// TODO(cpovirk): are we over-wrapping?
    this.delegate = Collections.unmodifiableSet(delegate);
  }

  @Override
  public UnmodifiableIterator<E> iterator() {
    return Iterators.unmodifiableIterator(delegate.iterator());
  }

  @Override
  public boolean contains(@Nullable Object object) {
    return object != null && delegate.contains(object);
  }

  @Override

      return standardIndexOf(element);
    }

    @Override
    public int lastIndexOf(Object element) {
      return standardLastIndexOf(element);
    }

    @Override
    public Iterator<T> iterator() {
      return listIterator();
    }

    @Override
    public ListIterator<T> listIterator() {
      return listIterator(0);
    }

    @Override

      return standardIndexOf(element);
    }

    @Override
    public int lastIndexOf(Object element) {
      return standardLastIndexOf(element);
    }

    @Override
    public Iterator<T> iterator() {
      return listIterator();
    }

    @Override
    public ListIterator<T> listIterator() {
      return listIterator(0);
    }

    @Override

  private ImmutableEnumMap(EnumMap<K, V> delegate) {
    this.delegate = delegate;
    checkArgument(!delegate.isEmpty());
  }

  @Override
  UnmodifiableIterator<K> keyIterator() {
    return Iterators.unmodifiableIterator(delegate.keySet().iterator());
  }

  @Override
  Spliterator<K> keySpliterator() {
    return delegate.keySet().spliterator();
  }

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

   * of the deque's iterators:
   *
   * <pre>{@code
   * Deque<E> deque = Queues.synchronizedDeque(Queues.<E>newArrayDeque());
   * ...
   * deque.add(element);  // Needn't be in synchronized block
   * ...
   * synchronized (deque) {  // Must synchronize on deque!
   *   Iterator<E> i = deque.iterator(); // Must be in synchronized block
   *   while (i.hasNext()) {

          .put(CharSink.class, NullByteSink.INSTANCE.asCharSink(UTF_8))
          // All collections are immutable empty. So safe for any type parameter.
          .put(Iterator.class, ImmutableSet.of().iterator())
          .put(PeekingIterator.class, Iterators.peekingIterator(ImmutableSet.of().iterator()))
          .put(ListIterator.class, ImmutableList.of().listIterator())
          .put(Iterable.class, ImmutableSet.of())

    return delegateList().equals(obj);
  }

  @Override
  public int hashCode() {
    return delegateList().hashCode();
  }

  @Override
  public UnmodifiableIterator<E> iterator() {
    return Iterators.unmodifiableIterator(delegateList().iterator());
  }

  @Override
  public boolean contains(@Nullable Object object) {
    return object != null && delegateList().contains(object);
  }

  @Override

   * of the deque's iterators:
   *
   * <pre>{@code
   * Deque<E> deque = Queues.synchronizedDeque(Queues.<E>newArrayDeque());
   * ...
   * deque.add(element);  // Needn't be in synchronized block
   * ...
   * synchronized (deque) {  // Must synchronize on deque!
   *   Iterator<E> i = deque.iterator(); // Must be in synchronized block
   *   while (i.hasNext()) {

   *     have the same bit length
   */
  public static HashCode combineOrdered(Iterable<HashCode> hashCodes) {
    Iterator<HashCode> iterator = hashCodes.iterator();
    checkArgument(iterator.hasNext(), "Must be at least 1 hash code to combine.");
    int bits = iterator.next().bits();
    byte[] resultBytes = new byte[bits / 8];
    for (HashCode hashCode : hashCodes) {
      byte[] nextBytes = hashCode.asBytes();

  }

  /**
   * Returns a sequential {@link Stream} of the remaining contents of {@code iterator}. Do not use
   * {@code iterator} directly after passing it to this method.
   */
  public static <T extends @Nullable Object> Stream<T> stream(Iterator<T> iterator) {
    return StreamSupport.stream(Spliterators.spliteratorUnknownSize(iterator, 0), false);
  }

  /**