assertThat(iia0.subArray(0, 0)).isSameInstanceAs(ImmutableLongArray.of());
    assertThat(iia1.subArray(0, 0)).isSameInstanceAs(ImmutableLongArray.of());
    assertThat(iia1.subArray(1, 1)).isSameInstanceAs(ImmutableLongArray.of());
    assertThat(iia1.subArray(0, 1).asList()).containsExactly(5L);
    assertThat(iia3.subArray(0, 2).asList()).containsExactly(5L, 25L).inOrder();

   *
   * <p><b>Performance note:</b> The returned array has the same full memory footprint as this one
   * does (no actual copying is performed). To reduce memory usage, use {@code subArray(start,
   * end).trimmed()}.
   */
  public ImmutableLongArray subArray(int startIndex, int endIndex) {
    Preconditions.checkPositionIndexes(startIndex, endIndex, length());
    return startIndex == endIndex
        ? EMPTY

   *
   * <p><b>Performance note:</b> The returned array has the same full memory footprint as this one
   * does (no actual copying is performed). To reduce memory usage, use {@code subArray(start,
   * end).trimmed()}.
   */
  public ImmutableIntArray subArray(int startIndex, int endIndex) {
    Preconditions.checkPositionIndexes(startIndex, endIndex, length());
    return startIndex == endIndex
        ? EMPTY