* core/sig.g: grammar for method signatures in C.

core/sig.g

@@ -0,0 +1,101 @@
+#
+# sig.g
+# Method signature syntax (from C)
+#
+# (c) 2009 _why
+#
+
+%{
+#include <stdio.h>
+#include <stdlib.h>
+#include "potion.h"
+#include "internal.h"
+
+static int pos = 0;
+static char *input = NULL;
+static PNAsm * volatile sbuf;
+static Potion *P = 0;
+
+#define YY_INPUT(buf, result, max) { \
+  if (pos < strlen(input)) { \
+    result = max; \
+    if (pos + max > strlen(input)) \
+      result = (strlen(input) - pos); \
+    PN_MEMCPY_N(buf, input + pos, char, result + 1); \
+    pos += max; \
+  } else { \
+    result = 0; \
+  } \
+}
+
+#define YYSTYPE PN
+#define YYPARSE potion_sig_yyparse
+#define YYPARSEFROM potion_sig_yyparse_from
+
+%}
+
+sig = args+ end-of-file
+args = arg-list (sep arg-list)*
+arg-list = arg-set (optional arg-set)?
+         | optional arg-set
+arg-set = arg (comma arg)*
+
+utfw = [A-Za-z0-9_$@;`{}]
+     | '\304' [\250-\277]
+     | [\305-\337] [\200-\277]
+     | [\340-\357] [\200-\277] [\200-\277]
+     | [\360-\364] [\200-\277] [\200-\277] [\200-\277]
+name = < utfw+ > - { $$ = potion_str2(P, yytext, yyleng); }
+type = < ('s' | 'S' | 'n' | 'N' | 'b' | 'B' | 'k' | 't' | 'o' | 'O' | '-' | '&') > -
+       { $$ = PN_NUM(yytext[0]); }
+arg = n:name eq t:type { P->source = PN_PUSH(PN_PUSH(PN_PUSH(P->source, n), t), PN_NIL); }
+    | t:type           { P->source = PN_PUSH(P->source, t); }
+optional = '|' -       { P->source = PN_PUSH(P->source, PN_NUM('|')); }
+eq = '=' -
+comma = ',' -
+sep = '.' -            { P->source = PN_PUSH(P->source, PN_NUM('.')); }
+
+- = space*
+space = ' ' | '\f' | '\v' | '\t' | '\r' | '\n'
+end-of-file = !.
+
+%%
+
+PN potion_sig(Potion *PP, char *fmt) {
+  if (fmt == NULL) return PN_NIL; // no signature, arg check off
+  if (fmt[0] == '\0') return PN_FALSE; // empty signature, no args
+
+  P = PP;
+  pos = 0;
+  input = fmt;
+  P->source = PN_TUP0();
+  yypos = yylimit = 0;
+  if (!YYPARSE())
+    printf("** Syntax error!\n");
+  return P->source;
+}
+
+int potion_sig_find(Potion *P, PN cl, PN name)
+{
+  PN_SIZE idx = 0;
+  PN sig;
+  if (!PN_IS_CLOSURE(cl))
+    cl = potion_obj_get_call(P, cl);
+
+  if (!PN_IS_CLOSURE(cl))
+    return -1;
+
+  sig = PN_CLOSURE(cl)->sig;
+
+  if (!PN_IS_TUPLE(sig))
+    return -1;
+
+  PN_TUPLE_EACH(sig, i, v, {
+    if (v == PN_NUM(idx) || v == name)
+      return idx;
+    if (PN_IS_NUM(v))
+      idx++;
+  });
+
+  return -1;
+}