigned)luaL_checkinteger(L, i);
+    luaL_argcheck(L, c <= (lua_Unsigned)UCHAR_MAX, i, "value out of range");
+    p[i - 1] = uchar(c);
+  }
+  luaL_pushresultsize(&b, n);
+  return 1;
+}
+
+
+/*
+** Buffer to store the result of 'string.dump'. It must be initialized
+** after the call to 'lua_dump', to ensure that the function is on the
+** top of the stack when 'lua_dump' is called. ('luaL_buffinit' might
+** push stuff.)
+*/
+struct str_Writer {
+  int init;  /* true iff buffer has been initialized */
+  luaL_Buffer B;
+};
+
+
+static int writer (lua_State *L, const void *b, size_t size, void *ud) {
+  struct str_Writer *state = (struct str_Writer *)ud;
+  if (!state->init) {
+    state->init = 1;
+    luaL_buffinit(L, &state->B);
+  }
+  luaL_addlstring(&state->B, (const char *)b, size);
+  return 0;
+}
+
+
+static int str_dump (lua_State *L) {
+  struct str_Writer state;
+  int strip = lua_toboolean(L, 2);
+  luaL_checktype(L, 1, LUA_TFUNCTION);
+  lua_settop(L, 1);  /* ensure function is on the top of the stack */
+  state.init = 0;
+  if (lua_dump(L, writer, &state, strip) != 0)
+    return luaL_error(L, "unable to dump given function");
+  luaL_pushresult(&state.B);
+  return 1;
+}
+
+
+
+/*
+** {======================================================
+** METAMETHODS
+** =======================================================
+*/
+
+#if defined(LUA_NOCVTS2N)	/* { */
+
+/* no coercion from strings to numbers */
+
+static const luaL_Reg stringmetamethods[] = {
+  {"__index", NULL},  /* placeholder */
+  {NULL, NULL}
+};
+
+#else		/* }{ */
+
+static int tonum (lua_State *L, int arg) {
+  if (lua_type(L, arg) == LUA_TNUMBER) {  /* already a number? */
+    lua_pushvalue(L, arg);
+    return 1;
+  }
+  else {  /* check whether it is a numerical string */
+    size_t len;
+    const char *s = lua_tolstring(L, arg, &len);
+    return (s != NULL && lua_stringtonumber(L, s) == len + 1);
+  }
+}
+
+
+static void trymt (lua_State *L, const char *mtname) {
+  lua_settop(L, 2);  /* back to the original arguments */
+  if (lua_type(L, 2) == LUA_TSTRING || !luaL_getmetafield(L, 2, mtname))
+    luaL_error(L, "attempt to %s a '%s' with a '%s'", mtname + 2,
+                  luaL_typename(L, -2), luaL_typename(L, -1));
+  lua_insert(L, -3);  /* put metamethod before arguments */
+  lua_call(L, 2, 1);  /* call metamethod */
+}
+
+
+static int arith (lua_State *L, int op, const char *mtname) {
+  if (tonum(L, 1) && tonum(L, 2))
+    lua_arith(L, op);  /* result will be on the top */
+  else
+    trymt(L, mtname);
+  return 1;
+}
+
+
+static int arith_add (lua_State *L) {
+  return arith(L, LUA_OPADD, "__add");
+}
+
+static int arith_sub (lua_State *L) {
+  return arith(L, LUA_OPSUB, "__sub");
+}
+
+static int arith_mul (lua_State *L) {
+  return arith(L, LUA_OPMUL, "__mul");
+}
+
+static int arith_mod (lua_State *L) {
+  return arith(L, LUA_OPMOD, "__mod");
+}
+
+static int arith_pow (lua_State *L) {
+  return arith(L, LUA_OPPOW, "__pow");
+}
+
+static int arith_div (lua_State *L) {
+  return arith(L, LUA_OPDIV, "__div");
+}
+
+static int arith_idiv (lua_State *L) {
+  return arith(L, LUA_OPIDIV, "__idiv");
+}
+
+static int arith_unm (lua_State *L) {
+  return arith(L, LUA_OPUNM, "__unm");
+}
+
+
+static const luaL_Reg stringmetamethods[] = {
+  {"__add", arith_add},
+  {"__sub", arith_sub},
+  {"__mul", arith_mul},
+  {"__mod", arith_mod},
+  {"__pow", arith_pow},
+  {"__div", arith_div},
+  {"__idiv", arith_idiv},
+  {"__unm", arith_unm},
+  {"__index", NULL},  /* placeholder */
+  {NULL, NULL}
+};
+
+#endif		/* } */
+
+/* }====================================================== */
+
+/*
+** {======================================================
+** PATTERN MATCHING
+** =======================================================
+*/
+
+
+#define CAP_UNFINISHED	(-1)
+#define CAP_POSITION	(-2)
+
+
+typedef struct MatchState {
+  const char *src_init;  /* init of source string */
+  const char *src_end;  /* end ('\0') of source string */
+  const char *p_end;  /* end ('\0') of pattern */
+  lua_State *L;
+  int matchdepth;  /* control for recursive depth (to avoid C stack overflow) */
+  unsigned char level;  /* total number of captures (finished or unfinished) */
+  struct {
+    const char *init;
+    ptrdiff_t len;
+  } capture[LUA_MAXCAPTURES];
+} MatchState;
+
+
+/* recursive function */
+static const char *match (MatchState *ms, const char *s, const char *p);
+
+
+/* maximum recursion depth for 'match' */
+#if !defined(MAXCCALLS)
+#define MAXCCALLS	200
+#endif
+
+
+#define L_ESC		'%'
+#define SPECIALS	"^$*+?.([%-"
+
+
+static int check_capture (MatchState *ms, int l) {
+  l -= '1';
+  if (l < 0 || l >= ms->level || ms->capture[l].len == CAP_UNFINISHED)
+    return luaL_error(ms->L, "invalid capture index %%%d", l + 1);
+  return l;
+}
+
+
+static int capture_to_close (MatchState *ms) {
+  int level = ms->level;
+  for (level--; level>=0; level--)
+    if (ms->capture[level].len == CAP_UNFINISHED) return level;
+  return luaL_error(ms->L, "invalid pattern capture");
+}
+
+
+static const char *classend (MatchState *ms, const char *p) {
+  switch (*p++) {
+    case L_ESC: {
+      if (p == ms->p_end)
+        luaL_error(ms->L, "malformed pattern (ends with '%%')");
+      return p+1;
+    }
+    case '[': {
+      if (*p == '^') p++;
+      do {  /* look for a ']' */
+        if (p == ms->p_end)
+          luaL_error(ms->L, "malformed pattern (missing ']')");
+        if (*(p++) == L_ESC && p < ms->p_end)
+          p++;  /* skip escapes (e.g. '%]') */
+      } while (*p != ']');
+      return p+1;
+    }
+    default: {
+      return p;
+    }
+  }
+}
+
+
+static int match_class (int c, int cl) {
+  int res;
+  switch (tolower(cl)) {
+    case 'a' : res = isalpha(c); break;
+    case 'c' : res = iscntrl(c); break;
+    case 'd' : res = isdigit(c); break;
+    case 'g' : res = isgraph(c); break;
+    case 'l' : res = islower(c); break;
+    case 'p' : res = ispunct(c); break;
+    case 's' : res = isspace(c); break;
+    case 'u' : res = isupper(c); break;
+    case 'w' : res = isalnum(c); break;
+    case 'x' : res = isxdigit(c); break;
+    case 'z' : res = (c == 0); break;  /* deprecated option */
+    default: return (cl == c);
+  }
+  return (islower(cl) ? res : !res);
+}
+
+
+static int matchbracketclass (int c, const char *p, const char *ec) {
+  int sig = 1;
+  if (*(p+1) == '^') {
+    sig = 0;
+    p++;  /* skip the '^' */
+  }
+  while (++p < ec) {
+    if (*p == L_ESC) {
+      p++;
+      if (match_class(c, uchar(*p)))
+        return sig;
+    }
+    else if ((*(p+1) == '-') && (p+2 < ec)) {
+      p+=2;
+      if (uchar(*(p-2)) <= c && c <= uchar(*p))
+        return sig;
+    }
+    else if (uchar(*p) == c) return sig;
+  }
+  return !sig;
+}
+
+
+static int singlematch (MatchState *ms, const char *s, const char *p,
+                        const char *ep) {
+  if (s >= ms->src_end)
+    return 0;
+  else {
+    int c = uchar(*s);
+    switch (*p) {
+      case '.': return 1;  /* matches any char */
+      case L_ESC: return match_class(c, uchar(*(p+1)));
+      case '[': return matchbracketclass(c, p, ep-1);
+      default:  return (uchar(*p) == c);
+    }
+  }
+}
+
+
+static const char *matchbalance (MatchState *ms, const char *s,
+                                   const char *p) {
+  if (p >= ms->p_end - 1)
+    luaL_error(ms->L, "malformed pattern (missing arguments to '%%b')");
+  if (*s != *p) return NULL;
+  else {
+    int b = *p;
+    int e = *(p+1);
+    int cont = 1;
+    while (++s < ms->src_end) {
+      if (*s == e) {
+        if (--cont == 0) return s+1;
+      }
+      else if (*s == b) cont++;
+    }
+  }
+  return NULL;  /* string ends out of balance */
+}
+
+
+static const char *max_expand (MatchState *ms, const char *s,
+                                 const char *p, const char *ep) {
+  ptrdiff_t i = 0;  /* counts maximum expand for item */
+  while (singlematch(ms, s + i, p, ep))
+    i++;
+  /* keeps trying to match with the maximum repetitions */
+  while (i>=0) {
+    const char *res = match(ms, (s+i), ep+1);
+    if (res) return res;
+    i--;  /* else didn't match; reduce 1 repetition to try again */
+  }
+  return NULL;
+}
+
+
+static const char *min_expand (MatchState *ms, const char *s,
+                                 const char *p, const char *ep) {
+  for (;;) {
+    const char *res = match(ms, s, ep+1);
+    if (res != NULL)
+      return res;
+    else if (singlematch(ms, s, p, ep))
+      s++;  /* try with one more repetition */
+    else return NULL;
+  }
+}
+
+
+static const char *start_capture (MatchState *ms, const char *s,
+                                    const char *p, int what) {
+  const char *res;
+  int level = ms->level;
+  if (level >= LUA_MAXCAPTURES) luaL_error(ms->L, "too many captures");
+  ms->capture[level].init = s;
+  ms->capture[level].len = what;
+  ms->level = level+1;
+  if ((res=match(ms, s, p)) == NULL)  /* match failed? */
+    ms->level--;  /* undo capture */
+  return res;
+}
+
+
+static const char *end_capture (MatchState *ms, const char *s,
+                                  const char *p) {
+  int l = capture_to_close(ms);
+  const char *res;
+  ms->capture[l].len = s - ms->capture[l].init;  /* close capture */
+  if ((res = match(ms, s, p)) == NULL)  /* match failed? */
+    ms->capture[l].len = CAP_UNFINISHED;  /* undo capture */
+  return res;
+}
+
+
+static const char *match_capture (MatchState *ms, const char *s, int l) {
+  size_t len;
+  l = check_capture(ms, l);
+  len = ms->capture[l].len;
+  if ((size_t)(ms->src_end-s) >= len &&
+      memcmp(ms->capture[l].init, s, len) == 0)
+    return s+len;
+  else return NULL;
+}
+
+
+static const char *match (MatchState *ms, const char *s, const char *p) {
+  if (ms->matchdepth-- == 0)
+    luaL_error(ms->L, "pattern too complex");
+  init: /* using goto's to optimize tail recursion */
+  if (p != ms->p_end) {  /* end of pattern? */
+    switch (*p) {
+      case '(': {  /* start capture */
+        if (*(p + 1) == ')')  /* position capture? */
+          s = start_capture(ms, s, p + 2, CAP_POSITION);
+        else
+          s = start_capture(ms, s, p + 1, CAP_UNFINISHED);
+        break;
+      }
+      case ')': {  /* end capture */
+        s = end_capture(ms, s, p + 1);
+        break;
+      }
+      case '$': {
+        if ((p + 1) != ms->p_end)  /* is the '$' the last char in pattern? */
+          goto dflt;  /* no; go to default */
+        s = (s == ms->src_end) ? s : NULL;  /* check end of string */
+        break;
+      }
+      case L_ESC: {  /* escaped sequences not in the format class[*+?-]? */
+        switch (*(p + 1)) {
+          case 'b': {  /* balanced string? */
+            s = matchbalance(ms, s, p + 2);
+            if (s != NULL) {
+              p += 4; goto init;  /* return match(ms, s, p + 4); */
+            }  /* else fail (s == NULL) */
+            break;
+          }
+          case 'f': {  /* frontier? */
+            const char *ep; char previous;
+            p += 2;
+            if (*p != '[')
+              luaL_error(ms->L, "missing '[' after '%%f' in pattern");
+            ep = classend(ms, p);  /* points to what is next */
+            previous = (s == ms->src_init) ? '\0' : *(s - 1);
+            if (!matchbracketclass(uchar(previous), p, ep - 1) &&
+               matchbracketclass(uchar(*s), p, ep - 1)) {
+              p = ep; goto init;  /* return match(ms, s, ep); */
+            }
+            s = NULL;  /* match failed */
+            break;
+          }
+          case '0': case '1': case '2': case '3':
+          case '4': case '5': case '6': case '7':
+          case '8': case '9': {  /* capture results (%0-%9)? */
+            s = match_capture(ms, s, uchar(*(p + 1)));
+            if (s != NULL) {
+              p += 2; goto init;  /* return match(ms, s, p + 2) */
+            }
+            break;
+          }
+          default: goto dflt;
+        }
+        break;
+      }
+      default: dflt: {  /* pattern class plus optional suffix */
+        const char *ep = classend(ms, p);  /* points to optional suffix */
+        /* does not match at least once? */
+        if (!singlematch(ms, s, p, ep)) {
+          if (*ep == '*' || *ep == '?' || *ep == '-') {  /* accept empty? */
+            p = ep + 1; goto init;  /* return match(ms, s, ep + 1); */
+          }
+          else  /* '+' or no suffix */
+            s = NULL;  /* fail */
+        }
+        else {  /* matched once */
+          switch (*ep) {  /* handle optional suffix */
+            case '?': {  /* optional */
+              const char *res;
+              if ((res = match(ms, s + 1, ep + 1)) != NULL)
+                s = res;
+              else {
+                p = ep + 1; goto init;  /* else return match(ms, s, ep + 1); */
+              }
+              break;
+            }
+            case '+':  /* 1 or more repetitions */
+              s++;  /* 1 match already done */
+              /* FALLTHROUGH */
+            case '*':  /* 0 or more repetitions */
+              s = max_expand(ms, s, p, ep);
+              break;
+            case '-':  /* 0 or more repetitions (minimum) */
+              s = min_expand(ms, s, p, ep);
+              break;
+            default:  /* no suffix */
+              s++; p = ep; goto init;  /* return match(ms, s + 1, ep); */
+          }
+        }
+        break;
+      }
+    }
+  }
+  ms->matchdepth++;
+  return s;
+}
+
+
+
+static const char *lmemfind (const char *s1, size_t l1,
+                               const char *s2, size_t l2) {
+  if (l2 == 0) return s1;  /* empty strings are everywhere */
+  else if (l2 > l1) return NULL;  /* avoids a negative 'l1' */
+  else {
+    const char *init;  /* to search for a '*s2' inside 's1' */
+    l2--;  /* 1st char will be checked by 'memchr' */
+    l1 = l1-l2;  /* 's2' cannot be found after that */
+    while (l1 > 0 && (init = (const char *)memchr(s1, *s2, l1)) != NULL) {
+      init++;   /* 1st char is already checked */
+      if (memcmp(init, s2+1, l2) == 0)
+        return init-1;
+      else {  /* correct 'l1' and 's1' to try again */
+        l1 -= init-s1;
+        s1 = init;
+      }
+    }
+    return NULL;  /* not found */
+  }
+}
+
+
+/*
+** get information about the i-th capture. If there are no captures
+** and 'i==0', return information about the whole match, which
+** is the range 's'..'e'. If the capture is a string, return
+** its length and put its address in '*cap'. If it is an integer
+** (a position), push it on the stack and return CAP_POSITION.
+*/
+static size_t get_onecapture (MatchState *ms, int i, const char *s,
+                              const char *e, const char **cap) {
+  if (i >= ms->level) {
+    if (i != 0)
+      luaL_error(ms->L, "invalid capture index %%%d", i + 1);
+    *cap = s;
+    return e - s;
+  }
+  else {
+    ptrdiff_t capl = ms->capture[i].len;
+    *cap = ms->capture[i].init;
+    if (capl == CAP_UNFINISHED)
+      luaL_error(ms->L, "unfinished capture");
+    else if (capl == CAP_POSITION)
+      lua_pushinteger(ms->L, (ms->capture[i].init - ms->src_init) + 1);
+    return capl;
+  }
+}
+
+
+/*
+** Push the i-th capture on the stack.
+*/
+static void push_onecapture (MatchState *ms, int i, const char *s,
+                                                    const char *e) {
+  const char *cap;
+  ptrdiff_t l = get_onecapture(ms, i, s, e, &cap);
+  if (l != CAP_POSITION)
+    lua_pushlstring(ms->L, cap, l);
+  /* else position was already pushed */
+}
+
+
+static int push_captures (MatchState *ms, const char *s, const char *e) {
+  int i;
+  int nlevels = (ms->level == 0 && s) ? 1 : ms->level;
+  luaL_checkstack(ms->L, nlevels, "too many captures");
+  for (i = 0; i < nlevels; i++)
+    push_onecapture(ms, i, s, e);
+  return nlevels;  /* number of strings pushed */
+}
+
+
+/* check whether pattern has no special characters */
+static int nospecials (const char *p, size_t l) {
+  size_t upto = 0;
+  do {
+    if (strpbrk(p + upto, SPECIALS))
+      return 0;  /* pattern has a special character */
+    upto += strlen(p + upto) + 1;  /* may have more after \0 */
+  } while (upto <= l);
+  return 1;  /* no special chars found */
+}
+
+
+static void prepstate (MatchState *ms, lua_State *L,
+                       const char *s, size_t ls, const char *p, size_t lp) {
+  ms->L = L;
+  ms->matchdepth = MAXCCALLS;
+  ms->src_init = s;
+  ms->src_end = s + ls;
+  ms->p_end = p + lp;
+}
+
+
+static void reprepstate (MatchState *ms) {
+  ms->level = 0;
+  lua_assert(ms->matchdepth == MAXCCALLS);
+}
+
+
+static int str_find_aux (lua_State *L, int find) {
+  size_t ls, lp;
+  const char *s = luaL_checklstring(L, 1, &ls);
+  const char *p = luaL_checklstring(L, 2, &lp);
+  size_t init = posrelatI(luaL_optinteger(L, 3, 1), ls) - 1;
+  if (init > ls) {  /* start after string's end? */
+    luaL_pushfail(L);  /* cannot find anything */
+    return 1;
+  }
+  /* explicit request or no special characters? */
+  if (find && (lua_toboolean(L, 4) || nospecials(p, lp))) {
+    /* do a plain search */
+    const char *s2 = lmemfind(s + init, ls - init, p, lp);
+    if (s2) {
+      lua_pushinteger(L, (s2 - s) + 1);
+      lua_pushinteger(L, (s2 - s) + lp);
+      return 2;
+    }
+  }
+  else {
+    MatchState ms;
+    const char *s1 = s + init;
+    int anchor = (*p == '^');
+    if (anchor) {
+      p++; lp--;  /* skip anchor character */
+    }
+    prepstate(&ms, L, s, ls, p, lp);
+    do {
+      const char *res;
+      reprepstate(&ms);
+      if ((res=match(&ms, s1, p)) != NULL) {
+        if (find) {
+          lua_pushinteger(L, (s1 - s) + 1);  /* start */
+          lua_pushinteger(L, res - s);   /* end */
+          return push_captures(&ms, NULL, 0) + 2;
+        }
+        else
+          return push_captures(&ms, s1, res);
+      }
+    } while (s1++ < ms.src_end && !anchor);
+  }
+  luaL_pushfail(L);  /* not found */
+  return 1;
+}
+
+
+static int str_find (lua_State *L) {
+  return str_find_aux(L, 1);
+}
+
+
+static int str_match (lua_State *L) {
+  return str_find_aux(L, 0);
+}
+
+
+/* state for 'gmatch' */
+typedef struct GMatchState {
+  const char *src;  /* current position */
+  const char *p;  /* pattern */
+  const char *lastmatch;  /* end of last match */
+  MatchState ms;  /* match state */
+} GMatchState;
+
+
+static int gmatch_aux (lua_State *L) {
+  GMatchState *gm = (GMatchState *)lua_touserdata(L, lua_upvalueindex(3));
+  const char *src;
+  gm->ms.L = L;
+  for (src = gm->src; src <= gm->ms.src_end; src++) {
+    const char *e;
+    reprepstate(&gm->ms);
+    if ((e = match(&gm->ms, src, gm->p)) != NULL && e != gm->lastmatch) {
+      gm->src = gm->lastmatch = e;
+      return push_captures(&gm->ms, src, e);
+    }
+  }
+  return 0;  /* not found */
+}
+
+
+static int gmatch (lua_State *L) {
+  size_t ls, lp;
+  const char *s = luaL_checklstring(L, 1, &ls);
+  const char *p = luaL_checklstring(L, 2, &lp);
+  size_t init = posrelatI(luaL_optinteger(L, 3, 1), ls) - 1;
+  GMatchState *gm;
+  lua_settop(L, 2);  /* keep strings on closure to avoid being collected */
+  gm = (GMatchState *)lua_newuserdatauv(L, sizeof(GMatchState), 0);
+  if (init > ls)  /* start after string's end? */
+    init = ls + 1;  /* avoid overflows in 's + init' */
+  prepstate(&gm->ms, L, s, ls, p, lp);
+  gm->src = s + init; gm->p = p; gm->lastmatch = NULL;
+  lua_pushcclosure(L, gmatch_aux, 3);
+  return 1;
+}
+
+
+static void add_s (MatchState *ms, luaL_Buffer *b, const char *s,
+                                                   const char *e) {
+  size_t l;
+  lua_State *L = ms->L;
+  const char *news = lua_tolstring(L, 3, &l);
+  const char *p;
+  while ((p = (char *)memchr(news, L_ESC, l)) != NULL) {
+    luaL_addlstring(b, news, p - news);
+    p++;  /* skip ESC */
+    if (*p == L_ESC)  /* '%%' */
+      luaL_addchar(b, *p);
+    else if (*p == '0')  /* '%0' */
+        luaL_addlstring(b, s, e - s);
+    else if (isdigit(uchar(*p))) {  /* '%n' */
+      const char *cap;
+      ptrdiff_t resl = get_onecapture(ms, *p - '1', s, e, &cap);
+      if (resl == CAP_POSITION)
+        luaL_addvalue(b);  /* add position to accumulated result */
+      else
+        luaL_addlstring(b, cap, resl);
+    }
+    else
+      luaL_error(L, "invalid use of '%c' in replacement string", L_ESC);
+    l -= p + 1 - news;
+    news = p + 1;
+  }
+  luaL_addlstring(b, news, l);
+}
+
+
+/*
+** Add the replacement value to the string buffer 'b'.
+** Return true if the original string was changed. (Function calls and
+** table indexing resulting in nil or false do not change the subject.)
+*/
+static int add_value (MatchState *ms, luaL_Buffer *b, const char *s,
+                                      const char *e, int tr) {
+  lua_State *L = ms->L;
+  switch (tr) {
+    case LUA_TFUNCTION: {  /* call the function */
+      int n;
+      lua_pushvalue(L, 3);  /* push the function */
+      n = push_captures(ms, s, e);  /* all captures as arguments */
+      lua_call(L, n, 1);  /* call it */
+      break;
+    }
+    case LUA_TTABLE: {  /* index the table */
+      push_onecapture(ms, 0, s, e);  /* first capture is the index */
+      lua_gettable(L, 3);
+      break;
+    }
+    default: {  /* LUA_TNUMBER or LUA_TSTRING */
+      add_s(ms, b, s, e);  /* add value to the buffer */
+      return 1;  /* something changed */
+    }
+  }
+  if (!lua_toboolean(L, -1)) {  /* nil or false? */
+    lua_pop(L, 1);  /* remove value */
+    luaL_addlstring(b, s, e - s);  /* keep original text */
+    return 0;  /* no changes */
+  }
+  else if (!lua_isstring(L, -1))
+    return luaL_error(L, "invalid replacement value (a %s)",
+                         luaL_typename(L, -1));
+  else {
+    luaL_addvalue(b);  /* add result to accumulator */
+    return 1;  /* something changed */
+  }
+}
+
+
+static int str_gsub (lua_State *L) {
+  size_t srcl, lp;
+  const char *src = luaL_checklstring(L, 1, &srcl);  /* subject */
+  const char *p = luaL_checklstring(L, 2, &lp);  /* pattern */
+  const char *lastmatch = NULL;  /* end of last match */
+  int tr = lua_type(L, 3);  /* replacement type */
+  lua_Integer max_s = luaL_optinteger(L, 4, srcl + 1);  /* max replacements */
+  int anchor = (*p == '^');
+  lua_Integer n = 0;  /* replacement count */
+  int changed = 0;  /* change flag */
+  MatchState ms;
+  luaL_Buffer b;
+  luaL_argexpected(L, tr == LUA_TNUMBER || tr == LUA_TSTRING ||
+                   tr == LUA_TFUNCTION || tr == LUA_TTABLE, 3,
+                      "string/function/table");
+  luaL_buffinit(L, &b);
+  if (anchor) {
+    p++; lp--;  /* skip anchor character */
+  }
+  prepstate(&ms, L, src, srcl, p, lp);
+  while (n < max_s) {
+    const char *e;
+    reprepstate(&ms);  /* (re)prepare state for new match */
+    if ((e = match(&ms, src, p)) != NULL && e != lastmatch) {  /* match? */
+      n++;
+      changed = add_value(&ms, &b, src, e, tr) | changed;
+      src = lastmatch = e;
+    }
+    else if (src < ms.src_end)  /* otherwise, skip one character */
+      luaL_addchar(&b, *src++);
+    else break;  /* end of subject */
+    if (anchor) break;
+  }
+  if (!changed)  /* no changes? */
+    lua_pushvalue(L, 1);  /* return original string */
+  else {  /* something changed */
+    luaL_addlstring(&b, src, ms.src_end-src);
+    luaL_pushresult(&b);  /* create and return new string */
+  }
+  lua_pushinteger(L, n);  /* number of substitutions */
+  return 2;
+}
+
+/* }====================================================== */
+
+
+
+/*
+** {======================================================
+** STRING FORMAT
+** =======================================================
+*/
+
+#if !defined(lua_number2strx)	/* { */
+
+/*
+** Hexadecimal floating-point formatter
+*/
+
+#define SIZELENMOD	(sizeof(LUA_NUMBER_FRMLEN)/sizeof(char))
+
+
+/*
+** Number of bits that goes into the first digit. It can be any value
+** between 1 and 4; the following definition tries to align the number
+** to nibble boundaries by making what is left after that first digit a
+** multiple of 4.
+*/
+#define L_NBFD		((l_floatatt(MANT_DIG) - 1)%4 + 1)
+
+
+/*
+** Add integer part of 'x' to buffer and return new 'x'
+*/
+static lua_Number adddigit (char *buff, int n, lua_Number x) {
+  lua_Number dd = l_mathop(floor)(x);  /* get integer part from 'x' */
+  int d = (int)dd;
+  buff[n] = (d < 10 ? d + '0' : d - 10 + 'a');  /* add to buffer */
+  return x - dd;  /* return what is left */
+}
+
+
+static int num2straux (char *buff, int sz, lua_Number x) {
+  /* if 'inf' or 'NaN', format it like '%g' */
+  if (x != x || x == (lua_Number)HUGE_VAL || x == -(lua_Number)HUGE_VAL)
+    return l_sprintf(buff, sz, LUA_NUMBER_FMT, (LUAI_UACNUMBER)x);
+  else if (x == 0) {  /* can be -0... */
+    /* create "0" or "-0" followed by exponent */
+    return l_sprintf(buff, sz, LUA_NUMBER_FMT "x0p+0", (LUAI_UACNUMBER)x);
+  }
+  else {
+    int e;
+    lua_Number m = l_mathop(frexp)(x, &e);  /* 'x' fraction and exponent */
+    int n = 0;  /* character count */
+    if (m < 0) {  /* is number negative? */
+      buff[n++] = '-';  /* add sign */
+      m = -m;  /* make it positive */
+    }
+    buff[n++] = '0'; buff[n++] = 'x';  /* add "0x" */
+    m = adddigit(buff, n++, m * (1 << L_NBFD));  /* add first digit */
+    e -= L_NBFD;  /* this digit goes before the radix point */
+    if (m > 0) {  /* more digits? */
+      buff[n++] = lua_getlocaledecpoint();  /* add radix point */
+      do {  /* add as many digits as needed */
+        m = adddigit(buff, n++, m * 16);
+      } while (m > 0);
+    }
+    n += l_sprintf(buff + n, sz - n, "p%+d", e);  /* add exponent */
+    lua_assert(n < sz);
+    return n;
+  }
+}
+
+
+static int lua_number2strx (lua_State *L, char *buff, int sz,
+                            const char *fmt, lua_Number x) {
+  int n = num2straux(buff, sz, x);
+  if (fmt[SIZELENMOD] == 'A') {
+    int i;
+    for (i = 0; i < n; i++)
+      buff[i] = toupper(uchar(buff[i]));
+  }
+  else if (fmt[SIZELENMOD] != 'a')
+    return luaL_error(L, "modifiers for format '%%a'/'%%A' not implemented");
+  return n;
+}
+
+#endif				/* } */
+
+
+/*
+** Maximum size for items formatted with '%f'. This size is produced
+** by format('%.99f', -maxfloat), and is equal to 99 + 3 ('-', '.',
+** and '\0') + number of decimal digits to represent maxfloat (which
+** is maximum exponent + 1). (99+3+1, adding some extra, 110)
+*/
+#define MAX_ITEMF	(110 + l_floatatt(MAX_10_EXP))
+
+
+/*
+** All formats except '%f' do not need that large limit.  The other
+** float formats use exponents, so that they fit in the 99 limit for
+** significant digits; 's' for large strings and 'q' add items directly
+** to the buffer; all integer formats also fit in the 99 limit.  The
+** worst case are floats: they may need 99 significant digits, plus
+** '0x', '-', '.', 'e+XXXX', and '\0'. Adding some extra, 120.
+*/
+#define MAX_ITEM	120
+
+
+/* valid flags in a format specification */
+#if !defined(L_FMTFLAGS)
+#define L_FMTFLAGS	"-+ #0"
+#endif
+
+
+/*
+** maximum size of each format specification (such as "%-099.99d")
+*/
+#define MAX_FORMAT	32
+
+
+static void addquoted (luaL_Buffer *b, const char *s, size_t len) {
+  luaL_addchar(b, '"');
+  while (len--) {
+    if (*s == '"' || *s == '\\' || *s == '\n') {
+      luaL_addchar(b, '\\');
+      luaL_addchar(b, *s);
+    }
+    else if (iscntrl(uchar(*s))) {
+      char buff[10];
+      if (!isdigit(uchar(*(s+1))))
+        l_sprintf(buff, sizeof(buff), "\\%d", (int)uchar(*s));
+      else
+        l_sprintf(buff, sizeof(buff), "\\%03d", (int)uchar(*s));
+      luaL_addstring(b, buff);
+    }
+    else
+      luaL_addchar(b, *s);
+    s++;
+  }
+  luaL_addchar(b, '"');
+}
+
+
+/*
+** Serialize a floating-point number in such a way that it can be
+** scanned back by Lua. Use hexadecimal format for "common" numbers
+** (to preserve precision); inf, -inf, and NaN are handled separately.
+** (NaN cannot be expressed as a numeral, so we write '(0/0)' for it.)
+*/
+static int quotefloat (lua_State *L, char *buff, lua_Number n) {
+  const char *s;  /* for the fixed representations */
+  if (n == (lua_Number)HUGE_VAL)  /* inf? */
+    s = "1e9999";
+  else if (n == -(lua_Number)HUGE_VAL)  /* -inf? */
+    s = "-1e9999";
+  else if (n != n)  /* NaN? */
+    s = "(0/0)";
+  else {  /* format number as hexadecimal */
+    int  nb = lua_number2strx(L, buff, MAX_ITEM,
+                                 "%" LUA_NUMBER_FRMLEN "a", n);
+    /* ensures that 'buff' string uses a dot as the radix character */
+    if (memchr(buff, '.', nb) == NULL) {  /* no dot? */
+      char point = lua_getlocaledecpoint();  /* try locale point */
+      char *ppoint = (char *)memchr(buff, point, nb);
+      if (ppoint) *ppoint = '.';  /* change it to a dot */
+    }
+    return nb;
+  }
+  /* for the fixed representations */
+  return l_sprintf(buff, MAX_ITEM, "%s", s);
+}
+
+
+static void addliteral (lua_State *L, luaL_Buffer *b, int arg) {
+  switch (lua_type(L, arg)) {
+    case LUA_TSTRING: {
+      size_t len;
+      const char *s = lua_tolstring(L, arg, &len);
+      addquoted(b, s, len);
+      break;
+    }
+    case LUA_TNUMBER: {
+      char *buff = luaL_prepbuffsize(b, MAX_ITEM);
+      int nb;
+      if (!lua_isinteger(L, arg))  /* float? */
+        nb = quotefloat(L, buff, lua_tonumber(L, arg));
+      else {  /* integers */
+        lua_Integer n = lua_tointeger(L, arg);
+        const char *format = (n == LUA_MININTEGER)  /* corner case? */
+                           ? "0x%" LUA_INTEGER_FRMLEN "x"  /* use hex */
+                           : LUA_INTEGER_FMT;  /* else use default format */
+        nb = l_sprintf(buff, MAX_ITEM, format, (LUAI_UACINT)n);
+      }
+      luaL_addsize(b, nb);
+      break;
+    }
+    case LUA_TNIL: case LUA_TBOOLEAN: {
+      luaL_tolstring(L, arg, NULL);
+      luaL_addvalue(b);
+      break;
+    }
+    default: {
+      luaL_argerror(L, arg, "value has no literal form");
+    }
+  }
+}
+
+
+static const char *scanformat (lua_State *L, const char *strfrmt, char *form) {
+  const char *p = strfrmt;
+  while (*p != '\0' && strchr(L_FMTFLAGS, *p) != NULL) p++;  /* skip flags */
+  if ((size_t)(p - strfrmt) >= sizeof(L_FMTFLAGS)/sizeof(char))
+    luaL_error(L, "invalid format (repeated flags)");
+  if (isdigit(uchar(*p))) p++;  /* skip width */
+  if (isdigit(uchar(*p))) p++;  /* (2 digits at most) */
+  if (*p == '.') {
+    p++;
+    if (isdigit(uchar(*p))) p++;  /* skip precision */
+    if (isdigit(uchar(*p))) p++;  /* (2 digits at most) */
+  }
+  if (isdigit(uchar(*p)))
+    luaL_error(L, "invalid format (width or precision too long)");
+  *(form++) = '%';
+  memcpy(form, strfrmt, ((p - strfrmt) + 1) * sizeof(char));
+  form += (p - strfrmt) + 1;
+  *form = '\0';
+  return p;
+}
+
+
+/*
+** add length modifier into formats
+*/
+static void addlenmod (char *form, const char *lenmod) {
+  size_t l = strlen(form);
+  size_t lm = strlen(lenmod);
+  char spec = form[l - 1];
+  strcpy(form + l - 1, lenmod);
+  form[l + lm - 1] = spec;
+  form[l + lm] = '\0';
+}
+
+
+static int str_format (lua_State *L) {
+  int top = lua_gettop(L);
+  int arg = 1;
+  size_t sfl;
+  const char *strfrmt = luaL_checklstring(L, arg, &sfl);
+  const char *strfrmt_end = strfrmt+sfl;
+  luaL_Buffer b;
+  luaL_buffinit(L, &b);
+  while (strfrmt < strfrmt_end) {
+    if (*strfrmt != L_ESC)
+      luaL_addchar(&b, *strfrmt++);
+    else if (*++strfrmt == L_ESC)
+      luaL_addchar(&b, *strfrmt++);  /* %% */
+    else { /* format item */
+      char form[MAX_FORMAT];  /* to store the format ('%...') */
+      int maxitem = MAX_ITEM;
+      char *buff = luaL_prepbuffsize(&b, maxitem);  /* to put formatted item */
+      int nb = 0;  /* number of bytes in added item */
+      if (++arg > top)
+        return luaL_argerror(L, arg, "no value");
+      strfrmt = scanformat(L, strfrmt, form);
+      switch (*strfrmt++) {
+        case 'c': {
+          nb = l_sprintf(buff, maxitem, form, (int)luaL_checkinteger(L, arg));
+          break;
+        }
+        case 'd': case 'i':
+        case 'o': case 'u': case 'x': case 'X': {
+          lua_Integer n = luaL_checkinteger(L, arg);
+          addlenmod(form, LUA_INTEGER_FRMLEN);
+          nb = l_sprintf(buff, maxitem, form, (LUAI_UACINT)n);
+          break;
+        }
+        case 'a': case 'A':
+          addlenmod(form, LUA_NUMBER_FRMLEN);
+          nb = lua_number2strx(L, buff, maxitem, form,
+                                  luaL_checknumber(L, arg));
+          break;
+        case 'f':
+          maxitem = MAX_ITEMF;  /* extra space for '%f' */
+          buff = luaL_prepbuffsize(&b, maxitem);
+          /* FALLTHROUGH */
+        case 'e': case 'E': case 'g': case 'G': {
+          lua_Number n = luaL_checknumber(L, arg);
+          addlenmod(form, LUA_NUMBER_FRMLEN);
+          nb = l_sprintf(buff, maxitem, form, (LUAI_UACNUMBER)n);
+          break;
+        }
+        case 'p': {
+          const void *p = lua_topointer(L, arg);
+          if (p == NULL) {  /* avoid calling 'printf' with argument NULL */
+            p = "(null)";  /* result */
+            form[strlen(form) - 1] = 's';  /* format it as a string */
+          }
+          nb = l_sprintf(buff, maxitem, form, p);
+          break;
+        }
+        case 'q': {
+          if (form[2] != '\0')  /* modifiers? */
+            return luaL_error(L, "specifier '%%q' cannot have modifiers");
+          addliteral(L, &b, arg);
+          break;
+        }
+        case 's': {
+          size_t l;
+          const char *s = luaL_tolstring(L, arg, &l);
+          if (form[2] == '\0')  /* no modifiers? */
+            luaL_addvalue(&b);  /* keep entire string */
+          else {
+            luaL_argcheck(L, l == strlen(s), arg, "string contains zeros");
+            if (!strchr(form, '.') && l >= 100) {
+              /* no precision and string is too long to be formatted */
+              luaL_addvalue(&b);  /* keep entire string */
+            }
+            else {  /* format the string into 'buff' */
+              nb = l_sprintf(buff, maxitem, form, s);
+              lua_pop(L, 1);  /* remove result from 'luaL_tolstring' */
+            }
+          }
+          break;
+        }
+        default: {  /* also treat cases 'pnLlh' */
+          return luaL_error(L, "invalid conversion '%s' to 'format'", form);
+        }
+      }
+      lua_assert(nb < maxitem);
+      luaL_addsize(&b, nb);
+    }
+  }
+  luaL_pushresult(&b);
+  return 1;
+}
+
+/* }====================================================== */
+
+
+/*
+** {======================================================
+** PACK/UNPACK
+** =======================================================
+*/
+
+
+/* value used for padding */
+#if !defined(LUAL_PACKPADBYTE)
+#define LUAL_PACKPADBYTE		0x00
+#endif
+
+/* maximum size for the binary representation of an integer */
+#define MAXINTSIZE	16
+
+/* number of bits in a character */
+#define NB	CHAR_BIT
+
+/* mask for one character (NB 1's) */
+#define MC	((1 << NB) - 1)
+
+/* size of a lua_Integer */
+#define SZINT	((int)sizeof(lua_Integer))
+
+
+/* dummy union to get native endianness */
+static const union {
+  int dummy;
+  char little;  /* true iff machine is little endian */
+} nativeendian = {1};
+
+
+/* dummy structure to get native alignment requirements */
+struct cD {
+  char c;
+  union { double d; void *p; lua_Integer i; lua_Number n; } u;
+};
+
+#define MAXALIGN	(offsetof(struct cD, u))
+
+
+/*
+** Union for serializing floats
+*/
+typedef union Ftypes {
+  float f;
+  double d;
+  lua_Number n;
+  char buff[5 * sizeof(lua_Number)];  /* enough for any float type */
+} Ftypes;
+
+
+/*
+** information to pack/unpack stuff
+*/
+typedef struct Header {
+  lua_State *L;
+  int islittle;
+  int maxalign;
+} Header;
+
+
+/*
+** options for pack/unpack
+*/
+typedef enum KOption {
+  Kint,		/* signed integers */
+  Kuint,	/* unsigned integers */
+  Kfloat,	/* floating-point numbers */
+  Kchar,	/* fixed-length strings */
+  Kstring,	/* strings with prefixed length */
+  Kzstr,	/* zero-terminated strings */
+  Kpadding,	/* padding */
+  Kpaddalign,	/* padding for alignment */
+  Knop		/* no-op (configuration or spaces) */
+} KOption;
+
+
+/*
+** Read an integer numeral from string 'fmt' or return 'df' if
+** there is no numeral
+*/
+static int digit (int c) { return '0' <= c && c <= '9'; }
+
+static int getnum (const char **fmt, int df) {
+  if (!digit(**fmt))  /* no number? */
+    return df;  /* return default value */
+  else {
+    int a = 0;
+    do {
+      a = a*10 + (*((*fmt)++) - '0');
+    } while (digit(**fmt) && a <= ((int)MAXSIZE - 9)/10);
+    return a;
+  }
+}
+
+
+/*
+** Read an integer numeral and raises an error if it is larger
+** than the maximum size for integers.
+*/
+static int getnumlimit (Header *h, const char **fmt, int df) {
+  int sz = getnum(fmt, df);
+  if (sz > MAXINTSIZE || sz <= 0)
+    return luaL_error(h->L, "integral size (%d) out of limits [1,%d]",
+                            sz, MAXINTSIZE);
+  return sz;
+}
+
+
+/*
+** Initialize Header
+*/
+static void initheader (lua_State *L, Header *h) {
+  h->L = L;
+  h->islittle = nativeendian.little;
+  h->maxalign = 1;
+}
+
+
+/*
+** Read and classify next option. 'size' is filled with option's size.
+*/
+static KOption getoption (Header *h, const char **fmt, int *size) {
+  int opt = *((*fmt)++);
+  *size = 0;  /* default */
+  switch (opt) {
+    case 'b': *size = sizeof(char); return Kint;
+    case 'B': *size = sizeof(char); return Kuint;
+    case 'h': *size = sizeof(short); return Kint;
+    case 'H': *size = sizeof(short); return Kuint;
+    case 'l': *size = sizeof(long); return Kint;
+    case 'L': *size = sizeof(long); return Kuint;
+    case 'j': *size = sizeof(lua_Integer); return Kint;
+    case 'J': *size = sizeof(lua_Integer); return Kuint;
+    case 'T': *size = sizeof(size_t); return Kuint;
+    case 'f': *size = sizeof(float); return Kfloat;
+    case 'd': *size = sizeof(double); return Kfloat;
+    case 'n': *size = sizeof(lua_Number); return Kfloat;
+    case 'i': *size = getnumlimit(h, fmt, sizeof(int)); return Kint;
+    case 'I': *size = getnumlimit(h, fmt, sizeof(int)); return Kuint;
+    case 's': *size = getnumlimit(h, fmt, sizeof(size_t)); return Kstring;
+    case 'c':
+      *size = getnum(fmt, -1);
+      if (*size == -1)
+        luaL_error(h->L, "missing size for format option 'c'");
+      return Kchar;
+    case 'z': return Kzstr;
+    case 'x': *size = 1; return Kpadding;
+    case 'X': return Kpaddalign;
+    case ' ': break;
+    case '<': h->islittle = 1; break;
+    case '>': h->islittle = 0; break;
+    case '=': h->islittle = nativeendian.little; break;
+    case '!': h->maxalign = getnumlimit(h, fmt, MAXALIGN); break;
+    default: luaL_error(h->L, "invalid format option '%c'", opt);
+  }
+  return Knop;
+}
+
+
+/*
+** Read, classify, and fill other details about the next option.
+** 'psize' is filled with option's size, 'notoalign' with its
+** alignment requirements.
+** Local variable 'size' gets the size to be aligned. (Kpadal option
+** always gets its full alignment, other options are limited by
+** the maximum alignment ('maxalign'). Kchar option needs no alignment
+** despite its size.
+*/
+static KOption getdetails (Header *h, size_t totalsize,
+                           const char **fmt, int *psize, int *ntoalign) {
+  KOption opt = getoption(h, fmt, psize);
+  int align = *psize;  /* usually, alignment follows size */
+  if (opt == Kpaddalign) {  /* 'X' gets alignment from following option */
+    if (**fmt == '\0' || getoption(h, fmt, &align) == Kchar || align == 0)
+      luaL_argerror(h->L, 1, "invalid next option for option 'X'");
+  }
+  if (align <= 1 || opt == Kchar)  /* need no alignment? */
+    *ntoalign = 0;
+  else {
+    if (align > h->maxalign)  /* enforce maximum alignment */
+      align = h->maxalign;
+    if ((align & (align - 1)) != 0)  /* is 'align' not a power of 2? */
+      luaL_argerror(h->L, 1, "format asks for alignment not power of 2");
+    *ntoalign = (align - (int)(totalsize & (align - 1))) & (align - 1);
+  }
+  return opt;
+}
+
+
+/*
+** Pack integer 'n' with 'size' bytes and 'islittle' endianness.
+** The final 'if' handles the case when 'size' is larger than
+** the size of a Lua integer, correcting the extra sign-extension
+** bytes if necessary (by default they would be zeros).
+*/
+static void packint (luaL_Buffer *b, lua_Unsigned n,
+                     int islittle, int size, int neg) {
+  char *buff = luaL_prepbuffsize(b, size);
+  int i;
+  buff[islittle ? 0 : size - 1] = (char)(n & MC);  /* first byte */
+  for (i = 1; i < size; i++) {
+    n >>= NB;
+    buff[islittle ? i : size - 1 - i] = (char)(n & MC);
+  }
+  if (neg && size > SZINT) {  /* negative number need sign extension? */
+    for (i = SZINT; i < size; i++)  /* correct extra bytes */
+      buff[islittle ? i : size - 1 - i] = (char)MC;
+  }
+  luaL_addsize(b, size);  /* add result to buffer */
+}
+
+
+/*
+** Copy 'size' bytes from 'src' to 'dest', correcting endianness if
+** given 'islittle' is different from native endianness.
+*/
+static void copywithendian (volatile char *dest, volatile const char *src,
+                            int size, int islittle) {
+  if (islittle == nativeendian.little) {
+    while (size-- != 0)
+      *(dest++) = *(src++);
+  }
+  else {
+    dest += size - 1;
+    while (size-- != 0)
+      *(dest--) = *(src++);
+  }
+}
+
+
+static int str_pack (lua_State *L) {
+  luaL_Buffer b;
+  Header h;
+  const char *fmt = luaL_checkstring(L, 1);  /* format string */
+  int arg = 1;  /* current argument to pack */
+  size_t totalsize = 0;  /* accumulate total size of result */
+  initheader(L, &h);
+  lua_pushnil(L);  /* mark to separate arguments from string buffer */
+  luaL_buffinit(L, &b);
+  while (*fmt != '\0') {
+    int size, ntoalign;
+    KOption opt = getdetails(&h, totalsize, &fmt, &size, &ntoalign);
+    totalsize += ntoalign + size;
+    while (ntoalign-- > 0)
+     luaL_addchar(&b, LUAL_PACKPADBYTE);  /* fill alignment */
+    arg++;
+    switch (opt) {
+      case Kint: {  /* signed integers */
+        lua_Integer n = luaL_checkinteger(L, arg);
+        if (size < SZINT) {  /* need overflow check? */
+          lua_Integer lim = (lua_Integer)1 << ((size * NB) - 1);
+          luaL_argcheck(L, -lim <= n && n < lim, arg, "integer overflow");
+        }
+        packint(&b, (lua_Unsigned)n, h.islittle, size, (n < 0));
+        break;
+      }
+      case Kuint: {  /* unsigned integers */
+        lua_Integer n = luaL_checkinteger(L, arg);
+        if (size < SZINT)  /* need overflow check? */
+          luaL_argcheck(L, (lua_Unsigned)n < ((lua_Unsigned)1 << (size * NB)),
+                           arg, "unsigned overflow");
+        packint(&b, (lua_Unsigned)n, h.islittle, size, 0);
+        break;
+      }
+      case Kfloat: {  /* floating-point options */
+        volatile Ftypes u;
+        char *buff = luaL_prepbuffsize(&b, size);
+        lua_Number n = luaL_checknumber(L, arg);  /* get argument */
+        if (size == sizeof(u.f)) u.f = (float)n;  /* copy it into 'u' */
+        else if (size == sizeof(u.d)) u.d = (double)n;
+        else u.n = n;
+        /* move 'u' to final result, correcting endianness if needed */
+        copywithendian(buff, u.buff, size, h.islittle);
+        luaL_addsize(&b, size);
+        break;
+      }
+      case Kchar: {  /* fixed-size string */
+        size_t len;
+        const char *s = luaL_checklstring(L, arg, &len);
+        luaL_argcheck(L, len <= (size_t)size, arg,
+                         "string longer than given size");
+        luaL_addlstring(&b, s, len);  /* add string */
+        while (len++ < (size_t)size)  /* pad extra space */
+          luaL_addchar(&b, LUAL_PACKPADBYTE);
+        break;
+      }
+      case Kstring: {  /* strings with length count */
+        size_t len;
+        const char *s = luaL_checklstring(L, arg, &len);
+        luaL_argcheck(L, size >= (int)sizeof(size_t) ||
+                         len < ((size_t)1 << (size * NB)),
+                         arg, "string length does not fit in given size");
+        packint(&b, (lua_Unsigned)len, h.islittle, size, 0);  /* pack length */
+        luaL_addlstring(&b, s, len);
+        totalsize += len;
+        break;
+      }
+      case Kzstr: {  /* zero-terminated string */
+        size_t len;
+        const char *s = luaL_checklstring(L, arg, &len);
+        luaL_argcheck(L, strlen(s) == len, arg, "string contains zeros");
+        luaL_addlstring(&b, s, len);
+        luaL_addchar(&b, '\0');  /* add zero at the end */
+        totalsize += len + 1;
+        break;
+      }
+      case Kpadding: luaL_addchar(&b, LUAL_PACKPADBYTE);  /* FALLTHROUGH */
+      case Kpaddalign: case Knop:
+        arg--;  /* undo increment */
+        break;
+    }
+  }
+  luaL_pushresult(&b);
+  return 1;
+}
+
+
+static int str_packsize (lua_State *L) {
+  Header h;
+  const char *fmt = luaL_checkstring(L, 1);  /* format string */
+  size_t totalsize = 0;  /* accumulate total size of result */
+  initheader(L, &h);
+  while (*fmt != '\0') {
+    int size, ntoalign;
+    KOption opt = getdetails(&h, totalsize, &fmt, &size, &ntoalign);
+    luaL_argcheck(L, opt != Kstring && opt != Kzstr, 1,
+                     "variable-length format");
+    size += ntoalign;  /* total space used by option */
+    luaL_argcheck(L, totalsize <= MAXSIZE - size, 1,
+                     "format result too large");
+    totalsize += size;
+  }
+  lua_pushinteger(L, (lua_Integer)totalsize);
+  return 1;
+}
+
+
+/*
+** Unpack an integer with 'size' bytes and 'islittle' endianness.
+** If size is smaller than the size of a Lua integer and integer
+** is signed, must do sign extension (propagating the sign to the
+** higher bits); if size is larger than the size of a Lua integer,
+** it must check the unread bytes to see whether they do not cause an
+** overflow.
+*/
+static lua_Integer unpackint (lua_State *L, const char *str,
+                              int islittle, int size, int issigned) {
+  lua_Unsigned res = 0;
+  int i;
+  int limit = (size  <= SZINT) ? size : SZINT;
+  for (i = limit - 1; i >= 0; i--) {
+    res <<= NB;
+    res |= (lua_Unsigned)(unsigned char)str[islittle ? i : size - 1 - i];
+  }
+  if (size < SZINT) {  /* real size smaller than lua_Integer? */
+    if (issigned) {  /* needs sign extension? */
+      lua_Unsigned mask = (lua_Unsigned)1 << (size*NB - 1);
+      res = ((res ^ mask) - mask);  /* do sign extension */
+    }
+  }
+  else if (size > SZINT) {  /* must check unread bytes */
+    int mask = (!issigned || (lua_Integer)res >= 0) ? 0 : MC;
+    for (i = limit; i < size; i++) {
+      if ((unsigned char)str[islittle ? i : size - 1 - i] != mask)
+        luaL_error(L, "%d-byte integer does not fit into Lua Integer", size);
+    }
+  }
+  return (lua_Integer)res;
+}
+
+
+static int str_unpack (lua_State *L) {
+  Header h;
+  const char *fmt = luaL_checkstring(L, 1);
+  size_t ld;
+  const char *data = luaL_checklstring(L, 2, &ld);
+  size_t pos = posrelatI(luaL_optinteger(L, 3, 1), ld) - 1;
+  int n = 0;  /* number of results */
+  luaL_argcheck(L, pos <= ld, 3, "initial position out of string");
+  initheader(L, &h);
+  while (*fmt != '\0') {
+    int size, ntoalign;
+    KOption opt = getdetails(&h, pos, &fmt, &size, &ntoalign);
+    luaL_argcheck(L, (size_t)ntoalign + size <= ld - pos, 2,
+                    "data string too short");
+    pos += ntoalign;  /* skip alignment */
+    /* stack space for item + next position */
+    luaL_checkstack(L, 2, "too many results");
+    n++;
+    switch (opt) {
+      case Kint:
+      case Kuint: {
+        lua_Integer res = unpackint(L, data + pos, h.islittle, size,
+                                       (opt == Kint));
+        lua_pushinteger(L, res);
+        break;
+      }
+      case Kfloat: {
+        volatile Ftypes u;
+        lua_Number num;
+        copywithendian(u.buff, data + pos, size, h.islittle);
+        if (size == sizeof(u.f)) num = (lua_Number)u.f;
+        else if (size == sizeof(u.d)) num = (lua_Number)u.d;
+        else num = u.n;
+        lua_pushnumber(L, num);
+        break;
+      }
+      case Kchar: {
+        lua_pushlstring(L, data + pos, size);
+        break;
+      }
+      case Kstring: {
+        size_t len = (size_t)unpackint(L, data + pos, h.islittle, size, 0);
+        luaL_argcheck(L, len <= ld - pos - size, 2, "data string too short");
+        lua_pushlstring(L, data + pos + size, len);
+        pos += len;  /* skip string */
+        break;
+      }
+      case Kzstr: {
+        size_t len = (int)strlen(data + pos);
+        luaL_argcheck(L, pos + len < ld, 2,
+                         "unfinished string for format 'z'");
+        lua_pushlstring(L, data + pos, len);
+        pos += len + 1;  /* skip string plus final '\0' */
+        break;
+      }
+      case Kpaddalign: case Kpadding: case Knop:
+        n--;  /* undo increment */
+        break;
+    }
+    pos += size;
+  }
+  lua_pushinteger(L, pos + 1);  /* next position */
+  return n + 1;
+}
+
+/* }====================================================== */
+
+
+static const luaL_Reg strlib[] = {
+  {"byte", str_byte},
+  {"char", str_char},
+  {"dump", str_dump},
+  {"find", str_find},
+  {"format", str_format},
+  {"gmatch", gmatch},
+  {"gsub", str_gsub},
+  {"len", str_len},
+  {"lower", str_lower},
+  {"match", str_match},
+  {"rep", str_rep},
+  {"reverse", str_reverse},
+  {"sub", str_sub},
+  {"upper", str_upper},
+  {"pack", str_pack},
+  {"packsize", str_packsize},
+  {"unpack", str_unpack},
+  {NULL, NULL}
+};
+
+
+static void createmetatable (lua_State *L) {
+  /* table to be metatable for strings */
+  luaL_newlibtable(L, stringmetamethods);
+  luaL_setfuncs(L, stringmetamethods, 0);
+  lua_pushliteral(L, "");  /* dummy string */
+  lua_pushvalue(L, -2);  /* copy table */
+  lua_setmetatable(L, -2);  /* set table as metatable for strings */
+  lua_pop(L, 1);  /* pop dummy string */
+  lua_pushvalue(L, -2);  /* get string library */
+  lua_setfield(L, -2, "__index");  /* metatable.__index = string */
+  lua_pop(L, 1);  /* pop metatable */
+}
+
+
+/*
+** Open string library
+*/
+LUAMOD_API int luaopen_string (lua_State *L) {
+  luaL_newlib(L, strlib);
+  createmetatable(L);
+  return 1;
+}
+
diff --git a/test/external/lua-5.4.0/src/ltable.c b/test/external/lua-5.4.0/src/ltable.c
new file mode 100644
index 0000000..d7eb69a
--- /dev/null
+++ b/test/external/lua-5.4.0/src/ltable.c
@@ -0,0 +1,924 @@
+/*
+** $Id: ltable.c $
+** Lua tables (hash)
+** See Copyright Notice in lua.h
+*/
+
+#define ltable_c
+#define LUA_CORE
+
+#include "lprefix.h"
+
+
+/*
+** Implementation of tables (aka arrays, objects, or hash tables).
+** Tables keep its elements in two parts: an array part and a hash part.
+** Non-negative integer keys are all candidates to be kept in the array
+** part. The actual size of the array is the largest 'n' such that
+** more than half the slots between 1 and n are in use.
+** Hash uses a mix of chained scatter table with Brent's variation.
+** A main invariant of these tables is that, if an element is not
+** in its main position (i.e. the 'original' position that its hash gives
+** to it), then the colliding element is in its own main position.
+** Hence even when the load factor reaches 100%, performance remains good.
+*/
+
+#include <math.h>
+#include <limits.h>
+
+#include "lua.h"
+
+#include "ldebug.h"
+#include "ldo.h"
+#include "lgc.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "lvm.h"
+
+
+/*
+** MAXABITS is the largest integer such that MAXASIZE fits in an
+** unsigned int.
+*/
+#define MAXABITS	cast_int(sizeof(int) * CHAR_BIT - 1)
+
+
+/*
+** MAXASIZE is the maximum size of the array part. It is the minimum
+** between 2^MAXABITS and the maximum size that, measured in bytes,
+** fits in a 'size_t'.
+*/
+#define MAXASIZE	luaM_limitN(1u << MAXABITS, TValue)
+
+/*
+** MAXHBITS is the largest integer such that 2^MAXHBITS fits in a
+** signed int.
+*/
+#define MAXHBITS	(MAXABITS - 1)
+
+
+/*
+** MAXHSIZE is the maximum size of the hash part. It is the minimum
+** between 2^MAXHBITS and the maximum size such that, measured in bytes,
+** it fits in a 'size_t'.
+*/
+#define MAXHSIZE	luaM_limitN(1u << MAXHBITS, Node)
+
+
+#define hashpow2(t,n)		(gnode(t, lmod((n), sizenode(t))))
+
+#define hashstr(t,str)		hashpow2(t, (str)->hash)
+#define hashboolean(t,p)	hashpow2(t, p)
+#define hashint(t,i)		hashpow2(t, i)
+
+
+/*
+** for some types, it is better to avoid modulus by power of 2, as
+** they tend to have many 2 factors.
+*/
+#define hashmod(t,n)	(gnode(t, ((n) % ((sizenode(t)-1)|1))))
+
+
+#define hashpointer(t,p)	hashmod(t, point2uint(p))
+
+
+#define dummynode		(&dummynode_)
+
+static const Node dummynode_ = {
+  {{NULL}, LUA_VEMPTY,  /* value's value and type */
+   LUA_VNIL, 0, {NULL}}  /* key type, next, and key value */
+};
+
+
+static const TValue absentkey = {ABSTKEYCONSTANT};
+
+
+
+/*
+** Hash for floating-point numbers.
+** The main computation should be just
+**     n = frexp(n, &i); return (n * INT_MAX) + i
+** but there are some numerical subtleties.
+** In a two-complement representation, INT_MAX does not has an exact
+** representation as a float, but INT_MIN does; because the absolute
+** value of 'frexp' is smaller than 1 (unless 'n' is inf/NaN), the
+** absolute value of the product 'frexp * -INT_MIN' is smaller or equal
+** to INT_MAX. Next, the use of 'unsigned int' avoids overflows when
+** adding 'i'; the use of '~u' (instead of '-u') avoids problems with
+** INT_MIN.
+*/
+#if !defined(l_hashfloat)
+static int l_hashfloat (lua_Number n) {
+  int i;
+  lua_Integer ni;
+  n = l_mathop(frexp)(n, &i) * -cast_num(INT_MIN);
+  if (!lua_numbertointeger(n, &ni)) {  /* is 'n' inf/-inf/NaN? */
+    lua_assert(luai_numisnan(n) || l_mathop(fabs)(n) == cast_num(HUGE_VAL));
+    return 0;
+  }
+  else {  /* normal case */
+    unsigned int u = cast_uint(i) + cast_uint(ni);
+    return cast_int(u <= cast_uint(INT_MAX) ? u : ~u);
+  }
+}
+#endif
+
+
+/*
+** returns the 'main' position of an element in a table (that is,
+** the index of its hash value). The key comes broken (tag in 'ktt'
+** and value in 'vkl') so that we can call it on keys inserted into
+** nodes.
+*/
+static Node *mainposition (const Table *t, int ktt, const Value *kvl) {
+  switch (withvariant(ktt)) {
+    case LUA_VNUMINT:
+      return hashint(t, ivalueraw(*kvl));
+    case LUA_VNUMFLT:
+      return hashmod(t, l_hashfloat(fltvalueraw(*kvl)));
+    case LUA_VSHRSTR:
+      return hashstr(t, tsvalueraw(*kvl));
+    case LUA_VLNGSTR:
+      return hashpow2(t, luaS_hashlongstr(tsvalueraw(*kvl)));
+    case LUA_VFALSE:
+      return hashboolean(t, 0);
+    case LUA_VTRUE:
+      return hashboolean(t, 1);
+    case LUA_VLIGHTUSERDATA:
+      return hashpointer(t, pvalueraw(*kvl));
+    case LUA_VLCF:
+      return hashpointer(t, fvalueraw(*kvl));
+    default:
+      return hashpointer(t, gcvalueraw(*kvl));
+  }
+}
+
+
+/*
+** Returns the main position of an element given as a 'TValue'
+*/
+static Node *mainpositionTV (const Table *t, const TValue *key) {
+  return mainposition(t, rawtt(key), valraw(key));
+}
+
+
+/*
+** Check whether key 'k1' is equal to the key in node 'n2'.
+** This equality is raw, so there are no metamethods. Floats
+** with integer values have been normalized, so integers cannot
+** be equal to floats. It is assumed that 'eqshrstr' is simply
+** pointer equality, so that short strings are handled in the
+** default case.
+*/
+static int equalkey (const TValue *k1, const Node *n2) {
+  if (rawtt(k1) != keytt(n2))  /* not the same variants? */
+   return 0;  /* cannot be same key */
+  switch (ttypetag(k1)) {
+    case LUA_VNIL: case LUA_VFALSE: case LUA_VTRUE:
+      return 1;
+    case LUA_VNUMINT:
+      return (ivalue(k1) == keyival(n2));
+    case LUA_VNUMFLT:
+      return luai_numeq(fltvalue(k1), fltvalueraw(keyval(n2)));
+    case LUA_VLIGHTUSERDATA:
+      return pvalue(k1) == pvalueraw(keyval(n2));
+    case LUA_VLCF:
+      return fvalue(k1) == fvalueraw(keyval(n2));
+    case LUA_VLNGSTR:
+      return luaS_eqlngstr(tsvalue(k1), keystrval(n2));
+    default:
+      return gcvalue(k1) == gcvalueraw(keyval(n2));
+  }
+}
+
+
+/*
+** True if value of 'alimit' is equal to the real size of the array
+** part of table 't'. (Otherwise, the array part must be larger than
+** 'alimit'.)
+*/
+#define limitequalsasize(t)	(isrealasize(t) || ispow2((t)->alimit))
+
+
+/*
+** Returns the real size of the 'array' array
+*/
+LUAI_FUNC unsigned int luaH_realasize (const Table *t) {
+  if (limitequalsasize(t))
+    return t->alimit;  /* this is the size */
+  else {
+    unsigned int size = t->alimit;
+    /* compute the smallest power of 2 not smaller than 'n' */
+    size |= (size >> 1);
+    size |= (size >> 2);
+    size |= (size >> 4);
+    size |= (size >> 8);
+    size |= (size >> 16);
+#if (UINT_MAX >> 30) > 3
+    size |= (size >> 32);  /* unsigned int has more than 32 bits */
+#endif
+    size++;
+    lua_assert(ispow2(size) && size/2 < t->alimit && t->alimit < size);
+    return size;
+  }
+}
+
+
+/*
+** Check whether real size of the array is a power of 2.
+** (If it is not, 'alimit' cannot be changed to any other value
+** without changing the real size.)
+*/
+static int ispow2realasize (const Table *t) {
+  return (!isrealasize(t) || ispow2(t->alimit));
+}
+
+
+static unsigned int setlimittosize (Table *t) {
+  t->alimit = luaH_realasize(t);
+  setrealasize(t);
+  return t->alimit;
+}
+
+
+#define limitasasize(t)	check_exp(isrealasize(t), t->alimit)
+
+
+
+/*
+** "Generic" get version. (Not that generic: not valid for integers,
+** which may be in array part, nor for floats with integral values.)
+*/
+static const TValue *getgeneric (Table *t, const TValue *key) {
+  Node *n = mainpositionTV(t, key);
+  for (;;) {  /* check whether 'key' is somewhere in the chain */
+    if (equalkey(key, n))
+      return gval(n);  /* that's it */
+    else {
+      int nx = gnext(n);
+      if (nx == 0)
+        return &absentkey;  /* not found */
+      n += nx;
+    }
+  }
+}
+
+
+/*
+** returns the index for 'k' if 'k' is an appropriate key to live in
+** the array part of a table, 0 otherwise.
+*/
+static unsigned int arrayindex (lua_Integer k) {
+  if (l_castS2U(k) - 1u < MAXASIZE)  /* 'k' in [1, MAXASIZE]? */
+    return cast_uint(k);  /* 'key' is an appropriate array index */
+  else
+    return 0;
+}
+
+
+/*
+** returns the index of a 'key' for table traversals. First goes all
+** elements in the array part, then elements in the hash part. The
+** beginning of a traversal is signaled by 0.
+*/
+static unsigned int findindex (lua_State *L, Table *t, TValue *key,
+                               unsigned int asize) {
+  unsigned int i;
+  if (ttisnil(key)) return 0;  /* first iteration */
+  i = ttisinteger(key) ? arrayindex(ivalue(key)) : 0;
+  if (i - 1u < asize)  /* is 'key' inside array part? */
+    return i;  /* yes; that's the index */
+  else {
+    const TValue *n = getgeneric(t, key);
+    if (unlikely(isabstkey(n)))
+      luaG_runerror(L, "invalid key to 'next'");  /* key not found */
+    i = cast_int(nodefromval(n) - gnode(t, 0));  /* key index in hash table */
+    /* hash elements are numbered after array ones */
+    return (i + 1) + asize;
+  }
+}
+
+
+int luaH_next (lua_State *L, Table *t, StkId key) {
+  unsigned int asize = luaH_realasize(t);
+  unsigned int i = findindex(L, t, s2v(key), asize);  /* find original key */
+  for (; i < asize; i++) {  /* try first array part */
+    if (!isempty(&t->array[i])) {  /* a non-empty entry? */
+      setivalue(s2v(key), i + 1);
+      setobj2s(L, key + 1, &t->array[i]);
+      return 1;
+    }
+  }
+  for (i -= asize; cast_int(i) < sizenode(t); i++) {  /* hash part */
+    if (!isempty(gval(gnode(t, i)))) {  /* a non-empty entry? */
+      Node *n = gnode(t, i);
+      getnodekey(L, s2v(key), n);
+      setobj2s(L, key + 1, gval(n));
+      return 1;
+    }
+  }
+  return 0;  /* no more elements */
+}
+
+
+static void freehash (lua_State *L, Table *t) {
+  if (!isdummy(t))
+    luaM_freearray(L, t->node, cast_sizet(sizenode(t)));
+}
+
+
+/*
+** {=============================================================
+** Rehash
+** ==============================================================
+*/
+
+/*
+** Compute the optimal size for the array part of table 't'. 'nums' is a
+** "count array" where 'nums[i]' is the number of integers in the table
+** between 2^(i - 1) + 1 and 2^i. 'pna' enters with the total number of
+** integer keys in the table and leaves with the number of keys that
+** will go to the array part; return the optimal size.  (The condition
+** 'twotoi > 0' in the for loop stops the loop if 'twotoi' overflows.)
+*/
+static unsigned int computesizes (unsigned int nums[], unsigned int *pna) {
+  int i;
+  unsigned int twotoi;  /* 2^i (candidate for optimal size) */
+  unsigned int a = 0;  /* number of elements smaller than 2^i */
+  unsigned int na = 0;  /* number of elements to go to array part */
+  unsigned int optimal = 0;  /* optimal size for array part */
+  /* loop while keys can fill more than half of total size */
+  for (i = 0, twotoi = 1;
+       twotoi > 0 && *pna > twotoi / 2;
+       i++, twotoi *= 2) {
+    a += nums[i];
+    if (a > twotoi/2) {  /* more than half elements present? */
+      optimal = twotoi;  /* optimal size (till now) */
+      na = a;  /* all elements up to 'optimal' will go to array part */
+    }
+  }
+  lua_assert((optimal == 0 || optimal / 2 < na) && na <= optimal);
+  *pna = na;
+  return optimal;
+}
+
+
+static int countint (lua_Integer key, unsigned int *nums) {
+  unsigned int k = arrayindex(key);
+  if (k != 0) {  /* is 'key' an appropriate array index? */
+    nums[luaO_ceillog2(k)]++;  /* count as such */
+    return 1;
+  }
+  else
+    return 0;
+}
+
+
+/*
+** Count keys in array part of table 't': Fill 'nums[i]' with
+** number of keys that will go into corresponding slice and return
+** total number of non-nil keys.
+*/
+static unsigned int numusearray (const Table *t, unsigned int *nums) {
+  int lg;
+  unsigned int ttlg;  /* 2^lg */
+  unsigned int ause = 0;  /* summation of 'nums' */
+  unsigned int i = 1;  /* count to traverse all array keys */
+  unsigned int asize = limitasasize(t);  /* real array size */
+  /* traverse each slice */
+  for (lg = 0, ttlg = 1; lg <= MAXABITS; lg++, ttlg *= 2) {
+    unsigned int lc = 0;  /* counter */
+    unsigned int lim = ttlg;
+    if (lim > asize) {
+      lim = asize;  /* adjust upper limit */
+      if (i > lim)
+        break;  /* no more elements to count */
+    }
+    /* count elements in range (2^(lg - 1), 2^lg] */
+    for (; i <= lim; i++) {
+      if (!isempty(&t->array[i-1]))
+        lc++;
+    }
+    nums[lg] += lc;
+    ause += lc;
+  }
+  return ause;
+}
+
+
+static int numusehash (const Table *t, unsigned int *nums, unsigned int *pna) {
+  int totaluse = 0;  /* total number of elements */
+  int ause = 0;  /* elements added to 'nums' (can go to array part) */
+  int i = sizenode(t);
+  while (i--) {
+    Node *n = &t->node[i];
+    if (!isempty(gval(n))) {
+      if (keyisinteger(n))
+        ause += countint(keyival(n), nums);
+      totaluse++;
+    }
+  }
+  *pna += ause;
+  return totaluse;
+}
+
+
+/*
+** Creates an array for the hash part of a table with the given
+** size, or reuses the dummy node if size is zero.
+** The computation for size overflow is in two steps: the first
+** comparison ensures that the shift in the second one does not
+** overflow.
+*/
+static void setnodevector (lua_State *L, Table *t, unsigned int size) {
+  if (size == 0) {  /* no elements to hash part? */
+    t->node = cast(Node *, dummynode);  /* use common 'dummynode' */
+    t->lsizenode = 0;
+    t->lastfree = NULL;  /* signal that it is using dummy node */
+  }
+  else {
+    int i;
+    int lsize = luaO_ceillog2(size);
+    if (lsize > MAXHBITS || (1u << lsize) > MAXHSIZE)
+      luaG_runerror(L, "table overflow");
+    size = twoto(lsize);
+    t->node = luaM_newvector(L, size, Node);
+    for (i = 0; i < (int)size; i++) {
+      Node *n = gnode(t, i);
+      gnext(n) = 0;
+      setnilkey(n);
+      setempty(gval(n));
+    }
+    t->lsizenode = cast_byte(lsize);
+    t->lastfree = gnode(t, size);  /* all positions are free */
+  }
+}
+
+
+/*
+** (Re)insert all elements from the hash part of 'ot' into table 't'.
+*/
+static void reinsert (lua_State *L, Table *ot, Table *t) {
+  int j;
+  int size = sizenode(ot);
+  for (j = 0; j < size; j++) {
+    Node *old = gnode(ot, j);
+    if (!isempty(gval(old))) {
+      /* doesn't need barrier/invalidate cache, as entry was
+         already present in the table */
+      TValue k;
+      getnodekey(L, &k, old);
+      setobjt2t(L, luaH_set(L, t, &k), gval(old));
+    }
+  }
+}
+
+
+/*
+** Exchange the hash part of 't1' and 't2'.
+*/
+static void exchangehashpart (Table *t1, Table *t2) {
+  lu_byte lsizenode = t1->lsizenode;
+  Node *node = t1->node;
+  Node *lastfree = t1->lastfree;
+  t1->lsizenode = t2->lsizenode;
+  t1->node = t2->node;
+  t1->lastfree = t2->lastfree;
+  t2->lsizenode = lsizenode;
+  t2->node = node;
+  t2->lastfree = lastfree;
+}
+
+
+/*
+** Resize table 't' for the new given sizes. Both allocations (for
+** the hash part and for the array part) can fail, which creates some
+** subtleties. If the first allocation, for the hash part, fails, an
+** error is raised and that is it. Otherwise, it copies the elements from
+** the shrinking part of the array (if it is shrinking) into the new
+** hash. Then it reallocates the array part.  If that fails, the table
+** is in its original state; the function frees the new hash part and then
+** raises the allocation error. Otherwise, it sets the new hash part
+** into the table, initializes the new part of the array (if any) with
+** nils and reinserts the elements of the old hash back into the new
+** parts of the table.
+*/
+void luaH_resize (lua_State *L, Table *t, unsigned int newasize,
+                                          unsigned int nhsize) {
+  unsigned int i;
+  Table newt;  /* to keep the new hash part */
+  unsigned int oldasize = setlimittosize(t);
+  TValue *newarray;
+  /* create new hash part with appropriate size into 'newt' */
+  setnodevector(L, &newt, nhsize);
+  if (newasize < oldasize) {  /* will array shrink? */
+    t->alimit = newasize;  /* pretend array has new size... */
+    exchangehashpart(t, &newt);  /* and new hash */
+    /* re-insert into the new hash the elements from vanishing slice */
+    for (i = newasize; i < oldasize; i++) {
+      if (!isempty(&t->array[i]))
+        luaH_setint(L, t, i + 1, &t->array[i]);
+    }
+    t->alimit = oldasize;  /* restore current size... */
+    exchangehashpart(t, &newt);  /* and hash (in case of errors) */
+  }
+  /* allocate new array */
+  newarray = luaM_reallocvector(L, t->array, oldasize, newasize, TValue);
+  if (unlikely(newarray == NULL && newasize > 0)) {  /* allocation failed? */
+    freehash(L, &newt);  /* release new hash part */
+    luaM_error(L);  /* raise error (with array unchanged) */
+  }
+  /* allocation ok; initialize new part of the array */
+  exchangehashpart(t, &newt);  /* 't' has the new hash ('newt' has the old) */
+  t->array = newarray;  /* set new array part */
+  t->alimit = newasize;
+  for (i = oldasize; i < newasize; i++)  /* clear new slice of the array */
+     setempty(&t->array[i]);
+  /* re-insert elements from old hash part into new parts */
+  reinsert(L, &newt, t);  /* 'newt' now has the old hash */
+  freehash(L, &newt);  /* free old hash part */
+}
+
+
+void luaH_resizearray (lua_State *L, Table *t, unsigned int nasize) {
+  int nsize = allocsizenode(t);
+  luaH_resize(L, t, nasize, nsize);
+}
+
+/*
+** nums[i] = number of keys 'k' where 2^(i - 1) < k <= 2^i
+*/
+static void rehash (lua_State *L, Table *t, const TValue *ek) {
+  unsigned int asize;  /* optimal size for array part */
+  unsigned int na;  /* number of keys in the array part */
+  unsigned int nums[MAXABITS + 1];
+  int i;
+  int totaluse;
+  for (i = 0; i <= MAXABITS; i++) nums[i] = 0;  /* reset counts */
+  setlimittosize(t);
+  na = numusearray(t, nums);  /* count keys in array part */
+  totaluse = na;  /* all those keys are integer keys */
+  totaluse += numusehash(t, nums, &na);  /* count keys in hash part */
+  /* count extra key */
+  if (ttisinteger(ek))
+    na += countint(ivalue(ek), nums);
+  totaluse++;
+  /* compute new size for array part */
+  asize = computesizes(nums, &na);
+  /* resize the table to new computed sizes */
+  luaH_resize(L, t, asize, totaluse - na);
+}
+
+
+
+/*
+** }=============================================================
+*/
+
+
+Table *luaH_new (lua_State *L) {
+  GCObject *o = luaC_newobj(L, LUA_VTABLE, sizeof(Table));
+  Table *t = gco2t(o);
+  t->metatable = NULL;
+  t->flags = cast_byte(~0);
+  t->array = NULL;
+  t->alimit = 0;
+  setnodevector(L, t, 0);
+  return t;
+}
+
+
+void luaH_free (lua_State *L, Table *t) {
+  freehash(L, t);
+  luaM_freearray(L, t->array, luaH_realasize(t));
+  luaM_free(L, t);
+}
+
+
+static Node *getfreepos (Table *t) {
+  if (!isdummy(t)) {
+    while (t->lastfree > t->node) {
+      t->lastfree--;
+      if (keyisnil(t->lastfree))
+        return t->lastfree;
+    }
+  }
+  return NULL;  /* could not find a free place */
+}
+
+
+
+/*
+** inserts a new key into a hash table; first, check whether key's main
+** position is free. If not, check whether colliding node is in its main
+** position or not: if it is not, move colliding node to an empty place and
+** put new key in its main position; otherwise (colliding node is in its main
+** position), new key goes to an empty position.
+*/
+TValue *luaH_newkey (lua_State *L, Table *t, const TValue *key) {
+  Node *mp;
+  TValue aux;
+  if (unlikely(ttisnil(key)))
+    luaG_runerror(L, "table index is nil");
+  else if (ttisfloat(key)) {
+    lua_Number f = fltvalue(key);
+    lua_Integer k;
+    if (luaV_flttointeger(f, &k, F2Ieq)) {  /* does key fit in an integer? */
+      setivalue(&aux, k);
+      key = &aux;  /* insert it as an integer */
+    }
+    else if (unlikely(luai_numisnan(f)))
+      luaG_runerror(L, "table index is NaN");
+  }
+  mp = mainpositionTV(t, key);
+  if (!isempty(gval(mp)) || isdummy(t)) {  /* main position is taken? */
+    Node *othern;
+    Node *f = getfreepos(t);  /* get a free place */
+    if (f == NULL) {  /* cannot find a free place? */
+      rehash(L, t, key);  /* grow table */
+      /* whatever called 'newkey' takes care of TM cache */
+      return luaH_set(L, t, key);  /* insert key into grown table */
+    }
+    lua_assert(!isdummy(t));
+    othern = mainposition(t, keytt(mp), &keyval(mp));
+    if (othern != mp) {  /* is colliding node out of its main position? */
+      /* yes; move colliding node into free position */
+      while (othern + gnext(othern) != mp)  /* find previous */
+        othern += gnext(othern);
+      gnext(othern) = cast_int(f - othern);  /* rechain to point to 'f' */
+      *f = *mp;  /* copy colliding node into free pos. (mp->next also goes) */
+      if (gnext(mp) != 0) {
+        gnext(f) += cast_int(mp - f);  /* correct 'next' */
+        gnext(mp) = 0;  /* now 'mp' is free */
+      }
+      setempty(gval(mp));
+    }
+    else {  /* colliding node is in its own main position */
+      /* new node will go into free position */
+      if (gnext(mp) != 0)
+        gnext(f) = cast_int((mp + gnext(mp)) - f);  /* chain new position */
+      else lua_assert(gnext(f) == 0);
+      gnext(mp) = cast_int(f - mp);
+      mp = f;
+    }
+  }
+  setnodekey(L, mp, key);
+  luaC_barrierback(L, obj2gco(t), key);
+  lua_assert(isempty(gval(mp)));
+  return gval(mp);
+}
+
+
+/*
+** Search function for integers. If integer is inside 'alimit', get it
+** directly from the array part. Otherwise, if 'alimit' is not equal to
+** the real size of the array, key still can be in the array part. In
+** this case, try to avoid a call to 'luaH_realasize' when key is just
+** one more than the limit (so that it can be incremented without
+** changing the real size of the array).
+*/
+const TValue *luaH_getint (Table *t, lua_Integer key) {
+  if (l_castS2U(key) - 1u < t->alimit)  /* 'key' in [1, t->alimit]? */
+    return &t->array[key - 1];
+  else if (!limitequalsasize(t) &&  /* key still may be in the array part? */
+           (l_castS2U(key) == t->alimit + 1 ||
+            l_castS2U(key) - 1u < luaH_realasize(t))) {
+    t->alimit = cast_uint(key);  /* probably '#t' is here now */
+    return &t->array[key - 1];
+  }
+  else {
+    Node *n = hashint(t, key);
+    for (;;) {  /* check whether 'key' is somewhere in the chain */
+      if (keyisinteger(n) && keyival(n) == key)
+        return gval(n);  /* that's it */
+      else {
+        int nx = gnext(n);
+        if (nx == 0) break;
+        n += nx;
+      }
+    }
+    return &absentkey;
+  }
+}
+
+
+/*
+** search function for short strings
+*/
+const TValue *luaH_getshortstr (Table *t, TString *key) {
+  Node *n = hashstr(t, key);
+  lua_assert(key->tt == LUA_VSHRSTR);
+  for (;;) {  /* check whether 'key' is somewhere in the chain */
+    if (keyisshrstr(n) && eqshrstr(keystrval(n), key))
+      return gval(n);  /* that's it */
+    else {
+      int nx = gnext(n);
+      if (nx == 0)
+        return &absentkey;  /* not found */
+      n += nx;
+    }
+  }
+}
+
+
+const TValue *luaH_getstr (Table *t, TString *key) {
+  if (key->tt == LUA_VSHRSTR)
+    return luaH_getshortstr(t, key);
+  else {  /* for long strings, use generic case */
+    TValue ko;
+    setsvalue(cast(lua_State *, NULL), &ko, key);
+    return getgeneric(t, &ko);
+  }
+}
+
+
+/*
+** main search function
+*/
+const TValue *luaH_get (Table *t, const TValue *key) {
+  switch (ttypetag(key)) {
+    case LUA_VSHRSTR: return luaH_getshortstr(t, tsvalue(key));
+    case LUA_VNUMINT: return luaH_getint(t, ivalue(key));
+    case LUA_VNIL: return &absentkey;
+    case LUA_VNUMFLT: {
+      lua_Integer k;
+      if (luaV_flttointeger(fltvalue(key), &k, F2Ieq)) /* integral index? */
+        return luaH_getint(t, k);  /* use specialized version */
+      /* else... */
+    }  /* FALLTHROUGH */
+    default:
+      return getgeneric(t, key);
+  }
+}
+
+
+/*
+** beware: when using this function you probably need to check a GC
+** barrier and invalidate the TM cache.
+*/
+TValue *luaH_set (lua_State *L, Table *t, const TValue *key) {
+  const TValue *p = luaH_get(t, key);
+  if (!isabstkey(p))
+    return cast(TValue *, p);
+  else return luaH_newkey(L, t, key);
+}
+
+
+void luaH_setint (lua_State *L, Table *t, lua_Integer key, TValue *value) {
+  const TValue *p = luaH_getint(t, key);
+  TValue *cell;
+  if (!isabstkey(p))
+    cell = cast(TValue *, p);
+  else {
+    TValue k;
+    setivalue(&k, key);
+    cell = luaH_newkey(L, t, &k);
+  }
+  setobj2t(L, cell, value);
+}
+
+
+/*
+** Try to find a boundary in the hash part of table 't'. From the
+** caller, we know that 'j' is zero or present and that 'j + 1' is
+** present. We want to find a larger key that is absent from the
+** table, so that we can do a binary search between the two keys to
+** find a boundary. We keep doubling 'j' until we get an absent index.
+** If the doubling would overflow, we try LUA_MAXINTEGER. If it is
+** absent, we are ready for the binary search. ('j', being max integer,
+** is larger or equal to 'i', but it cannot be equal because it is
+** absent while 'i' is present; so 'j > i'.) Otherwise, 'j' is a
+** boundary. ('j + 1' cannot be a present integer key because it is
+** not a valid integer in Lua.)
+*/
+static lua_Unsigned hash_search (Table *t, lua_Unsigned j) {
+  lua_Unsigned i;
+  if (j == 0) j++;  /* the caller ensures 'j + 1' is present */
+  do {
+    i = j;  /* 'i' is a present index */
+    if (j <= l_castS2U(LUA_MAXINTEGER) / 2)
+      j *= 2;
+    else {
+      j = LUA_MAXINTEGER;
+      if (isempty(luaH_getint(t, j)))  /* t[j] not present? */
+        break;  /* 'j' now is an absent index */
+      else  /* weird case */
+        return j;  /* well, max integer is a boundary... */
+    }
+  } while (!isempty(luaH_getint(t, j)));  /* repeat until an absent t[j] */
+  /* i < j  &&  t[i] present  &&  t[j] absent */
+  while (j - i > 1u) {  /* do a binary search between them */
+    lua_Unsigned m = (i + j) / 2;
+    if (isempty(luaH_getint(t, m))) j = m;
+    else i = m;
+  }
+  return i;
+}
+
+
+static unsigned int binsearch (const TValue *array, unsigned int i,
+                                                    unsigned int j) {
+  while (j - i > 1u) {  /* binary search */
+    unsigned int m = (i + j) / 2;
+    if (isempty(&array[m - 1])) j = m;
+    else i = m;
+  }
+  return i;
+}
+
+
+/*
+** Try to find a boundary in table 't'. (A 'boundary' is an integer index
+** such that t[i] is present and t[i+1] is absent, or 0 if t[1] is absent
+** and 'maxinteger' if t[maxinteger] is present.)
+** (In the next explanation, we use Lua indices, that is, with base 1.
+** The code itself uses base 0 when indexing the array part of the table.)
+** The code starts with 'limit = t->alimit', a position in the array
+** part that may be a boundary.
+**
+** (1) If 't[limit]' is empty, there must be a boundary before it.
+** As a common case (e.g., after 't[#t]=nil'), check whether 'limit-1'
+** is present. If so, it is a boundary. Otherwise, do a binary search
+** between 0 and limit to find a boundary. In both cases, try to
+** use this boundary as the new 'alimit', as a hint for the next call.
+**
+** (2) If 't[limit]' is not empty and the array has more elements
+** after 'limit', try to find a boundary there. Again, try first
+** the special case (which should be quite frequent) where 'limit+1'
+** is empty, so that 'limit' is a boundary. Otherwise, check the
+** last element of the array part. If it is empty, there must be a
+** boundary between the old limit (present) and the last element
+** (absent), which is found with a binary search. (This boundary always
+** can be a new limit.)
+**
+** (3) The last case is when there are no elements in the array part
+** (limit == 0) or its last element (the new limit) is present.
+** In this case, must check the hash part. If there is no hash part
+** or 'limit+1' is absent, 'limit' is a boundary.  Otherwise, call
+** 'hash_search' to find a boundary in the hash part of the table.
+** (In those cases, the boundary is not inside the array part, and
+** therefore cannot be used as a new limit.)
+*/
+lua_Unsigned luaH_getn (Table *t) {
+  unsigned int limit = t->alimit;
+  if (limit > 0 && isempty(&t->array[limit - 1])) {  /* (1)? */
+    /* there must be a boundary before 'limit' */
+    if (limit >= 2 && !isempty(&t->array[limit - 2])) {
+      /* 'limit - 1' is a boundary; can it be a new limit? */
+      if (ispow2realasize(t) && !ispow2(limit - 1)) {
+        t->alimit = limit - 1;
+        setnorealasize(t);  /* now 'alimit' is not the real size */
+      }
+      return limit - 1;
+    }
+    else {  /* must search for a boundary in [0, limit] */
+      unsigned int boundary = binsearch(t->array, 0, limit);
+      /* can this boundary represent the real size of the array? */
+      if (ispow2realasize(t) && boundary > luaH_realasize(t) / 2) {
+        t->alimit = boundary;  /* use it as the new limit */
+        setnorealasize(t);
+      }
+      return boundary;
+    }
+  }
+  /* 'limit' is zero or present in table */
+  if (!limitequalsasize(t)) {  /* (2)? */
+    /* 'limit' > 0 and array has more elements after 'limit' */
+    if (isempty(&t->array[limit]))  /* 'limit + 1' is empty? */
+      return limit;  /* this is the boundary */
+    /* else, try last element in the array */
+    limit = luaH_realasize(t);
+    if (isempty(&t->array[limit - 1])) {  /* empty? */
+      /* there must be a boundary in the array after old limit,
+         and it must be a valid new limit */
+      unsigned int boundary = binsearch(t->array, t->alimit, limit);
+      t->alimit = boundary;
+      return boundary;
+    }
+    /* else, new limit is present in the table; check the hash part */
+  }
+  /* (3) 'limit' is the last element and either is zero or present in table */
+  lua_assert(limit == luaH_realasize(t) &&
+             (limit == 0 || !isempty(&t->array[limit - 1])));
+  if (isdummy(t) || isempty(luaH_getint(t, cast(lua_Integer, limit + 1))))
+    return limit;  /* 'limit + 1' is absent */
+  else  /* 'limit + 1' is also present */
+    return hash_search(t, limit);
+}
+
+
+
+#if defined(LUA_DEBUG)
+
+/* export these functions for the test library */
+
+Node *luaH_mainposition (const Table *t, const TValue *key) {
+  return mainpositionTV(t, key);
+}
+
+int luaH_isdummy (const Table *t) { return isdummy(t); }
+
+#endif
diff --git a/test/external/lua-5.4.0/src/ltable.h b/test/external/lua-5.4.0/src/ltable.h
new file mode 100644
index 0000000..ebd7f8e
--- /dev/null
+++ b/test/external/lua-5.4.0/src/ltable.h
@@ -0,0 +1,57 @@
+/*
+** $Id: ltable.h $
+** Lua tables (hash)
+** See Copyright Notice in lua.h
+*/
+
+#ifndef ltable_h
+#define ltable_h
+
+#include "lobject.h"
+
+
+#define gnode(t,i)	(&(t)->node[i])
+#define gval(n)		(&(n)->i_val)
+#define gnext(n)	((n)->u.next)
+
+
+#define invalidateTMcache(t)	((t)->flags = 0)
+
+
+/* true when 't' is using 'dummynode' as its hash part */
+#define isdummy(t)		((t)->lastfree == NULL)
+
+
+/* allocated size for hash nodes */
+#define allocsizenode(t)	(isdummy(t) ? 0 : sizenode(t))
+
+
+/* returns the Node, given the value of a table entry */
+#define nodefromval(v)	cast(Node *, (v))
+
+
+LUAI_FUNC const TValue *luaH_getint (Table *t, lua_Integer key);
+LUAI_FUNC void luaH_setint (lua_State *L, Table *t, lua_Integer key,
+                                                    TValue *value);
+LUAI_FUNC const TValue *luaH_getshortstr (Table *t, TString *key);
+LUAI_FUNC const TValue *luaH_getstr (Table *t, TString *key);
+LUAI_FUNC const TValue *luaH_get (Table *t, const TValue *key);
+LUAI_FUNC TValue *luaH_newkey (lua_State *L, Table *t, const TValue *key);
+LUAI_FUNC TValue *luaH_set (lua_State *L, Table *t, const TValue *key);
+LUAI_FUNC Table *luaH_new (lua_State *L);
+LUAI_FUNC void luaH_resize (lua_State *L, Table *t, unsigned int nasize,
+                                                    unsigned int nhsize);
+LUAI_FUNC void luaH_resizearray (lua_State *L, Table *t, unsigned int nasize);
+LUAI_FUNC void luaH_free (lua_State *L, Table *t);
+LUAI_FUNC int luaH_next (lua_State *L, Table *t, StkId key);
+LUAI_FUNC lua_Unsigned luaH_getn (Table *t);
+LUAI_FUNC unsigned int luaH_realasize (const Table *t);
+
+
+#if defined(LUA_DEBUG)
+LUAI_FUNC Node *luaH_mainposition (const Table *t, const TValue *key);
+LUAI_FUNC int luaH_isdummy (const Table *t);
+#endif
+
+
+#endif
diff --git a/test/external/lua-5.4.0/src/ltablib.c b/test/external/lua-5.4.0/src/ltablib.c
new file mode 100644
index 0000000..d344a47
--- /dev/null
+++ b/test/external/lua-5.4.0/src/ltablib.c
@@ -0,0 +1,428 @@
+/*
+** $Id: ltablib.c $
+** Library for Table Manipulation
+** See Copyright Notice in lua.h
+*/
+
+#define ltablib_c
+#define LUA_LIB
+
+#include "lprefix.h"
+
+
+#include <limits.h>
+#include <stddef.h>
+#include <string.h>
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+/*
+** Operations that an object must define to mimic a table
+** (some functions only need some of them)
+*/
+#define TAB_R	1			/* read */
+#define TAB_W	2			/* write */
+#define TAB_L	4			/* length */
+#define TAB_RW	(TAB_R | TAB_W)		/* read/write */
+
+
+#define aux_getn(L,n,w)	(checktab(L, n, (w) | TAB_L), luaL_len(L, n))
+
+
+static int checkfield (lua_State *L, const char *key, int n) {
+  lua_pushstring(L, key);
+  return (lua_rawget(L, -n) != LUA_TNIL);
+}
+
+
+/*
+** Check that 'arg' either is a table or can behave like one (that is,
+** has a metatable with the required metamethods)
+*/
+static void checktab (lua_State *L, int arg, int what) {
+  if (lua_type(L, arg) != LUA_TTABLE) {  /* is it not a table? */
+    int n = 1;  /* number of elements to pop */
+    if (lua_getmetatable(L, arg) &&  /* must have metatable */
+        (!(what & TAB_R) || checkfield(L, "__index", ++n)) &&
+        (!(what & TAB_W) || checkfield(L, "__newindex", ++n)) &&
+        (!(what & TAB_L) || checkfield(L, "__len", ++n))) {
+      lua_pop(L, n);  /* pop metatable and tested metamethods */
+    }
+    else
+      luaL_checktype(L, arg, LUA_TTABLE);  /* force an error */
+  }
+}
+
+
+static int tinsert (lua_State *L) {
+  lua_Integer e = aux_getn(L, 1, TAB_RW) + 1;  /* first empty element */
+  lua_Integer pos;  /* where to insert new element */
+  switch (lua_gettop(L)) {
+    case 2: {  /* called with only 2 arguments */
+      pos = e;  /* insert new element at the end */
+      break;
+    }
+    case 3: {
+      lua_Integer i;
+      pos = luaL_checkinteger(L, 2);  /* 2nd argument is the position */
+      /* check whether 'pos' is in [1, e] */
+      luaL_argcheck(L, (lua_Unsigned)pos - 1u < (lua_Unsigned)e, 2,
+                       "position out of bounds");
+      for (i = e; i > pos; i--) {  /* move up elements */
+        lua_geti(L, 1, i - 1);
+        lua_seti(L, 1, i);  /* t[i] = t[i - 1] */
+      }
+      break;
+    }
+    default: {
+      return luaL_error(L, "wrong number of arguments to 'insert'");
+    }
+  }
+  lua_seti(L, 1, pos);  /* t[pos] = v */
+  return 0;
+}
+
+
+static int tremove (lua_State *L) {
+  lua_Integer size = aux_getn(L, 1, TAB_RW);
+  lua_Integer pos = luaL_optinteger(L, 2, size);
+  if (pos != size)  /* validate 'pos' if given */
+    /* check whether 'pos' is in [1, size + 1] */
+    luaL_argcheck(L, (lua_Unsigned)pos - 1u <= (lua_Unsigned)size, 1,
+                     "position out of bounds");
+  lua_geti(L, 1, pos);  /* result = t[pos] */
+  for ( ; pos < size; pos++) {
+    lua_geti(L, 1, pos + 1);
+    lua_seti(L, 1, pos);  /* t[pos] = t[pos + 1] */
+  }
+  lua_pushnil(L);
+  lua_seti(L, 1, pos);  /* remove entry t[pos] */
+  return 1;
+}
+
+
+/*
+** Copy elements (1[f], ..., 1[e]) into (tt[t], tt[t+1], ...). Whenever
+** possible, copy in increasing order, which is better for rehashing.
+** "possible" means destination after original range, or smaller
+** than origin, or copying to another table.
+*/
+static int tmove (lua_State *L) {
+  lua_Integer f = luaL_checkinteger(L, 2);
+  lua_Integer e = luaL_checkinteger(L, 3);
+  lua_Integer t = luaL_checkinteger(L, 4);
+  int tt = !lua_isnoneornil(L, 5) ? 5 : 1;  /* destination table */
+  checktab(L, 1, TAB_R);
+  checktab(L, tt, TAB_W);
+  if (e >= f) {  /* otherwise, nothing to move */
+    lua_Integer n, i;
+    luaL_argcheck(L, f > 0 || e < LUA_MAXINTEGER + f, 3,
+                  "too many elements to move");
+    n = e - f + 1;  /* number of elements to move */
+    luaL_argcheck(L, t <= LUA_MAXINTEGER - n + 1, 4,
+                  "destination wrap around");
+    if (t > e || t <= f || (tt != 1 && !lua_compare(L, 1, tt, LUA_OPEQ))) {
+      for (i = 0; i < n; i++) {
+        lua_geti(L, 1, f + i);
+        lua_seti(L, tt, t + i);
+      }
+    }
+    else {
+      for (i = n - 1; i >= 0; i--) {
+        lua_geti(L, 1, f + i);
+        lua_seti(L, tt, t + i);
+      }
+    }
+  }
+  lua_pushvalue(L, tt);  /* return destination table */
+  return 1;
+}
+
+
+static void addfield (lua_State *L, luaL_Buffer *b, lua_Integer i) {
+  lua_geti(L, 1, i);
+  if (!lua_isstring(L, -1))
+    luaL_error(L, "invalid value (%s) at index %d in table for 'concat'",
+                  luaL_typename(L, -1), i);
+  luaL_addvalue(b);
+}
+
+
+static int tconcat (lua_State *L) {
+  luaL_Buffer b;
+  lua_Integer last = aux_getn(L, 1, TAB_R);
+  size_t lsep;
+  const char *sep = luaL_optlstring(L, 2, "", &lsep);
+  lua_Integer i = luaL_optinteger(L, 3, 1);
+  last = luaL_optinteger(L, 4, last);
+  luaL_buffinit(L, &b);
+  for (; i < last; i++) {
+    addfield(L, &b, i);
+    luaL_addlstring(&b, sep, lsep);
+  }
+  if (i == last)  /* add last value (if interval was not empty) */
+    addfield(L, &b, i);
+  luaL_pushresult(&b);
+  return 1;
+}
+
+
+/*
+** {======================================================
+** Pack/unpack
+** =======================================================
+*/
+
+static int tpack (lua_State *L) {
+  int i;
+  int n = lua_gettop(L);  /* number of elements to pack */
+  lua_createtable(L, n, 1);  /* create result table */
+  lua_insert(L, 1);  /* put it at index 1 */
+  for (i = n; i >= 1; i--)  /* assign elements */
+    lua_seti(L, 1, i);
+  lua_pushinteger(L, n);
+  lua_setfield(L, 1, "n");  /* t.n = number of elements */
+  return 1;  /* return table */
+}
+
+
+static int tunpack (lua_State *L) {
+  lua_Unsigned n;
+  lua_Integer i = luaL_optinteger(L, 2, 1);
+  lua_Integer e = luaL_opt(L, luaL_checkinteger, 3, luaL_len(L, 1));
+  if (i > e) return 0;  /* empty range */
+  n = (lua_Unsigned)e - i;  /* number of elements minus 1 (avoid overflows) */
+  if (n >= (unsigned int)INT_MAX  || !lua_checkstack(L, (int)(++n)))
+    return luaL_error(L, "too many results to unpack");
+  for (; i < e; i++) {  /* push arg[i..e - 1] (to avoid overflows) */
+    lua_geti(L, 1, i);
+  }
+  lua_geti(L, 1, e);  /* push last element */
+  return (int)n;
+}
+
+/* }====================================================== */
+
+
+
+/*
+** {======================================================
+** Quicksort
+** (based on 'Algorithms in MODULA-3', Robert Sedgewick;
+**  Addison-Wesley, 1993.)
+** =======================================================
+*/
+
+
+/* type for array indices */
+typedef unsigned int IdxT;
+
+
+/*
+** Produce a "random" 'unsigned int' to randomize pivot choice. This
+** macro is used only when 'sort' detects a big imbalance in the result
+** of a partition. (If you don't want/need this "randomness", ~0 is a
+** good choice.)
+*/
+#if !defined(l_randomizePivot)		/* { */
+
+#include <time.h>
+
+/* size of 'e' measured in number of 'unsigned int's */
+#define sof(e)		(sizeof(e) / sizeof(unsigned int))
+
+/*
+** Use 'time' and 'clock' as sources of "randomness". Because we don't
+** know the types 'clock_t' and 'time_t', we cannot cast them to
+** anything without risking overflows. A safe way to use their values
+** is to copy them to an array of a known type and use the array values.
+*/
+static unsigned int l_randomizePivot (void) {
+  clock_t c = clock();
+  time_t t = time(NULL);
+  unsigned int buff[sof(c) + sof(t)];
+  unsigned int i, rnd = 0;
+  memcpy(buff, &c, sof(c) * sizeof(unsigned int));
+  memcpy(buff + sof(c), &t, sof(t) * sizeof(unsigned int));
+  for (i = 0; i < sof(buff); i++)
+    rnd += buff[i];
+  return rnd;
+}
+
+#endif					/* } */
+
+
+/* arrays larger than 'RANLIMIT' may use randomized pivots */
+#define RANLIMIT	100u
+
+
+static void set2 (lua_State *L, IdxT i, IdxT j) {
+  lua_seti(L, 1, i);
+  lua_seti(L, 1, j);
+}
+
+
+/*
+** Return true iff value at stack index 'a' is less than the value at
+** index 'b' (according to the order of the sort).
+*/
+static int sort_comp (lua_State *L, int a, int b) {
+  if (lua_isnil(L, 2))  /* no function? */
+    return lua_compare(L, a, b, LUA_OPLT);  /* a < b */
+  else {  /* function */
+    int res;
+    lua_pushvalue(L, 2);    /* push function */
+    lua_pushvalue(L, a-1);  /* -1 to compensate function */
+    lua_pushvalue(L, b-2);  /* -2 to compensate function and 'a' */
+    lua_call(L, 2, 1);      /* call function */
+    res = lua_toboolean(L, -1);  /* get result */
+    lua_pop(L, 1);          /* pop result */
+    return res;
+  }
+}
+
+
+/*
+** Does the partition: Pivot P is at the top of the stack.
+** precondition: a[lo] <= P == a[up-1] <= a[up],
+** so it only needs to do the partition from lo + 1 to up - 2.
+** Pos-condition: a[lo .. i - 1] <= a[i] == P <= a[i + 1 .. up]
+** returns 'i'.
+*/
+static IdxT partition (lua_State *L, IdxT lo, IdxT up) {
+  IdxT i = lo;  /* will be incremented before first use */
+  IdxT j = up - 1;  /* will be decremented before first use */
+  /* loop invariant: a[lo .. i] <= P <= a[j .. up] */
+  for (;;) {
+    /* next loop: repeat ++i while a[i] < P */
+    while ((void)lua_geti(L, 1, ++i), sort_comp(L, -1, -2)) {
+      if (i == up - 1)  /* a[i] < P  but a[up - 1] == P  ?? */
+        luaL_error(L, "invalid order function for sorting");
+      lua_pop(L, 1);  /* remove a[i] */
+    }
+    /* after the loop, a[i] >= P and a[lo .. i - 1] < P */
+    /* next loop: repeat --j while P < a[j] */
+    while ((void)lua_geti(L, 1, --j), sort_comp(L, -3, -1)) {
+      if (j < i)  /* j < i  but  a[j] > P ?? */
+        luaL_error(L, "invalid order function for sorting");
+      lua_pop(L, 1);  /* remove a[j] */
+    }
+    /* after the loop, a[j] <= P and a[j + 1 .. up] >= P */
+    if (j < i) {  /* no elements out of place? */
+      /* a[lo .. i - 1] <= P <= a[j + 1 .. i .. up] */
+      lua_pop(L, 1);  /* pop a[j] */
+      /* swap pivot (a[up - 1]) with a[i] to satisfy pos-condition */
+      set2(L, up - 1, i);
+      return i;
+    }
+    /* otherwise, swap a[i] - a[j] to restore invariant and repeat */
+    set2(L, i, j);
+  }
+}
+
+
+/*
+** Choose an element in the middle (2nd-3th quarters) of [lo,up]
+** "randomized" by 'rnd'
+*/
+static IdxT choosePivot (IdxT lo, IdxT up, unsigned int rnd) {
+  IdxT r4 = (up - lo) / 4;  /* range/4 */
+  IdxT p = rnd % (r4 * 2) + (lo + r4);
+  lua_assert(lo + r4 <= p && p <= up - r4);
+  return p;
+}
+
+
+/*
+** Quicksort algorithm (recursive function)
+*/
+static void auxsort (lua_State *L, IdxT lo, IdxT up,
+                                   unsigned int rnd) {
+  while (lo < up) {  /* loop for tail recursion */
+    IdxT p;  /* Pivot index */
+    IdxT n;  /* to be used later */
+    /* sort elements 'lo', 'p', and 'up' */
+    lua_geti(L, 1, lo);
+    lua_geti(L, 1, up);
+    if (sort_comp(L, -1, -2))  /* a[up] < a[lo]? */
+      set2(L, lo, up);  /* swap a[lo] - a[up] */
+    else
+      lua_pop(L, 2);  /* remove both values */
+    if (up - lo == 1)  /* only 2 elements? */
+      return;  /* already sorted */
+    if (up - lo < RANLIMIT || rnd == 0)  /* small interval or no randomize? */
+      p = (lo + up)/2;  /* middle element is a good pivot */
+    else  /* for larger intervals, it is worth a random pivot */
+      p = choosePivot(lo, up, rnd);
+    lua_geti(L, 1, p);
+    lua_geti(L, 1, lo);
+    if (sort_comp(L, -2, -1))  /* a[p] < a[lo]? */
+      set2(L, p, lo);  /* swap a[p] - a[lo] */
+    else {
+      lua_pop(L, 1);  /* remove a[lo] */
+      lua_geti(L, 1, up);
+      if (sort_comp(L, -1, -2))  /* a[up] < a[p]? */
+        set2(L, p, up);  /* swap a[up] - a[p] */
+      else
+        lua_pop(L, 2);
+    }
+    if (up - lo == 2)  /* only 3 elements? */
+      return;  /* already sorted */
+    lua_geti(L, 1, p);  /* get middle element (Pivot) */
+    lua_pushvalue(L, -1);  /* push Pivot */
+    lua_geti(L, 1, up - 1);  /* push a[up - 1] */
+    set2(L, p, up - 1);  /* swap Pivot (a[p]) with a[up - 1] */
+    p = partition(L, lo, up);
+    /* a[lo .. p - 1] <= a[p] == P <= a[p + 1 .. up] */
+    if (p - lo < up - p) {  /* lower interval is smaller? */
+      auxsort(L, lo, p - 1, rnd);  /* call recursively for lower interval */
+      n = p - lo;  /* size of smaller interval */
+      lo = p + 1;  /* tail call for [p + 1 .. up] (upper interval) */
+    }
+    else {
+      auxsort(L, p + 1, up, rnd);  /* call recursively for upper interval */
+      n = up - p;  /* size of smaller interval */
+      up = p - 1;  /* tail call for [lo .. p - 1]  (lower interval) */
+    }
+    if ((up - lo) / 128 > n) /* partition too imbalanced? */
+      rnd = l_randomizePivot();  /* try a new randomization */
+  }  /* tail call auxsort(L, lo, up, rnd) */
+}
+
+
+static int sort (lua_State *L) {
+  lua_Integer n = aux_getn(L, 1, TAB_RW);
+  if (n > 1) {  /* non-trivial interval? */
+    luaL_argcheck(L, n < INT_MAX, 1, "array too big");
+    if (!lua_isnoneornil(L, 2))  /* is there a 2nd argument? */
+      luaL_checktype(L, 2, LUA_TFUNCTION);  /* must be a function */
+    lua_settop(L, 2);  /* make sure there are two arguments */
+    auxsort(L, 1, (IdxT)n, 0);
+  }
+  return 0;
+}
+
+/* }====================================================== */
+
+
+static const luaL_Reg tab_funcs[] = {
+  {"concat", tconcat},
+  {"insert", tinsert},
+  {"pack", tpack},
+  {"unpack", tunpack},
+  {"remove", tremove},
+  {"move", tmove},
+  {"sort", sort},
+  {NULL, NULL}
+};
+
+
+LUAMOD_API int luaopen_table (lua_State *L) {
+  luaL_newlib(L, tab_funcs);
+  return 1;
+}
+
diff --git a/test/external/lua-5.4.0/src/ltm.c b/test/external/lua-5.4.0/src/ltm.c
new file mode 100644
index 0000000..ae60983
--- /dev/null
+++ b/test/external/lua-5.4.0/src/ltm.c
@@ -0,0 +1,270 @@
+/*
+** $Id: ltm.c $
+** Tag methods
+** See Copyright Notice in lua.h
+*/
+
+#define ltm_c
+#define LUA_CORE
+
+#include "lprefix.h"
+
+
+#include <string.h>
+
+#include "lua.h"
+
+#include "ldebug.h"
+#include "ldo.h"
+#include "lgc.h"
+#include "lobject.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "ltm.h"
+#include "lvm.h"
+
+
+static const char udatatypename[] = "userdata";
+
+LUAI_DDEF const char *const luaT_typenames_[LUA_TOTALTYPES] = {
+  "no value",
+  "nil", "boolean", udatatypename, "number",
+  "string", "table", "function", udatatypename, "thread",
+  "upvalue", "proto" /* these last cases are used for tests only */
+};
+
+
+void luaT_init (lua_State *L) {
+  static const char *const luaT_eventname[] = {  /* ORDER TM */
+    "__index", "__newindex",
+    "__gc", "__mode", "__len", "__eq",
+    "__add", "__sub", "__mul", "__mod", "__pow",
+    "__div", "__idiv",
+    "__band", "__bor", "__bxor", "__shl", "__shr",
+    "__unm", "__bnot", "__lt", "__le",
+    "__concat", "__call", "__close"
+  };
+  int i;
+  for (i=0; i<TM_N; i++) {
+    G(L)->tmname[i] = luaS_new(L, luaT_eventname[i]);
+    luaC_fix(L, obj2gco(G(L)->tmname[i]));  /* never collect these names */
+  }
+}
+
+
+/*
+** function to be used with macro "fasttm": optimized for absence of
+** tag methods
+*/
+const TValue *luaT_gettm (Table *events, TMS event, TString *ename) {
+  const TValue *tm = luaH_getshortstr(events, ename);
+  lua_assert(event <= TM_EQ);
+  if (notm(tm)) {  /* no tag method? */
+    events->flags |= cast_byte(1u<<event);  /* cache this fact */
+    return NULL;
+  }
+  else return tm;
+}
+
+
+const TValue *luaT_gettmbyobj (lua_State *L, const TValue *o, TMS event) {
+  Table *mt;
+  switch (ttype(o)) {
+    case LUA_TTABLE:
+      mt = hvalue(o)->metatable;
+      break;
+    case LUA_TUSERDATA:
+      mt = uvalue(o)->metatable;
+      break;
+    default:
+      mt = G(L)->mt[ttype(o)];
+  }
+  return (mt ? luaH_getshortstr(mt, G(L)->tmname[event]) : &G(L)->nilvalue);
+}
+
+
+/*
+** Return the name of the type of an object. For tables and userdata
+** with metatable, use their '__name' metafield, if present.
+*/
+const char *luaT_objtypename (lua_State *L, const TValue *o) {
+  Table *mt;
+  if ((ttistable(o) && (mt = hvalue(o)->metatable) != NULL) ||
+      (ttisfulluserdata(o) && (mt = uvalue(o)->metatable) != NULL)) {
+    const TValue *name = luaH_getshortstr(mt, luaS_new(L, "__name"));
+    if (ttisstring(name))  /* is '__name' a string? */
+      return getstr(tsvalue(name));  /* use it as type name */
+  }
+  return ttypename(ttype(o));  /* else use standard type name */
+}
+
+
+void luaT_callTM (lua_State *L, const TValue *f, const TValue *p1,
+                  const TValue *p2, const TValue *p3) {
+  StkId func = L->top;
+  setobj2s(L, func, f);  /* push function (assume EXTRA_STACK) */
+  setobj2s(L, func + 1, p1);  /* 1st argument */
+  setobj2s(L, func + 2, p2);  /* 2nd argument */
+  setobj2s(L, func + 3, p3);  /* 3rd argument */
+  L->top = func + 4;
+  /* metamethod may yield only when called from Lua code */
+  if (isLuacode(L->ci))
+    luaD_call(L, func, 0);
+  else
+    luaD_callnoyield(L, func, 0);
+}
+
+
+void luaT_callTMres (lua_State *L, const TValue *f, const TValue *p1,
+                     const TValue *p2, StkId res) {
+  ptrdiff_t result = savestack(L, res);
+  StkId func = L->top;
+  setobj2s(L, func, f);  /* push function (assume EXTRA_STACK) */
+  setobj2s(L, func + 1, p1);  /* 1st argument */
+  setobj2s(L, func + 2, p2);  /* 2nd argument */
+  L->top += 3;
+  /* metamethod may yield only when called from Lua code */
+  if (isLuacode(L->ci))
+    luaD_call(L, func, 1);
+  else
+    luaD_callnoyield(L, func, 1);
+  res = restorestack(L, result);
+  setobjs2s(L, res, --L->top);  /* move result to its place */
+}
+
+
+static int callbinTM (lua_State *L, const TValue *p1, const TValue *p2,
+                      StkId res, TMS event) {
+  const TValue *tm = luaT_gettmbyobj(L, p1, event);  /* try first operand */
+  if (notm(tm))
+    tm = luaT_gettmbyobj(L, p2, event);  /* try second operand */
+  if (notm(tm)) return 0;
+  luaT_callTMres(L, tm, p1, p2, res);
+  return 1;
+}
+
+
+void luaT_trybinTM (lua_State *L, const TValue *p1, const TValue *p2,
+                    StkId res, TMS event) {
+  if (!callbinTM(L, p1, p2, res, event)) {
+    switch (event) {
+      case TM_BAND: case TM_BOR: case TM_BXOR:
+      case TM_SHL: case TM_SHR: case TM_BNOT: {
+        if (ttisnumber(p1) && ttisnumber(p2))
+          luaG_tointerror(L, p1, p2);
+        else
+          luaG_opinterror(L, p1, p2, "perform bitwise operation on");
+      }
+      /* calls never return, but to avoid warnings: *//* FALLTHROUGH */
+      default:
+        luaG_opinterror(L, p1, p2, "perform arithmetic on");
+    }
+  }
+}
+
+
+void luaT_tryconcatTM (lua_State *L) {
+  StkId top = L->top;
+  if (!callbinTM(L, s2v(top - 2), s2v(top - 1), top - 2, TM_CONCAT))
+    luaG_concaterror(L, s2v(top - 2), s2v(top - 1));
+}
+
+
+void luaT_trybinassocTM (lua_State *L, const TValue *p1, const TValue *p2,
+                                       int flip, StkId res, TMS event) {
+  if (flip)
+    luaT_trybinTM(L, p2, p1, res, event);
+  else
+    luaT_trybinTM(L, p1, p2, res, event);
+}
+
+
+void luaT_trybiniTM (lua_State *L, const TValue *p1, lua_Integer i2,
+                                   int flip, StkId res, TMS event) {
+  TValue aux;
+  setivalue(&aux, i2);
+  luaT_trybinassocTM(L, p1, &aux, flip, res, event);
+}
+
+
+/*
+** Calls an order tag method.
+** For lessequal, LUA_COMPAT_LT_LE keeps compatibility with old
+** behavior: if there is no '__le', try '__lt', based on l <= r iff
+** !(r < l) (assuming a total order). If the metamethod yields during
+** this substitution, the continuation has to know about it (to negate
+** the result of r<l); bit CIST_LEQ in the call status keeps that
+** information.
+*/
+int luaT_callorderTM (lua_State *L, const TValue *p1, const TValue *p2,
+                      TMS event) {
+  if (callbinTM(L, p1, p2, L->top, event))  /* try original event */
+    return !l_isfalse(s2v(L->top));
+#if defined(LUA_COMPAT_LT_LE)
+  else if (event == TM_LE) {
+      /* try '!(p2 < p1)' for '(p1 <= p2)' */
+      L->ci->callstatus |= CIST_LEQ;  /* mark it is doing 'lt' for 'le' */
+      if (callbinTM(L, p2, p1, L->top, TM_LT)) {
+        L->ci->callstatus ^= CIST_LEQ;  /* clear mark */
+        return l_isfalse(s2v(L->top));
+      }
+      /* else error will remove this 'ci'; no need to clear mark */
+  }
+#endif
+  luaG_ordererror(L, p1, p2);  /* no metamethod found */
+  return 0;  /* to avoid warnings */
+}
+
+
+int luaT_callorderiTM (lua_State *L, const TValue *p1, int v2,
+                       int flip, int isfloat, TMS event) {
+  TValue aux; const TValue *p2;
+  if (isfloat) {
+    setfltvalue(&aux, cast_num(v2));
+  }
+  else
+    setivalue(&aux, v2);
+  if (flip) {  /* arguments were exchanged? */
+    p2 = p1; p1 = &aux;  /* correct them */
+  }
+  else
+    p2 = &aux;
+  return luaT_callorderTM(L, p1, p2, event);
+}
+
+
+void luaT_adjustvarargs (lua_State *L, int nfixparams, CallInfo *ci,
+                         const Proto *p) {
+  int i;
+  int actual = cast_int(L->top - ci->func) - 1;  /* number of arguments */
+  int nextra = actual - nfixparams;  /* number of extra arguments */
+  ci->u.l.nextraargs = nextra;
+  checkstackGC(L, p->maxstacksize + 1);
+  /* copy function to the top of the stack */
+  setobjs2s(L, L->top++, ci->func);
+  /* move fixed parameters to the top of the stack */
+  for (i = 1; i <= nfixparams; i++) {
+    setobjs2s(L, L->top++, ci->func + i);
+    setnilvalue(s2v(ci->func + i));  /* erase original parameter (for GC) */
+  }
+  ci->func += actual + 1;
+  ci->top += actual + 1;
+  lua_assert(L->top <= ci->top && ci->top <= L->stack_last);
+}
+
+
+void luaT_getvarargs (lua_State *L, CallInfo *ci, StkId where, int wanted) {
+  int i;
+  int nextra = ci->u.l.nextraargs;
+  if (wanted < 0) {
+    wanted = nextra;  /* get all extra arguments available */
+    checkstackp(L, nextra, where);  /* ensure stack space */
+    L->top = where + nextra;  /* next instruction will need top */
+  }
+  for (i = 0; i < wanted && i < nextra; i++)
+    setobjs2s(L, where + i, ci->func - nextra + i);
+  for (; i < wanted; i++)   /* complete required results with nil */
+    setnilvalue(s2v(where + i));
+}
+
diff --git a/test/external/lua-5.4.0/src/ltm.h b/test/external/lua-5.4.0/src/ltm.h
new file mode 100644
index 0000000..99b545e
--- /dev/null
+++ b/test/external/lua-5.4.0/src/ltm.h
@@ -0,0 +1,94 @@
+/*
+** $Id: ltm.h $
+** Tag methods
+** See Copyright Notice in lua.h
+*/
+
+#ifndef ltm_h
+#define ltm_h
+
+
+#include "lobject.h"
+
+
+/*
+* WARNING: if you change the order of this enumeration,
+* grep "ORDER TM" and "ORDER OP"
+*/
+typedef enum {
+  TM_INDEX,
+  TM_NEWINDEX,
+  TM_GC,
+  TM_MODE,
+  TM_LEN,
+  TM_EQ,  /* last tag method with fast access */
+  TM_ADD,
+  TM_SUB,
+  TM_MUL,
+  TM_MOD,
+  TM_POW,
+  TM_DIV,
+  TM_IDIV,
+  TM_BAND,
+  TM_BOR,
+  TM_BXOR,
+  TM_SHL,
+  TM_SHR,
+  TM_UNM,
+  TM_BNOT,
+  TM_LT,
+  TM_LE,
+  TM_CONCAT,
+  TM_CALL,
+  TM_CLOSE,
+  TM_N		/* number of elements in the enum */
+} TMS;
+
+
+/*
+** Test whether there is no tagmethod.
+** (Because tagmethods use raw accesses, the result may be an "empty" nil.)
+*/
+#define notm(tm)	ttisnil(tm)
+
+
+#define gfasttm(g,et,e) ((et) == NULL ? NULL : \
+  ((et)->flags & (1u<<(e))) ? NULL : luaT_gettm(et, e, (g)->tmname[e]))
+
+#define fasttm(l,et,e)	gfasttm(G(l), et, e)
+
+#define ttypename(x)	luaT_typenames_[(x) + 1]
+
+LUAI_DDEC(const char *const luaT_typenames_[LUA_TOTALTYPES];)
+
+
+LUAI_FUNC const char *luaT_objtypename (lua_State *L, const TValue *o);
+
+LUAI_FUNC const TValue *luaT_gettm (Table *events, TMS event, TString *ename);
+LUAI_FUNC const TValue *luaT_gettmbyobj (lua_State *L, const TValue *o,
+                                                       TMS event);
+LUAI_FUNC void luaT_init (lua_State *L);
+
+LUAI_FUNC void luaT_callTM (lua_State *L, const TValue *f, const TValue *p1,
+                            const TValue *p2, const TValue *p3);
+LUAI_FUNC void luaT_callTMres (lua_State *L, const TValue *f,
+                            const TValue *p1, const TValue *p2, StkId p3);
+LUAI_FUNC void luaT_trybinTM (lua_State *L, const TValue *p1, const TValue *p2,
+                              StkId res, TMS event);
+LUAI_FUNC void luaT_tryconcatTM (lua_State *L);
+LUAI_FUNC void luaT_trybinassocTM (lua_State *L, const TValue *p1,
+       const TValue *p2, int inv, StkId res, TMS event);
+LUAI_FUNC void luaT_trybiniTM (lua_State *L, const TValue *p1, lua_Integer i2,
+                               int inv, StkId res, TMS event);
+LUAI_FUNC int luaT_callorderTM (lua_State *L, const TValue *p1,
+                                const TValue *p2, TMS event);
+LUAI_FUNC int luaT_callorderiTM (lua_State *L, const TValue *p1, int v2,
+                                 int inv, int isfloat, TMS event);
+
+LUAI_FUNC void luaT_adjustvarargs (lua_State *L, int nfixparams,
+                                   struct CallInfo *ci, const Proto *p);
+LUAI_FUNC void luaT_getvarargs (lua_State *L, struct CallInfo *ci,
+                                              StkId where, int wanted);
+
+
+#endif
diff --git a/test/external/lua-5.4.0/src/lua.c b/test/external/lua-5.4.0/src/lua.c
new file mode 100644
index 0000000..454ce12
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lua.c
@@ -0,0 +1,635 @@
+/*
+** $Id: lua.c $
+** Lua stand-alone interpreter
+** See Copyright Notice in lua.h
+*/
+
+#define lua_c
+
+#include "lprefix.h"
+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <signal.h>
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+#if !defined(LUA_PROGNAME)
+#define LUA_PROGNAME		"lua"
+#endif
+
+#if !defined(LUA_INIT_VAR)
+#define LUA_INIT_VAR		"LUA_INIT"
+#endif
+
+#define LUA_INITVARVERSION	LUA_INIT_VAR LUA_VERSUFFIX
+
+
+static lua_State *globalL = NULL;
+
+static const char *progname = LUA_PROGNAME;
+
+
+/*
+** Hook set by signal function to stop the interpreter.
+*/
+static void lstop (lua_State *L, lua_Debug *ar) {
+  (void)ar;  /* unused arg. */
+  lua_sethook(L, NULL, 0, 0);  /* reset hook */
+  luaL_error(L, "interrupted!");
+}
+
+
+/*
+** Function to be called at a C signal. Because a C signal cannot
+** just change a Lua state (as there is no proper synchronization),
+** this function only sets a hook that, when called, will stop the
+** interpreter.
+*/
+static void laction (int i) {
+  int flag = LUA_MASKCALL | LUA_MASKRET | LUA_MASKLINE | LUA_MASKCOUNT;
+  signal(i, SIG_DFL); /* if another SIGINT happens, terminate process */
+  lua_sethook(globalL, lstop, flag, 1);
+}
+
+
+static void print_usage (const char *badoption) {
+  lua_writestringerror("%s: ", progname);
+  if (badoption[1] == 'e' || badoption[1] == 'l')
+    lua_writestringerror("'%s' needs argument\n", badoption);
+  else
+    lua_writestringerror("unrecognized option '%s'\n", badoption);
+  lua_writestringerror(
+  "usage: %s [options] [script [args]]\n"
+  "Available options are:\n"
+  "  -e stat  execute string 'stat'\n"
+  "  -i       enter interactive mode after executing 'script'\n"
+  "  -l name  require library 'name' into global 'name'\n"
+  "  -v       show version information\n"
+  "  -E       ignore environment variables\n"
+  "  -W       turn warnings on\n"
+  "  --       stop handling options\n"
+  "  -        stop handling options and execute stdin\n"
+  ,
+  progname);
+}
+
+
+/*
+** Prints an error message, adding the program name in front of it
+** (if present)
+*/
+static void l_message (const char *pname, const char *msg) {
+  if (pname) lua_writestringerror("%s: ", pname);
+  lua_writestringerror("%s\n", msg);
+}
+
+
+/*
+** Check whether 'status' is not OK and, if so, prints the error
+** message on the top of the stack. It assumes that the error object
+** is a string, as it was either generated by Lua or by 'msghandler'.
+*/
+static int report (lua_State *L, int status) {
+  if (status != LUA_OK) {
+    const char *msg = lua_tostring(L, -1);
+    l_message(progname, msg);
+    lua_pop(L, 1);  /* remove message */
+  }
+  return status;
+}
+
+
+/*
+** Message handler used to run all chunks
+*/
+static int msghandler (lua_State *L) {
+  const char *msg = lua_tostring(L, 1);
+  if (msg == NULL) {  /* is error object not a string? */
+    if (luaL_callmeta(L, 1, "__tostring") &&  /* does it have a metamethod */
+        lua_type(L, -1) == LUA_TSTRING)  /* that produces a string? */
+      return 1;  /* that is the message */
+    else
+      msg = lua_pushfstring(L, "(error object is a %s value)",
+                               luaL_typename(L, 1));
+  }
+  luaL_traceback(L, L, msg, 1);  /* append a standard traceback */
+  return 1;  /* return the traceback */
+}
+
+
+/*
+** Interface to 'lua_pcall', which sets appropriate message function
+** and C-signal handler. Used to run all chunks.
+*/
+static int docall (lua_State *L, int narg, int nres) {
+  int status;
+  int base = lua_gettop(L) - narg;  /* function index */
+  lua_pushcfunction(L, msghandler);  /* push message handler */
+  lua_insert(L, base);  /* put it under function and args */
+  globalL = L;  /* to be available to 'laction' */
+  signal(SIGINT, laction);  /* set C-signal handler */
+  status = lua_pcall(L, narg, nres, base);
+  signal(SIGINT, SIG_DFL); /* reset C-signal handler */
+  lua_remove(L, base);  /* remove message handler from the stack */
+  return status;
+}
+
+
+static void print_version (void) {
+  lua_writestring(LUA_COPYRIGHT, strlen(LUA_COPYRIGHT));
+  lua_writeline();
+}
+
+
+/*
+** Create the 'arg' table, which stores all arguments from the
+** command line ('argv'). It should be aligned so that, at index 0,
+** it has 'argv[script]', which is the script name. The arguments
+** to the script (everything after 'script') go to positive indices;
+** other arguments (before the script name) go to negative indices.
+** If there is no script name, assume interpreter's name as base.
+*/
+static void createargtable (lua_State *L, char **argv, int argc, int script) {
+  int i, narg;
+  if (script == argc) script = 0;  /* no script name? */
+  narg = argc - (script + 1);  /* number of positive indices */
+  lua_createtable(L, narg, script + 1);
+  for (i = 0; i < argc; i++) {
+    lua_pushstring(L, argv[i]);
+    lua_rawseti(L, -2, i - script);
+  }
+  lua_setglobal(L, "arg");
+}
+
+
+static int dochunk (lua_State *L, int status) {
+  if (status == LUA_OK) status = docall(L, 0, 0);
+  return report(L, status);
+}
+
+
+static int dofile (lua_State *L, const char *name) {
+  return dochunk(L, luaL_loadfile(L, name));
+}
+
+
+static int dostring (lua_State *L, const char *s, const char *name) {
+  return dochunk(L, luaL_loadbuffer(L, s, strlen(s), name));
+}
+
+
+/*
+** Calls 'require(name)' and stores the result in a global variable
+** with the given name.
+*/
+static int dolibrary (lua_State *L, const char *name) {
+  int status;
+  lua_getglobal(L, "require");
+  lua_pushstring(L, name);
+  status = docall(L, 1, 1);  /* call 'require(name)' */
+  if (status == LUA_OK)
+    lua_setglobal(L, name);  /* global[name] = require return */
+  return report(L, status);
+}
+
+
+/*
+** Push on the stack the contents of table 'arg' from 1 to #arg
+*/
+static int pushargs (lua_State *L) {
+  int i, n;
+  if (lua_getglobal(L, "arg") != LUA_TTABLE)
+    luaL_error(L, "'arg' is not a table");
+  n = (int)luaL_len(L, -1);
+  luaL_checkstack(L, n + 3, "too many arguments to script");
+  for (i = 1; i <= n; i++)
+    lua_rawgeti(L, -i, i);
+  lua_remove(L, -i);  /* remove table from the stack */
+  return n;
+}
+
+
+static int handle_script (lua_State *L, char **argv) {
+  int status;
+  const char *fname = argv[0];
+  if (strcmp(fname, "-") == 0 && strcmp(argv[-1], "--") != 0)
+    fname = NULL;  /* stdin */
+  status = luaL_loadfile(L, fname);
+  if (status == LUA_OK) {
+    int n = pushargs(L);  /* push arguments to script */
+    status = docall(L, n, LUA_MULTRET);
+  }
+  return report(L, status);
+}
+
+
+/* bits of various argument indicators in 'args' */
+#define has_error	1	/* bad option */
+#define has_i		2	/* -i */
+#define has_v		4	/* -v */
+#define has_e		8	/* -e */
+#define has_E		16	/* -E */
+
+
+/*
+** Traverses all arguments from 'argv', returning a mask with those
+** needed before running any Lua code (or an error code if it finds
+** any invalid argument). 'first' returns the first not-handled argument
+** (either the script name or a bad argument in case of error).
+*/
+static int collectargs (char **argv, int *first) {
+  int args = 0;
+  int i;
+  for (i = 1; argv[i] != NULL; i++) {
+    *first = i;
+    if (argv[i][0] != '-')  /* not an option? */
+        return args;  /* stop handling options */
+    switch (argv[i][1]) {  /* else check option */
+      case '-':  /* '--' */
+        if (argv[i][2] != '\0')  /* extra characters after '--'? */
+          return has_error;  /* invalid option */
+        *first = i + 1;
+        return args;
+      case '\0':  /* '-' */
+        return args;  /* script "name" is '-' */
+      case 'E':
+        if (argv[i][2] != '\0')  /* extra characters? */
+          return has_error;  /* invalid option */
+        args |= has_E;
+        break;
+      case 'W':
+        if (argv[i][2] != '\0')  /* extra characters? */
+          return has_error;  /* invalid option */
+        break;
+      case 'i':
+        args |= has_i;  /* (-i implies -v) *//* FALLTHROUGH */
+      case 'v':
+        if (argv[i][2] != '\0')  /* extra characters? */
+          return has_error;  /* invalid option */
+        args |= has_v;
+        break;
+      case 'e':
+        args |= has_e;  /* FALLTHROUGH */
+      case 'l':  /* both options need an argument */
+        if (argv[i][2] == '\0') {  /* no concatenated argument? */
+          i++;  /* try next 'argv' */
+          if (argv[i] == NULL || argv[i][0] == '-')
+            return has_error;  /* no next argument or it is another option */
+        }
+        break;
+      default:  /* invalid option */
+        return has_error;
+    }
+  }
+  *first = i;  /* no script name */
+  return args;
+}
+
+
+/*
+** Processes options 'e' and 'l', which involve running Lua code, and
+** 'W', which also affects the state.
+** Returns 0 if some code raises an error.
+*/
+static int runargs (lua_State *L, char **argv, int n) {
+  int i;
+  for (i = 1; i < n; i++) {
+    int option = argv[i][1];
+    lua_assert(argv[i][0] == '-');  /* already checked */
+    switch (option) {
+      case 'e':  case 'l': {
+        int status;
+        const char *extra = argv[i] + 2;  /* both options need an argument */
+        if (*extra == '\0') extra = argv[++i];
+        lua_assert(extra != NULL);
+        status = (option == 'e')
+                 ? dostring(L, extra, "=(command line)")
+                 : dolibrary(L, extra);
+        if (status != LUA_OK) return 0;
+        break;
+      }
+      case 'W':
+        lua_warning(L, "@on", 0);  /* warnings on */
+        break;
+    }
+  }
+  return 1;
+}
+
+
+static int handle_luainit (lua_State *L) {
+  const char *name = "=" LUA_INITVARVERSION;
+  const char *init = getenv(name + 1);
+  if (init == NULL) {
+    name = "=" LUA_INIT_VAR;
+    init = getenv(name + 1);  /* try alternative name */
+  }
+  if (init == NULL) return LUA_OK;
+  else if (init[0] == '@')
+    return dofile(L, init+1);
+  else
+    return dostring(L, init, name);
+}
+
+
+/*
+** {==================================================================
+** Read-Eval-Print Loop (REPL)
+** ===================================================================
+*/
+
+#if !defined(LUA_PROMPT)
+#define LUA_PROMPT		"> "
+#define LUA_PROMPT2		">> "
+#endif
+
+#if !defined(LUA_MAXINPUT)
+#define LUA_MAXINPUT		512
+#endif
+
+
+/*
+** lua_stdin_is_tty detects whether the standard input is a 'tty' (that
+** is, whether we're running lua interactively).
+*/
+#if !defined(lua_stdin_is_tty)	/* { */
+
+#if defined(LUA_USE_POSIX)	/* { */
+
+#include <unistd.h>
+#define lua_stdin_is_tty()	isatty(0)
+
+#elif defined(LUA_USE_WINDOWS)	/* }{ */
+
+#include <io.h>
+#include <windows.h>
+
+#define lua_stdin_is_tty()	_isatty(_fileno(stdin))
+
+#else				/* }{ */
+
+/* ISO C definition */
+#define lua_stdin_is_tty()	1  /* assume stdin is a tty */
+
+#endif				/* } */
+
+#endif				/* } */
+
+
+/*
+** lua_readline defines how to show a prompt and then read a line from
+** the standard input.
+** lua_saveline defines how to "save" a read line in a "history".
+** lua_freeline defines how to free a line read by lua_readline.
+*/
+#if !defined(lua_readline)	/* { */
+
+#if defined(LUA_USE_READLINE)	/* { */
+
+#include <readline/readline.h>
+#include <readline/history.h>
+#define lua_initreadline(L)	((void)L, rl_readline_name="lua")
+#define lua_readline(L,b,p)	((void)L, ((b)=readline(p)) != NULL)
+#define lua_saveline(L,line)	((void)L, add_history(line))
+#define lua_freeline(L,b)	((void)L, free(b))
+
+#else				/* }{ */
+
+#define lua_initreadline(L)  ((void)L)
+#define lua_readline(L,b,p) \
+        ((void)L, fputs(p, stdout), fflush(stdout),  /* show prompt */ \
+        fgets(b, LUA_MAXINPUT, stdin) != NULL)  /* get line */
+#define lua_saveline(L,line)	{ (void)L; (void)line; }
+#define lua_freeline(L,b)	{ (void)L; (void)b; }
+
+#endif				/* } */
+
+#endif				/* } */
+
+
+/*
+** Returns the string to be used as a prompt by the interpreter.
+*/
+static const char *get_prompt (lua_State *L, int firstline) {
+  const char *p;
+  lua_getglobal(L, firstline ? "_PROMPT" : "_PROMPT2");
+  p = lua_tostring(L, -1);
+  if (p == NULL) p = (firstline ? LUA_PROMPT : LUA_PROMPT2);
+  return p;
+}
+
+/* mark in error messages for incomplete statements */
+#define EOFMARK		"<eof>"
+#define marklen		(sizeof(EOFMARK)/sizeof(char) - 1)
+
+
+/*
+** Check whether 'status' signals a syntax error and the error
+** message at the top of the stack ends with the above mark for
+** incomplete statements.
+*/
+static int incomplete (lua_State *L, int status) {
+  if (status == LUA_ERRSYNTAX) {
+    size_t lmsg;
+    const char *msg = lua_tolstring(L, -1, &lmsg);
+    if (lmsg >= marklen && strcmp(msg + lmsg - marklen, EOFMARK) == 0) {
+      lua_pop(L, 1);
+      return 1;
+    }
+  }
+  return 0;  /* else... */
+}
+
+
+/*
+** Prompt the user, read a line, and push it into the Lua stack.
+*/
+static int pushline (lua_State *L, int firstline) {
+  char buffer[LUA_MAXINPUT];
+  char *b = buffer;
+  size_t l;
+  const char *prmt = get_prompt(L, firstline);
+  int readstatus = lua_readline(L, b, prmt);
+  if (readstatus == 0)
+    return 0;  /* no input (prompt will be popped by caller) */
+  lua_pop(L, 1);  /* remove prompt */
+  l = strlen(b);
+  if (l > 0 && b[l-1] == '\n')  /* line ends with newline? */
+    b[--l] = '\0';  /* remove it */
+  if (firstline && b[0] == '=')  /* for compatibility with 5.2, ... */
+    lua_pushfstring(L, "return %s", b + 1);  /* change '=' to 'return' */
+  else
+    lua_pushlstring(L, b, l);
+  lua_freeline(L, b);
+  return 1;
+}
+
+
+/*
+** Try to compile line on the stack as 'return <line>;'; on return, stack
+** has either compiled chunk or original line (if compilation failed).
+*/
+static int addreturn (lua_State *L) {
+  const char *line = lua_tostring(L, -1);  /* original line */
+  const char *retline = lua_pushfstring(L, "return %s;", line);
+  int status = luaL_loadbuffer(L, retline, strlen(retline), "=stdin");
+  if (status == LUA_OK) {
+    lua_remove(L, -2);  /* remove modified line */
+    if (line[0] != '\0')  /* non empty? */
+      lua_saveline(L, line);  /* keep history */
+  }
+  else
+    lua_pop(L, 2);  /* pop result from 'luaL_loadbuffer' and modified line */
+  return status;
+}
+
+
+/*
+** Read multiple lines until a complete Lua statement
+*/
+static int multiline (lua_State *L) {
+  for (;;) {  /* repeat until gets a complete statement */
+    size_t len;
+    const char *line = lua_tolstring(L, 1, &len);  /* get what it has */
+    int status = luaL_loadbuffer(L, line, len, "=stdin");  /* try it */
+    if (!incomplete(L, status) || !pushline(L, 0)) {
+      lua_saveline(L, line);  /* keep history */
+      return status;  /* cannot or should not try to add continuation line */
+    }
+    lua_pushliteral(L, "\n");  /* add newline... */
+    lua_insert(L, -2);  /* ...between the two lines */
+    lua_concat(L, 3);  /* join them */
+  }
+}
+
+
+/*
+** Read a line and try to load (compile) it first as an expression (by
+** adding "return " in front of it) and second as a statement. Return
+** the final status of load/call with the resulting function (if any)
+** in the top of the stack.
+*/
+static int loadline (lua_State *L) {
+  int status;
+  lua_settop(L, 0);
+  if (!pushline(L, 1))
+    return -1;  /* no input */
+  if ((status = addreturn(L)) != LUA_OK)  /* 'return ...' did not work? */
+    status = multiline(L);  /* try as command, maybe with continuation lines */
+  lua_remove(L, 1);  /* remove line from the stack */
+  lua_assert(lua_gettop(L) == 1);
+  return status;
+}
+
+
+/*
+** Prints (calling the Lua 'print' function) any values on the stack
+*/
+static void l_print (lua_State *L) {
+  int n = lua_gettop(L);
+  if (n > 0) {  /* any result to be printed? */
+    luaL_checkstack(L, LUA_MINSTACK, "too many results to print");
+    lua_getglobal(L, "print");
+    lua_insert(L, 1);
+    if (lua_pcall(L, n, 0, 0) != LUA_OK)
+      l_message(progname, lua_pushfstring(L, "error calling 'print' (%s)",
+                                             lua_tostring(L, -1)));
+  }
+}
+
+
+/*
+** Do the REPL: repeatedly read (load) a line, evaluate (call) it, and
+** print any results.
+*/
+static void doREPL (lua_State *L) {
+  int status;
+  const char *oldprogname = progname;
+  progname = NULL;  /* no 'progname' on errors in interactive mode */
+  lua_initreadline(L);
+  while ((status = loadline(L)) != -1) {
+    if (status == LUA_OK)
+      status = docall(L, 0, LUA_MULTRET);
+    if (status == LUA_OK) l_print(L);
+    else report(L, status);
+  }
+  lua_settop(L, 0);  /* clear stack */
+  lua_writeline();
+  progname = oldprogname;
+}
+
+/* }================================================================== */
+
+
+/*
+** Main body of stand-alone interpreter (to be called in protected mode).
+** Reads the options and handles them all.
+*/
+static int pmain (lua_State *L) {
+  int argc = (int)lua_tointeger(L, 1);
+  char **argv = (char **)lua_touserdata(L, 2);
+  int script;
+  int args = collectargs(argv, &script);
+  luaL_checkversion(L);  /* check that interpreter has correct version */
+  if (argv[0] && argv[0][0]) progname = argv[0];
+  if (args == has_error) {  /* bad arg? */
+    print_usage(argv[script]);  /* 'script' has index of bad arg. */
+    return 0;
+  }
+  if (args & has_v)  /* option '-v'? */
+    print_version();
+  if (args & has_E) {  /* option '-E'? */
+    lua_pushboolean(L, 1);  /* signal for libraries to ignore env. vars. */
+    lua_setfield(L, LUA_REGISTRYINDEX, "LUA_NOENV");
+  }
+  luaL_openlibs(L);  /* open standard libraries */
+  createargtable(L, argv, argc, script);  /* create table 'arg' */
+  lua_gc(L, LUA_GCGEN, 0, 0);  /* GC in generational mode */
+  if (!(args & has_E)) {  /* no option '-E'? */
+    if (handle_luainit(L) != LUA_OK)  /* run LUA_INIT */
+      return 0;  /* error running LUA_INIT */
+  }
+  if (!runargs(L, argv, script))  /* execute arguments -e and -l */
+    return 0;  /* something failed */
+  if (script < argc &&  /* execute main script (if there is one) */
+      handle_script(L, argv + script) != LUA_OK)
+    return 0;
+  if (args & has_i)  /* -i option? */
+    doREPL(L);  /* do read-eval-print loop */
+  else if (script == argc && !(args & (has_e | has_v))) {  /* no arguments? */
+    if (lua_stdin_is_tty()) {  /* running in interactive mode? */
+      print_version();
+      doREPL(L);  /* do read-eval-print loop */
+    }
+    else dofile(L, NULL);  /* executes stdin as a file */
+  }
+  lua_pushboolean(L, 1);  /* signal no errors */
+  return 1;
+}
+
+
+int main (int argc, char **argv) {
+  int status, result;
+  lua_State *L = luaL_newstate();  /* create state */
+  if (L == NULL) {
+    l_message(argv[0], "cannot create state: not enough memory");
+    return EXIT_FAILURE;
+  }
+  lua_pushcfunction(L, &pmain);  /* to call 'pmain' in protected mode */
+  lua_pushinteger(L, argc);  /* 1st argument */
+  lua_pushlightuserdata(L, argv); /* 2nd argument */
+  status = lua_pcall(L, 2, 1, 0);  /* do the call */
+  result = lua_toboolean(L, -1);  /* get result */
+  report(L, status);
+  lua_close(L);
+  return (result && status == LUA_OK) ? EXIT_SUCCESS : EXIT_FAILURE;
+}
+
diff --git a/test/external/lua-5.4.0/src/lua.h b/test/external/lua-5.4.0/src/lua.h
new file mode 100644
index 0000000..b348c14
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lua.h
@@ -0,0 +1,517 @@
+/*
+** $Id: lua.h $
+** Lua - A Scripting Language
+** Lua.org, PUC-Rio, Brazil (http://www.lua.org)
+** See Copyright Notice at the end of this file
+*/
+
+
+#ifndef lua_h
+#define lua_h
+
+#include <stdarg.h>
+#include <stddef.h>
+
+
+#include "luaconf.h"
+
+
+#define LUA_VERSION_MAJOR	"5"
+#define LUA_VERSION_MINOR	"4"
+#define LUA_VERSION_RELEASE	"0"
+
+#define LUA_VERSION_NUM			504
+#define LUA_VERSION_RELEASE_NUM		(LUA_VERSION_NUM * 100 + 0)
+
+#define LUA_VERSION	"Lua " LUA_VERSION_MAJOR "." LUA_VERSION_MINOR
+#define LUA_RELEASE	LUA_VERSION "." LUA_VERSION_RELEASE
+#define LUA_COPYRIGHT	LUA_RELEASE "  Copyright (C) 1994-2020 Lua.org, PUC-Rio"
+#define LUA_AUTHORS	"R. Ierusalimschy, L. H. de Figueiredo, W. Celes"
+
+
+/* mark for precompiled code ('<esc>Lua') */
+#define LUA_SIGNATURE	"\x1bLua"
+
+/* option for multiple returns in 'lua_pcall' and 'lua_call' */
+#define LUA_MULTRET	(-1)
+
+
+/*
+** Pseudo-indices
+** (-LUAI_MAXSTACK is the minimum valid index; we keep some free empty
+** space after that to help overflow detection)
+*/
+#define LUA_REGISTRYINDEX	(-LUAI_MAXSTACK - 1000)
+#define lua_upvalueindex(i)	(LUA_REGISTRYINDEX - (i))
+
+
+/* thread status */
+#define LUA_OK		0
+#define LUA_YIELD	1
+#define LUA_ERRRUN	2
+#define LUA_ERRSYNTAX	3
+#define LUA_ERRMEM	4
+#define LUA_ERRERR	5
+
+
+typedef struct lua_State lua_State;
+
+
+/*
+** basic types
+*/
+#define LUA_TNONE		(-1)
+
+#define LUA_TNIL		0
+#define LUA_TBOOLEAN		1
+#define LUA_TLIGHTUSERDATA	2
+#define LUA_TNUMBER		3
+#define LUA_TSTRING		4
+#define LUA_TTABLE		5
+#define LUA_TFUNCTION		6
+#define LUA_TUSERDATA		7
+#define LUA_TTHREAD		8
+
+#define LUA_NUMTYPES		9
+
+
+
+/* minimum Lua stack available to a C function */
+#define LUA_MINSTACK	20
+
+
+/* predefined values in the registry */
+#define LUA_RIDX_MAINTHREAD	1
+#define LUA_RIDX_GLOBALS	2
+#define LUA_RIDX_LAST		LUA_RIDX_GLOBALS
+
+
+/* type of numbers in Lua */
+typedef LUA_NUMBER lua_Number;
+
+
+/* type for integer functions */
+typedef LUA_INTEGER lua_Integer;
+
+/* unsigned integer type */
+typedef LUA_UNSIGNED lua_Unsigned;
+
+/* type for continuation-function contexts */
+typedef LUA_KCONTEXT lua_KContext;
+
+
+/*
+** Type for C functions registered with Lua
+*/
+typedef int (*lua_CFunction) (lua_State *L);
+
+/*
+** Type for continuation functions
+*/
+typedef int (*lua_KFunction) (lua_State *L, int status, lua_KContext ctx);
+
+
+/*
+** Type for functions that read/write blocks when loading/dumping Lua chunks
+*/
+typedef const char * (*lua_Reader) (lua_State *L, void *ud, size_t *sz);
+
+typedef int (*lua_Writer) (lua_State *L, const void *p, size_t sz, void *ud);
+
+
+/*
+** Type for memory-allocation functions
+*/
+typedef void * (*lua_Alloc) (void *ud, void *ptr, size_t osize, size_t nsize);
+
+
+/*
+** Type for warning functions
+*/
+typedef void (*lua_WarnFunction) (void *ud, const char *msg, int tocont);
+
+
+
+
+/*
+** generic extra include file
+*/
+#if defined(LUA_USER_H)
+#include LUA_USER_H
+#endif
+
+
+/*
+** RCS ident string
+*/
+extern const char lua_ident[];
+
+
+/*
+** state manipulation
+*/
+LUA_API lua_State *(lua_newstate) (lua_Alloc f, void *ud);
+LUA_API void       (lua_close) (lua_State *L);
+LUA_API lua_State *(lua_newthread) (lua_State *L);
+LUA_API int        (lua_resetthread) (lua_State *L);
+
+LUA_API lua_CFunction (lua_atpanic) (lua_State *L, lua_CFunction panicf);
+
+
+LUA_API lua_Number (lua_version) (lua_State *L);
+
+
+/*
+** basic stack manipulation
+*/
+LUA_API int   (lua_absindex) (lua_State *L, int idx);
+LUA_API int   (lua_gettop) (lua_State *L);
+LUA_API void  (lua_settop) (lua_State *L, int idx);
+LUA_API void  (lua_pushvalue) (lua_State *L, int idx);
+LUA_API void  (lua_rotate) (lua_State *L, int idx, int n);
+LUA_API void  (lua_copy) (lua_State *L, int fromidx, int toidx);
+LUA_API int   (lua_checkstack) (lua_State *L, int n);
+
+LUA_API void  (lua_xmove) (lua_State *from, lua_State *to, int n);
+
+
+/*
+** access functions (stack -> C)
+*/
+
+LUA_API int             (lua_isnumber) (lua_State *L, int idx);
+LUA_API int             (lua_isstring) (lua_State *L, int idx);
+LUA_API int             (lua_iscfunction) (lua_State *L, int idx);
+LUA_API int             (lua_isinteger) (lua_State *L, int idx);
+LUA_API int             (lua_isuserdata) (lua_State *L, int idx);
+LUA_API int             (lua_type) (lua_State *L, int idx);
+LUA_API const char     *(lua_typename) (lua_State *L, int tp);
+
+LUA_API lua_Number      (lua_tonumberx) (lua_State *L, int idx, int *isnum);
+LUA_API lua_Integer     (lua_tointegerx) (lua_State *L, int idx, int *isnum);
+LUA_API int             (lua_toboolean) (lua_State *L, int idx);
+LUA_API const char     *(lua_tolstring) (lua_State *L, int idx, size_t *len);
+LUA_API lua_Unsigned    (lua_rawlen) (lua_State *L, int idx);
+LUA_API lua_CFunction   (lua_tocfunction) (lua_State *L, int idx);
+LUA_API void	       *(lua_touserdata) (lua_State *L, int idx);
+LUA_API lua_State      *(lua_tothread) (lua_State *L, int idx);
+LUA_API const void     *(lua_topointer) (lua_State *L, int idx);
+
+
+/*
+** Comparison and arithmetic functions
+*/
+
+#define LUA_OPADD	0	/* ORDER TM, ORDER OP */
+#define LUA_OPSUB	1
+#define LUA_OPMUL	2
+#define LUA_OPMOD	3
+#define LUA_OPPOW	4
+#define LUA_OPDIV	5
+#define LUA_OPIDIV	6
+#define LUA_OPBAND	7
+#define LUA_OPBOR	8
+#define LUA_OPBXOR	9
+#define LUA_OPSHL	10
+#define LUA_OPSHR	11
+#define LUA_OPUNM	12
+#define LUA_OPBNOT	13
+
+LUA_API void  (lua_arith) (lua_State *L, int op);
+
+#define LUA_OPEQ	0
+#define LUA_OPLT	1
+#define LUA_OPLE	2
+
+LUA_API int   (lua_rawequal) (lua_State *L, int idx1, int idx2);
+LUA_API int   (lua_compare) (lua_State *L, int idx1, int idx2, int op);
+
+
+/*
+** push functions (C -> stack)
+*/
+LUA_API void        (lua_pushnil) (lua_State *L);
+LUA_API void        (lua_pushnumber) (lua_State *L, lua_Number n);
+LUA_API void        (lua_pushinteger) (lua_State *L, lua_Integer n);
+LUA_API const char *(lua_pushlstring) (lua_State *L, const char *s, size_t len);
+LUA_API const char *(lua_pushstring) (lua_State *L, const char *s);
+LUA_API const char *(lua_pushvfstring) (lua_State *L, const char *fmt,
+                                                      va_list argp);
+LUA_API const char *(lua_pushfstring) (lua_State *L, const char *fmt, ...);
+LUA_API void  (lua_pushcclosure) (lua_State *L, lua_CFunction fn, int n);
+LUA_API void  (lua_pushboolean) (lua_State *L, int b);
+LUA_API void  (lua_pushlightuserdata) (lua_State *L, void *p);
+LUA_API int   (lua_pushthread) (lua_State *L);
+
+
+/*
+** get functions (Lua -> stack)
+*/
+LUA_API int (lua_getglobal) (lua_State *L, const char *name);
+LUA_API int (lua_gettable) (lua_State *L, int idx);
+LUA_API int (lua_getfield) (lua_State *L, int idx, const char *k);
+LUA_API int (lua_geti) (lua_State *L, int idx, lua_Integer n);
+LUA_API int (lua_rawget) (lua_State *L, int idx);
+LUA_API int (lua_rawgeti) (lua_State *L, int idx, lua_Integer n);
+LUA_API int (lua_rawgetp) (lua_State *L, int idx, const void *p);
+
+LUA_API void  (lua_createtable) (lua_State *L, int narr, int nrec);
+LUA_API void *(lua_newuserdatauv) (lua_State *L, size_t sz, int nuvalue);
+LUA_API int   (lua_getmetatable) (lua_State *L, int objindex);
+LUA_API int  (lua_getiuservalue) (lua_State *L, int idx, int n);
+
+
+/*
+** set functions (stack -> Lua)
+*/
+LUA_API void  (lua_setglobal) (lua_State *L, const char *name);
+LUA_API void  (lua_settable) (lua_State *L, int idx);
+LUA_API void  (lua_setfield) (lua_State *L, int idx, const char *k);
+LUA_API void  (lua_seti) (lua_State *L, int idx, lua_Integer n);
+LUA_API void  (lua_rawset) (lua_State *L, int idx);
+LUA_API void  (lua_rawseti) (lua_State *L, int idx, lua_Integer n);
+LUA_API void  (lua_rawsetp) (lua_State *L, int idx, const void *p);
+LUA_API int   (lua_setmetatable) (lua_State *L, int objindex);
+LUA_API int   (lua_setiuservalue) (lua_State *L, int idx, int n);
+
+
+/*
+** 'load' and 'call' functions (load and run Lua code)
+*/
+LUA_API void  (lua_callk) (lua_State *L, int nargs, int nresults,
+                           lua_KContext ctx, lua_KFunction k);
+#define lua_call(L,n,r)		lua_callk(L, (n), (r), 0, NULL)
+
+LUA_API int   (lua_pcallk) (lua_State *L, int nargs, int nresults, int errfunc,
+                            lua_KContext ctx, lua_KFunction k);
+#define lua_pcall(L,n,r,f)	lua_pcallk(L, (n), (r), (f), 0, NULL)
+
+LUA_API int   (lua_load) (lua_State *L, lua_Reader reader, void *dt,
+                          const char *chunkname, const char *mode);
+
+LUA_API int (lua_dump) (lua_State *L, lua_Writer writer, void *data, int strip);
+
+
+/*
+** coroutine functions
+*/
+LUA_API int  (lua_yieldk)     (lua_State *L, int nresults, lua_KContext ctx,
+                               lua_KFunction k);
+LUA_API int  (lua_resume)     (lua_State *L, lua_State *from, int narg,
+                               int *nres);
+LUA_API int  (lua_status)     (lua_State *L);
+LUA_API int (lua_isyieldable) (lua_State *L);
+
+#define lua_yield(L,n)		lua_yieldk(L, (n), 0, NULL)
+
+
+/*
+** Warning-related functions
+*/
+LUA_API void (lua_setwarnf) (lua_State *L, lua_WarnFunction f, void *ud);
+LUA_API void (lua_warning)  (lua_State *L, const char *msg, int tocont);
+
+
+/*
+** garbage-collection function and options
+*/
+
+#define LUA_GCSTOP		0
+#define LUA_GCRESTART		1
+#define LUA_GCCOLLECT		2
+#define LUA_GCCOUNT		3
+#define LUA_GCCOUNTB		4
+#define LUA_GCSTEP		5
+#define LUA_GCSETPAUSE		6
+#define LUA_GCSETSTEPMUL	7
+#define LUA_GCISRUNNING		9
+#define LUA_GCGEN		10
+#define LUA_GCINC		11
+
+LUA_API int (lua_gc) (lua_State *L, int what, ...);
+
+
+/*
+** miscellaneous functions
+*/
+
+LUA_API int   (lua_error) (lua_State *L);
+
+LUA_API int   (lua_next) (lua_State *L, int idx);
+
+LUA_API void  (lua_concat) (lua_State *L, int n);
+LUA_API void  (lua_len)    (lua_State *L, int idx);
+
+LUA_API size_t   (lua_stringtonumber) (lua_State *L, const char *s);
+
+LUA_API lua_Alloc (lua_getallocf) (lua_State *L, void **ud);
+LUA_API void      (lua_setallocf) (lua_State *L, lua_Alloc f, void *ud);
+
+LUA_API void  (lua_toclose) (lua_State *L, int idx);
+
+
+/*
+** {==============================================================
+** some useful macros
+** ===============================================================
+*/
+
+#define lua_getextraspace(L)	((void *)((char *)(L) - LUA_EXTRASPACE))
+
+#define lua_tonumber(L,i)	lua_tonumberx(L,(i),NULL)
+#define lua_tointeger(L,i)	lua_tointegerx(L,(i),NULL)
+
+#define lua_pop(L,n)		lua_settop(L, -(n)-1)
+
+#define lua_newtable(L)		lua_createtable(L, 0, 0)
+
+#define lua_register(L,n,f) (lua_pushcfunction(L, (f)), lua_setglobal(L, (n)))
+
+#define lua_pushcfunction(L,f)	lua_pushcclosure(L, (f), 0)
+
+#define lua_isfunction(L,n)	(lua_type(L, (n)) == LUA_TFUNCTION)
+#define lua_istable(L,n)	(lua_type(L, (n)) == LUA_TTABLE)
+#define lua_islightuserdata(L,n)	(lua_type(L, (n)) == LUA_TLIGHTUSERDATA)
+#define lua_isnil(L,n)		(lua_type(L, (n)) == LUA_TNIL)
+#define lua_isboolean(L,n)	(lua_type(L, (n)) == LUA_TBOOLEAN)
+#define lua_isthread(L,n)	(lua_type(L, (n)) == LUA_TTHREAD)
+#define lua_isnone(L,n)		(lua_type(L, (n)) == LUA_TNONE)
+#define lua_isnoneornil(L, n)	(lua_type(L, (n)) <= 0)
+
+#define lua_pushliteral(L, s)	lua_pushstring(L, "" s)
+
+#define lua_pushglobaltable(L)  \
+	((void)lua_rawgeti(L, LUA_REGISTRYINDEX, LUA_RIDX_GLOBALS))
+
+#define lua_tostring(L,i)	lua_tolstring(L, (i), NULL)
+
+
+#define lua_insert(L,idx)	lua_rotate(L, (idx), 1)
+
+#define lua_remove(L,idx)	(lua_rotate(L, (idx), -1), lua_pop(L, 1))
+
+#define lua_replace(L,idx)	(lua_copy(L, -1, (idx)), lua_pop(L, 1))
+
+/* }============================================================== */
+
+
+/*
+** {==============================================================
+** compatibility macros
+** ===============================================================
+*/
+#if defined(LUA_COMPAT_APIINTCASTS)
+
+#define lua_pushunsigned(L,n)	lua_pushinteger(L, (lua_Integer)(n))
+#define lua_tounsignedx(L,i,is)	((lua_Unsigned)lua_tointegerx(L,i,is))
+#define lua_tounsigned(L,i)	lua_tounsignedx(L,(i),NULL)
+
+#endif
+
+#define lua_newuserdata(L,s)	lua_newuserdatauv(L,s,1)
+#define lua_getuservalue(L,idx)	lua_getiuservalue(L,idx,1)
+#define lua_setuservalue(L,idx)	lua_setiuservalue(L,idx,1)
+
+#define LUA_NUMTAGS		LUA_NUMTYPES
+
+/* }============================================================== */
+
+/*
+** {======================================================================
+** Debug API
+** =======================================================================
+*/
+
+
+/*
+** Event codes
+*/
+#define LUA_HOOKCALL	0
+#define LUA_HOOKRET	1
+#define LUA_HOOKLINE	2
+#define LUA_HOOKCOUNT	3
+#define LUA_HOOKTAILCALL 4
+
+
+/*
+** Event masks
+*/
+#define LUA_MASKCALL	(1 << LUA_HOOKCALL)
+#define LUA_MASKRET	(1 << LUA_HOOKRET)
+#define LUA_MASKLINE	(1 << LUA_HOOKLINE)
+#define LUA_MASKCOUNT	(1 << LUA_HOOKCOUNT)
+
+typedef struct lua_Debug lua_Debug;  /* activation record */
+
+
+/* Functions to be called by the debugger in specific events */
+typedef void (*lua_Hook) (lua_State *L, lua_Debug *ar);
+
+
+LUA_API int (lua_getstack) (lua_State *L, int level, lua_Debug *ar);
+LUA_API int (lua_getinfo) (lua_State *L, const char *what, lua_Debug *ar);
+LUA_API const char *(lua_getlocal) (lua_State *L, const lua_Debug *ar, int n);
+LUA_API const char *(lua_setlocal) (lua_State *L, const lua_Debug *ar, int n);
+LUA_API const char *(lua_getupvalue) (lua_State *L, int funcindex, int n);
+LUA_API const char *(lua_setupvalue) (lua_State *L, int funcindex, int n);
+
+LUA_API void *(lua_upvalueid) (lua_State *L, int fidx, int n);
+LUA_API void  (lua_upvaluejoin) (lua_State *L, int fidx1, int n1,
+                                               int fidx2, int n2);
+
+LUA_API void (lua_sethook) (lua_State *L, lua_Hook func, int mask, int count);
+LUA_API lua_Hook (lua_gethook) (lua_State *L);
+LUA_API int (lua_gethookmask) (lua_State *L);
+LUA_API int (lua_gethookcount) (lua_State *L);
+
+LUA_API int (lua_setcstacklimit) (lua_State *L, unsigned int limit);
+
+struct lua_Debug {
+  int event;
+  const char *name;	/* (n) */
+  const char *namewhat;	/* (n) 'global', 'local', 'field', 'method' */
+  const char *what;	/* (S) 'Lua', 'C', 'main', 'tail' */
+  const char *source;	/* (S) */
+  size_t srclen;	/* (S) */
+  int currentline;	/* (l) */
+  int linedefined;	/* (S) */
+  int lastlinedefined;	/* (S) */
+  unsigned char nups;	/* (u) number of upvalues */
+  unsigned char nparams;/* (u) number of parameters */
+  char isvararg;        /* (u) */
+  char istailcall;	/* (t) */
+  unsigned short ftransfer;   /* (r) index of first value transferred */
+  unsigned short ntransfer;   /* (r) number of transferred values */
+  char short_src[LUA_IDSIZE]; /* (S) */
+  /* private part */
+  struct CallInfo *i_ci;  /* active function */
+};
+
+/* }====================================================================== */
+
+
+/******************************************************************************
+* Copyright (C) 1994-2020 Lua.org, PUC-Rio.
+*
+* Permission is hereby granted, free of charge, to any person obtaining
+* a copy of this software and associated documentation files (the
+* "Software"), to deal in the Software without restriction, including
+* without limitation the rights to use, copy, modify, merge, publish,
+* distribute, sublicense, and/or sell copies of the Software, and to
+* permit persons to whom the Software is furnished to do so, subject to
+* the following conditions:
+*
+* The above copyright notice and this permission notice shall be
+* included in all copies or substantial portions of the Software.
+*
+* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+******************************************************************************/
+
+
+#endif
diff --git a/test/external/lua-5.4.0/src/lua.hpp b/test/external/lua-5.4.0/src/lua.hpp
new file mode 100644
index 0000000..ec417f5
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lua.hpp
@@ -0,0 +1,9 @@
+// lua.hpp
+// Lua header files for C++
+// <<extern "C">> not supplied automatically because Lua also compiles as C++
+
+extern "C" {
+#include "lua.h"
+#include "lualib.h"
+#include "lauxlib.h"
+}
diff --git a/test/external/lua-5.4.0/src/luac b/test/external/lua-5.4.0/src/luac
new file mode 100755
index 0000000..00e7a27
--- /dev/null
+++ b/test/external/lua-5.4.0/src/luac
diff --git a/test/external/lua-5.4.0/src/luac.c b/test/external/lua-5.4.0/src/luac.c
new file mode 100644
index 0000000..56ddc41
--- /dev/null
+++ b/test/external/lua-5.4.0/src/luac.c
@@ -0,0 +1,724 @@
+/*
+** $Id: luac.c $
+** Lua compiler (saves bytecodes to files; also lists bytecodes)
+** See Copyright Notice in lua.h
+*/
+
+#define luac_c
+#define LUA_CORE
+
+#include "lprefix.h"
+
+#include <ctype.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "lua.h"
+#include "lauxlib.h"
+
+#include "ldebug.h"
+#include "lobject.h"
+#include "lopcodes.h"
+#include "lopnames.h"
+#include "lstate.h"
+#include "lundump.h"
+
+static void PrintFunction(const Proto* f, int full);
+#define luaU_print	PrintFunction
+
+#define PROGNAME	"luac"		/* default program name */
+#define OUTPUT		PROGNAME ".out"	/* default output file */
+
+static int listing=0;			/* list bytecodes? */
+static int dumping=1;			/* dump bytecodes? */
+static int stripping=0;			/* strip debug information? */
+static char Output[]={ OUTPUT };	/* default output file name */
+static const char* output=Output;	/* actual output file name */
+static const char* progname=PROGNAME;	/* actual program name */
+static TString **tmname;
+
+static void fatal(const char* message)
+{
+ fprintf(stderr,"%s: %s\n",progname,message);
+ exit(EXIT_FAILURE);
+}
+
+static void cannot(const char* what)
+{
+ fprintf(stderr,"%s: cannot %s %s: %s\n",progname,what,output,strerror(errno));
+ exit(EXIT_FAILURE);
+}
+
+static void usage(const char* message)
+{
+ if (*message=='-')
+  fprintf(stderr,"%s: unrecognized option '%s'\n",progname,message);
+ else
+  fprintf(stderr,"%s: %s\n",progname,message);
+ fprintf(stderr,
+  "usage: %s [options] [filenames]\n"
+  "Available options are:\n"
+  "  -l       list (use -l -l for full listing)\n"
+  "  -o name  output to file 'name' (default is \"%s\")\n"
+  "  -p       parse only\n"
+  "  -s       strip debug information\n"
+  "  -v       show version information\n"
+  "  --       stop handling options\n"
+  "  -        stop handling options and process stdin\n"
+  ,progname,Output);
+ exit(EXIT_FAILURE);
+}
+
+#define IS(s)	(strcmp(argv[i],s)==0)
+
+static int doargs(int argc, char* argv[])
+{
+ int i;
+ int version=0;
+ if (argv[0]!=NULL && *argv[0]!=0) progname=argv[0];
+ for (i=1; i<argc; i++)
+ {
+  if (*argv[i]!='-')			/* end of options; keep it */
+   break;
+  else if (IS("--"))			/* end of options; skip it */
+  {
+   ++i;
+   if (version) ++version;
+   break;
+  }
+  else if (IS("-"))			/* end of options; use stdin */
+   break;
+  else if (IS("-l"))			/* list */
+   ++listing;
+  else if (IS("-o"))			/* output file */
+  {
+   output=argv[++i];
+   if (output==NULL || *output==0 || (*output=='-' && output[1]!=0))
+    usage("'-o' needs argument");
+   if (IS("-")) output=NULL;
+  }
+  else if (IS("-p"))			/* parse only */
+   dumping=0;
+  else if (IS("-s"))			/* strip debug information */
+   stripping=1;
+  else if (IS("-v"))			/* show version */
+   ++version;
+  else					/* unknown option */
+   usage(argv[i]);
+ }
+ if (i==argc && (listing || !dumping))
+ {
+  dumping=0;
+  argv[--i]=Output;
+ }
+ if (version)
+ {
+  printf("%s\n",LUA_COPYRIGHT);
+  if (version==argc-1) exit(EXIT_SUCCESS);
+ }
+ return i;
+}
+
+#define FUNCTION "(function()end)();"
+
+static const char* reader(lua_State* L, void* ud, size_t* size)
+{
+ UNUSED(L);
+ if ((*(int*)ud)--)
+ {
+  *size=sizeof(FUNCTION)-1;
+  return FUNCTION;
+ }
+ else
+ {
+  *size=0;
+  return NULL;
+ }
+}
+
+#define toproto(L,i) getproto(s2v(L->top+(i)))
+
+static const Proto* combine(lua_State* L, int n)
+{
+ if (n==1)
+  return toproto(L,-1);
+ else
+ {
+  Proto* f;
+  int i=n;
+  if (lua_load(L,reader,&i,"=(" PROGNAME ")",NULL)!=LUA_OK) fatal(lua_tostring(L,-1));
+  f=toproto(L,-1);
+  for (i=0; i<n; i++)
+  {
+   f->p[i]=toproto(L,i-n-1);
+   if (f->p[i]->sizeupvalues>0) f->p[i]->upvalues[0].instack=0;
+  }
+  f->sizelineinfo=0;
+  return f;
+ }
+}
+
+static int writer(lua_State* L, const void* p, size_t size, void* u)
+{
+ UNUSED(L);
+ return (fwrite(p,size,1,(FILE*)u)!=1) && (size!=0);
+}
+
+static int pmain(lua_State* L)
+{
+ int argc=(int)lua_tointeger(L,1);
+ char** argv=(char**)lua_touserdata(L,2);
+ const Proto* f;
+ int i;
+ tmname=G(L)->tmname;
+ if (!lua_checkstack(L,argc)) fatal("too many input files");
+ for (i=0; i<argc; i++)
+ {
+  const char* filename=IS("-") ? NULL : argv[i];
+  if (luaL_loadfile(L,filename)!=LUA_OK) fatal(lua_tostring(L,-1));
+ }
+ f=combine(L,argc);
+ if (listing) luaU_print(f,listing>1);
+ if (dumping)
+ {
+  FILE* D= (output==NULL) ? stdout : fopen(output,"wb");
+  if (D==NULL) cannot("open");
+  lua_lock(L);
+  luaU_dump(L,f,writer,D,stripping);
+  lua_unlock(L);
+  if (ferror(D)) cannot("write");
+  if (fclose(D)) cannot("close");
+ }
+ return 0;
+}
+
+int main(int argc, char* argv[])
+{
+ lua_State* L;
+ int i=doargs(argc,argv);
+ argc-=i; argv+=i;
+ if (argc<=0) usage("no input files given");
+ L=luaL_newstate();
+ if (L==NULL) fatal("cannot create state: not enough memory");
+ lua_pushcfunction(L,&pmain);
+ lua_pushinteger(L,argc);
+ lua_pushlightuserdata(L,argv);
+ if (lua_pcall(L,2,0,0)!=LUA_OK) fatal(lua_tostring(L,-1));
+ lua_close(L);
+ return EXIT_SUCCESS;
+}
+
+/*
+** print bytecodes
+*/
+
+#define UPVALNAME(x) ((f->upvalues[x].name) ? getstr(f->upvalues[x].name) : "-")
+#define VOID(p) ((const void*)(p))
+#define eventname(i) (getstr(tmname[i]))
+
+static void PrintString(const TString* ts)
+{
+ const char* s=getstr(ts);
+ size_t i,n=tsslen(ts);
+ printf("\"");
+ for (i=0; i<n; i++)
+ {
+  int c=(int)(unsigned char)s[i];
+  switch (c)
+  {
+   case '"':
+	printf("\\\"");
+	break;
+   case '\\':
+	printf("\\\\");
+	break;
+   case '\a':
+	printf("\\a");
+	break;
+   case '\b':
+	printf("\\b");
+	break;
+   case '\f':
+	printf("\\f");
+	break;
+   case '\n':
+	printf("\\n");
+	break;
+   case '\r':
+	printf("\\r");
+	break;
+   case '\t':
+	printf("\\t");
+	break;
+   case '\v':
+	printf("\\v");
+	break;
+   default:
+	if (isprint(c)) printf("%c",c); else printf("\\%03d",c);
+	break;
+  }
+ }
+ printf("\"");
+}
+
+static void PrintType(const Proto* f, int i)
+{
+ const TValue* o=&f->k[i];
+ switch (ttypetag(o))
+ {
+  case LUA_VNIL:
+	printf("N");
+	break;
+  case LUA_VFALSE:
+  case LUA_VTRUE:
+	printf("B");
+	break;
+  case LUA_VNUMFLT:
+	printf("F");
+	break;
+  case LUA_VNUMINT:
+	printf("I");
+	break;
+  case LUA_VSHRSTR:
+  case LUA_VLNGSTR:
+	printf("S");
+	break;
+  default:				/* cannot happen */
+	printf("?%d",ttypetag(o));
+	break;
+ }
+ printf("\t");
+}
+
+static void PrintConstant(const Proto* f, int i)
+{
+ const TValue* o=&f->k[i];
+ switch (ttypetag(o))
+ {
+  case LUA_VNIL:
+	printf("nil");
+	break;
+  case LUA_VFALSE:
+	printf("false");
+	break;
+  case LUA_VTRUE:
+	printf("true");
+	break;
+  case LUA_VNUMFLT:
+	{
+	char buff[100];
+	sprintf(buff,LUA_NUMBER_FMT,fltvalue(o));
+	printf("%s",buff);
+	if (buff[strspn(buff,"-0123456789")]=='\0') printf(".0");
+	break;
+	}
+  case LUA_VNUMINT:
+	printf(LUA_INTEGER_FMT,ivalue(o));
+	break;
+  case LUA_VSHRSTR:
+  case LUA_VLNGSTR:
+	PrintString(tsvalue(o));
+	break;
+  default:				/* cannot happen */
+	printf("?%d",ttypetag(o));
+	break;
+ }
+}
+
+#define COMMENT		"\t; "
+#define EXTRAARG	GETARG_Ax(code[pc+1])
+#define EXTRAARGC	(EXTRAARG*(MAXARG_C+1))
+#define ISK		(isk ? "k" : "")
+
+static void PrintCode(const Proto* f)
+{
+ const Instruction* code=f->code;
+ int pc,n=f->sizecode;
+ for (pc=0; pc<n; pc++)
+ {
+  Instruction i=code[pc];
+  OpCode o=GET_OPCODE(i);
+  int a=GETARG_A(i);
+  int b=GETARG_B(i);
+  int c=GETARG_C(i);
+  int ax=GETARG_Ax(i);
+  int bx=GETARG_Bx(i);
+  int sb=GETARG_sB(i);
+  int sc=GETARG_sC(i);
+  int sbx=GETARG_sBx(i);
+  int isk=GETARG_k(i);
+  int line=luaG_getfuncline(f,pc);
+  printf("\t%d\t",pc+1);
+  if (line>0) printf("[%d]\t",line); else printf("[-]\t");
+  printf("%-9s\t",opnames[o]);
+  switch (o)
+  {
+   case OP_MOVE:
+	printf("%d %d",a,b);
+	break;
+   case OP_LOADI:
+	printf("%d %d",a,sbx);
+	break;
+   case OP_LOADF:
+	printf("%d %d",a,sbx);
+	break;
+   case OP_LOADK:
+	printf("%d %d",a,bx);
+	printf(COMMENT); PrintConstant(f,bx);
+	break;
+   case OP_LOADKX:
+	printf("%d",a);
+	printf(COMMENT); PrintConstant(f,EXTRAARG);
+	break;
+   case OP_LOADFALSE:
+	printf("%d",a);
+	break;
+   case OP_LFALSESKIP:
+	printf("%d",a);
+	break;
+   case OP_LOADTRUE:
+	printf("%d",a);
+	break;
+   case OP_LOADNIL:
+	printf("%d %d",a,b);
+	printf(COMMENT "%d out",b+1);
+	break;
+   case OP_GETUPVAL:
+	printf("%d %d",a,b);
+	printf(COMMENT "%s",UPVALNAME(b));
+	break;
+   case OP_SETUPVAL:
+	printf("%d %d",a,b);
+	printf(COMMENT "%s",UPVALNAME(b));
+	break;
+   case OP_GETTABUP:
+	printf("%d %d %d",a,b,c);
+	printf(COMMENT "%s",UPVALNAME(b));
+	printf(" "); PrintConstant(f,c);
+	break;
+   case OP_GETTABLE:
+	printf("%d %d %d",a,b,c);
+	break;
+   case OP_GETI:
+	printf("%d %d %d",a,b,c);
+	break;
+   case OP_GETFIELD:
+	printf("%d %d %d",a,b,c);
+	printf(COMMENT); PrintConstant(f,c);
+	break;
+   case OP_SETTABUP:
+	printf("%d %d %d%s",a,b,c,ISK);
+	printf(COMMENT "%s",UPVALNAME(a));
+	printf(" "); PrintConstant(f,b);
+	if (isk) { printf(" "); PrintConstant(f,c); }
+	break;
+   case OP_SETTABLE:
+	printf("%d %d %d%s",a,b,c,ISK);
+	if (isk) { printf(COMMENT); PrintConstant(f,c); }
+	break;
+   case OP_SETI:
+	printf("%d %d %d%s",a,b,c,ISK);
+	if (isk) { printf(COMMENT); PrintConstant(f,c); }
+	break;
+   case OP_SETFIELD:
+	printf("%d %d %d%s",a,b,c,ISK);
+	printf(COMMENT); PrintConstant(f,b);
+	if (isk) { printf(" "); PrintConstant(f,c); }
+	break;
+   case OP_NEWTABLE:
+	printf("%d %d %d",a,b,c);
+	printf(COMMENT "%d",c+EXTRAARGC);
+	break;
+   case OP_SELF:
+	printf("%d %d %d%s",a,b,c,ISK);
+	if (isk) { printf(COMMENT); PrintConstant(f,c); }
+	break;
+   case OP_ADDI:
+	printf("%d %d %d",a,b,sc);
+	break;
+   case OP_ADDK:
+	printf("%d %d %d",a,b,c);
+	printf(COMMENT); PrintConstant(f,c);
+	break;
+   case OP_SUBK:
+	printf("%d %d %d",a,b,c);
+	printf(COMMENT); PrintConstant(f,c);
+	break;
+   case OP_MULK:
+	printf("%d %d %d",a,b,c);
+	printf(COMMENT); PrintConstant(f,c);
+	break;
+   case OP_MODK:
+	printf("%d %d %d",a,b,c);
+	printf(COMMENT); PrintConstant(f,c);
+	break;
+   case OP_POWK:
+	printf("%d %d %d",a,b,c);
+	printf(COMMENT); PrintConstant(f,c);
+	break;
+   case OP_DIVK:
+	printf("%d %d %d",a,b,c);
+	printf(COMMENT); PrintConstant(f,c);
+	break;
+   case OP_IDIVK:
+	printf("%d %d %d",a,b,c);
+	printf(COMMENT); PrintConstant(f,c);
+	break;
+   case OP_BANDK:
+	printf("%d %d %d",a,b,c);
+	printf(COMMENT); PrintConstant(f,c);
+	break;
+   case OP_BORK:
+	printf("%d %d %d",a,b,c);
+	printf(COMMENT); PrintConstant(f,c);
+	break;
+   case OP_BXORK:
+	printf("%d %d %d",a,b,c);
+	printf(COMMENT); PrintConstant(f,c);
+	break;
+   case OP_SHRI:
+	printf("%d %d %d",a,b,sc);
+	break;
+   case OP_SHLI:
+	printf("%d %d %d",a,b,sc);
+	break;
+   case OP_ADD:
+	printf("%d %d %d",a,b,c);
+	break;
+   case OP_SUB:
+	printf("%d %d %d",a,b,c);
+	break;
+   case OP_MUL:
+	printf("%d %d %d",a,b,c);
+	break;
+   case OP_MOD:
+	printf("%d %d %d",a,b,c);
+	break;
+   case OP_POW:
+	printf("%d %d %d",a,b,c);
+	break;
+   case OP_DIV:
+	printf("%d %d %d",a,b,c);
+	break;
+   case OP_IDIV:
+	printf("%d %d %d",a,b,c);
+	break;
+   case OP_BAND:
+	printf("%d %d %d",a,b,c);
+	break;
+   case OP_BOR:
+	printf("%d %d %d",a,b,c);
+	break;
+   case OP_BXOR:
+	printf("%d %d %d",a,b,c);
+	break;
+   case OP_SHL:
+	printf("%d %d %d",a,b,c);
+	break;
+   case OP_SHR:
+	printf("%d %d %d",a,b,c);
+	break;
+   case OP_MMBIN:
+	printf("%d %d %d",a,b,c);
+	printf(COMMENT "%s",eventname(c));
+	break;
+   case OP_MMBINI:
+	printf("%d %d %d %d",a,sb,c,isk);
+	printf(COMMENT "%s",eventname(c));
+	if (isk) printf(" flip");
+	break;
+   case OP_MMBINK:
+	printf("%d %d %d %d",a,b,c,isk);
+	printf(COMMENT "%s ",eventname(c)); PrintConstant(f,b);
+	if (isk) printf(" flip");
+	break;
+   case OP_UNM:
+	printf("%d %d",a,b);
+	break;
+   case OP_BNOT:
+	printf("%d %d",a,b);
+	break;
+   case OP_NOT:
+	printf("%d %d",a,b);
+	break;
+   case OP_LEN:
+	printf("%d %d",a,b);
+	break;
+   case OP_CONCAT:
+	printf("%d %d",a,b);
+	break;
+   case OP_CLOSE:
+	printf("%d",a);
+	break;
+   case OP_TBC:
+	printf("%d",a);
+	break;
+   case OP_JMP:
+	printf("%d",GETARG_sJ(i));
+	printf(COMMENT "to %d",GETARG_sJ(i)+pc+2);
+	break;
+   case OP_EQ:
+	printf("%d %d %d",a,b,isk);
+	break;
+   case OP_LT:
+	printf("%d %d %d",a,b,isk);
+	break;
+   case OP_LE:
+	printf("%d %d %d",a,b,isk);
+	break;
+   case OP_EQK:
+	printf("%d %d %d",a,b,isk);
+	printf(COMMENT); PrintConstant(f,b);
+	break;
+   case OP_EQI:
+	printf("%d %d %d",a,sb,isk);
+	break;
+   case OP_LTI:
+	printf("%d %d %d",a,sb,isk);
+	break;
+   case OP_LEI:
+	printf("%d %d %d",a,sb,isk);
+	break;
+   case OP_GTI:
+	printf("%d %d %d",a,sb,isk);
+	break;
+   case OP_GEI:
+	printf("%d %d %d",a,sb,isk);
+	break;
+   case OP_TEST:
+	printf("%d %d",a,isk);
+	break;
+   case OP_TESTSET:
+	printf("%d %d %d",a,b,isk);
+	break;
+   case OP_CALL:
+	printf("%d %d %d",a,b,c);
+	printf(COMMENT);
+	if (b==0) printf("all in "); else printf("%d in ",b-1);
+	if (c==0) printf("all out"); else printf("%d out",c-1);
+	break;
+   case OP_TAILCALL:
+	printf("%d %d %d",a,b,c);
+	printf(COMMENT "%d in",b-1);
+	break;
+   case OP_RETURN:
+	printf("%d %d %d",a,b,c);
+	printf(COMMENT);
+	if (b==0) printf("all out"); else printf("%d out",b-1);
+	break;
+   case OP_RETURN0:
+	break;
+   case OP_RETURN1:
+	printf("%d",a);
+	break;
+   case OP_FORLOOP:
+	printf("%d %d",a,bx);
+	printf(COMMENT "to %d",pc-bx+2);
+	break;
+   case OP_FORPREP:
+	printf("%d %d",a,bx);
+	printf(COMMENT "to %d",pc+bx+2);
+	break;
+   case OP_TFORPREP:
+	printf("%d %d",a,bx);
+	printf(COMMENT "to %d",pc+bx+2);
+	break;
+   case OP_TFORCALL:
+	printf("%d %d",a,c);
+	break;
+   case OP_TFORLOOP:
+	printf("%d %d",a,bx);
+	printf(COMMENT "to %d",pc-bx+2);
+	break;
+   case OP_SETLIST:
+	printf("%d %d %d",a,b,c);
+	if (isk) printf(COMMENT "%d",c+EXTRAARGC);
+	break;
+   case OP_CLOSURE:
+	printf("%d %d",a,bx);
+	printf(COMMENT "%p",VOID(f->p[bx]));
+	break;
+   case OP_VARARG:
+	printf("%d %d",a,c);
+	printf(COMMENT);
+	if (c==0) printf("all out"); else printf("%d out",c-1);
+	break;
+   case OP_VARARGPREP:
+	printf("%d",a);
+	break;
+   case OP_EXTRAARG:
+	printf("%d",ax);
+	break;
+#if 0
+   default:
+	printf("%d %d %d",a,b,c);
+	printf(COMMENT "not handled");
+	break;
+#endif
+  }
+  printf("\n");
+ }
+}
+
+
+#define SS(x)	((x==1)?"":"s")
+#define S(x)	(int)(x),SS(x)
+
+static void PrintHeader(const Proto* f)
+{
+ const char* s=f->source ? getstr(f->source) : "=?";
+ if (*s=='@' || *s=='=')
+  s++;
+ else if (*s==LUA_SIGNATURE[0])
+  s="(bstring)";
+ else
+  s="(string)";
+ printf("\n%s <%s:%d,%d> (%d instruction%s at %p)\n",
+	(f->linedefined==0)?"main":"function",s,
+	f->linedefined,f->lastlinedefined,
+	S(f->sizecode),VOID(f));
+ printf("%d%s param%s, %d slot%s, %d upvalue%s, ",
+	(int)(f->numparams),f->is_vararg?"+":"",SS(f->numparams),
+	S(f->maxstacksize),S(f->sizeupvalues));
+ printf("%d local%s, %d constant%s, %d function%s\n",
+	S(f->sizelocvars),S(f->sizek),S(f->sizep));
+}
+
+static void PrintDebug(const Proto* f)
+{
+ int i,n;
+ n=f->sizek;
+ printf("constants (%d) for %p:\n",n,VOID(f));
+ for (i=0; i<n; i++)
+ {
+  printf("\t%d\t",i);
+  PrintType(f,i);
+  PrintConstant(f,i);
+  printf("\n");
+ }
+ n=f->sizelocvars;
+ printf("locals (%d) for %p:\n",n,VOID(f));
+ for (i=0; i<n; i++)
+ {
+  printf("\t%d\t%s\t%d\t%d\n",
+  i,getstr(f->locvars[i].varname),f->locvars[i].startpc+1,f->locvars[i].endpc+1);
+ }
+ n=f->sizeupvalues;
+ printf("upvalues (%d) for %p:\n",n,VOID(f));
+ for (i=0; i<n; i++)
+ {
+  printf("\t%d\t%s\t%d\t%d\n",
+  i,UPVALNAME(i),f->upvalues[i].instack,f->upvalues[i].idx);
+ }
+}
+
+static void PrintFunction(const Proto* f, int full)
+{
+ int i,n=f->sizep;
+ PrintHeader(f);
+ PrintCode(f);
+ if (full) PrintDebug(f);
+ for (i=0; i<n; i++) PrintFunction(f->p[i],full);
+}
diff --git a/test/external/lua-5.4.0/src/luaconf.h b/test/external/lua-5.4.0/src/luaconf.h
new file mode 100644
index 0000000..bdf927e
--- /dev/null
+++ b/test/external/lua-5.4.0/src/luaconf.h
@@ -0,0 +1,776 @@
+/*
+** $Id: luaconf.h $
+** Configuration file for Lua
+** See Copyright Notice in lua.h
+*/
+
+
+#ifndef luaconf_h
+#define luaconf_h
+
+#include <limits.h>
+#include <stddef.h>
+
+
+/*
+** ===================================================================
+** General Configuration File for Lua
+**
+** Some definitions here can be changed externally, through the
+** compiler (e.g., with '-D' options). Those are protected by
+** '#if !defined' guards. However, several other definitions should
+** be changed directly here, either because they affect the Lua
+** ABI (by making the changes here, you ensure that all software
+** connected to Lua, such as C libraries, will be compiled with the
+** same configuration); or because they are seldom changed.
+**
+** Search for "@@" to find all configurable definitions.
+** ===================================================================
+*/
+
+
+/*
+** {====================================================================
+** System Configuration: macros to adapt (if needed) Lua to some
+** particular platform, for instance restricting it to C89.
+** =====================================================================
+*/
+
+/*
+@@ LUAI_MAXCSTACK defines the maximum depth for nested calls and
+** also limits the maximum depth of other recursive algorithms in
+** the implementation, such as syntactic analysis. A value too
+** large may allow the interpreter to crash (C-stack overflow).
+** The default value seems ok for regular machines, but may be
+** too high for restricted hardware.
+** The test file 'cstack.lua' may help finding a good limit.
+** (It will crash with a limit too high.)
+*/
+#if !defined(LUAI_MAXCSTACK)
+#define LUAI_MAXCSTACK		2000
+#endif
+
+
+/*
+@@ LUA_USE_C89 controls the use of non-ISO-C89 features.
+** Define it if you want Lua to avoid the use of a few C99 features
+** or Windows-specific features on Windows.
+*/
+/* #define LUA_USE_C89 */
+
+
+/*
+** By default, Lua on Windows use (some) specific Windows features
+*/
+#if !defined(LUA_USE_C89) && defined(_WIN32) && !defined(_WIN32_WCE)
+#define LUA_USE_WINDOWS  /* enable goodies for regular Windows */
+#endif
+
+
+#if defined(LUA_USE_WINDOWS)
+#define LUA_DL_DLL	/* enable support for DLL */
+#define LUA_USE_C89	/* broadly, Windows is C89 */
+#endif
+
+
+#if defined(LUA_USE_LINUX)
+#define LUA_USE_POSIX
+#define LUA_USE_DLOPEN		/* needs an extra library: -ldl */
+#endif
+
+
+#if defined(LUA_USE_MACOSX)
+#define LUA_USE_POSIX
+#define LUA_USE_DLOPEN		/* MacOS does not need -ldl */
+#endif
+
+
+/*
+@@ LUAI_IS32INT is true iff 'int' has (at least) 32 bits.
+*/
+#define LUAI_IS32INT	((UINT_MAX >> 30) >= 3)
+
+/* }================================================================== */
+
+
+
+/*
+** {==================================================================
+** Configuration for Number types.
+** ===================================================================
+*/
+
+/*
+@@ LUA_32BITS enables Lua with 32-bit integers and 32-bit floats.
+*/
+/* #define LUA_32BITS */
+
+
+/*
+@@ LUA_C89_NUMBERS ensures that Lua uses the largest types available for
+** C89 ('long' and 'double'); Windows always has '__int64', so it does
+** not need to use this case.
+*/
+#if defined(LUA_USE_C89) && !defined(LUA_USE_WINDOWS)
+#define LUA_C89_NUMBERS
+#endif
+
+
+/*
+@@ LUA_INT_TYPE defines the type for Lua integers.
+@@ LUA_FLOAT_TYPE defines the type for Lua floats.
+** Lua should work fine with any mix of these options supported
+** by your C compiler. The usual configurations are 64-bit integers
+** and 'double' (the default), 32-bit integers and 'float' (for
+** restricted platforms), and 'long'/'double' (for C compilers not
+** compliant with C99, which may not have support for 'long long').
+*/
+
+/* predefined options for LUA_INT_TYPE */
+#define LUA_INT_INT		1
+#define LUA_INT_LONG		2
+#define LUA_INT_LONGLONG	3
+
+/* predefined options for LUA_FLOAT_TYPE */
+#define LUA_FLOAT_FLOAT		1
+#define LUA_FLOAT_DOUBLE	2
+#define LUA_FLOAT_LONGDOUBLE	3
+
+#if defined(LUA_32BITS)		/* { */
+/*
+** 32-bit integers and 'float'
+*/
+#if LUAI_IS32INT  /* use 'int' if big enough */
+#define LUA_INT_TYPE	LUA_INT_INT
+#else  /* otherwise use 'long' */
+#define LUA_INT_TYPE	LUA_INT_LONG
+#endif
+#define LUA_FLOAT_TYPE	LUA_FLOAT_FLOAT
+
+#elif defined(LUA_C89_NUMBERS)	/* }{ */
+/*
+** largest types available for C89 ('long' and 'double')
+*/
+#define LUA_INT_TYPE	LUA_INT_LONG
+#define LUA_FLOAT_TYPE	LUA_FLOAT_DOUBLE
+
+#endif				/* } */
+
+
+/*
+** default configuration for 64-bit Lua ('long long' and 'double')
+*/
+#if !defined(LUA_INT_TYPE)
+#define LUA_INT_TYPE	LUA_INT_LONGLONG
+#endif
+
+#if !defined(LUA_FLOAT_TYPE)
+#define LUA_FLOAT_TYPE	LUA_FLOAT_DOUBLE
+#endif
+
+/* }================================================================== */
+
+
+
+/*
+** {==================================================================
+** Configuration for Paths.
+** ===================================================================
+*/
+
+/*
+** LUA_PATH_SEP is the character that separates templates in a path.
+** LUA_PATH_MARK is the string that marks the substitution points in a
+** template.
+** LUA_EXEC_DIR in a Windows path is replaced by the executable's
+** directory.
+*/
+#define LUA_PATH_SEP            ";"
+#define LUA_PATH_MARK           "?"
+#define LUA_EXEC_DIR            "!"
+
+
+/*
+@@ LUA_PATH_DEFAULT is the default path that Lua uses to look for
+** Lua libraries.
+@@ LUA_CPATH_DEFAULT is the default path that Lua uses to look for
+** C libraries.
+** CHANGE them if your machine has a non-conventional directory
+** hierarchy or if you want to install your libraries in
+** non-conventional directories.
+*/
+
+#define LUA_VDIR	LUA_VERSION_MAJOR "." LUA_VERSION_MINOR
+#if defined(_WIN32)	/* { */
+/*
+** In Windows, any exclamation mark ('!') in the path is replaced by the
+** path of the directory of the executable file of the current process.
+*/
+#define LUA_LDIR	"!\\lua\\"
+#define LUA_CDIR	"!\\"
+#define LUA_SHRDIR	"!\\..\\share\\lua\\" LUA_VDIR "\\"
+
+#if !defined(LUA_PATH_DEFAULT)
+#define LUA_PATH_DEFAULT  \
+		LUA_LDIR"?.lua;"  LUA_LDIR"?\\init.lua;" \
+		LUA_CDIR"?.lua;"  LUA_CDIR"?\\init.lua;" \
+		LUA_SHRDIR"?.lua;" LUA_SHRDIR"?\\init.lua;" \
+		".\\?.lua;" ".\\?\\init.lua"
+#endif
+
+#if !defined(LUA_CPATH_DEFAULT)
+#define LUA_CPATH_DEFAULT \
+		LUA_CDIR"?.dll;" \
+		LUA_CDIR"..\\lib\\lua\\" LUA_VDIR "\\?.dll;" \
+		LUA_CDIR"loadall.dll;" ".\\?.dll"
+#endif
+
+#else			/* }{ */
+
+#define LUA_ROOT	"/usr/local/"
+#define LUA_LDIR	LUA_ROOT "share/lua/" LUA_VDIR "/"
+#define LUA_CDIR	LUA_ROOT "lib/lua/" LUA_VDIR "/"
+
+#if !defined(LUA_PATH_DEFAULT)
+#define LUA_PATH_DEFAULT  \
+		LUA_LDIR"?.lua;"  LUA_LDIR"?/init.lua;" \
+		LUA_CDIR"?.lua;"  LUA_CDIR"?/init.lua;" \
+		"./?.lua;" "./?/init.lua"
+#endif
+
+#if !defined(LUA_CPATH_DEFAULT)
+#define LUA_CPATH_DEFAULT \
+		LUA_CDIR"?.so;" LUA_CDIR"loadall.so;" "./?.so"
+#endif
+
+#endif			/* } */
+
+
+/*
+@@ LUA_DIRSEP is the directory separator (for submodules).
+** CHANGE it if your machine does not use "/" as the directory separator
+** and is not Windows. (On Windows Lua automatically uses "\".)
+*/
+#if !defined(LUA_DIRSEP)
+
+#if defined(_WIN32)
+#define LUA_DIRSEP	"\\"
+#else
+#define LUA_DIRSEP	"/"
+#endif
+
+#endif
+
+/* }================================================================== */
+
+
+/*
+** {==================================================================
+** Marks for exported symbols in the C code
+** ===================================================================
+*/
+
+/*
+@@ LUA_API is a mark for all core API functions.
+@@ LUALIB_API is a mark for all auxiliary library functions.
+@@ LUAMOD_API is a mark for all standard library opening functions.
+** CHANGE them if you need to define those functions in some special way.
+** For instance, if you want to create one Windows DLL with the core and
+** the libraries, you may want to use the following definition (define
+** LUA_BUILD_AS_DLL to get it).
+*/
+#if defined(LUA_BUILD_AS_DLL)	/* { */
+
+#if defined(LUA_CORE) || defined(LUA_LIB)	/* { */
+#define LUA_API __declspec(dllexport)
+#else						/* }{ */
+#define LUA_API __declspec(dllimport)
+#endif						/* } */
+
+#else				/* }{ */
+
+#define LUA_API		extern
+
+#endif				/* } */
+
+
+/*
+** More often than not the libs go together with the core.
+*/
+#define LUALIB_API	LUA_API
+#define LUAMOD_API	LUA_API
+
+
+/*
+@@ LUAI_FUNC is a mark for all extern functions that are not to be
+** exported to outside modules.
+@@ LUAI_DDEF and LUAI_DDEC are marks for all extern (const) variables,
+** none of which to be exported to outside modules (LUAI_DDEF for
+** definitions and LUAI_DDEC for declarations).
+** CHANGE them if you need to mark them in some special way. Elf/gcc
+** (versions 3.2 and later) mark them as "hidden" to optimize access
+** when Lua is compiled as a shared library. Not all elf targets support
+** this attribute. Unfortunately, gcc does not offer a way to check
+** whether the target offers that support, and those without support
+** give a warning about it. To avoid these warnings, change to the
+** default definition.
+*/
+#if defined(__GNUC__) && ((__GNUC__*100 + __GNUC_MINOR__) >= 302) && \
+    defined(__ELF__)		/* { */
+#define LUAI_FUNC	__attribute__((visibility("internal"))) extern
+#else				/* }{ */
+#define LUAI_FUNC	extern
+#endif				/* } */
+
+#define LUAI_DDEC(dec)	LUAI_FUNC dec
+#define LUAI_DDEF	/* empty */
+
+/* }================================================================== */
+
+
+/*
+** {==================================================================
+** Compatibility with previous versions
+** ===================================================================
+*/
+
+/*
+@@ LUA_COMPAT_5_3 controls other macros for compatibility with Lua 5.3.
+** You can define it to get all options, or change specific options
+** to fit your specific needs.
+*/
+#if defined(LUA_COMPAT_5_3)	/* { */
+
+/*
+@@ LUA_COMPAT_MATHLIB controls the presence of several deprecated
+** functions in the mathematical library.
+** (These functions were already officially removed in 5.3;
+** nevertheless they are still available here.)
+*/
+#define LUA_COMPAT_MATHLIB
+
+/*
+@@ LUA_COMPAT_APIINTCASTS controls the presence of macros for
+** manipulating other integer types (lua_pushunsigned, lua_tounsigned,
+** luaL_checkint, luaL_checklong, etc.)
+** (These macros were also officially removed in 5.3, but they are still
+** available here.)
+*/
+#define LUA_COMPAT_APIINTCASTS
+
+
+/*
+@@ LUA_COMPAT_LT_LE controls the emulation of the '__le' metamethod
+** using '__lt'.
+*/
+#define LUA_COMPAT_LT_LE
+
+
+/*
+@@ The following macros supply trivial compatibility for some
+** changes in the API. The macros themselves document how to
+** change your code to avoid using them.
+** (Once more, these macros were officially removed in 5.3, but they are
+** still available here.)
+*/
+#define lua_strlen(L,i)		lua_rawlen(L, (i))
+
+#define lua_objlen(L,i)		lua_rawlen(L, (i))
+
+#define lua_equal(L,idx1,idx2)		lua_compare(L,(idx1),(idx2),LUA_OPEQ)
+#define lua_lessthan(L,idx1,idx2)	lua_compare(L,(idx1),(idx2),LUA_OPLT)
+
+#endif				/* } */
+
+/* }================================================================== */
+
+
+
+/*
+** {==================================================================
+** Configuration for Numbers.
+** Change these definitions if no predefined LUA_FLOAT_* / LUA_INT_*
+** satisfy your needs.
+** ===================================================================
+*/
+
+/*
+@@ LUA_NUMBER is the floating-point type used by Lua.
+@@ LUAI_UACNUMBER is the result of a 'default argument promotion'
+@@ over a floating number.
+@@ l_floatatt(x) corrects float attribute 'x' to the proper float type
+** by prefixing it with one of FLT/DBL/LDBL.
+@@ LUA_NUMBER_FRMLEN is the length modifier for writing floats.
+@@ LUA_NUMBER_FMT is the format for writing floats.
+@@ lua_number2str converts a float to a string.
+@@ l_mathop allows the addition of an 'l' or 'f' to all math operations.
+@@ l_floor takes the floor of a float.
+@@ lua_str2number converts a decimal numeral to a number.
+*/
+
+
+/* The following definitions are good for most cases here */
+
+#define l_floor(x)		(l_mathop(floor)(x))
+
+#define lua_number2str(s,sz,n)  \
+	l_sprintf((s), sz, LUA_NUMBER_FMT, (LUAI_UACNUMBER)(n))
+
+/*
+@@ lua_numbertointeger converts a float number with an integral value
+** to an integer, or returns 0 if float is not within the range of
+** a lua_Integer.  (The range comparisons are tricky because of
+** rounding. The tests here assume a two-complement representation,
+** where MININTEGER always has an exact representation as a float;
+** MAXINTEGER may not have one, and therefore its conversion to float
+** may have an ill-defined value.)
+*/
+#define lua_numbertointeger(n,p) \
+  ((n) >= (LUA_NUMBER)(LUA_MININTEGER) && \
+   (n) < -(LUA_NUMBER)(LUA_MININTEGER) && \
+      (*(p) = (LUA_INTEGER)(n), 1))
+
+
+/* now the variable definitions */
+
+#if LUA_FLOAT_TYPE == LUA_FLOAT_FLOAT		/* { single float */
+
+#define LUA_NUMBER	float
+
+#define l_floatatt(n)		(FLT_##n)
+
+#define LUAI_UACNUMBER	double
+
+#define LUA_NUMBER_FRMLEN	""
+#define LUA_NUMBER_FMT		"%.7g"
+
+#define l_mathop(op)		op##f
+
+#define lua_str2number(s,p)	strtof((s), (p))
+
+
+#elif LUA_FLOAT_TYPE == LUA_FLOAT_LONGDOUBLE	/* }{ long double */
+
+#define LUA_NUMBER	long double
+
+#define l_floatatt(n)		(LDBL_##n)
+
+#define LUAI_UACNUMBER	long double
+
+#define LUA_NUMBER_FRMLEN	"L"
+#define LUA_NUMBER_FMT		"%.19Lg"
+
+#define l_mathop(op)		op##l
+
+#define lua_str2number(s,p)	strtold((s), (p))
+
+#elif LUA_FLOAT_TYPE == LUA_FLOAT_DOUBLE	/* }{ double */
+
+#define LUA_NUMBER	double
+
+#define l_floatatt(n)		(DBL_##n)
+
+#define LUAI_UACNUMBER	double
+
+#define LUA_NUMBER_FRMLEN	""
+#define LUA_NUMBER_FMT		"%.14g"
+
+#define l_mathop(op)		op
+
+#define lua_str2number(s,p)	strtod((s), (p))
+
+#else						/* }{ */
+
+#error "numeric float type not defined"
+
+#endif					/* } */
+
+
+
+/*
+@@ LUA_INTEGER is the integer type used by Lua.
+**
+@@ LUA_UNSIGNED is the unsigned version of LUA_INTEGER.
+**
+@@ LUAI_UACINT is the result of a 'default argument promotion'
+@@ over a LUA_INTEGER.
+@@ LUA_INTEGER_FRMLEN is the length modifier for reading/writing integers.
+@@ LUA_INTEGER_FMT is the format for writing integers.
+@@ LUA_MAXINTEGER is the maximum value for a LUA_INTEGER.
+@@ LUA_MININTEGER is the minimum value for a LUA_INTEGER.
+@@ LUA_MAXUNSIGNED is the maximum value for a LUA_UNSIGNED.
+@@ LUA_UNSIGNEDBITS is the number of bits in a LUA_UNSIGNED.
+@@ lua_integer2str converts an integer to a string.
+*/
+
+
+/* The following definitions are good for most cases here */
+
+#define LUA_INTEGER_FMT		"%" LUA_INTEGER_FRMLEN "d"
+
+#define LUAI_UACINT		LUA_INTEGER
+
+#define lua_integer2str(s,sz,n)  \
+	l_sprintf((s), sz, LUA_INTEGER_FMT, (LUAI_UACINT)(n))
+
+/*
+** use LUAI_UACINT here to avoid problems with promotions (which
+** can turn a comparison between unsigneds into a signed comparison)
+*/
+#define LUA_UNSIGNED		unsigned LUAI_UACINT
+
+
+#define LUA_UNSIGNEDBITS	(sizeof(LUA_UNSIGNED) * CHAR_BIT)
+
+
+/* now the variable definitions */
+
+#if LUA_INT_TYPE == LUA_INT_INT		/* { int */
+
+#define LUA_INTEGER		int
+#define LUA_INTEGER_FRMLEN	""
+
+#define LUA_MAXINTEGER		INT_MAX
+#define LUA_MININTEGER		INT_MIN
+
+#define LUA_MAXUNSIGNED		UINT_MAX
+
+#elif LUA_INT_TYPE == LUA_INT_LONG	/* }{ long */
+
+#define LUA_INTEGER		long
+#define LUA_INTEGER_FRMLEN	"l"
+
+#define LUA_MAXINTEGER		LONG_MAX
+#define LUA_MININTEGER		LONG_MIN
+
+#define LUA_MAXUNSIGNED		ULONG_MAX
+
+#elif LUA_INT_TYPE == LUA_INT_LONGLONG	/* }{ long long */
+
+/* use presence of macro LLONG_MAX as proxy for C99 compliance */
+#if defined(LLONG_MAX)		/* { */
+/* use ISO C99 stuff */
+
+#define LUA_INTEGER		long long
+#define LUA_INTEGER_FRMLEN	"ll"
+
+#define LUA_MAXINTEGER		LLONG_MAX
+#define LUA_MININTEGER		LLONG_MIN
+
+#define LUA_MAXUNSIGNED		ULLONG_MAX
+
+#elif defined(LUA_USE_WINDOWS) /* }{ */
+/* in Windows, can use specific Windows types */
+
+#define LUA_INTEGER		__int64
+#define LUA_INTEGER_FRMLEN	"I64"
+
+#define LUA_MAXINTEGER		_I64_MAX
+#define LUA_MININTEGER		_I64_MIN
+
+#define LUA_MAXUNSIGNED		_UI64_MAX
+
+#else				/* }{ */
+
+#error "Compiler does not support 'long long'. Use option '-DLUA_32BITS' \
+  or '-DLUA_C89_NUMBERS' (see file 'luaconf.h' for details)"
+
+#endif				/* } */
+
+#else				/* }{ */
+
+#error "numeric integer type not defined"
+
+#endif				/* } */
+
+/* }================================================================== */
+
+
+/*
+** {==================================================================
+** Dependencies with C99 and other C details
+** ===================================================================
+*/
+
+/*
+@@ l_sprintf is equivalent to 'snprintf' or 'sprintf' in C89.
+** (All uses in Lua have only one format item.)
+*/
+#if !defined(LUA_USE_C89)
+#define l_sprintf(s,sz,f,i)	snprintf(s,sz,f,i)
+#else
+#define l_sprintf(s,sz,f,i)	((void)(sz), sprintf(s,f,i))
+#endif
+
+
+/*
+@@ lua_strx2number converts a hexadecimal numeral to a number.
+** In C99, 'strtod' does that conversion. Otherwise, you can
+** leave 'lua_strx2number' undefined and Lua will provide its own
+** implementation.
+*/
+#if !defined(LUA_USE_C89)
+#define lua_strx2number(s,p)		lua_str2number(s,p)
+#endif
+
+
+/*
+@@ lua_pointer2str converts a pointer to a readable string in a
+** non-specified way.
+*/
+#define lua_pointer2str(buff,sz,p)	l_sprintf(buff,sz,"%p",p)
+
+
+/*
+@@ lua_number2strx converts a float to a hexadecimal numeral.
+** In C99, 'sprintf' (with format specifiers '%a'/'%A') does that.
+** Otherwise, you can leave 'lua_number2strx' undefined and Lua will
+** provide its own implementation.
+*/
+#if !defined(LUA_USE_C89)
+#define lua_number2strx(L,b,sz,f,n)  \
+	((void)L, l_sprintf(b,sz,f,(LUAI_UACNUMBER)(n)))
+#endif
+
+
+/*
+** 'strtof' and 'opf' variants for math functions are not valid in
+** C89. Otherwise, the macro 'HUGE_VALF' is a good proxy for testing the
+** availability of these variants. ('math.h' is already included in
+** all files that use these macros.)
+*/
+#if defined(LUA_USE_C89) || (defined(HUGE_VAL) && !defined(HUGE_VALF))
+#undef l_mathop  /* variants not available */
+#undef lua_str2number
+#define l_mathop(op)		(lua_Number)op  /* no variant */
+#define lua_str2number(s,p)	((lua_Number)strtod((s), (p)))
+#endif
+
+
+/*
+@@ LUA_KCONTEXT is the type of the context ('ctx') for continuation
+** functions.  It must be a numerical type; Lua will use 'intptr_t' if
+** available, otherwise it will use 'ptrdiff_t' (the nearest thing to
+** 'intptr_t' in C89)
+*/
+#define LUA_KCONTEXT	ptrdiff_t
+
+#if !defined(LUA_USE_C89) && defined(__STDC_VERSION__) && \
+    __STDC_VERSION__ >= 199901L
+#include <stdint.h>
+#if defined(INTPTR_MAX)  /* even in C99 this type is optional */
+#undef LUA_KCONTEXT
+#define LUA_KCONTEXT	intptr_t
+#endif
+#endif
+
+
+/*
+@@ lua_getlocaledecpoint gets the locale "radix character" (decimal point).
+** Change that if you do not want to use C locales. (Code using this
+** macro must include the header 'locale.h'.)
+*/
+#if !defined(lua_getlocaledecpoint)
+#define lua_getlocaledecpoint()		(localeconv()->decimal_point[0])
+#endif
+
+/* }================================================================== */
+
+
+/*
+** {==================================================================
+** Language Variations
+** =====================================================================
+*/
+
+/*
+@@ LUA_NOCVTN2S/LUA_NOCVTS2N control how Lua performs some
+** coercions. Define LUA_NOCVTN2S to turn off automatic coercion from
+** numbers to strings. Define LUA_NOCVTS2N to turn off automatic
+** coercion from strings to numbers.
+*/
+/* #define LUA_NOCVTN2S */
+/* #define LUA_NOCVTS2N */
+
+
+/*
+@@ LUA_USE_APICHECK turns on several consistency checks on the C API.
+** Define it as a help when debugging C code.
+*/
+#if defined(LUA_USE_APICHECK)
+#include <assert.h>
+#define luai_apicheck(l,e)	assert(e)
+#endif
+
+/* }================================================================== */
+
+
+/*
+** {==================================================================
+** Macros that affect the API and must be stable (that is, must be the
+** same when you compile Lua and when you compile code that links to
+** Lua).
+** =====================================================================
+*/
+
+/*
+@@ LUAI_MAXSTACK limits the size of the Lua stack.
+** CHANGE it if you need a different limit. This limit is arbitrary;
+** its only purpose is to stop Lua from consuming unlimited stack
+** space (and to reserve some numbers for pseudo-indices).
+** (It must fit into max(size_t)/32.)
+*/
+#if LUAI_IS32INT
+#define LUAI_MAXSTACK		1000000
+#else
+#define LUAI_MAXSTACK		15000
+#endif
+
+
+/*
+@@ LUA_EXTRASPACE defines the size of a raw memory area associated with
+** a Lua state with very fast access.
+** CHANGE it if you need a different size.
+*/
+#define LUA_EXTRASPACE		(sizeof(void *))
+
+
+/*
+@@ LUA_IDSIZE gives the maximum size for the description of the source
+@@ of a function in debug information.
+** CHANGE it if you want a different size.
+*/
+#define LUA_IDSIZE	60
+
+
+/*
+@@ LUAL_BUFFERSIZE is the buffer size used by the lauxlib buffer system.
+*/
+#define LUAL_BUFFERSIZE   ((int)(16 * sizeof(void*) * sizeof(lua_Number)))
+
+
+/*
+@@ LUAI_MAXALIGN defines fields that, when used in a union, ensure
+** maximum alignment for the other items in that union.
+*/
+#define LUAI_MAXALIGN  lua_Number n; double u; void *s; lua_Integer i; long l
+
+/* }================================================================== */
+
+
+
+
+
+/* =================================================================== */
+
+/*
+** Local configuration. You can use this space to add your redefinitions
+** without modifying the main part of the file.
+*/
+
+
+
+
+
+#endif
+
diff --git a/test/external/lua-5.4.0/src/lualib.h b/test/external/lua-5.4.0/src/lualib.h
new file mode 100644
index 0000000..eb08b53
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lualib.h
@@ -0,0 +1,58 @@
+/*
+** $Id: lualib.h $
+** Lua standard libraries
+** See Copyright Notice in lua.h
+*/
+
+
+#ifndef lualib_h
+#define lualib_h
+
+#include "lua.h"
+
+
+/* version suffix for environment variable names */
+#define LUA_VERSUFFIX          "_" LUA_VERSION_MAJOR "_" LUA_VERSION_MINOR
+
+
+LUAMOD_API int (luaopen_base) (lua_State *L);
+
+#define LUA_COLIBNAME	"coroutine"
+LUAMOD_API int (luaopen_coroutine) (lua_State *L);
+
+#define LUA_TABLIBNAME	"table"
+LUAMOD_API int (luaopen_table) (lua_State *L);
+
+#define LUA_IOLIBNAME	"io"
+LUAMOD_API int (luaopen_io) (lua_State *L);
+
+#define LUA_OSLIBNAME	"os"
+LUAMOD_API int (luaopen_os) (lua_State *L);
+
+#define LUA_STRLIBNAME	"string"
+LUAMOD_API int (luaopen_string) (lua_State *L);
+
+#define LUA_UTF8LIBNAME	"utf8"
+LUAMOD_API int (luaopen_utf8) (lua_State *L);
+
+#define LUA_MATHLIBNAME	"math"
+LUAMOD_API int (luaopen_math) (lua_State *L);
+
+#define LUA_DBLIBNAME	"debug"
+LUAMOD_API int (luaopen_debug) (lua_State *L);
+
+#define LUA_LOADLIBNAME	"package"
+LUAMOD_API int (luaopen_package) (lua_State *L);
+
+
+/* open all previous libraries */
+LUALIB_API void (luaL_openlibs) (lua_State *L);
+
+
+
+#if !defined(lua_assert)
+#define lua_assert(x)	((void)0)
+#endif
+
+
+#endif
diff --git a/test/external/lua-5.4.0/src/lundump.c b/test/external/lua-5.4.0/src/lundump.c
new file mode 100644
index 0000000..4243678
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lundump.c
@@ -0,0 +1,323 @@
+/*
+** $Id: lundump.c $
+** load precompiled Lua chunks
+** See Copyright Notice in lua.h
+*/
+
+#define lundump_c
+#define LUA_CORE
+
+#include "lprefix.h"
+
+
+#include <limits.h>
+#include <string.h>
+
+#include "lua.h"
+
+#include "ldebug.h"
+#include "ldo.h"
+#include "lfunc.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lstring.h"
+#include "lundump.h"
+#include "lzio.h"
+
+
+#if !defined(luai_verifycode)
+#define luai_verifycode(L,f)  /* empty */
+#endif
+
+
+typedef struct {
+  lua_State *L;
+  ZIO *Z;
+  const char *name;
+} LoadState;
+
+
+static l_noret error (LoadState *S, const char *why) {
+  luaO_pushfstring(S->L, "%s: bad binary format (%s)", S->name, why);
+  luaD_throw(S->L, LUA_ERRSYNTAX);
+}
+
+
+/*
+** All high-level loads go through loadVector; you can change it to
+** adapt to the endianness of the input
+*/
+#define loadVector(S,b,n)	loadBlock(S,b,(n)*sizeof((b)[0]))
+
+static void loadBlock (LoadState *S, void *b, size_t size) {
+  if (luaZ_read(S->Z, b, size) != 0)
+    error(S, "truncated chunk");
+}
+
+
+#define loadVar(S,x)		loadVector(S,&x,1)
+
+
+static lu_byte loadByte (LoadState *S) {
+  int b = zgetc(S->Z);
+  if (b == EOZ)
+    error(S, "truncated chunk");
+  return cast_byte(b);
+}
+
+
+static size_t loadUnsigned (LoadState *S, size_t limit) {
+  size_t x = 0;
+  int b;
+  limit >>= 7;
+  do {
+    b = loadByte(S);
+    if (x >= limit)
+      error(S, "integer overflow");
+    x = (x << 7) | (b & 0x7f);
+  } while ((b & 0x80) == 0);
+  return x;
+}
+
+
+static size_t loadSize (LoadState *S) {
+  return loadUnsigned(S, ~(size_t)0);
+}
+
+
+static int loadInt (LoadState *S) {
+  return cast_int(loadUnsigned(S, INT_MAX));
+}
+
+
+static lua_Number loadNumber (LoadState *S) {
+  lua_Number x;
+  loadVar(S, x);
+  return x;
+}
+
+
+static lua_Integer loadInteger (LoadState *S) {
+  lua_Integer x;
+  loadVar(S, x);
+  return x;
+}
+
+
+/*
+** Load a nullable string into prototype 'p'.
+*/
+static TString *loadStringN (LoadState *S, Proto *p) {
+  lua_State *L = S->L;
+  TString *ts;
+  size_t size = loadSize(S);
+  if (size == 0)  /* no string? */
+    return NULL;
+  else if (--size <= LUAI_MAXSHORTLEN) {  /* short string? */
+    char buff[LUAI_MAXSHORTLEN];
+    loadVector(S, buff, size);  /* load string into buffer */
+    ts = luaS_newlstr(L, buff, size);  /* create string */
+  }
+  else {  /* long string */
+    ts = luaS_createlngstrobj(L, size);  /* create string */
+    loadVector(S, getstr(ts), size);  /* load directly in final place */
+  }
+  luaC_objbarrier(L, p, ts);
+  return ts;
+}
+
+
+/*
+** Load a non-nullable string into prototype 'p'.
+*/
+static TString *loadString (LoadState *S, Proto *p) {
+  TString *st = loadStringN(S, p);
+  if (st == NULL)
+    error(S, "bad format for constant string");
+  return st;
+}
+
+
+static void loadCode (LoadState *S, Proto *f) {
+  int n = loadInt(S);
+  f->code = luaM_newvectorchecked(S->L, n, Instruction);
+  f->sizecode = n;
+  loadVector(S, f->code, n);
+}
+
+
+static void loadFunction(LoadState *S, Proto *f, TString *psource);
+
+
+static void loadConstants (LoadState *S, Proto *f) {
+  int i;
+  int n = loadInt(S);
+  f->k = luaM_newvectorchecked(S->L, n, TValue);
+  f->sizek = n;
+  for (i = 0; i < n; i++)
+    setnilvalue(&f->k[i]);
+  for (i = 0; i < n; i++) {
+    TValue *o = &f->k[i];
+    int t = loadByte(S);
+    switch (t) {
+      case LUA_VNIL:
+        setnilvalue(o);
+        break;
+      case LUA_VFALSE:
+        setbfvalue(o);
+        break;
+      case LUA_VTRUE:
+        setbtvalue(o);
+        break;
+      case LUA_VNUMFLT:
+        setfltvalue(o, loadNumber(S));
+        break;
+      case LUA_VNUMINT:
+        setivalue(o, loadInteger(S));
+        break;
+      case LUA_VSHRSTR:
+      case LUA_VLNGSTR:
+        setsvalue2n(S->L, o, loadString(S, f));
+        break;
+      default: lua_assert(0);
+    }
+  }
+}
+
+
+static void loadProtos (LoadState *S, Proto *f) {
+  int i;
+  int n = loadInt(S);
+  f->p = luaM_newvectorchecked(S->L, n, Proto *);
+  f->sizep = n;
+  for (i = 0; i < n; i++)
+    f->p[i] = NULL;
+  for (i = 0; i < n; i++) {
+    f->p[i] = luaF_newproto(S->L);
+    luaC_objbarrier(S->L, f, f->p[i]);
+    loadFunction(S, f->p[i], f->source);
+  }
+}
+
+
+static void loadUpvalues (LoadState *S, Proto *f) {
+  int i, n;
+  n = loadInt(S);
+  f->upvalues = luaM_newvectorchecked(S->L, n, Upvaldesc);
+  f->sizeupvalues = n;
+  for (i = 0; i < n; i++) {
+    f->upvalues[i].name = NULL;
+    f->upvalues[i].instack = loadByte(S);
+    f->upvalues[i].idx = loadByte(S);
+    f->upvalues[i].kind = loadByte(S);
+  }
+}
+
+
+static void loadDebug (LoadState *S, Proto *f) {
+  int i, n;
+  n = loadInt(S);
+  f->lineinfo = luaM_newvectorchecked(S->L, n, ls_byte);
+  f->sizelineinfo = n;
+  loadVector(S, f->lineinfo, n);
+  n = loadInt(S);
+  f->abslineinfo = luaM_newvectorchecked(S->L, n, AbsLineInfo);
+  f->sizeabslineinfo = n;
+  for (i = 0; i < n; i++) {
+    f->abslineinfo[i].pc = loadInt(S);
+    f->abslineinfo[i].line = loadInt(S);
+  }
+  n = loadInt(S);
+  f->locvars = luaM_newvectorchecked(S->L, n, LocVar);
+  f->sizelocvars = n;
+  for (i = 0; i < n; i++)
+    f->locvars[i].varname = NULL;
+  for (i = 0; i < n; i++) {
+    f->locvars[i].varname = loadStringN(S, f);
+    f->locvars[i].startpc = loadInt(S);
+    f->locvars[i].endpc = loadInt(S);
+  }
+  n = loadInt(S);
+  for (i = 0; i < n; i++)
+    f->upvalues[i].name = loadStringN(S, f);
+}
+
+
+static void loadFunction (LoadState *S, Proto *f, TString *psource) {
+  f->source = loadStringN(S, f);
+  if (f->source == NULL)  /* no source in dump? */
+    f->source = psource;  /* reuse parent's source */
+  f->linedefined = loadInt(S);
+  f->lastlinedefined = loadInt(S);
+  f->numparams = loadByte(S);
+  f->is_vararg = loadByte(S);
+  f->maxstacksize = loadByte(S);
+  loadCode(S, f);
+  loadConstants(S, f);
+  loadUpvalues(S, f);
+  loadProtos(S, f);
+  loadDebug(S, f);
+}
+
+
+static void checkliteral (LoadState *S, const char *s, const char *msg) {
+  char buff[sizeof(LUA_SIGNATURE) + sizeof(LUAC_DATA)]; /* larger than both */
+  size_t len = strlen(s);
+  loadVector(S, buff, len);
+  if (memcmp(s, buff, len) != 0)
+    error(S, msg);
+}
+
+
+static void fchecksize (LoadState *S, size_t size, const char *tname) {
+  if (loadByte(S) != size)
+    error(S, luaO_pushfstring(S->L, "%s size mismatch", tname));
+}
+
+
+#define checksize(S,t)	fchecksize(S,sizeof(t),#t)
+
+static void checkHeader (LoadState *S) {
+  /* skip 1st char (already read and checked) */
+  checkliteral(S, &LUA_SIGNATURE[1], "not a binary chunk");
+  if (loadByte(S) != LUAC_VERSION)
+    error(S, "version mismatch");
+  if (loadByte(S) != LUAC_FORMAT)
+    error(S, "format mismatch");
+  checkliteral(S, LUAC_DATA, "corrupted chunk");
+  checksize(S, Instruction);
+  checksize(S, lua_Integer);
+  checksize(S, lua_Number);
+  if (loadInteger(S) != LUAC_INT)
+    error(S, "integer format mismatch");
+  if (loadNumber(S) != LUAC_NUM)
+    error(S, "float format mismatch");
+}
+
+
+/*
+** Load precompiled chunk.
+*/
+LClosure *luaU_undump(lua_State *L, ZIO *Z, const char *name) {
+  LoadState S;
+  LClosure *cl;
+  if (*name == '@' || *name == '=')
+    S.name = name + 1;
+  else if (*name == LUA_SIGNATURE[0])
+    S.name = "binary string";
+  else
+    S.name = name;
+  S.L = L;
+  S.Z = Z;
+  checkHeader(&S);
+  cl = luaF_newLclosure(L, loadByte(&S));
+  setclLvalue2s(L, L->top, cl);
+  luaD_inctop(L);
+  cl->p = luaF_newproto(L);
+  luaC_objbarrier(L, cl, cl->p);
+  loadFunction(&S, cl->p, NULL);
+  lua_assert(cl->nupvalues == cl->p->sizeupvalues);
+  luai_verifycode(L, cl->p);
+  return cl;
+}
+
diff --git a/test/external/lua-5.4.0/src/lundump.h b/test/external/lua-5.4.0/src/lundump.h
new file mode 100644
index 0000000..f3748a9
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lundump.h
@@ -0,0 +1,36 @@
+/*
+** $Id: lundump.h $
+** load precompiled Lua chunks
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lundump_h
+#define lundump_h
+
+#include "llimits.h"
+#include "lobject.h"
+#include "lzio.h"
+
+
+/* data to catch conversion errors */
+#define LUAC_DATA	"\x19\x93\r\n\x1a\n"
+
+#define LUAC_INT	0x5678
+#define LUAC_NUM	cast_num(370.5)
+
+/*
+** Encode major-minor version in one byte, one nibble for each
+*/
+#define MYINT(s)	(s[0]-'0')  /* assume one-digit numerals */
+#define LUAC_VERSION	(MYINT(LUA_VERSION_MAJOR)*16+MYINT(LUA_VERSION_MINOR))
+
+#define LUAC_FORMAT	0	/* this is the official format */
+
+/* load one chunk; from lundump.c */
+LUAI_FUNC LClosure* luaU_undump (lua_State* L, ZIO* Z, const char* name);
+
+/* dump one chunk; from ldump.c */
+LUAI_FUNC int luaU_dump (lua_State* L, const Proto* f, lua_Writer w,
+                         void* data, int strip);
+
+#endif
diff --git a/test/external/lua-5.4.0/src/lutf8lib.c b/test/external/lua-5.4.0/src/lutf8lib.c
new file mode 100644
index 0000000..901d985
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lutf8lib.c
@@ -0,0 +1,289 @@
+/*
+** $Id: lutf8lib.c $
+** Standard library for UTF-8 manipulation
+** See Copyright Notice in lua.h
+*/
+
+#define lutf8lib_c
+#define LUA_LIB
+
+#include "lprefix.h"
+
+
+#include <assert.h>
+#include <limits.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+#define MAXUNICODE	0x10FFFFu
+
+#define MAXUTF		0x7FFFFFFFu
+
+/*
+** Integer type for decoded UTF-8 values; MAXUTF needs 31 bits.
+*/
+#if (UINT_MAX >> 30) >= 1
+typedef unsigned int utfint;
+#else
+typedef unsigned long utfint;
+#endif
+
+
+#define iscont(p)	((*(p) & 0xC0) == 0x80)
+
+
+/* from strlib */
+/* translate a relative string position: negative means back from end */
+static lua_Integer u_posrelat (lua_Integer pos, size_t len) {
+  if (pos >= 0) return pos;
+  else if (0u - (size_t)pos > len) return 0;
+  else return (lua_Integer)len + pos + 1;
+}
+
+
+/*
+** Decode one UTF-8 sequence, returning NULL if byte sequence is
+** invalid.  The array 'limits' stores the minimum value for each
+** sequence length, to check for overlong representations. Its first
+** entry forces an error for non-ascii bytes with no continuation
+** bytes (count == 0).
+*/
+static const char *utf8_decode (const char *s, utfint *val, int strict) {
+  static const utfint limits[] =
+        {~(utfint)0, 0x80, 0x800, 0x10000u, 0x200000u, 0x4000000u};
+  unsigned int c = (unsigned char)s[0];
+  utfint res = 0;  /* final result */
+  if (c < 0x80)  /* ascii? */
+    res = c;
+  else {
+    int count = 0;  /* to count number of continuation bytes */
+    for (; c & 0x40; c <<= 1) {  /* while it needs continuation bytes... */
+      unsigned int cc = (unsigned char)s[++count];  /* read next byte */
+      if ((cc & 0xC0) != 0x80)  /* not a continuation byte? */
+        return NULL;  /* invalid byte sequence */
+      res = (res << 6) | (cc & 0x3F);  /* add lower 6 bits from cont. byte */
+    }
+    res |= ((utfint)(c & 0x7F) << (count * 5));  /* add first byte */
+    if (count > 5 || res > MAXUTF || res < limits[count])
+      return NULL;  /* invalid byte sequence */
+    s += count;  /* skip continuation bytes read */
+  }
+  if (strict) {
+    /* check for invalid code points; too large or surrogates */
+    if (res > MAXUNICODE || (0xD800u <= res && res <= 0xDFFFu))
+      return NULL;
+  }
+  if (val) *val = res;
+  return s + 1;  /* +1 to include first byte */
+}
+
+
+/*
+** utf8len(s [, i [, j [, lax]]]) --> number of characters that
+** start in the range [i,j], or nil + current position if 's' is not
+** well formed in that interval
+*/
+static int utflen (lua_State *L) {
+  lua_Integer n = 0;  /* counter for the number of characters */
+  size_t len;  /* string length in bytes */
+  const char *s = luaL_checklstring(L, 1, &len);
+  lua_Integer posi = u_posrelat(luaL_optinteger(L, 2, 1), len);
+  lua_Integer posj = u_posrelat(luaL_optinteger(L, 3, -1), len);
+  int lax = lua_toboolean(L, 4);
+  luaL_argcheck(L, 1 <= posi && --posi <= (lua_Integer)len, 2,
+                   "initial position out of bounds");
+  luaL_argcheck(L, --posj < (lua_Integer)len, 3,
+                   "final position out of bounds");
+  while (posi <= posj) {
+    const char *s1 = utf8_decode(s + posi, NULL, !lax);
+    if (s1 == NULL) {  /* conversion error? */
+      luaL_pushfail(L);  /* return fail ... */
+      lua_pushinteger(L, posi + 1);  /* ... and current position */
+      return 2;
+    }
+    posi = s1 - s;
+    n++;
+  }
+  lua_pushinteger(L, n);
+  return 1;
+}
+
+
+/*
+** codepoint(s, [i, [j [, lax]]]) -> returns codepoints for all
+** characters that start in the range [i,j]
+*/
+static int codepoint (lua_State *L) {
+  size_t len;
+  const char *s = luaL_checklstring(L, 1, &len);
+  lua_Integer posi = u_posrelat(luaL_optinteger(L, 2, 1), len);
+  lua_Integer pose = u_posrelat(luaL_optinteger(L, 3, posi), len);
+  int lax = lua_toboolean(L, 4);
+  int n;
+  const char *se;
+  luaL_argcheck(L, posi >= 1, 2, "out of bounds");
+  luaL_argcheck(L, pose <= (lua_Integer)len, 3, "out of bounds");
+  if (posi > pose) return 0;  /* empty interval; return no values */
+  if (pose - posi >= INT_MAX)  /* (lua_Integer -> int) overflow? */
+    return luaL_error(L, "string slice too long");
+  n = (int)(pose -  posi) + 1;  /* upper bound for number of returns */
+  luaL_checkstack(L, n, "string slice too long");
+  n = 0;  /* count the number of returns */
+  se = s + pose;  /* string end */
+  for (s += posi - 1; s < se;) {
+    utfint code;
+    s = utf8_decode(s, &code, !lax);
+    if (s == NULL)
+      return luaL_error(L, "invalid UTF-8 code");
+    lua_pushinteger(L, code);
+    n++;
+  }
+  return n;
+}
+
+
+static void pushutfchar (lua_State *L, int arg) {
+  lua_Unsigned code = (lua_Unsigned)luaL_checkinteger(L, arg);
+  luaL_argcheck(L, code <= MAXUTF, arg, "value out of range");
+  lua_pushfstring(L, "%U", (long)code);
+}
+
+
+/*
+** utfchar(n1, n2, ...)  -> char(n1)..char(n2)...
+*/
+static int utfchar (lua_State *L) {
+  int n = lua_gettop(L);  /* number of arguments */
+  if (n == 1)  /* optimize common case of single char */
+    pushutfchar(L, 1);
+  else {
+    int i;
+    luaL_Buffer b;
+    luaL_buffinit(L, &b);
+    for (i = 1; i <= n; i++) {
+      pushutfchar(L, i);
+      luaL_addvalue(&b);
+    }
+    luaL_pushresult(&b);
+  }
+  return 1;
+}
+
+
+/*
+** offset(s, n, [i])  -> index where n-th character counting from
+**   position 'i' starts; 0 means character at 'i'.
+*/
+static int byteoffset (lua_State *L) {
+  size_t len;
+  const char *s = luaL_checklstring(L, 1, &len);
+  lua_Integer n  = luaL_checkinteger(L, 2);
+  lua_Integer posi = (n >= 0) ? 1 : len + 1;
+  posi = u_posrelat(luaL_optinteger(L, 3, posi), len);
+  luaL_argcheck(L, 1 <= posi && --posi <= (lua_Integer)len, 3,
+                   "position out of bounds");
+  if (n == 0) {
+    /* find beginning of current byte sequence */
+    while (posi > 0 && iscont(s + posi)) posi--;
+  }
+  else {
+    if (iscont(s + posi))
+      return luaL_error(L, "initial position is a continuation byte");
+    if (n < 0) {
+       while (n < 0 && posi > 0) {  /* move back */
+         do {  /* find beginning of previous character */
+           posi--;
+         } while (posi > 0 && iscont(s + posi));
+         n++;
+       }
+     }
+     else {
+       n--;  /* do not move for 1st character */
+       while (n > 0 && posi < (lua_Integer)len) {
+         do {  /* find beginning of next character */
+           posi++;
+         } while (iscont(s + posi));  /* (cannot pass final '\0') */
+         n--;
+       }
+     }
+  }
+  if (n == 0)  /* did it find given character? */
+    lua_pushinteger(L, posi + 1);
+  else  /* no such character */
+    luaL_pushfail(L);
+  return 1;
+}
+
+
+static int iter_aux (lua_State *L, int strict) {
+  size_t len;
+  const char *s = luaL_checklstring(L, 1, &len);
+  lua_Integer n = lua_tointeger(L, 2) - 1;
+  if (n < 0)  /* first iteration? */
+    n = 0;  /* start from here */
+  else if (n < (lua_Integer)len) {
+    n++;  /* skip current byte */
+    while (iscont(s + n)) n++;  /* and its continuations */
+  }
+  if (n >= (lua_Integer)len)
+    return 0;  /* no more codepoints */
+  else {
+    utfint code;
+    const char *next = utf8_decode(s + n, &code, strict);
+    if (next == NULL)
+      return luaL_error(L, "invalid UTF-8 code");
+    lua_pushinteger(L, n + 1);
+    lua_pushinteger(L, code);
+    return 2;
+  }
+}
+
+
+static int iter_auxstrict (lua_State *L) {
+  return iter_aux(L, 1);
+}
+
+static int iter_auxlax (lua_State *L) {
+  return iter_aux(L, 0);
+}
+
+
+static int iter_codes (lua_State *L) {
+  int lax = lua_toboolean(L, 2);
+  luaL_checkstring(L, 1);
+  lua_pushcfunction(L, lax ? iter_auxlax : iter_auxstrict);
+  lua_pushvalue(L, 1);
+  lua_pushinteger(L, 0);
+  return 3;
+}
+
+
+/* pattern to match a single UTF-8 character */
+#define UTF8PATT	"[\0-\x7F\xC2-\xFD][\x80-\xBF]*"
+
+
+static const luaL_Reg funcs[] = {
+  {"offset", byteoffset},
+  {"codepoint", codepoint},
+  {"char", utfchar},
+  {"len", utflen},
+  {"codes", iter_codes},
+  /* placeholders */
+  {"charpattern", NULL},
+  {NULL, NULL}
+};
+
+
+LUAMOD_API int luaopen_utf8 (lua_State *L) {
+  luaL_newlib(L, funcs);
+  lua_pushlstring(L, UTF8PATT, sizeof(UTF8PATT)/sizeof(char) - 1);
+  lua_setfield(L, -2, "charpattern");
+  return 1;
+}
+
diff --git a/test/external/lua-5.4.0/src/lvm.c b/test/external/lua-5.4.0/src/lvm.c
new file mode 100644
index 0000000..e7781db
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lvm.c
@@ -0,0 +1,1812 @@
+/*
+** $Id: lvm.c $
+** Lua virtual machine
+** See Copyright Notice in lua.h
+*/
+
+#define lvm_c
+#define LUA_CORE
+
+#include "lprefix.h"
+
+#include <float.h>
+#include <limits.h>
+#include <math.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "lua.h"
+
+#include "ldebug.h"
+#include "ldo.h"
+#include "lfunc.h"
+#include "lgc.h"
+#include "lobject.h"
+#include "lopcodes.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "ltm.h"
+#include "lvm.h"
+
+
+/*
+** By default, use jump tables in the main interpreter loop on gcc
+** and compatible compilers.
+*/
+#if !defined(LUA_USE_JUMPTABLE)
+#if defined(__GNUC__)
+#define LUA_USE_JUMPTABLE	1
+#else
+#define LUA_USE_JUMPTABLE	0
+#endif
+#endif
+
+
+
+/* limit for table tag-method chains (to avoid infinite loops) */
+#define MAXTAGLOOP	2000
+
+
+/*
+** 'l_intfitsf' checks whether a given integer is in the range that
+** can be converted to a float without rounding. Used in comparisons.
+*/
+
+/* number of bits in the mantissa of a float */
+#define NBM		(l_floatatt(MANT_DIG))
+
+/*
+** Check whether some integers may not fit in a float, testing whether
+** (maxinteger >> NBM) > 0. (That implies (1 << NBM) <= maxinteger.)
+** (The shifts are done in parts, to avoid shifting by more than the size
+** of an integer. In a worst case, NBM == 113 for long double and
+** sizeof(long) == 32.)
+*/
+#if ((((LUA_MAXINTEGER >> (NBM / 4)) >> (NBM / 4)) >> (NBM / 4)) \
+	>> (NBM - (3 * (NBM / 4))))  >  0
+
+/* limit for integers that fit in a float */
+#define MAXINTFITSF	((lua_Unsigned)1 << NBM)
+
+/* check whether 'i' is in the interval [-MAXINTFITSF, MAXINTFITSF] */
+#define l_intfitsf(i)	((MAXINTFITSF + l_castS2U(i)) <= (2 * MAXINTFITSF))
+
+#else  /* all integers fit in a float precisely */
+
+#define l_intfitsf(i)	1
+
+#endif
+
+
+/*
+** Try to convert a value from string to a number value.
+** If the value is not a string or is a string not representing
+** a valid numeral (or if coercions from strings to numbers
+** are disabled via macro 'cvt2num'), do not modify 'result'
+** and return 0.
+*/
+static int l_strton (const TValue *obj, TValue *result) {
+  lua_assert(obj != result);
+  if (!cvt2num(obj))  /* is object not a string? */
+    return 0;
+  else
+    return (luaO_str2num(svalue(obj), result) == vslen(obj) + 1);
+}
+
+
+/*
+** Try to convert a value to a float. The float case is already handled
+** by the macro 'tonumber'.
+*/
+int luaV_tonumber_ (const TValue *obj, lua_Number *n) {
+  TValue v;
+  if (ttisinteger(obj)) {
+    *n = cast_num(ivalue(obj));
+    return 1;
+  }
+  else if (l_strton(obj, &v)) {  /* string coercible to number? */
+    *n = nvalue(&v);  /* convert result of 'luaO_str2num' to a float */
+    return 1;
+  }
+  else
+    return 0;  /* conversion failed */
+}
+
+
+/*
+** try to convert a float to an integer, rounding according to 'mode'.
+*/
+int luaV_flttointeger (lua_Number n, lua_Integer *p, F2Imod mode) {
+  lua_Number f = l_floor(n);
+  if (n != f) {  /* not an integral value? */
+    if (mode == F2Ieq) return 0;  /* fails if mode demands integral value */
+    else if (mode == F2Iceil)  /* needs ceil? */
+      f += 1;  /* convert floor to ceil (remember: n != f) */
+  }
+  return lua_numbertointeger(f, p);
+}
+
+
+/*
+** try to convert a value to an integer, rounding according to 'mode',
+** without string coercion.
+** ("Fast track" handled by macro 'tointegerns'.)
+*/
+int luaV_tointegerns (const TValue *obj, lua_Integer *p, F2Imod mode) {
+  if (ttisfloat(obj))
+    return luaV_flttointeger(fltvalue(obj), p, mode);
+  else if (ttisinteger(obj)) {
+    *p = ivalue(obj);
+    return 1;
+  }
+  else
+    return 0;
+}
+
+
+/*
+** try to convert a value to an integer.
+*/
+int luaV_tointeger (const TValue *obj, lua_Integer *p, F2Imod mode) {
+  TValue v;
+  if (l_strton(obj, &v))  /* does 'obj' point to a numerical string? */
+    obj = &v;  /* change it to point to its corresponding number */
+  return luaV_tointegerns(obj, p, mode);
+}
+
+
+/*
+** Try to convert a 'for' limit to an integer, preserving the semantics
+** of the loop. Return true if the loop must not run; otherwise, '*p'
+** gets the integer limit.
+** (The following explanation assumes a positive step; it is valid for
+** negative steps mutatis mutandis.)
+** If the limit is an integer or can be converted to an integer,
+** rounding down, that is the limit.
+** Otherwise, check whether the limit can be converted to a float. If
+** the float is too large, clip it to LUA_MAXINTEGER.  If the float
+** is too negative, the loop should not run, because any initial
+** integer value is greater than such limit; so, the function returns
+** true to signal that. (For this latter case, no integer limit would be
+** correct; even a limit of LUA_MININTEGER would run the loop once for
+** an initial value equal to LUA_MININTEGER.)
+*/
+static int forlimit (lua_State *L, lua_Integer init, const TValue *lim,
+                                   lua_Integer *p, lua_Integer step) {
+  if (!luaV_tointeger(lim, p, (step < 0 ? F2Iceil : F2Ifloor))) {
+    /* not coercible to in integer */
+    lua_Number flim;  /* try to convert to float */
+    if (!tonumber(lim, &flim)) /* cannot convert to float? */
+      luaG_forerror(L, lim, "limit");
+    /* else 'flim' is a float out of integer bounds */
+    if (luai_numlt(0, flim)) {  /* if it is positive, it is too large */
+      if (step < 0) return 1;  /* initial value must be less than it */
+      *p = LUA_MAXINTEGER;  /* truncate */
+    }
+    else {  /* it is less than min integer */
+      if (step > 0) return 1;  /* initial value must be greater than it */
+      *p = LUA_MININTEGER;  /* truncate */
+    }
+  }
+  return (step > 0 ? init > *p : init < *p);  /* not to run? */
+}
+
+
+/*
+** Prepare a numerical for loop (opcode OP_FORPREP).
+** Return true to skip the loop. Otherwise,
+** after preparation, stack will be as follows:
+**   ra : internal index (safe copy of the control variable)
+**   ra + 1 : loop counter (integer loops) or limit (float loops)
+**   ra + 2 : step
+**   ra + 3 : control variable
+*/
+static int forprep (lua_State *L, StkId ra) {
+  TValue *pinit = s2v(ra);
+  TValue *plimit = s2v(ra + 1);
+  TValue *pstep = s2v(ra + 2);
+  if (ttisinteger(pinit) && ttisinteger(pstep)) { /* integer loop? */
+    lua_Integer init = ivalue(pinit);
+    lua_Integer step = ivalue(pstep);
+    lua_Integer limit;
+    if (step == 0)
+      luaG_runerror(L, "'for' step is zero");
+    setivalue(s2v(ra + 3), init);  /* control variable */
+    if (forlimit(L, init, plimit, &limit, step))
+      return 1;  /* skip the loop */
+    else {  /* prepare loop counter */
+      lua_Unsigned count;
+      if (step > 0) {  /* ascending loop? */
+        count = l_castS2U(limit) - l_castS2U(init);
+        if (step != 1)  /* avoid division in the too common case */
+          count /= l_castS2U(step);
+      }
+      else {  /* step < 0; descending loop */
+        count = l_castS2U(init) - l_castS2U(limit);
+        /* 'step+1' avoids negating 'mininteger' */
+        count /= l_castS2U(-(step + 1)) + 1u;
+      }
+      /* store the counter in place of the limit (which won't be
+         needed anymore */
+      setivalue(plimit, l_castU2S(count));
+    }
+  }
+  else {  /* try making all values floats */
+    lua_Number init; lua_Number limit; lua_Number step;
+    if (unlikely(!tonumber(plimit, &limit)))
+      luaG_forerror(L, plimit, "limit");
+    if (unlikely(!tonumber(pstep, &step)))
+      luaG_forerror(L, pstep, "step");
+    if (unlikely(!tonumber(pinit, &init)))
+      luaG_forerror(L, pinit, "initial value");
+    if (step == 0)
+      luaG_runerror(L, "'for' step is zero");
+    if (luai_numlt(0, step) ? luai_numlt(limit, init)
+                            : luai_numlt(init, limit))
+      return 1;  /* skip the loop */
+    else {
+      /* make sure internal values are all floats */
+      setfltvalue(plimit, limit);
+      setfltvalue(pstep, step);
+      setfltvalue(s2v(ra), init);  /* internal index */
+      setfltvalue(s2v(ra + 3), init);  /* control variable */
+    }
+  }
+  return 0;
+}
+
+
+/*
+** Execute a step of a float numerical for loop, returning
+** true iff the loop must continue. (The integer case is
+** written online with opcode OP_FORLOOP, for performance.)
+*/
+static int floatforloop (StkId ra) {
+  lua_Number step = fltvalue(s2v(ra + 2));
+  lua_Number limit = fltvalue(s2v(ra + 1));
+  lua_Number idx = fltvalue(s2v(ra));  /* internal index */
+  idx = luai_numadd(L, idx, step);  /* increment index */
+  if (luai_numlt(0, step) ? luai_numle(idx, limit)
+                          : luai_numle(limit, idx)) {
+    chgfltvalue(s2v(ra), idx);  /* update internal index */
+    setfltvalue(s2v(ra + 3), idx);  /* and control variable */
+    return 1;  /* jump back */
+  }
+  else
+    return 0;  /* finish the loop */
+}
+
+
+/*
+** Finish the table access 'val = t[key]'.
+** if 'slot' is NULL, 't' is not a table; otherwise, 'slot' points to
+** t[k] entry (which must be empty).
+*/
+void luaV_finishget (lua_State *L, const TValue *t, TValue *key, StkId val,
+                      const TValue *slot) {
+  int loop;  /* counter to avoid infinite loops */
+  const TValue *tm;  /* metamethod */
+  for (loop = 0; loop < MAXTAGLOOP; loop++) {
+    if (slot == NULL) {  /* 't' is not a table? */
+      lua_assert(!ttistable(t));
+      tm = luaT_gettmbyobj(L, t, TM_INDEX);
+      if (unlikely(notm(tm)))
+        luaG_typeerror(L, t, "index");  /* no metamethod */
+      /* else will try the metamethod */
+    }
+    else {  /* 't' is a table */
+      lua_assert(isempty(slot));
+      tm = fasttm(L, hvalue(t)->metatable, TM_INDEX);  /* table's metamethod */
+      if (tm == NULL) {  /* no metamethod? */
+        setnilvalue(s2v(val));  /* result is nil */
+        return;
+      }
+      /* else will try the metamethod */
+    }
+    if (ttisfunction(tm)) {  /* is metamethod a function? */
+      luaT_callTMres(L, tm, t, key, val);  /* call it */
+      return;
+    }
+    t = tm;  /* else try to access 'tm[key]' */
+    if (luaV_fastget(L, t, key, slot, luaH_get)) {  /* fast track? */
+      setobj2s(L, val, slot);  /* done */
+      return;
+    }
+    /* else repeat (tail call 'luaV_finishget') */
+  }
+  luaG_runerror(L, "'__index' chain too long; possible loop");
+}
+
+
+/*
+** Finish a table assignment 't[key] = val'.
+** If 'slot' is NULL, 't' is not a table.  Otherwise, 'slot' points
+** to the entry 't[key]', or to a value with an absent key if there
+** is no such entry.  (The value at 'slot' must be empty, otherwise
+** 'luaV_fastget' would have done the job.)
+*/
+void luaV_finishset (lua_State *L, const TValue *t, TValue *key,
+                     TValue *val, const TValue *slot) {
+  int loop;  /* counter to avoid infinite loops */
+  for (loop = 0; loop < MAXTAGLOOP; loop++) {
+    const TValue *tm;  /* '__newindex' metamethod */
+    if (slot != NULL) {  /* is 't' a table? */
+      Table *h = hvalue(t);  /* save 't' table */
+      lua_assert(isempty(slot));  /* slot must be empty */
+      tm = fasttm(L, h->metatable, TM_NEWINDEX);  /* get metamethod */
+      if (tm == NULL) {  /* no metamethod? */
+        if (isabstkey(slot))  /* no previous entry? */
+          slot = luaH_newkey(L, h, key);  /* create one */
+        /* no metamethod and (now) there is an entry with given key */
+        setobj2t(L, cast(TValue *, slot), val);  /* set its new value */
+        invalidateTMcache(h);
+        luaC_barrierback(L, obj2gco(h), val);
+        return;
+      }
+      /* else will try the metamethod */
+    }
+    else {  /* not a table; check metamethod */
+      tm = luaT_gettmbyobj(L, t, TM_NEWINDEX);
+      if (unlikely(notm(tm)))
+        luaG_typeerror(L, t, "index");
+    }
+    /* try the metamethod */
+    if (ttisfunction(tm)) {
+      luaT_callTM(L, tm, t, key, val);
+      return;
+    }
+    t = tm;  /* else repeat assignment over 'tm' */
+    if (luaV_fastget(L, t, key, slot, luaH_get)) {
+      luaV_finishfastset(L, t, slot, val);
+      return;  /* done */
+    }
+    /* else 'return luaV_finishset(L, t, key, val, slot)' (loop) */
+  }
+  luaG_runerror(L, "'__newindex' chain too long; possible loop");
+}
+
+
+/*
+** Compare two strings 'ls' x 'rs', returning an integer less-equal-
+** -greater than zero if 'ls' is less-equal-greater than 'rs'.
+** The code is a little tricky because it allows '\0' in the strings
+** and it uses 'strcoll' (to respect locales) for each segments
+** of the strings.
+*/
+static int l_strcmp (const TString *ls, const TString *rs) {
+  const char *l = getstr(ls);
+  size_t ll = tsslen(ls);
+  const char *r = getstr(rs);
+  size_t lr = tsslen(rs);
+  for (;;) {  /* for each segment */
+    int temp = strcoll(l, r);
+    if (temp != 0)  /* not equal? */
+      return temp;  /* done */
+    else {  /* strings are equal up to a '\0' */
+      size_t len = strlen(l);  /* index of first '\0' in both strings */
+      if (len == lr)  /* 'rs' is finished? */
+        return (len == ll) ? 0 : 1;  /* check 'ls' */
+      else if (len == ll)  /* 'ls' is finished? */
+        return -1;  /* 'ls' is less than 'rs' ('rs' is not finished) */
+      /* both strings longer than 'len'; go on comparing after the '\0' */
+      len++;
+      l += len; ll -= len; r += len; lr -= len;
+    }
+  }
+}
+
+
+/*
+** Check whether integer 'i' is less than float 'f'. If 'i' has an
+** exact representation as a float ('l_intfitsf'), compare numbers as
+** floats. Otherwise, use the equivalence 'i < f <=> i < ceil(f)'.
+** If 'ceil(f)' is out of integer range, either 'f' is greater than
+** all integers or less than all integers.
+** (The test with 'l_intfitsf' is only for performance; the else
+** case is correct for all values, but it is slow due to the conversion
+** from float to int.)
+** When 'f' is NaN, comparisons must result in false.
+*/
+static int LTintfloat (lua_Integer i, lua_Number f) {
+  if (l_intfitsf(i))
+    return luai_numlt(cast_num(i), f);  /* compare them as floats */
+  else {  /* i < f <=> i < ceil(f) */
+    lua_Integer fi;
+    if (luaV_flttointeger(f, &fi, F2Iceil))  /* fi = ceil(f) */
+      return i < fi;   /* compare them as integers */
+    else  /* 'f' is either greater or less than all integers */
+      return f > 0;  /* greater? */
+  }
+}
+
+
+/*
+** Check whether integer 'i' is less than or equal to float 'f'.
+** See comments on previous function.
+*/
+static int LEintfloat (lua_Integer i, lua_Number f) {
+  if (l_intfitsf(i))
+    return luai_numle(cast_num(i), f);  /* compare them as floats */
+  else {  /* i <= f <=> i <= floor(f) */
+    lua_Integer fi;
+    if (luaV_flttointeger(f, &fi, F2Ifloor))  /* fi = floor(f) */
+      return i <= fi;   /* compare them as integers */
+    else  /* 'f' is either greater or less than all integers */
+      return f > 0;  /* greater? */
+  }
+}
+
+
+/*
+** Check whether float 'f' is less than integer 'i'.
+** See comments on previous function.
+*/
+static int LTfloatint (lua_Number f, lua_Integer i) {
+  if (l_intfitsf(i))
+    return luai_numlt(f, cast_num(i));  /* compare them as floats */
+  else {  /* f < i <=> floor(f) < i */
+    lua_Integer fi;
+    if (luaV_flttointeger(f, &fi, F2Ifloor))  /* fi = floor(f) */
+      return fi < i;   /* compare them as integers */
+    else  /* 'f' is either greater or less than all integers */
+      return f < 0;  /* less? */
+  }
+}
+
+
+/*
+** Check whether float 'f' is less than or equal to integer 'i'.
+** See comments on previous function.
+*/
+static int LEfloatint (lua_Number f, lua_Integer i) {
+  if (l_intfitsf(i))
+    return luai_numle(f, cast_num(i));  /* compare them as floats */
+  else {  /* f <= i <=> ceil(f) <= i */
+    lua_Integer fi;
+    if (luaV_flttointeger(f, &fi, F2Iceil))  /* fi = ceil(f) */
+      return fi <= i;   /* compare them as integers */
+    else  /* 'f' is either greater or less than all integers */
+      return f < 0;  /* less? */
+  }
+}
+
+
+/*
+** Return 'l < r', for numbers.
+*/
+static int LTnum (const TValue *l, const TValue *r) {
+  lua_assert(ttisnumber(l) && ttisnumber(r));
+  if (ttisinteger(l)) {
+    lua_Integer li = ivalue(l);
+    if (ttisinteger(r))
+      return li < ivalue(r);  /* both are integers */
+    else  /* 'l' is int and 'r' is float */
+      return LTintfloat(li, fltvalue(r));  /* l < r ? */
+  }
+  else {
+    lua_Number lf = fltvalue(l);  /* 'l' must be float */
+    if (ttisfloat(r))
+      return luai_numlt(lf, fltvalue(r));  /* both are float */
+    else  /* 'l' is float and 'r' is int */
+      return LTfloatint(lf, ivalue(r));
+  }
+}
+
+
+/*
+** Return 'l <= r', for numbers.
+*/
+static int LEnum (const TValue *l, const TValue *r) {
+  lua_assert(ttisnumber(l) && ttisnumber(r));
+  if (ttisinteger(l)) {
+    lua_Integer li = ivalue(l);
+    if (ttisinteger(r))
+      return li <= ivalue(r);  /* both are integers */
+    else  /* 'l' is int and 'r' is float */
+      return LEintfloat(li, fltvalue(r));  /* l <= r ? */
+  }
+  else {
+    lua_Number lf = fltvalue(l);  /* 'l' must be float */
+    if (ttisfloat(r))
+      return luai_numle(lf, fltvalue(r));  /* both are float */
+    else  /* 'l' is float and 'r' is int */
+      return LEfloatint(lf, ivalue(r));
+  }
+}
+
+
+/*
+** return 'l < r' for non-numbers.
+*/
+static int lessthanothers (lua_State *L, const TValue *l, const TValue *r) {
+  lua_assert(!ttisnumber(l) || !ttisnumber(r));
+  if (ttisstring(l) && ttisstring(r))  /* both are strings? */
+    return l_strcmp(tsvalue(l), tsvalue(r)) < 0;
+  else
+    return luaT_callorderTM(L, l, r, TM_LT);
+}
+
+
+/*
+** Main operation less than; return 'l < r'.
+*/
+int luaV_lessthan (lua_State *L, const TValue *l, const TValue *r) {
+  if (ttisnumber(l) && ttisnumber(r))  /* both operands are numbers? */
+    return LTnum(l, r);
+  else return lessthanothers(L, l, r);
+}
+
+
+/*
+** return 'l <= r' for non-numbers.
+*/
+static int lessequalothers (lua_State *L, const TValue *l, const TValue *r) {
+  lua_assert(!ttisnumber(l) || !ttisnumber(r));
+  if (ttisstring(l) && ttisstring(r))  /* both are strings? */
+    return l_strcmp(tsvalue(l), tsvalue(r)) <= 0;
+  else
+    return luaT_callorderTM(L, l, r, TM_LE);
+}
+
+
+/*
+** Main operation less than or equal to; return 'l <= r'.
+*/
+int luaV_lessequal (lua_State *L, const TValue *l, const TValue *r) {
+  if (ttisnumber(l) && ttisnumber(r))  /* both operands are numbers? */
+    return LEnum(l, r);
+  else return lessequalothers(L, l, r);
+}
+
+
+/*
+** Main operation for equality of Lua values; return 't1 == t2'.
+** L == NULL means raw equality (no metamethods)
+*/
+int luaV_equalobj (lua_State *L, const TValue *t1, const TValue *t2) {
+  const TValue *tm;
+  if (ttypetag(t1) != ttypetag(t2)) {  /* not the same variant? */
+    if (ttype(t1) != ttype(t2) || ttype(t1) != LUA_TNUMBER)
+      return 0;  /* only numbers can be equal with different variants */
+    else {  /* two numbers with different variants */
+      lua_Integer i1, i2;  /* compare them as integers */
+      return (tointegerns(t1, &i1) && tointegerns(t2, &i2) && i1 == i2);
+    }
+  }
+  /* values have same type and same variant */
+  switch (ttypetag(t1)) {
+    case LUA_VNIL: case LUA_VFALSE: case LUA_VTRUE: return 1;
+    case LUA_VNUMINT: return (ivalue(t1) == ivalue(t2));
+    case LUA_VNUMFLT: return luai_numeq(fltvalue(t1), fltvalue(t2));
+    case LUA_VLIGHTUSERDATA: return pvalue(t1) == pvalue(t2);
+    case LUA_VLCF: return fvalue(t1) == fvalue(t2);
+    case LUA_VSHRSTR: return eqshrstr(tsvalue(t1), tsvalue(t2));
+    case LUA_VLNGSTR: return luaS_eqlngstr(tsvalue(t1), tsvalue(t2));
+    case LUA_VUSERDATA: {
+      if (uvalue(t1) == uvalue(t2)) return 1;
+      else if (L == NULL) return 0;
+      tm = fasttm(L, uvalue(t1)->metatable, TM_EQ);
+      if (tm == NULL)
+        tm = fasttm(L, uvalue(t2)->metatable, TM_EQ);
+      break;  /* will try TM */
+    }
+    case LUA_VTABLE: {
+      if (hvalue(t1) == hvalue(t2)) return 1;
+      else if (L == NULL) return 0;
+      tm = fasttm(L, hvalue(t1)->metatable, TM_EQ);
+      if (tm == NULL)
+        tm = fasttm(L, hvalue(t2)->metatable, TM_EQ);
+      break;  /* will try TM */
+    }
+    default:
+      return gcvalue(t1) == gcvalue(t2);
+  }
+  if (tm == NULL)  /* no TM? */
+    return 0;  /* objects are different */
+  else {
+    luaT_callTMres(L, tm, t1, t2, L->top);  /* call TM */
+    return !l_isfalse(s2v(L->top));
+  }
+}
+
+
+/* macro used by 'luaV_concat' to ensure that element at 'o' is a string */
+#define tostring(L,o)  \
+	(ttisstring(o) || (cvt2str(o) && (luaO_tostring(L, o), 1)))
+
+#define isemptystr(o)	(ttisshrstring(o) && tsvalue(o)->shrlen == 0)
+
+/* copy strings in stack from top - n up to top - 1 to buffer */
+static void copy2buff (StkId top, int n, char *buff) {
+  size_t tl = 0;  /* size already copied */
+  do {
+    size_t l = vslen(s2v(top - n));  /* length of string being copied */
+    memcpy(buff + tl, svalue(s2v(top - n)), l * sizeof(char));
+    tl += l;
+  } while (--n > 0);
+}
+
+
+/*
+** Main operation for concatenation: concat 'total' values in the stack,
+** from 'L->top - total' up to 'L->top - 1'.
+*/
+void luaV_concat (lua_State *L, int total) {
+  lua_assert(total >= 2);
+  do {
+    StkId top = L->top;
+    int n = 2;  /* number of elements handled in this pass (at least 2) */
+    if (!(ttisstring(s2v(top - 2)) || cvt2str(s2v(top - 2))) ||
+        !tostring(L, s2v(top - 1)))
+      luaT_tryconcatTM(L);
+    else if (isemptystr(s2v(top - 1)))  /* second operand is empty? */
+      cast_void(tostring(L, s2v(top - 2)));  /* result is first operand */
+    else if (isemptystr(s2v(top - 2))) {  /* first operand is empty string? */
+      setobjs2s(L, top - 2, top - 1);  /* result is second op. */
+    }
+    else {
+      /* at least two non-empty string values; get as many as possible */
+      size_t tl = vslen(s2v(top - 1));
+      TString *ts;
+      /* collect total length and number of strings */
+      for (n = 1; n < total && tostring(L, s2v(top - n - 1)); n++) {
+        size_t l = vslen(s2v(top - n - 1));
+        if (unlikely(l >= (MAX_SIZE/sizeof(char)) - tl))
+          luaG_runerror(L, "string length overflow");
+        tl += l;
+      }
+      if (tl <= LUAI_MAXSHORTLEN) {  /* is result a short string? */
+        char buff[LUAI_MAXSHORTLEN];
+        copy2buff(top, n, buff);  /* copy strings to buffer */
+        ts = luaS_newlstr(L, buff, tl);
+      }
+      else {  /* long string; copy strings directly to final result */
+        ts = luaS_createlngstrobj(L, tl);
+        copy2buff(top, n, getstr(ts));
+      }
+      setsvalue2s(L, top - n, ts);  /* create result */
+    }
+    total -= n-1;  /* got 'n' strings to create 1 new */
+    L->top -= n-1;  /* popped 'n' strings and pushed one */
+  } while (total > 1);  /* repeat until only 1 result left */
+}
+
+
+/*
+** Main operation 'ra = #rb'.
+*/
+void luaV_objlen (lua_State *L, StkId ra, const TValue *rb) {
+  const TValue *tm;
+  switch (ttypetag(rb)) {
+    case LUA_VTABLE: {
+      Table *h = hvalue(rb);
+      tm = fasttm(L, h->metatable, TM_LEN);
+      if (tm) break;  /* metamethod? break switch to call it */
+      setivalue(s2v(ra), luaH_getn(h));  /* else primitive len */
+      return;
+    }
+    case LUA_VSHRSTR: {
+      setivalue(s2v(ra), tsvalue(rb)->shrlen);
+      return;
+    }
+    case LUA_VLNGSTR: {
+      setivalue(s2v(ra), tsvalue(rb)->u.lnglen);
+      return;
+    }
+    default: {  /* try metamethod */
+      tm = luaT_gettmbyobj(L, rb, TM_LEN);
+      if (unlikely(notm(tm)))  /* no metamethod? */
+        luaG_typeerror(L, rb, "get length of");
+      break;
+    }
+  }
+  luaT_callTMres(L, tm, rb, rb, ra);
+}
+
+
+/*
+** Integer division; return 'm // n', that is, floor(m/n).
+** C division truncates its result (rounds towards zero).
+** 'floor(q) == trunc(q)' when 'q >= 0' or when 'q' is integer,
+** otherwise 'floor(q) == trunc(q) - 1'.
+*/
+lua_Integer luaV_idiv (lua_State *L, lua_Integer m, lua_Integer n) {
+  if (unlikely(l_castS2U(n) + 1u <= 1u)) {  /* special cases: -1 or 0 */
+    if (n == 0)
+      luaG_runerror(L, "attempt to divide by zero");
+    return intop(-, 0, m);   /* n==-1; avoid overflow with 0x80000...//-1 */
+  }
+  else {
+    lua_Integer q = m / n;  /* perform C division */
+    if ((m ^ n) < 0 && m % n != 0)  /* 'm/n' would be negative non-integer? */
+      q -= 1;  /* correct result for different rounding */
+    return q;
+  }
+}
+
+
+/*
+** Integer modulus; return 'm % n'. (Assume that C '%' with
+** negative operands follows C99 behavior. See previous comment
+** about luaV_idiv.)
+*/
+lua_Integer luaV_mod (lua_State *L, lua_Integer m, lua_Integer n) {
+  if (unlikely(l_castS2U(n) + 1u <= 1u)) {  /* special cases: -1 or 0 */
+    if (n == 0)
+      luaG_runerror(L, "attempt to perform 'n%%0'");
+    return 0;   /* m % -1 == 0; avoid overflow with 0x80000...%-1 */
+  }
+  else {
+    lua_Integer r = m % n;
+    if (r != 0 && (r ^ n) < 0)  /* 'm/n' would be non-integer negative? */
+      r += n;  /* correct result for different rounding */
+    return r;
+  }
+}
+
+
+/*
+** Float modulus
+*/
+lua_Number luaV_modf (lua_State *L, lua_Number m, lua_Number n) {
+  lua_Number r;
+  luai_nummod(L, m, n, r);
+  return r;
+}
+
+
+/* number of bits in an integer */
+#define NBITS	cast_int(sizeof(lua_Integer) * CHAR_BIT)
+
+/*
+** Shift left operation. (Shift right just negates 'y'.)
+*/
+#define luaV_shiftr(x,y)	luaV_shiftl(x,-(y))
+
+lua_Integer luaV_shiftl (lua_Integer x, lua_Integer y) {
+  if (y < 0) {  /* shift right? */
+    if (y <= -NBITS) return 0;
+    else return intop(>>, x, -y);
+  }
+  else {  /* shift left */
+    if (y >= NBITS) return 0;
+    else return intop(<<, x, y);
+  }
+}
+
+
+/*
+** create a new Lua closure, push it in the stack, and initialize
+** its upvalues.
+*/
+static void pushclosure (lua_State *L, Proto *p, UpVal **encup, StkId base,
+                         StkId ra) {
+  int nup = p->sizeupvalues;
+  Upvaldesc *uv = p->upvalues;
+  int i;
+  LClosure *ncl = luaF_newLclosure(L, nup);
+  ncl->p = p;
+  setclLvalue2s(L, ra, ncl);  /* anchor new closure in stack */
+  for (i = 0; i < nup; i++) {  /* fill in its upvalues */
+    if (uv[i].instack)  /* upvalue refers to local variable? */
+      ncl->upvals[i] = luaF_findupval(L, base + uv[i].idx);
+    else  /* get upvalue from enclosing function */
+      ncl->upvals[i] = encup[uv[i].idx];
+    luaC_objbarrier(L, ncl, ncl->upvals[i]);
+  }
+}
+
+
+/*
+** finish execution of an opcode interrupted by a yield
+*/
+void luaV_finishOp (lua_State *L) {
+  CallInfo *ci = L->ci;
+  StkId base = ci->func + 1;
+  Instruction inst = *(ci->u.l.savedpc - 1);  /* interrupted instruction */
+  OpCode op = GET_OPCODE(inst);
+  switch (op) {  /* finish its execution */
+    case OP_MMBIN: case OP_MMBINI: case OP_MMBINK: {
+      setobjs2s(L, base + GETARG_A(*(ci->u.l.savedpc - 2)), --L->top);
+      break;
+    }
+    case OP_UNM: case OP_BNOT: case OP_LEN:
+    case OP_GETTABUP: case OP_GETTABLE: case OP_GETI:
+    case OP_GETFIELD: case OP_SELF: {
+      setobjs2s(L, base + GETARG_A(inst), --L->top);
+      break;
+    }
+    case OP_LT: case OP_LE:
+    case OP_LTI: case OP_LEI:
+    case OP_GTI: case OP_GEI:
+    case OP_EQ: {  /* note that 'OP_EQI'/'OP_EQK' cannot yield */
+      int res = !l_isfalse(s2v(L->top - 1));
+      L->top--;
+#if defined(LUA_COMPAT_LT_LE)
+      if (ci->callstatus & CIST_LEQ) {  /* "<=" using "<" instead? */
+        ci->callstatus ^= CIST_LEQ;  /* clear mark */
+        res = !res;  /* negate result */
+      }
+#endif
+      lua_assert(GET_OPCODE(*ci->u.l.savedpc) == OP_JMP);
+      if (res != GETARG_k(inst))  /* condition failed? */
+        ci->u.l.savedpc++;  /* skip jump instruction */
+      break;
+    }
+    case OP_CONCAT: {
+      StkId top = L->top - 1;  /* top when 'luaT_tryconcatTM' was called */
+      int a = GETARG_A(inst);      /* first element to concatenate */
+      int total = cast_int(top - 1 - (base + a));  /* yet to concatenate */
+      setobjs2s(L, top - 2, top);  /* put TM result in proper position */
+      if (total > 1) {  /* are there elements to concat? */
+        L->top = top - 1;  /* top is one after last element (at top-2) */
+        luaV_concat(L, total);  /* concat them (may yield again) */
+      }
+      break;
+    }
+    default: {
+      /* only these other opcodes can yield */
+      lua_assert(op == OP_TFORCALL || op == OP_CALL ||
+           op == OP_TAILCALL || op == OP_SETTABUP || op == OP_SETTABLE ||
+           op == OP_SETI || op == OP_SETFIELD);
+      break;
+    }
+  }
+}
+
+
+
+
+/*
+** {==================================================================
+** Macros for arithmetic/bitwise/comparison opcodes in 'luaV_execute'
+** ===================================================================
+*/
+
+#define l_addi(L,a,b)	intop(+, a, b)
+#define l_subi(L,a,b)	intop(-, a, b)
+#define l_muli(L,a,b)	intop(*, a, b)
+#define l_band(a,b)	intop(&, a, b)
+#define l_bor(a,b)	intop(|, a, b)
+#define l_bxor(a,b)	intop(^, a, b)
+
+#define l_lti(a,b)	(a < b)
+#define l_lei(a,b)	(a <= b)
+#define l_gti(a,b)	(a > b)
+#define l_gei(a,b)	(a >= b)
+
+
+/*
+** Arithmetic operations with immediate operands. 'iop' is the integer
+** operation, 'fop' is the float operation.
+*/
+#define op_arithI(L,iop,fop) {  \
+  TValue *v1 = vRB(i);  \
+  int imm = GETARG_sC(i);  \
+  if (ttisinteger(v1)) {  \
+    lua_Integer iv1 = ivalue(v1);  \
+    pc++; setivalue(s2v(ra), iop(L, iv1, imm));  \
+  }  \
+  else if (ttisfloat(v1)) {  \
+    lua_Number nb = fltvalue(v1);  \
+    lua_Number fimm = cast_num(imm);  \
+    pc++; setfltvalue(s2v(ra), fop(L, nb, fimm)); \
+  }}
+
+
+/*
+** Auxiliary function for arithmetic operations over floats and others
+** with two register operands.
+*/
+#define op_arithf_aux(L,v1,v2,fop) {  \
+  lua_Number n1; lua_Number n2;  \
+  if (tonumberns(v1, n1) && tonumberns(v2, n2)) {  \
+    pc++; setfltvalue(s2v(ra), fop(L, n1, n2));  \
+  }}
+
+
+/*
+** Arithmetic operations over floats and others with register operands.
+*/
+#define op_arithf(L,fop) {  \
+  TValue *v1 = vRB(i);  \
+  TValue *v2 = vRC(i);  \
+  op_arithf_aux(L, v1, v2, fop); }
+
+
+/*
+** Arithmetic operations with K operands for floats.
+*/
+#define op_arithfK(L,fop) {  \
+  TValue *v1 = vRB(i);  \
+  TValue *v2 = KC(i);  \
+  op_arithf_aux(L, v1, v2, fop); }
+
+
+/*
+** Arithmetic operations over integers and floats.
+*/
+#define op_arith_aux(L,v1,v2,iop,fop) {  \
+  if (ttisinteger(v1) && ttisinteger(v2)) {  \
+    lua_Integer i1 = ivalue(v1); lua_Integer i2 = ivalue(v2);  \
+    pc++; setivalue(s2v(ra), iop(L, i1, i2));  \
+  }  \
+  else op_arithf_aux(L, v1, v2, fop); }
+
+
+/*
+** Arithmetic operations with register operands.
+*/
+#define op_arith(L,iop,fop) {  \
+  TValue *v1 = vRB(i);  \
+  TValue *v2 = vRC(i);  \
+  op_arith_aux(L, v1, v2, iop, fop); }
+
+
+/*
+** Arithmetic operations with K operands.
+*/
+#define op_arithK(L,iop,fop) {  \
+  TValue *v1 = vRB(i);  \
+  TValue *v2 = KC(i);  \
+  op_arith_aux(L, v1, v2, iop, fop); }
+
+
+/*
+** Bitwise operations with constant operand.
+*/
+#define op_bitwiseK(L,op) {  \
+  TValue *v1 = vRB(i);  \
+  TValue *v2 = KC(i);  \
+  lua_Integer i1;  \
+  lua_Integer i2 = ivalue(v2);  \
+  if (tointegerns(v1, &i1)) {  \
+    pc++; setivalue(s2v(ra), op(i1, i2));  \
+  }}
+
+
+/*
+** Bitwise operations with register operands.
+*/
+#define op_bitwise(L,op) {  \
+  TValue *v1 = vRB(i);  \
+  TValue *v2 = vRC(i);  \
+  lua_Integer i1; lua_Integer i2;  \
+  if (tointegerns(v1, &i1) && tointegerns(v2, &i2)) {  \
+    pc++; setivalue(s2v(ra), op(i1, i2));  \
+  }}
+
+
+/*
+** Order operations with register operands. 'opn' actually works
+** for all numbers, but the fast track improves performance for
+** integers.
+*/
+#define op_order(L,opi,opn,other) {  \
+        int cond;  \
+        TValue *rb = vRB(i);  \
+        if (ttisinteger(s2v(ra)) && ttisinteger(rb)) {  \
+          lua_Integer ia = ivalue(s2v(ra));  \
+          lua_Integer ib = ivalue(rb);  \
+          cond = opi(ia, ib);  \
+        }  \
+        else if (ttisnumber(s2v(ra)) && ttisnumber(rb))  \
+          cond = opn(s2v(ra), rb);  \
+        else  \
+          Protect(cond = other(L, s2v(ra), rb));  \
+        docondjump(); }
+
+
+/*
+** Order operations with immediate operand. (Immediate operand is
+** always small enough to have an exact representation as a float.)
+*/
+#define op_orderI(L,opi,opf,inv,tm) {  \
+        int cond;  \
+        int im = GETARG_sB(i);  \
+        if (ttisinteger(s2v(ra)))  \
+          cond = opi(ivalue(s2v(ra)), im);  \
+        else if (ttisfloat(s2v(ra))) {  \
+          lua_Number fa = fltvalue(s2v(ra));  \
+          lua_Number fim = cast_num(im);  \
+          cond = opf(fa, fim);  \
+        }  \
+        else {  \
+          int isf = GETARG_C(i);  \
+          Protect(cond = luaT_callorderiTM(L, s2v(ra), im, inv, isf, tm));  \
+        }  \
+        docondjump(); }
+
+/* }================================================================== */
+
+
+/*
+** {==================================================================
+** Function 'luaV_execute': main interpreter loop
+** ===================================================================
+*/
+
+/*
+** some macros for common tasks in 'luaV_execute'
+*/
+
+
+#define RA(i)	(base+GETARG_A(i))
+#define RB(i)	(base+GETARG_B(i))
+#define vRB(i)	s2v(RB(i))
+#define KB(i)	(k+GETARG_B(i))
+#define RC(i)	(base+GETARG_C(i))
+#define vRC(i)	s2v(RC(i))
+#define KC(i)	(k+GETARG_C(i))
+#define RKC(i)	((TESTARG_k(i)) ? k + GETARG_C(i) : s2v(base + GETARG_C(i)))
+
+
+
+#define updatetrap(ci)  (trap = ci->u.l.trap)
+
+#define updatebase(ci)	(base = ci->func + 1)
+
+
+#define updatestack(ci) { if (trap) { updatebase(ci); ra = RA(i); } }
+
+
+/*
+** Execute a jump instruction. The 'updatetrap' allows signals to stop
+** tight loops. (Without it, the local copy of 'trap' could never change.)
+*/
+#define dojump(ci,i,e)	{ pc += GETARG_sJ(i) + e; updatetrap(ci); }
+
+
+/* for test instructions, execute the jump instruction that follows it */
+#define donextjump(ci)	{ Instruction ni = *pc; dojump(ci, ni, 1); }
+
+/*
+** do a conditional jump: skip next instruction if 'cond' is not what
+** was expected (parameter 'k'), else do next instruction, which must
+** be a jump.
+*/
+#define docondjump()	if (cond != GETARG_k(i)) pc++; else donextjump(ci);
+
+
+/*
+** Correct global 'pc'.
+*/
+#define savepc(L)	(ci->u.l.savedpc = pc)
+
+
+/*
+** Whenever code can raise errors, the global 'pc' and the global
+** 'top' must be correct to report occasional errors.
+*/
+#define savestate(L,ci)		(savepc(L), L->top = ci->top)
+
+
+/*
+** Protect code that, in general, can raise errors, reallocate the
+** stack, and change the hooks.
+*/
+#define Protect(exp)  (savestate(L,ci), (exp), updatetrap(ci))
+
+/* special version that does not change the top */
+#define ProtectNT(exp)  (savepc(L), (exp), updatetrap(ci))
+
+/*
+** Protect code that will finish the loop (returns) or can only raise
+** errors. (That is, it will not return to the interpreter main loop
+** after changing the stack or hooks.)
+*/
+#define halfProtect(exp)  (savestate(L,ci), (exp))
+
+/* idem, but without changing the stack */
+#define halfProtectNT(exp)  (savepc(L), (exp))
+
+
+#define checkGC(L,c)  \
+	{ luaC_condGC(L, L->top = (c),  /* limit of live values */ \
+                         updatetrap(ci)); \
+           luai_threadyield(L); }
+
+
+/* fetch an instruction and prepare its execution */
+#define vmfetch()	{ \
+  if (trap) {  /* stack reallocation or hooks? */ \
+    trap = luaG_traceexec(L, pc);  /* handle hooks */ \
+    updatebase(ci);  /* correct stack */ \
+  } \
+  i = *(pc++); \
+  ra = RA(i); /* WARNING: any stack reallocation invalidates 'ra' */ \
+}
+
+#define vmdispatch(o)	switch(o)
+#define vmcase(l)	case l:
+#define vmbreak		break
+
+
+void luaV_execute (lua_State *L, CallInfo *ci) {
+  LClosure *cl;
+  TValue *k;
+  StkId base;
+  const Instruction *pc;
+  int trap;
+#if LUA_USE_JUMPTABLE
+#include "ljumptab.h"
+#endif
+ tailcall:
+  trap = L->hookmask;
+  cl = clLvalue(s2v(ci->func));
+  k = cl->p->k;
+  pc = ci->u.l.savedpc;
+  if (trap) {
+    if (cl->p->is_vararg)
+      trap = 0;  /* hooks will start after VARARGPREP instruction */
+    else if (pc == cl->p->code)  /* first instruction (not resuming)? */
+      luaD_hookcall(L, ci);
+    ci->u.l.trap = 1;  /* there may be other hooks */
+  }
+  base = ci->func + 1;
+  /* main loop of interpreter */
+  for (;;) {
+    Instruction i;  /* instruction being executed */
+    StkId ra;  /* instruction's A register */
+    vmfetch();
+    lua_assert(base == ci->func + 1);
+    lua_assert(base <= L->top && L->top < L->stack + L->stacksize);
+    /* invalidate top for instructions not expecting it */
+    lua_assert(isIT(i) || (cast_void(L->top = base), 1));
+    vmdispatch (GET_OPCODE(i)) {
+      vmcase(OP_MOVE) {
+        setobjs2s(L, ra, RB(i));
+        vmbreak;
+      }
+      vmcase(OP_LOADI) {
+        lua_Integer b = GETARG_sBx(i);
+        setivalue(s2v(ra), b);
+        vmbreak;
+      }
+      vmcase(OP_LOADF) {
+        int b = GETARG_sBx(i);
+        setfltvalue(s2v(ra), cast_num(b));
+        vmbreak;
+      }
+      vmcase(OP_LOADK) {
+        TValue *rb = k + GETARG_Bx(i);
+        setobj2s(L, ra, rb);
+        vmbreak;
+      }
+      vmcase(OP_LOADKX) {
+        TValue *rb;
+        rb = k + GETARG_Ax(*pc); pc++;
+        setobj2s(L, ra, rb);
+        vmbreak;
+      }
+      vmcase(OP_LOADFALSE) {
+        setbfvalue(s2v(ra));
+        vmbreak;
+      }
+      vmcase(OP_LFALSESKIP) {
+        setbfvalue(s2v(ra));
+        pc++;  /* skip next instruction */
+        vmbreak;
+      }
+      vmcase(OP_LOADTRUE) {
+        setbtvalue(s2v(ra));
+        vmbreak;
+      }
+      vmcase(OP_LOADNIL) {
+        int b = GETARG_B(i);
+        do {
+          setnilvalue(s2v(ra++));
+        } while (b--);
+        vmbreak;
+      }
+      vmcase(OP_GETUPVAL) {
+        int b = GETARG_B(i);
+        setobj2s(L, ra, cl->upvals[b]->v);
+        vmbreak;
+      }
+      vmcase(OP_SETUPVAL) {
+        UpVal *uv = cl->upvals[GETARG_B(i)];
+        setobj(L, uv->v, s2v(ra));
+        luaC_barrier(L, uv, s2v(ra));
+        vmbreak;
+      }
+      vmcase(OP_GETTABUP) {
+        const TValue *slot;
+        TValue *upval = cl->upvals[GETARG_B(i)]->v;
+        TValue *rc = KC(i);
+        TString *key = tsvalue(rc);  /* key must be a string */
+        if (luaV_fastget(L, upval, key, slot, luaH_getshortstr)) {
+          setobj2s(L, ra, slot);
+        }
+        else
+          Protect(luaV_finishget(L, upval, rc, ra, slot));
+        vmbreak;
+      }
+      vmcase(OP_GETTABLE) {
+        const TValue *slot;
+        TValue *rb = vRB(i);
+        TValue *rc = vRC(i);
+        lua_Unsigned n;
+        if (ttisinteger(rc)  /* fast track for integers? */
+            ? (cast_void(n = ivalue(rc)), luaV_fastgeti(L, rb, n, slot))
+            : luaV_fastget(L, rb, rc, slot, luaH_get)) {
+          setobj2s(L, ra, slot);
+        }
+        else
+          Protect(luaV_finishget(L, rb, rc, ra, slot));
+        vmbreak;
+      }
+      vmcase(OP_GETI) {
+        const TValue *slot;
+        TValue *rb = vRB(i);
+        int c = GETARG_C(i);
+        if (luaV_fastgeti(L, rb, c, slot)) {
+          setobj2s(L, ra, slot);
+        }
+        else {
+          TValue key;
+          setivalue(&key, c);
+          Protect(luaV_finishget(L, rb, &key, ra, slot));
+        }
+        vmbreak;
+      }
+      vmcase(OP_GETFIELD) {
+        const TValue *slot;
+        TValue *rb = vRB(i);
+        TValue *rc = KC(i);
+        TString *key = tsvalue(rc);  /* key must be a string */
+        if (luaV_fastget(L, rb, key, slot, luaH_getshortstr)) {
+          setobj2s(L, ra, slot);
+        }
+        else
+          Protect(luaV_finishget(L, rb, rc, ra, slot));
+        vmbreak;
+      }
+      vmcase(OP_SETTABUP) {
+        const TValue *slot;
+        TValue *upval = cl->upvals[GETARG_A(i)]->v;
+        TValue *rb = KB(i);
+        TValue *rc = RKC(i);
+        TString *key = tsvalue(rb);  /* key must be a string */
+        if (luaV_fastget(L, upval, key, slot, luaH_getshortstr)) {
+          luaV_finishfastset(L, upval, slot, rc);
+        }
+        else
+          Protect(luaV_finishset(L, upval, rb, rc, slot));
+        vmbreak;
+      }
+      vmcase(OP_SETTABLE) {
+        const TValue *slot;
+        TValue *rb = vRB(i);  /* key (table is in 'ra') */
+        TValue *rc = RKC(i);  /* value */
+        lua_Unsigned n;
+        if (ttisinteger(rb)  /* fast track for integers? */
+            ? (cast_void(n = ivalue(rb)), luaV_fastgeti(L, s2v(ra), n, slot))
+            : luaV_fastget(L, s2v(ra), rb, slot, luaH_get)) {
+          luaV_finishfastset(L, s2v(ra), slot, rc);
+        }
+        else
+          Protect(luaV_finishset(L, s2v(ra), rb, rc, slot));
+        vmbreak;
+      }
+      vmcase(OP_SETI) {
+        const TValue *slot;
+        int c = GETARG_B(i);
+        TValue *rc = RKC(i);
+        if (luaV_fastgeti(L, s2v(ra), c, slot)) {
+          luaV_finishfastset(L, s2v(ra), slot, rc);
+        }
+        else {
+          TValue key;
+          setivalue(&key, c);
+          Protect(luaV_finishset(L, s2v(ra), &key, rc, slot));
+        }
+        vmbreak;
+      }
+      vmcase(OP_SETFIELD) {
+        const TValue *slot;
+        TValue *rb = KB(i);
+        TValue *rc = RKC(i);
+        TString *key = tsvalue(rb);  /* key must be a string */
+        if (luaV_fastget(L, s2v(ra), key, slot, luaH_getshortstr)) {
+          luaV_finishfastset(L, s2v(ra), slot, rc);
+        }
+        else
+          Protect(luaV_finishset(L, s2v(ra), rb, rc, slot));
+        vmbreak;
+      }
+      vmcase(OP_NEWTABLE) {
+        int b = GETARG_B(i);  /* log2(hash size) + 1 */
+        int c = GETARG_C(i);  /* array size */
+        Table *t;
+        if (b > 0)
+          b = 1 << (b - 1);  /* size is 2^(b - 1) */
+        lua_assert((!TESTARG_k(i)) == (GETARG_Ax(*pc) == 0));
+        if (TESTARG_k(i))  /* non-zero extra argument? */
+          c += GETARG_Ax(*pc) * (MAXARG_C + 1);  /* add it to size */
+        pc++;  /* skip extra argument */
+        L->top = ra + 1;  /* correct top in case of emergency GC */
+        t = luaH_new(L);  /* memory allocation */
+        sethvalue2s(L, ra, t);
+        if (b != 0 || c != 0)
+          luaH_resize(L, t, c, b);  /* idem */
+        checkGC(L, ra + 1);
+        vmbreak;
+      }
+      vmcase(OP_SELF) {
+        const TValue *slot;
+        TValue *rb = vRB(i);
+        TValue *rc = RKC(i);
+        TString *key = tsvalue(rc);  /* key must be a string */
+        setobj2s(L, ra + 1, rb);
+        if (luaV_fastget(L, rb, key, slot, luaH_getstr)) {
+          setobj2s(L, ra, slot);
+        }
+        else
+          Protect(luaV_finishget(L, rb, rc, ra, slot));
+        vmbreak;
+      }
+      vmcase(OP_ADDI) {
+        op_arithI(L, l_addi, luai_numadd);
+        vmbreak;
+      }
+      vmcase(OP_ADDK) {
+        op_arithK(L, l_addi, luai_numadd);
+        vmbreak;
+      }
+      vmcase(OP_SUBK) {
+        op_arithK(L, l_subi, luai_numsub);
+        vmbreak;
+      }
+      vmcase(OP_MULK) {
+        op_arithK(L, l_muli, luai_nummul);
+        vmbreak;
+      }
+      vmcase(OP_MODK) {
+        op_arithK(L, luaV_mod, luaV_modf);
+        vmbreak;
+      }
+      vmcase(OP_POWK) {
+        op_arithfK(L, luai_numpow);
+        vmbreak;
+      }
+      vmcase(OP_DIVK) {
+        op_arithfK(L, luai_numdiv);
+        vmbreak;
+      }
+      vmcase(OP_IDIVK) {
+        op_arithK(L, luaV_idiv, luai_numidiv);
+        vmbreak;
+      }
+      vmcase(OP_BANDK) {
+        op_bitwiseK(L, l_band);
+        vmbreak;
+      }
+      vmcase(OP_BORK) {
+        op_bitwiseK(L, l_bor);
+        vmbreak;
+      }
+      vmcase(OP_BXORK) {
+        op_bitwiseK(L, l_bxor);
+        vmbreak;
+      }
+      vmcase(OP_SHRI) {
+        TValue *rb = vRB(i);
+        int ic = GETARG_sC(i);
+        lua_Integer ib;
+        if (tointegerns(rb, &ib)) {
+          pc++; setivalue(s2v(ra), luaV_shiftl(ib, -ic));
+        }
+        vmbreak;
+      }
+      vmcase(OP_SHLI) {
+        TValue *rb = vRB(i);
+        int ic = GETARG_sC(i);
+        lua_Integer ib;
+        if (tointegerns(rb, &ib)) {
+          pc++; setivalue(s2v(ra), luaV_shiftl(ic, ib));
+        }
+        vmbreak;
+      }
+      vmcase(OP_ADD) {
+        op_arith(L, l_addi, luai_numadd);
+        vmbreak;
+      }
+      vmcase(OP_SUB) {
+        op_arith(L, l_subi, luai_numsub);
+        vmbreak;
+      }
+      vmcase(OP_MUL) {
+        op_arith(L, l_muli, luai_nummul);
+        vmbreak;
+      }
+      vmcase(OP_MOD) {
+        op_arith(L, luaV_mod, luaV_modf);
+        vmbreak;
+      }
+      vmcase(OP_POW) {
+        op_arithf(L, luai_numpow);
+        vmbreak;
+      }
+      vmcase(OP_DIV) {  /* float division (always with floats) */
+        op_arithf(L, luai_numdiv);
+        vmbreak;
+      }
+      vmcase(OP_IDIV) {  /* floor division */
+        op_arith(L, luaV_idiv, luai_numidiv);
+        vmbreak;
+      }
+      vmcase(OP_BAND) {
+        op_bitwise(L, l_band);
+        vmbreak;
+      }
+      vmcase(OP_BOR) {
+        op_bitwise(L, l_bor);
+        vmbreak;
+      }
+      vmcase(OP_BXOR) {
+        op_bitwise(L, l_bxor);
+        vmbreak;
+      }
+      vmcase(OP_SHR) {
+        op_bitwise(L, luaV_shiftr);
+        vmbreak;
+      }
+      vmcase(OP_SHL) {
+        op_bitwise(L, luaV_shiftl);
+        vmbreak;
+      }
+      vmcase(OP_MMBIN) {
+        Instruction pi = *(pc - 2);  /* original arith. expression */
+        TValue *rb = vRB(i);
+        TMS tm = (TMS)GETARG_C(i);
+        StkId result = RA(pi);
+        lua_assert(OP_ADD <= GET_OPCODE(pi) && GET_OPCODE(pi) <= OP_SHR);
+        Protect(luaT_trybinTM(L, s2v(ra), rb, result, tm));
+        vmbreak;
+      }
+      vmcase(OP_MMBINI) {
+        Instruction pi = *(pc - 2);  /* original arith. expression */
+        int imm = GETARG_sB(i);
+        TMS tm = (TMS)GETARG_C(i);
+        int flip = GETARG_k(i);
+        StkId result = RA(pi);
+        Protect(luaT_trybiniTM(L, s2v(ra), imm, flip, result, tm));
+        vmbreak;
+      }
+      vmcase(OP_MMBINK) {
+        Instruction pi = *(pc - 2);  /* original arith. expression */
+        TValue *imm = KB(i);
+        TMS tm = (TMS)GETARG_C(i);
+        int flip = GETARG_k(i);
+        StkId result = RA(pi);
+        Protect(luaT_trybinassocTM(L, s2v(ra), imm, flip, result, tm));
+        vmbreak;
+      }
+      vmcase(OP_UNM) {
+        TValue *rb = vRB(i);
+        lua_Number nb;
+        if (ttisinteger(rb)) {
+          lua_Integer ib = ivalue(rb);
+          setivalue(s2v(ra), intop(-, 0, ib));
+        }
+        else if (tonumberns(rb, nb)) {
+          setfltvalue(s2v(ra), luai_numunm(L, nb));
+        }
+        else
+          Protect(luaT_trybinTM(L, rb, rb, ra, TM_UNM));
+        vmbreak;
+      }
+      vmcase(OP_BNOT) {
+        TValue *rb = vRB(i);
+        lua_Integer ib;
+        if (tointegerns(rb, &ib)) {
+          setivalue(s2v(ra), intop(^, ~l_castS2U(0), ib));
+        }
+        else
+          Protect(luaT_trybinTM(L, rb, rb, ra, TM_BNOT));
+        vmbreak;
+      }
+      vmcase(OP_NOT) {
+        TValue *rb = vRB(i);
+        if (l_isfalse(rb))
+          setbtvalue(s2v(ra));
+        else
+          setbfvalue(s2v(ra));
+        vmbreak;
+      }
+      vmcase(OP_LEN) {
+        Protect(luaV_objlen(L, ra, vRB(i)));
+        vmbreak;
+      }
+      vmcase(OP_CONCAT) {
+        int n = GETARG_B(i);  /* number of elements to concatenate */
+        L->top = ra + n;  /* mark the end of concat operands */
+        ProtectNT(luaV_concat(L, n));
+        checkGC(L, L->top); /* 'luaV_concat' ensures correct top */
+        vmbreak;
+      }
+      vmcase(OP_CLOSE) {
+        Protect(luaF_close(L, ra, LUA_OK));
+        vmbreak;
+      }
+      vmcase(OP_TBC) {
+        /* create new to-be-closed upvalue */
+        halfProtect(luaF_newtbcupval(L, ra));
+        vmbreak;
+      }
+      vmcase(OP_JMP) {
+        dojump(ci, i, 0);
+        vmbreak;
+      }
+      vmcase(OP_EQ) {
+        int cond;
+        TValue *rb = vRB(i);
+        Protect(cond = luaV_equalobj(L, s2v(ra), rb));
+        docondjump();
+        vmbreak;
+      }
+      vmcase(OP_LT) {
+        op_order(L, l_lti, LTnum, lessthanothers);
+        vmbreak;
+      }
+      vmcase(OP_LE) {
+        op_order(L, l_lei, LEnum, lessequalothers);
+        vmbreak;
+      }
+      vmcase(OP_EQK) {
+        TValue *rb = KB(i);
+        /* basic types do not use '__eq'; we can use raw equality */
+        int cond = luaV_rawequalobj(s2v(ra), rb);
+        docondjump();
+        vmbreak;
+      }
+      vmcase(OP_EQI) {
+        int cond;
+        int im = GETARG_sB(i);
+        if (ttisinteger(s2v(ra)))
+          cond = (ivalue(s2v(ra)) == im);
+        else if (ttisfloat(s2v(ra)))
+          cond = luai_numeq(fltvalue(s2v(ra)), cast_num(im));
+        else
+          cond = 0;  /* other types cannot be equal to a number */
+        docondjump();
+        vmbreak;
+      }
+      vmcase(OP_LTI) {
+        op_orderI(L, l_lti, luai_numlt, 0, TM_LT);
+        vmbreak;
+      }
+      vmcase(OP_LEI) {
+        op_orderI(L, l_lei, luai_numle, 0, TM_LE);
+        vmbreak;
+      }
+      vmcase(OP_GTI) {
+        op_orderI(L, l_gti, luai_numgt, 1, TM_LT);
+        vmbreak;
+      }
+      vmcase(OP_GEI) {
+        op_orderI(L, l_gei, luai_numge, 1, TM_LE);
+        vmbreak;
+      }
+      vmcase(OP_TEST) {
+        int cond = !l_isfalse(s2v(ra));
+        docondjump();
+        vmbreak;
+      }
+      vmcase(OP_TESTSET) {
+        TValue *rb = vRB(i);
+        if (l_isfalse(rb) == GETARG_k(i))
+          pc++;
+        else {
+          setobj2s(L, ra, rb);
+          donextjump(ci);
+        }
+        vmbreak;
+      }
+      vmcase(OP_CALL) {
+        int b = GETARG_B(i);
+        int nresults = GETARG_C(i) - 1;
+        if (b != 0)  /* fixed number of arguments? */
+          L->top = ra + b;  /* top signals number of arguments */
+        /* else previous instruction set top */
+        ProtectNT(luaD_call(L, ra, nresults));
+        vmbreak;
+      }
+      vmcase(OP_TAILCALL) {
+        int b = GETARG_B(i);  /* number of arguments + 1 (function) */
+        int nparams1 = GETARG_C(i);
+        /* delat is virtual 'func' - real 'func' (vararg functions) */
+        int delta = (nparams1) ? ci->u.l.nextraargs + nparams1 : 0;
+        if (b != 0)
+          L->top = ra + b;
+        else  /* previous instruction set top */
+          b = cast_int(L->top - ra);
+        savepc(ci);  /* some calls here can raise errors */
+        if (TESTARG_k(i)) {
+          /* close upvalues from current call; the compiler ensures
+             that there are no to-be-closed variables here, so this
+             call cannot change the stack */
+          luaF_close(L, base, NOCLOSINGMETH);
+          lua_assert(base == ci->func + 1);
+        }
+        while (!ttisfunction(s2v(ra))) {  /* not a function? */
+          luaD_tryfuncTM(L, ra);  /* try '__call' metamethod */
+          b++;  /* there is now one extra argument */
+          checkstackp(L, 1, ra);
+        }
+        if (!ttisLclosure(s2v(ra))) {  /* C function? */
+          luaD_call(L, ra, LUA_MULTRET);  /* call it */
+          updatetrap(ci);
+          updatestack(ci);  /* stack may have been relocated */
+          ci->func -= delta;
+          luaD_poscall(L, ci, cast_int(L->top - ra));
+          return;
+        }
+        ci->func -= delta;
+        luaD_pretailcall(L, ci, ra, b);  /* prepare call frame */
+        goto tailcall;
+      }
+      vmcase(OP_RETURN) {
+        int n = GETARG_B(i) - 1;  /* number of results */
+        int nparams1 = GETARG_C(i);
+        if (n < 0)  /* not fixed? */
+          n = cast_int(L->top - ra);  /* get what is available */
+        savepc(ci);
+        if (TESTARG_k(i)) {  /* may there be open upvalues? */
+          if (L->top < ci->top)
+            L->top = ci->top;
+          luaF_close(L, base, LUA_OK);
+          updatetrap(ci);
+          updatestack(ci);
+        }
+        if (nparams1)  /* vararg function? */
+          ci->func -= ci->u.l.nextraargs + nparams1;
+        L->top = ra + n;  /* set call for 'luaD_poscall' */
+        luaD_poscall(L, ci, n);
+        return;
+      }
+      vmcase(OP_RETURN0) {
+        if (L->hookmask) {
+          L->top = ra;
+          halfProtectNT(luaD_poscall(L, ci, 0));  /* no hurry... */
+        }
+        else {  /* do the 'poscall' here */
+          int nres = ci->nresults;
+          L->ci = ci->previous;  /* back to caller */
+          L->top = base - 1;
+          while (nres-- > 0)
+            setnilvalue(s2v(L->top++));  /* all results are nil */
+        }
+        return;
+      }
+      vmcase(OP_RETURN1) {
+        if (L->hookmask) {
+          L->top = ra + 1;
+          halfProtectNT(luaD_poscall(L, ci, 1));  /* no hurry... */
+        }
+        else {  /* do the 'poscall' here */
+          int nres = ci->nresults;
+          L->ci = ci->previous;  /* back to caller */
+          if (nres == 0)
+            L->top = base - 1;  /* asked for no results */
+          else {
+            setobjs2s(L, base - 1, ra);  /* at least this result */
+            L->top = base;
+            while (--nres > 0)  /* complete missing results */
+              setnilvalue(s2v(L->top++));
+          }
+        }
+        return;
+      }
+      vmcase(OP_FORLOOP) {
+        if (ttisinteger(s2v(ra + 2))) {  /* integer loop? */
+          lua_Unsigned count = l_castS2U(ivalue(s2v(ra + 1)));
+          if (count > 0) {  /* still more iterations? */
+            lua_Integer step = ivalue(s2v(ra + 2));
+            lua_Integer idx = ivalue(s2v(ra));  /* internal index */
+            chgivalue(s2v(ra + 1), count - 1);  /* update counter */
+            idx = intop(+, idx, step);  /* add step to index */
+            chgivalue(s2v(ra), idx);  /* update internal index */
+            setivalue(s2v(ra + 3), idx);  /* and control variable */
+            pc -= GETARG_Bx(i);  /* jump back */
+          }
+        }
+        else if (floatforloop(ra))  /* float loop */
+          pc -= GETARG_Bx(i);  /* jump back */
+        updatetrap(ci);  /* allows a signal to break the loop */
+        vmbreak;
+      }
+      vmcase(OP_FORPREP) {
+        savestate(L, ci);  /* in case of errors */
+        if (forprep(L, ra))
+          pc += GETARG_Bx(i) + 1;  /* skip the loop */
+        vmbreak;
+      }
+      vmcase(OP_TFORPREP) {
+        /* create to-be-closed upvalue (if needed) */
+        halfProtect(luaF_newtbcupval(L, ra + 3));
+        pc += GETARG_Bx(i);
+        i = *(pc++);  /* go to next instruction */
+        lua_assert(GET_OPCODE(i) == OP_TFORCALL && ra == RA(i));
+        goto l_tforcall;
+      }
+      vmcase(OP_TFORCALL) {
+       l_tforcall:
+        /* 'ra' has the iterator function, 'ra + 1' has the state,
+           'ra + 2' has the control variable, and 'ra + 3' has the
+           to-be-closed variable. The call will use the stack after
+           these values (starting at 'ra + 4')
+        */
+        /* push function, state, and control variable */
+        memcpy(ra + 4, ra, 3 * sizeof(*ra));
+        L->top = ra + 4 + 3;
+        ProtectNT(luaD_call(L, ra + 4, GETARG_C(i)));  /* do the call */
+        updatestack(ci);  /* stack may have changed */
+        i = *(pc++);  /* go to next instruction */
+        lua_assert(GET_OPCODE(i) == OP_TFORLOOP && ra == RA(i));
+        goto l_tforloop;
+      }
+      vmcase(OP_TFORLOOP) {
+        l_tforloop:
+        if (!ttisnil(s2v(ra + 4))) {  /* continue loop? */
+          setobjs2s(L, ra + 2, ra + 4);  /* save control variable */
+          pc -= GETARG_Bx(i);  /* jump back */
+        }
+        vmbreak;
+      }
+      vmcase(OP_SETLIST) {
+        int n = GETARG_B(i);
+        unsigned int last = GETARG_C(i);
+        Table *h = hvalue(s2v(ra));
+        if (n == 0)
+          n = cast_int(L->top - ra) - 1;  /* get up to the top */
+        else
+          L->top = ci->top;  /* correct top in case of emergency GC */
+        last += n;
+        if (TESTARG_k(i)) {
+          last += GETARG_Ax(*pc) * (MAXARG_C + 1);
+          pc++;
+        }
+        if (last > luaH_realasize(h))  /* needs more space? */
+          luaH_resizearray(L, h, last);  /* preallocate it at once */
+        for (; n > 0; n--) {
+          TValue *val = s2v(ra + n);
+          setobj2t(L, &h->array[last - 1], val);
+          last--;
+          luaC_barrierback(L, obj2gco(h), val);
+        }
+        vmbreak;
+      }
+      vmcase(OP_CLOSURE) {
+        Proto *p = cl->p->p[GETARG_Bx(i)];
+        halfProtect(pushclosure(L, p, cl->upvals, base, ra));
+        checkGC(L, ra + 1);
+        vmbreak;
+      }
+      vmcase(OP_VARARG) {
+        int n = GETARG_C(i) - 1;  /* required results */
+        Protect(luaT_getvarargs(L, ci, ra, n));
+        vmbreak;
+      }
+      vmcase(OP_VARARGPREP) {
+        luaT_adjustvarargs(L, GETARG_A(i), ci, cl->p);
+        updatetrap(ci);
+        if (trap) {
+          luaD_hookcall(L, ci);
+          L->oldpc = pc + 1;  /* next opcode will be seen as a "new" line */
+        }
+        updatebase(ci);  /* function has new base after adjustment */
+        vmbreak;
+      }
+      vmcase(OP_EXTRAARG) {
+        lua_assert(0);
+        vmbreak;
+      }
+    }
+  }
+}
+
+/* }================================================================== */
diff --git a/test/external/lua-5.4.0/src/lvm.h b/test/external/lua-5.4.0/src/lvm.h
new file mode 100644
index 0000000..2d4ac16
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lvm.h
@@ -0,0 +1,134 @@
+/*
+** $Id: lvm.h $
+** Lua virtual machine
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lvm_h
+#define lvm_h
+
+
+#include "ldo.h"
+#include "lobject.h"
+#include "ltm.h"
+
+
+#if !defined(LUA_NOCVTN2S)
+#define cvt2str(o)	ttisnumber(o)
+#else
+#define cvt2str(o)	0	/* no conversion from numbers to strings */
+#endif
+
+
+#if !defined(LUA_NOCVTS2N)
+#define cvt2num(o)	ttisstring(o)
+#else
+#define cvt2num(o)	0	/* no conversion from strings to numbers */
+#endif
+
+
+/*
+** You can define LUA_FLOORN2I if you want to convert floats to integers
+** by flooring them (instead of raising an error if they are not
+** integral values)
+*/
+#if !defined(LUA_FLOORN2I)
+#define LUA_FLOORN2I		F2Ieq
+#endif
+
+
+/*
+** Rounding modes for float->integer coercion
+ */
+typedef enum {
+  F2Ieq,     /* no rounding; accepts only integral values */
+  F2Ifloor,  /* takes the floor of the number */
+  F2Iceil    /* takes the ceil of the number */
+} F2Imod;
+
+
+/* convert an object to a float (including string coercion) */
+#define tonumber(o,n) \
+	(ttisfloat(o) ? (*(n) = fltvalue(o), 1) : luaV_tonumber_(o,n))
+
+
+/* convert an object to a float (without string coercion) */
+#define tonumberns(o,n) \
+	(ttisfloat(o) ? ((n) = fltvalue(o), 1) : \
+	(ttisinteger(o) ? ((n) = cast_num(ivalue(o)), 1) : 0))
+
+
+/* convert an object to an integer (including string coercion) */
+#define tointeger(o,i) \
+  (ttisinteger(o) ? (*(i) = ivalue(o), 1) : luaV_tointeger(o,i,LUA_FLOORN2I))
+
+
+/* convert an object to an integer (without string coercion) */
+#define tointegerns(o,i) \
+  (ttisinteger(o) ? (*(i) = ivalue(o), 1) : luaV_tointegerns(o,i,LUA_FLOORN2I))
+
+
+#define intop(op,v1,v2) l_castU2S(l_castS2U(v1) op l_castS2U(v2))
+
+#define luaV_rawequalobj(t1,t2)		luaV_equalobj(NULL,t1,t2)
+
+
+/*
+** fast track for 'gettable': if 't' is a table and 't[k]' is present,
+** return 1 with 'slot' pointing to 't[k]' (position of final result).
+** Otherwise, return 0 (meaning it will have to check metamethod)
+** with 'slot' pointing to an empty 't[k]' (if 't' is a table) or NULL
+** (otherwise). 'f' is the raw get function to use.
+*/
+#define luaV_fastget(L,t,k,slot,f) \
+  (!ttistable(t)  \
+   ? (slot = NULL, 0)  /* not a table; 'slot' is NULL and result is 0 */  \
+   : (slot = f(hvalue(t), k),  /* else, do raw access */  \
+      !isempty(slot)))  /* result not empty? */
+
+
+/*
+** Special case of 'luaV_fastget' for integers, inlining the fast case
+** of 'luaH_getint'.
+*/
+#define luaV_fastgeti(L,t,k,slot) \
+  (!ttistable(t)  \
+   ? (slot = NULL, 0)  /* not a table; 'slot' is NULL and result is 0 */  \
+   : (slot = (l_castS2U(k) - 1u < hvalue(t)->alimit) \
+              ? &hvalue(t)->array[k - 1] : luaH_getint(hvalue(t), k), \
+      !isempty(slot)))  /* result not empty? */
+
+
+/*
+** Finish a fast set operation (when fast get succeeds). In that case,
+** 'slot' points to the place to put the value.
+*/
+#define luaV_finishfastset(L,t,slot,v) \
+    { setobj2t(L, cast(TValue *,slot), v); \
+      luaC_barrierback(L, gcvalue(t), v); }
+
+
+
+
+LUAI_FUNC int luaV_equalobj (lua_State *L, const TValue *t1, const TValue *t2);
+LUAI_FUNC int luaV_lessthan (lua_State *L, const TValue *l, const TValue *r);
+LUAI_FUNC int luaV_lessequal (lua_State *L, const TValue *l, const TValue *r);
+LUAI_FUNC int luaV_tonumber_ (const TValue *obj, lua_Number *n);
+LUAI_FUNC int luaV_tointeger (const TValue *obj, lua_Integer *p, F2Imod mode);
+LUAI_FUNC int luaV_tointegerns (const TValue *obj, lua_Integer *p,
+                                F2Imod mode);
+LUAI_FUNC int luaV_flttointeger (lua_Number n, lua_Integer *p, F2Imod mode);
+LUAI_FUNC void luaV_finishget (lua_State *L, const TValue *t, TValue *key,
+                               StkId val, const TValue *slot);
+LUAI_FUNC void luaV_finishset (lua_State *L, const TValue *t, TValue *key,
+                               TValue *val, const TValue *slot);
+LUAI_FUNC void luaV_finishOp (lua_State *L);
+LUAI_FUNC void luaV_execute (lua_State *L, CallInfo *ci);
+LUAI_FUNC void luaV_concat (lua_State *L, int total);
+LUAI_FUNC lua_Integer luaV_idiv (lua_State *L, lua_Integer x, lua_Integer y);
+LUAI_FUNC lua_Integer luaV_mod (lua_State *L, lua_Integer x, lua_Integer y);
+LUAI_FUNC lua_Number luaV_modf (lua_State *L, lua_Number x, lua_Number y);
+LUAI_FUNC lua_Integer luaV_shiftl (lua_Integer x, lua_Integer y);
+LUAI_FUNC void luaV_objlen (lua_State *L, StkId ra, const TValue *rb);
+
+#endif
diff --git a/test/external/lua-5.4.0/src/lzio.c b/test/external/lua-5.4.0/src/lzio.c
new file mode 100644
index 0000000..cd0a02d
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lzio.c
@@ -0,0 +1,68 @@
+/*
+** $Id: lzio.c $
+** Buffered streams
+** See Copyright Notice in lua.h
+*/
+
+#define lzio_c
+#define LUA_CORE
+
+#include "lprefix.h"
+
+
+#include <string.h>
+
+#include "lua.h"
+
+#include "llimits.h"
+#include "lmem.h"
+#include "lstate.h"
+#include "lzio.h"
+
+
+int luaZ_fill (ZIO *z) {
+  size_t size;
+  lua_State *L = z->L;
+  const char *buff;
+  lua_unlock(L);
+  buff = z->reader(L, z->data, &size);
+  lua_lock(L);
+  if (buff == NULL || size == 0)
+    return EOZ;
+  z->n = size - 1;  /* discount char being returned */
+  z->p = buff;
+  return cast_uchar(*(z->p++));
+}
+
+
+void luaZ_init (lua_State *L, ZIO *z, lua_Reader reader, void *data) {
+  z->L = L;
+  z->reader = reader;
+  z->data = data;
+  z->n = 0;
+  z->p = NULL;
+}
+
+
+/* --------------------------------------------------------------- read --- */
+size_t luaZ_read (ZIO *z, void *b, size_t n) {
+  while (n) {
+    size_t m;
+    if (z->n == 0) {  /* no bytes in buffer? */
+      if (luaZ_fill(z) == EOZ)  /* try to read more */
+        return n;  /* no more input; return number of missing bytes */
+      else {
+        z->n++;  /* luaZ_fill consumed first byte; put it back */
+        z->p--;
+      }
+    }
+    m = (n <= z->n) ? n : z->n;  /* min. between n and z->n */
+    memcpy(b, z->p, m);
+    z->n -= m;
+    z->p += m;
+    b = (char *)b + m;
+    n -= m;
+  }
+  return 0;
+}
+
diff --git a/test/external/lua-5.4.0/src/lzio.h b/test/external/lua-5.4.0/src/lzio.h
new file mode 100644
index 0000000..38f397f
--- /dev/null
+++ b/test/external/lua-5.4.0/src/lzio.h
@@ -0,0 +1,66 @@
+/*
+** $Id: lzio.h $
+** Buffered streams
+** See Copyright Notice in lua.h
+*/
+
+
+#ifndef lzio_h
+#define lzio_h
+
+#include "lua.h"
+
+#include "lmem.h"
+
+
+#define EOZ	(-1)			/* end of stream */
+
+typedef struct Zio ZIO;
+
+#define zgetc(z)  (((z)->n--)>0 ?  cast_uchar(*(z)->p++) : luaZ_fill(z))
+
+
+typedef struct Mbuffer {
+  char *buffer;
+  size_t n;
+  size_t buffsize;
+} Mbuffer;
+
+#define luaZ_initbuffer(L, buff) ((buff)->buffer = NULL, (buff)->buffsize = 0)
+
+#define luaZ_buffer(buff)	((buff)->buffer)
+#define luaZ_sizebuffer(buff)	((buff)->buffsize)
+#define luaZ_bufflen(buff)	((buff)->n)
+
+#define luaZ_buffremove(buff,i)	((buff)->n -= (i))
+#define luaZ_resetbuffer(buff) ((buff)->n = 0)
+
+
+#define luaZ_resizebuffer(L, buff, size) \
+	((buff)->buffer = luaM_reallocvchar(L, (buff)->buffer, \
+				(buff)->buffsize, size), \
+	(buff)->buffsize = size)
+
+#define luaZ_freebuffer(L, buff)	luaZ_resizebuffer(L, buff, 0)
+
+
+LUAI_FUNC void luaZ_init (lua_State *L, ZIO *z, lua_Reader reader,
+                                        void *data);
+LUAI_FUNC size_t luaZ_read (ZIO* z, void *b, size_t n);	/* read next n bytes */
+
+
+
+/* --------- Private Part ------------------ */
+
+struct Zio {
+  size_t n;			/* bytes still unread */
+  const char *p;		/* current position in buffer */
+  lua_Reader reader;		/* reader function */
+  void *data;			/* additional data */
+  lua_State *L;			/* Lua state (for reader) */
+};
+
+
+LUAI_FUNC int luaZ_fill (ZIO *z);
+
+#endif