*/
    public ImmutableSet<@NonNull E> immutableCopy() {
      // Not using ImmutableSet.copyOf() to avoid iterating thrice (isEmpty, size, iterator).
      int maxSize = maxSize();
      if (maxSize == 0) {
        return ImmutableSet.of();
      }
      ImmutableSet.Builder<@NonNull E> builder = ImmutableSet.builderWithExpectedSize(maxSize);
      for (E element : this) {

  }

  private static void assertHasArrayInterfaces(TypeToken<?> arrayType) {
    assertEquals(arrayInterfaces(), ImmutableSet.copyOf(arrayType.getGenericInterfaces()));
  }

  private static ImmutableSet<TypeToken<?>> arrayInterfaces() {
    ImmutableSet.Builder<TypeToken<?>> builder = ImmutableSet.builder();
    for (Class<?> interfaceType : Object[].class.getInterfaces()) {
      builder.add(TypeToken.of(interfaceType));

  }

  private static void assertHasArrayInterfaces(TypeToken<?> arrayType) {
    assertEquals(arrayInterfaces(), ImmutableSet.copyOf(arrayType.getGenericInterfaces()));
  }

  private static ImmutableSet<TypeToken<?>> arrayInterfaces() {
    ImmutableSet.Builder<TypeToken<?>> builder = ImmutableSet.builder();
    for (Class<?> interfaceType : Object[].class.getInterfaces()) {
      builder.add(TypeToken.of(interfaceType));

   *
   * <p>The {@link Iterable} equivalent of this method is {@link ImmutableSet#of()}.
   */
  static <T extends @Nullable Object> UnmodifiableIterator<T> emptyIterator() {
    return emptyListIterator();
  }

  /**
   * Returns the empty iterator.
   *
   * <p>The {@link Iterable} equivalent of this method is {@link ImmutableSet#of()}.
   */
  // Casting to any type is safe since there are no actual elements.