add pic_parse

include/picrin.h

@@ -116,6 +116,7 @@ void pic_vec_extend_ip(pic_state *, struct pic_vector *, int);
 
 int pic_parse_file(pic_state *, FILE *file, pic_value *);
 int pic_parse_cstr(pic_state *, const char *, pic_value *);
+pic_value pic_parse(pic_state *, const char *);
 
 pic_value pic_apply(pic_state *pic, struct pic_proc *, pic_value);
 pic_value pic_apply_argv(pic_state *pic, struct pic_proc *, size_t, ...);

src/parse.y

@@ -431,3 +431,16 @@ pic_parse_cstr(pic_state *pic, const char *str, pic_value *v)
 
   return r;
 }
+
+pic_value
+pic_parse(pic_state *pic, const char *src)
+{
+  pic_value vs;
+  int r;
+
+  r = pic_parse_cstr(pic, src, &vs);
+  if (r != 1) {
+    return pic_undef_value();
+  }
+  return pic_car(pic, vs);
+}