Expand C tokens and parser expression support

base.c

@@ -1,3 +1,18 @@
+#define panicf(...) base_panicf(__FILE__, __LINE__, __VA_ARGS__)
+
+_Noreturn
+void base_panicf(char *file, int line, const char *fmt, ...) {
+    fprintf(stderr, "%s:%d", file, line);
+    va_list args;
+    va_start(args, fmt);
+    vfprintf(stderr, fmt, args);
+    va_end(args);
+    fprintf(stderr, "\n");
+    fflush(stderr);
+    fflush(stdout);
+    exit(1);
+}
+
 #define Vec(T) struct { T *data; int len; int cap; }
 typedef Vec(void) VecVoid;