| Id s -> Printf.sprintf "ID(%s)" s
| Symbol (s, i) -> Printf.sprintf "SYMBOL(%s,%d)" s i
| Num i -> Printf.sprintf "NUM(instance %d)" i
| Id s -> Printf.sprintf "ID(%s)" s
| Symbol (s, i) -> Printf.sprintf "SYMBOL(%s,%d)" s i
| Num i -> Printf.sprintf "NUM(instance %d)" i