*/
  public static <E> ImmutableList<E> of(E e1, E e2, E e3, E e4) {
    return construct(e1, e2, e3, e4);
  }

  /**
   * Returns an immutable list containing the given elements, in order.
   *
   * @throws NullPointerException if any element is null
   */
  public static <E> ImmutableList<E> of(E e1, E e2, E e3, E e4, E e5) {
    return construct(e1, e2, e3, e4, e5);
  }

  /**

  public void testAddAll_nonEmptyList() {
    assertTrue(getMultiset().addAll(asList(e3(), e4(), e3())));
    expectAdded(e3(), e4(), e3());
  }

  @CollectionFeature.Require(SUPPORTS_ADD)
  public void testAddAll_nonEmptyMultiset() {
    assertTrue(getMultiset().addAll(getSubjectGenerator().create(e3(), e4(), e3())));
    expectAdded(e3(), e4(), e3());
  }

  // TODO: rename e3, e4 => missing1, missing2
  private final E e0;
  private final E e1;
  private final E e2;
  private final E e3;
  private final E e4;

  public SampleElements(E e0, E e1, E e2, E e3, E e4) {
    this.e0 = e0;
    this.e1 = e1;
    this.e2 = e2;
    this.e3 = e3;
    this.e4 = e4;
  }

  @Override
  public Iterator<E> iterator() {

  public static <E> ImmutableSet<E> of(E e1, E e2, E e3, E e4) {
    return create(e1, e2, e3, e4);
  }

  @SuppressWarnings("unchecked")
  public static <E> ImmutableSet<E> of(E e1, E e2, E e3, E e4, E e5) {
    return create(e1, e2, e3, e4, e5);
  }

  @SuppressWarnings("unchecked")
  public static <E> ImmutableSet<E> of(E e1, E e2, E e3, E e4, E e5, E e6, E... others) {
    int size = others.length + 6;

  // TODO: rename e3, e4 => missing1, missing2
  private final E e0;
  private final E e1;
  private final E e2;
  private final E e3;
  private final E e4;

  public SampleElements(E e0, E e1, E e2, E e3, E e4) {
    this.e0 = e0;
    this.e1 = e1;
    this.e2 = e2;
    this.e3 = e3;
    this.e4 = e4;
  }

  @Override
  public Iterator<E> iterator() {

  public static <E> ImmutableList<E> of(E e1, E e2, E e3, E e4) {
    return new RegularImmutableList<E>(ImmutableList.<E>nullCheckedList(e1, e2, e3, e4));
  }

  public static <E> ImmutableList<E> of(E e1, E e2, E e3, E e4, E e5) {
    return new RegularImmutableList<E>(ImmutableList.<E>nullCheckedList(e1, e2, e3, e4, e5));
  }

  public static <E> ImmutableList<E> of(E e1, E e2, E e3, E e4, E e5, E e6) {

    return ImmutableSet.of(e1, e2, e3, e4);
  }

  @Override
  protected <E extends Comparable<? super E>> Set<E> of(E e1, E e2, E e3, E e4, E e5) {
    return ImmutableSet.of(e1, e2, e3, e4, e5);
  }

  @Override
  protected <E extends Comparable<? super E>> Set<E> of(
      E e1, E e2, E e3, E e4, E e5, E e6, E... rest) {

    return ImmutableSet.of(e1, e2, e3, e4);
  }

  @Override
  protected <E extends Comparable<? super E>> Set<E> of(E e1, E e2, E e3, E e4, E e5) {
    return ImmutableSet.of(e1, e2, e3, e4, e5);
  }

  @Override
  protected <E extends Comparable<? super E>> Set<E> of(
      E e1, E e2, E e3, E e4, E e5, E e6, E... rest) {

                    return symmetricDifference(
                        newHashSet(elements[0], elements[1], samples().e3(), samples().e4()),
                        newHashSet(elements[2], samples().e3(), samples().e4()));
                  }
                })
            .named("set ^ set")
            .withFeatures(CollectionSize.SEVERAL, CollectionFeature.ALLOWS_NULL_VALUES)

   *
   * @throws NullPointerException if any element is null
   */
  public static <E extends Comparable<? super E>> ImmutableSortedMultiset<E> of(
      E e1, E e2, E e3, E e4) {
    return copyOf(Ordering.natural(), Arrays.asList(e1, e2, e3, e4));
  }

  /**
   * Returns an immutable sorted multiset containing the given elements sorted by their natural
   * ordering.
   *