code: private static boolean hasBlockScopedVarsFollowing(Node start) {
      for (Node n = start.getNext(); n != null; n = n.getNext()) {
        if (n.isLet() || n.isConst()) {
          return true;
        }
      }
      return false;
    }
docs: Detect any block-scoped declarations that are younger siblings of the given starting point.
  
  @param start The start point