List<LighterASTNode> (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); }