@Override
  public @NotNull List<LighterASTNode> getChildren(final @NotNull LighterASTNode parent) {
    final Ref<LighterASTNode[]> into = new Ref<>();
    final int numKids = myTreeStructure.getChildren(parent, into);
    if (numKids == 0) {
      return ContainerUtil.emptyList();
    }
    LighterASTNode[] elements = into.get();
    assert elements != null : myTreeStructure +" ("+parent+")";
    return new LighterASTNodeList(numKids, elements);
  }
@Override
  public @NotNull List<LighterASTNode> getChildren(final @NotNull LighterASTNode parent)