code: private Node delegate(Tag tag, Object value) {
          Objects.requireNonNull(tag);
          Node node = delegate(value);
          node.setTag(tag);
          return node;
      }
docs: Delegate the representation of {@code value} and apply the specified
  {@link Tag}
  
  @param tag   the tag
  @param value the value to represent
  
  @return the representation created by the delegate