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+.. Metalang99 documentation master file, created by
+   sphinx-quickstart on Mon Jan  4 08:10:23 2021.
+   You can adapt this file completely to your liking, but it should at least
+   contain the root `toctree` directive.
+
+The Metalang99 Standard Library
+===============================
+
+The Metalang99 standard library exports a set of macros implemented using the `Metalang99 metalanguage`_.
+
+Definitions
+-----------
+
+ - A plain macro is a macro whose result can be computed only by preprocessor expansion.
+
+ - A Metalang99-compliant macro is a macro called through `ML99_call`/`ML99_callUneval`, directly or indirectly. To compute its result, the Metalang99 interpreter is needed.
+
+ - A desugaring macro is a convenience macro `X(params...)` which expands to `ML99_call(X, params...)` so that you can invoke `X` as `X(v(1), v(2), v(3))`. Desugaring macros are provided for all public Metalang99-compliant macros.
+
+Naming conventions
+------------------
+
+ - Plain macros follow the `SCREAMING_CASE` convention.
+ - Metalang99-compliant macros follow the `camelCase` convention.
+ - Macros denoting language terms (defined by `lang.h`) follow the `camelCase` convention.
+
+Sometimes, there exist two versions of the same macro: one is plain, and the other is Metalang99-compliant. For example, here are two complete metaprograms, one using `ML99_untuple` and the second one using `ML99_UNTUPLE`:
+
+.. code:: c
+
+   ML99_EVAL(ML99_untuple(v((1, 2, 3))))
+
+.. code:: c
+
+   ML99_UNTUPLE((1, 2, 3))
+
+Both metaprograms result in `1, 2, 3`.
+
+Version manipulation macros
+---------------------------
+
+*The following macros are defined in metalang99.h*.
+
+`ML99_MAJOR`, `ML99_MINOR`, and `ML99_PATCH` denote the major, the minor, and the patch version numbers, respectively.
+
+`ML99_VERSION_COMPATIBLE(x, y, z)` and `ML99_VERSION_EQ(x, y, z)` are function-like macros that expand to a constant boolean expression:
+
+ - The former holds iff the current Metalang99 version is at least vx.y.z in a `SemVer`_-compatible way. Thus, if the current version is v1.2.3, then `ML99_VERSION_COMPATIBLE` will hold for v1.2.3, v1.2.6, v1.6.0, but not for v2.5.0 or v3.0.0.
+ - The latter one holds iff the version is exactly vx.y.z.
+
+These macros can be used as follows:
+
+.. code:: c
+
+    #if !ML99_VERSION_COMPATIBLE(1, 2, 3)
+    #error Please, update your Metalang99 to v1.2.3 or higher!
+    #endif
+
+.. toctree::
+   :hidden:
+
+   lang
+   choice
+   tuple
+   variadics
+   list
+   seq
+   either
+   maybe
+   nat
+   ident
+   bool
+   util
+   assert
+   gen
+   stmt
+
+Contents
+====================================
+
+ - `lang.h`_ - The core metalanguage.
+ - `choice.h`_ - Choice types: `(tag, ...)`.
+ - `tuple.h`_ - Tuples: `(x, y, z)`.
+ - `variadics.h`_ - Variadic arguments: `x, y, z`.
+ - `list.h`_ - Cons-lists.
+ - `seq.h`_ - Sequences: `(x)(y)(z)`.
+ - `either.h`_ - A choice type with two cases.
+ - `maybe.h`_ - An optional value.
+ - `nat.h`_ - Natural numbers: [0; 255].
+ - `ident.h`_ - Identifiers: `[a-zA-Z0-9_]+`.
+ - `bool.h`_ - Boolean algebra.
+ - `util.h`_ - Utilitary stuff.
+ - `assert.h`_ - Static assertions.
+ - `gen.h`_ - Support for C language constructions.
+ - `stmt.h`_ - Statement chaining.
+
+Indices and tables
+====================================
+
+* :ref:`genindex`
+* :ref:`search`
+
+.. _Metalang99 metalanguage: https://github.com/hirrolot/metalang99
+.. _SemVer: https://semver.org/
+
+.. _lang.h: lang.html
+.. _choice.h: choice.html
+.. _tuple.h: tuple.html
+.. _variadics.h: variadics.html
+.. _list.h: list.html
+.. _seq.h: seq.html
+.. _either.h: either.html
+.. _maybe.h: maybe.html
+.. _nat.h: nat.html
+.. _ident.h: ident.html
+.. _bool.h: bool.html
+.. _util.h: util.html
+.. _assert.h: assert.html
+.. _gen.h: gen.html
+.. _stmt.h: stmt.html