*/
    assertThat(ImmutableDoubleArray.copyOf(new double[0]))
        .isSameInstanceAs(ImmutableDoubleArray.of());
  }

  public void testCopyOf_array_nonempty() {
    double[] array = new double[] {0, 1, 3};
    ImmutableDoubleArray iia = ImmutableDoubleArray.copyOf(array);
    array[2] = 2;
    assertThat(iia.asList()).containsExactly(0.0, 1.0, 3.0).inOrder();
  }

     */
    assertThat(ImmutableLongArray.copyOf(new long[0])).isSameInstanceAs(ImmutableLongArray.of());
  }

  public void testCopyOf_array_nonempty() {
    long[] array = new long[] {0, 1, 3};
    ImmutableLongArray iia = ImmutableLongArray.copyOf(array);
    array[2] = 2;
    assertThat(iia.asList()).containsExactly(0L, 1L, 3L).inOrder();
  }

     */
    assertThat(ImmutableLongArray.copyOf(new long[0])).isSameInstanceAs(ImmutableLongArray.of());
  }

  public void testCopyOf_array_nonempty() {
    long[] array = new long[] {0, 1, 3};
    ImmutableLongArray iia = ImmutableLongArray.copyOf(array);
    array[2] = 2;
    assertThat(iia.asList()).containsExactly(0L, 1L, 3L).inOrder();
  }

     */
    assertThat(ImmutableIntArray.copyOf(new int[0])).isSameInstanceAs(ImmutableIntArray.of());
  }

  public void testCopyOf_array_nonempty() {
    int[] array = new int[] {0, 1, 3};
    ImmutableIntArray iia = ImmutableIntArray.copyOf(array);
    array[2] = 2;
    assertThat(iia.asList()).containsExactly(0, 1, 3).inOrder();
  }

     */
    assertThat(ImmutableDoubleArray.copyOf(new double[0]))
        .isSameInstanceAs(ImmutableDoubleArray.of());
  }

  public void testCopyOf_array_nonempty() {
    double[] array = new double[] {0, 1, 3};
    ImmutableDoubleArray iia = ImmutableDoubleArray.copyOf(array);
    array[2] = 2;
    assertThat(iia.asList()).containsExactly(0.0, 1.0, 3.0).inOrder();
  }

    return Platform.nullToEmpty(string);
  }

  /**
   * Returns the given string if it is nonempty; {@code null} otherwise.
   *
   * @param string the string to test and possibly return
   * @return {@code string} itself if it is nonempty; {@code null} if it is empty or null
   */
  @CheckForNull
  public static String emptyToNull(@CheckForNull String string) {

     */
    assertThat(ImmutableIntArray.copyOf(new int[0])).isSameInstanceAs(ImmutableIntArray.of());
  }

  public void testCopyOf_array_nonempty() {
    int[] array = new int[] {0, 1, 3};
    ImmutableIntArray iia = ImmutableIntArray.copyOf(array);
    array[2] = 2;
    assertThat(iia.asList()).containsExactly(0, 1, 3).inOrder();
  }

    return Platform.nullToEmpty(string);
  }

  /**
   * Returns the given string if it is nonempty; {@code null} otherwise.
   *
   * @param string the string to test and possibly return
   * @return {@code string} itself if it is nonempty; {@code null} if it is empty or null
   */
  @CheckForNull
  public static String emptyToNull(@CheckForNull String string) {

    }

    return empty
        ? new EmptyContiguousSet<C>(domain)
        : new RegularContiguousSet<C>(effectiveRange, domain);
  }

  /**
   * Returns a nonempty contiguous set containing all {@code int} values from {@code lower}
   * (inclusive) to {@code upper} (inclusive). (These are the same values contained in {@code
   * Range.closed(lower, upper)}.)
   *

/**
 * A collection that maps keys to values, similar to {@link Map}, but in which each key may be
 * associated with <i>multiple</i> values. You can visualize the contents of a multimap either as a
 * map from keys to <i>nonempty</i> collections of values:
 *
 * <ul>
 *   <li>a → 1, 2
 *   <li>b → 3
 * </ul>
 *
 * ... or as a single "flattened" collection of key-value pairs:
 *
 * <ul>
 *   <li>a → 1
 *   <li>a → 2