@GwtIncompatible
abstract class AbstractRangeSet<C extends Comparable> implements RangeSet<C> {
  AbstractRangeSet() {}

  @Override
  public boolean contains(C value) {
    return rangeContaining(value) != null;
  }

  @Override
  public abstract @Nullable Range<C> rangeContaining(C value);

  @Override
  public boolean isEmpty() {
    return asRanges().isEmpty();
  }

  @Override
  public void add(Range<C> range) {

@GwtIncompatible
abstract class AbstractRangeSet<C extends Comparable> implements RangeSet<C> {
  AbstractRangeSet() {}

  @Override
  public boolean contains(C value) {
    return rangeContaining(value) != null;
  }

  @Override
  public abstract @Nullable Range<C> rangeContaining(C value);

  @Override
  public boolean isEmpty() {
    return asRanges().isEmpty();
  }

  @Override
  public void add(Range<C> range) {

  /**
   * Returns the unique range from this range set that {@linkplain Range#contains contains} {@code
   * value}, or {@code null} if this range set does not contain {@code value}.
   */
  @Nullable Range<C> rangeContaining(C value);

  /**
   * Returns {@code true} if there exists a non-empty range enclosed by both a member range in this
   * range set and the specified range. This is equivalent to calling {@code