public override void Visit(CycleItemNode node)
 {
   BeginNonTextNode();
   AppendNode(new CycleItemNode(node.Index));
   EndNonTextNode();
 }
 public virtual void Visit(CycleItemNode node)
 {
     throw new InvalidOperationException();
 }
 public override void Visit(CycleItemNode node)
 {
     result.Append(currentCycleItem[node.Index]);
 }