Properly evaluate the closing loop token

c/meltdown.c

@@ -45,7 +45,7 @@ uint16_t compile(const char *prog, uint8_t *tape, uint16_t tape_len, uint8_t **i
 
       traveled = compile(prog + 1, tape, tape_len, idx, should_eval);
     } else if(*prog == ']') {
-      if(**idx > 0) {
+      if(eval && **idx > 0) {
         return 0;
       } else {
         return elapsed + 1;