code: static boolean isLoopStructure(Node n) {
      switch (n.getToken()) {
        case FOR:
        case FOR_IN:
        case FOR_OF:
        case FOR_AWAIT_OF:
        case DO:
        case WHILE:
          return true;
        default:
          return false;
      }
    }
docs: Determines whether the given node is a FOR, DO, or WHILE node.