@Override
  @GwtIncompatible // NavigableSet
  ImmutableSortedSet<C> createDescendingSet() {
    return new DescendingImmutableSortedSet<>(this);
  }

  /** Returns a shorthand representation of the contents such as {@code "[1..100]"}. */
  @Override
  public String toString() {
    return range().toString();
  }

  /**
   * Not supported. {@code ContiguousSet} instances are constructed with {@link #create}. This

  @Override
  @GwtIncompatible // NavigableSet
  ImmutableSortedSet<C> createDescendingSet() {
    return new DescendingImmutableSortedSet<>(this);
  }

  /** Returns a shorthand representation of the contents such as {@code "[1..100]"}. */
  @Override
  public String toString() {
    return range().toString();
  }

  /**
   * Not supported. {@code ContiguousSet} instances are constructed with {@link #create}. This