initial commit

1 files changed, 98 insertions, 0 deletions

diff --git a/repl.c b/repl.c
new file mode 100644
index 0000000..5a22bff
--- /dev/null
+++ b/repl.c
@@ -0,0 +1,98 @@
+#include "pez.h"
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <readline/readline.h>
+#include <readline/history.h>
+
+#define CHECK(x) do {                            \
+    if (!(x)) {                                  \
+        fprintf(stderr, "%s\n", pez_geterr(cx)); \
+        assert(!#x);                             \
+    }                                            \
+} while (0)
+
+static bool
+printtop(PezContext *cx) {
+    assert(pez_top(cx) >= 2);
+    return
+        pez_push(cx, 0) // printf was stored here
+     && pez_pushstring(cx, "%a", 2)
+     && pez_push(cx, -3)
+     && pez_apply(cx, 2)
+     && (pez_pop(cx), pez_pop(cx), 1);
+}
+
+static void
+help(void)
+{
+    printf("Usage: pez [OPTION]... [FILE] [ARG]...\n"
+           "With no FILE, enter repl.\n"
+           "\n"
+           "  -h, --help    show this help message\n"
+           "  -db           debug: print bytecode\n"
+           "\n");    
+}
+
+int
+main(int argc, char **argv) {
+    PezContext *cx = pez_new(NULL, NULL);
+    FILE *fp = NULL;
+    int i, ret = 0;
+
+    for (i = 1; i < argc; ++i) {
+        const char *arg = argv[i];
+        if (*arg == '-') {
+            if (!strcmp(arg, "-h") || !strcmp(arg, "--help")) {
+                help();
+                goto Bye;
+            } else if (arg[1] == 'd') {
+                pez_debug(cx, arg + 2);
+            } else {
+                printf("pez: Invalid option '%s'\n", arg);
+                help();
+                ret = 1;
+                goto Bye;
+            }
+        } else {
+            fp = fopen(arg, "r");
+            if (!fp) {
+                perror(arg);
+                ret = 1;
+                goto Bye;
+            }
+            break;
+        }
+    }
+
+    if (!fp) {
+        char *src;
+        using_history();
+        CHECK(pez_pushglobal(cx, "printf"));
+
+        while ((src = readline("> "))) {
+            add_history(src);
+            if (!pez_eval_str(cx, "<repl>", src)) {
+                fprintf(stderr, "error: %s\n", pez_geterr(cx));
+            } else {
+                assert(pez_top(cx) == 2);
+                CHECK(printtop(cx));
+                printf("\n");
+            }
+            free(src);
+        }
+    } else {
+        if (!pez_eval_file(cx, argv[i], fp)) {
+            fprintf(stderr, "error: %s\n", pez_geterr(cx));
+            ret = 1;
+            goto Bye;
+        }
+        assert(pez_top(cx) == 1);
+    }
+Bye:
+    if (fp) {
+        fclose(fp);
+    }
+    pez_del(cx); 
+    return ret;
+}