*/
  Collection<V> wrapCollection(@ParametricNullness K key, Collection<V> collection) {
    return new WrappedCollection(key, collection, null);
  }

  final List<V> wrapList(
      @ParametricNullness K key, List<V> list, @Nullable WrappedCollection ancestor) {
    return (list instanceof RandomAccess)
        ? new RandomAccessWrappedList(key, list, ancestor)