}

  @Override
  public ContiguousSet<C> headSet(C toElement) {
    return headSetImpl(checkNotNull(toElement), false);
  }

  /**
   * @since 12.0
   */
  @GwtIncompatible // NavigableSet
  @Override
  public ContiguousSet<C> headSet(C toElement, boolean inclusive) {
    return headSetImpl(checkNotNull(toElement), inclusive);
  }

  @Override

  @Override
  public @Nullable E higher(E element) {
    int index = tailIndex(element, false);
    return (index == size()) ? null : elements.get(index);
  }

  @Override
  ImmutableSortedSet<E> headSetImpl(E toElement, boolean inclusive) {
    return getSubSet(0, headIndex(toElement, inclusive));
  }

  int headIndex(E toElement, boolean inclusive) {

  }

  @Override
  public ContiguousSet<C> headSet(C toElement) {
    return headSetImpl(checkNotNull(toElement), false);
  }

  /**
   * @since 12.0
   */
  @GwtIncompatible // NavigableSet
  @Override
  public ContiguousSet<C> headSet(C toElement, boolean inclusive) {
    return headSetImpl(checkNotNull(toElement), inclusive);
  }

  @Override

  }

  @Override
  public Range<C> range(BoundType lowerBoundType, BoundType upperBoundType) {
    throw new NoSuchElementException();
  }

  @Override
  ContiguousSet<C> headSetImpl(C toElement, boolean inclusive) {
    return this;
  }

  @Override
  ContiguousSet<C> subSetImpl(
      C fromElement, boolean fromInclusive, C toElement, boolean toInclusive) {
    return this;
  }

    return range.isConnected(other)
        ? ContiguousSet.create(range.intersection(other), domain)
        : new EmptyContiguousSet<C>(domain);
  }

  @Override
  ContiguousSet<C> headSetImpl(C toElement, boolean inclusive) {
    return intersectionInCurrentDomain(Range.upTo(toElement, BoundType.forBoolean(inclusive)));
  }

  @Override

        }
      };
    }

    ImmutableSortedSet<C> subSet(Range<C> range) {
      return subRangeSet(range).asSet(domain);
    }

    @Override
    ImmutableSortedSet<C> headSetImpl(C toElement, boolean inclusive) {
      return subSet(Range.upTo(toElement, BoundType.forBoolean(inclusive)));
    }

    @Override
    ImmutableSortedSet<C> subSetImpl(