boolean fromInclusive,
        @ParametricNullness K toKey,
        boolean toInclusive) {
      return asMap(set.subSet(fromKey, fromInclusive, toKey, toInclusive), function);
    }

    @Override
    public NavigableMap<K, V> headMap(@ParametricNullness K toKey, boolean inclusive) {
      return asMap(set.headSet(toKey, inclusive), function);
    }

    @Override

        boolean fromInclusive,
        @ParametricNullness K toKey,
        boolean toInclusive) {
      return asMap(set.subSet(fromKey, fromInclusive, toKey, toInclusive), function);
    }

    @Override
    public NavigableMap<K, V> headMap(@ParametricNullness K toKey, boolean inclusive) {
      return asMap(set.headSet(toKey, inclusive), function);
    }

    @Override

    }

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

    @Override
    ImmutableSortedSet<C> subSetImpl(
        C fromElement, boolean fromInclusive, C toElement, boolean toInclusive) {
      if (!fromInclusive && !toInclusive && Range.compareOrThrow(fromElement, toElement) == 0) {

        return delegate().floor(e);
      }
    }

    @Override
    public NavigableSet<E> headSet(E toElement, boolean inclusive) {
      synchronized (mutex) {
        return Synchronized.navigableSet(delegate().headSet(toElement, inclusive), mutex);
      }
    }

    @Override
    public SortedSet<E> headSet(E toElement) {
      return headSet(toElement, false);
    }

        return delegate().floor(e);
      }
    }

    @Override
    public NavigableSet<E> headSet(E toElement, boolean inclusive) {
      synchronized (mutex) {
        return Synchronized.navigableSet(delegate().headSet(toElement, inclusive), mutex);
      }
    }

    @Override
    public SortedSet<E> headSet(E toElement) {
      return headSet(toElement, false);
    }

   * value} is greater than {@code max}, {@code max} is returned.
   *
   * @param value the {@code char} value to constrain
   * @param min the lower bound (inclusive) of the range to constrain {@code value} to
   * @param max the upper bound (inclusive) of the range to constrain {@code value} to
   * @throws IllegalArgumentException if {@code min > max}
   * @since 21.0
   */

   * value} is greater than {@code max}, {@code max} is returned.
   *
   * @param value the {@code short} value to constrain
   * @param min the lower bound (inclusive) of the range to constrain {@code value} to
   * @param max the upper bound (inclusive) of the range to constrain {@code value} to
   * @throws IllegalArgumentException if {@code min > max}
   * @since 21.0
   */

   * value} is greater than {@code max}, {@code max} is returned.
   *
   * @param value the {@code short} value to constrain
   * @param min the lower bound (inclusive) of the range to constrain {@code value} to
   * @param max the upper bound (inclusive) of the range to constrain {@code value} to
   * @throws IllegalArgumentException if {@code min > max}
   * @since 21.0
   */

   * value} is greater than {@code max}, {@code max} is returned.
   *
   * @param value the {@code char} value to constrain
   * @param min the lower bound (inclusive) of the range to constrain {@code value} to
   * @param max the upper bound (inclusive) of the range to constrain {@code value} to
   * @throws IllegalArgumentException if {@code min > max}
   * @since 21.0
   */

   *
   * <p><b>Java 21+ users:</b> Use {@code Math.clamp} instead.
   *
   * @param value the {@code float} value to constrain
   * @param min the lower bound (inclusive) of the range to constrain {@code value} to
   * @param max the upper bound (inclusive) of the range to constrain {@code value} to
   * @throws IllegalArgumentException if {@code min > max}
   * @since 21.0
   */