return result;
          }
        });
  }

  @Override
  ImmutableSet<K> createKeySet() {
    return ImmutableSet.unsafeDelegate(delegate.keySet());
  }

  @Override
  ImmutableCollection<V> createValues() {
    return ImmutableCollection.unsafeDelegate(delegate.values());
  }

  @Override
  public int size() {
    return delegate.size();
  }

  @Override

    do {
      delegate.add(checkNotNull(elements.next()));
    } while (elements.hasNext());

    return unsafeDelegate(delegate);
  }

  // Factory methods that skips the null checks on elements, only used when
  // the elements are known to be non-null.
  static <E> ImmutableSet<E> unsafeDelegate(Set<E> delegate) {
    switch (delegate.size()) {
      case 0:
        return of();
      case 1:

   * where this collection's elements end.
   */
  int internalArrayEnd() {
    throw new UnsupportedOperationException();
  }

  static <E> ImmutableCollection<E> unsafeDelegate(Collection<E> delegate) {
    return new ForwardingImmutableCollection<E>(delegate);
  }

  boolean isPartialView() {
    return false;
  }