@Override
  public UnmodifiableIterator<C> descendingIterator() {
    return new AbstractSequentialIterator<C>(last()) {
      final C first = first();

      @Override
      protected @Nullable C computeNext(C previous) {
        return equalsOrThrow(previous, first) ? null : domain.previous(previous);
      }
    };
  }

   * the first are ignored.
   */
  public static <E> ImmutableSet<E> of(E e1, E e2, E e3, E e4, E e5) {
    return new RegularSetBuilderImpl<E>(5).add(e1).add(e2).add(e3).add(e4).add(e5).review().build();
  }

  /**
   * Returns an immutable set containing the given elements, minus duplicates, in the order each was

 * offering expected O(n + k log k) performance (worst case O(n log k)) for n calls to {@link
 * #offer} and a call to {@link #topK}, with O(k) memory. In comparison, quickselect has the same
 * asymptotics but requires O(n) memory, and a {@code PriorityQueue} implementation takes O(n log
 * k). In benchmarks, this implementation performs at least as well as either implementation, and
 * degrades more gracefully for worst-case input.
 *

    int len = sequence.length();
    int first;
    int last;

    for (first = 0; first < len; first++) {
      if (!matches(sequence.charAt(first))) {
        break;
      }
    }
    for (last = len - 1; last > first; last--) {
      if (!matches(sequence.charAt(last))) {
        break;
      }
    }

    return sequence.subSequence(first, last + 1).toString();
  }

  /**

          node.setNext(oldHead);
          if (casWaiters(oldHead, node)) {
            while (true) {
              OverflowAvoidingLockSupport.parkNanos(this, remainingNanos);
              // Check interruption first, if we woke up due to interruption we need to honor that.
              if (Thread.interrupted()) {
                removeWaiter(node);
                throw new InterruptedException();
              }

          node.setNext(oldHead);
          if (casWaiters(oldHead, node)) {
            while (true) {
              OverflowAvoidingLockSupport.parkNanos(this, remainingNanos);
              // Check interruption first, if we woke up due to interruption we need to honor that.
              if (Thread.interrupted()) {
                removeWaiter(node);
                throw new InterruptedException();
              }

   * as a false predicate is found.
   *
   * <p><b>Discouraged:</b> Prefer using {@code first.and(second)}.
   */
  public static <T extends @Nullable Object> Predicate<T> and(
      Predicate<? super T> first, Predicate<? super T> second) {
    return new AndPredicate<>(Predicates.<T>asList(checkNotNull(first), checkNotNull(second)));
  }

  /**

    if (!elements.hasNext()) {
      return of();
    }
    E first = elements.next();
    if (!elements.hasNext()) {
      // TODO: Remove "ImmutableSet.<E>" when eclipse bug is fixed.
      return ImmutableSet.<E>of(first);
    }

    Set<E> delegate = Sets.newLinkedHashSet();
    delegate.add(checkNotNull(first));
    do {
      delegate.add(checkNotNull(elements.next()));

   * will remember the first duplicate key we encountered. All later calls to buildOrThrow() can
   * mention that key with its values. Further duplicates might be added in the meantime but since
   * builders only ever accumulate entries it will always be valid to throw from buildOrThrow() with
   * the first duplicate.
   */

   *
   * @param first the first element
   * @param rest an array of additional elements, possibly empty
   * @return an unmodifiable list containing the specified elements
   */
  public static <E extends @Nullable Object> List<E> asList(@ParametricNullness E first, E[] rest) {
    return new OnePlusArrayList<>(first, rest);
  }

  /**