*
   * <p>The {@link SortedMap#headMap} documentation states that a submap of a submap throws an
   * {@link IllegalArgumentException} if passed a {@code toKey} greater than an earlier {@code
   * toKey}. However, this method doesn't throw an exception in that situation, but instead keeps
   * the original {@code toKey}.
   */
  @Override
  public ImmutableSortedMap<K, V> headMap(K toKey) {
    return headMap(toKey, false);
  }

   *
   * <p>The {@link SortedMap#headMap} documentation states that a submap of a submap throws an
   * {@link IllegalArgumentException} if passed a {@code toKey} greater than an earlier {@code
   * toKey}. However, this method doesn't throw an exception in that situation, but instead keeps
   * the original {@code toKey}.
   */
  @Override
  public ImmutableSortedMap<K, V> headMap(K toKey) {
    return headMap(toKey, false);
  }

        return tmp;
      }
    }
    return null;
  }

  public ImmutableSortedMap<K, V> headMap(K toKey) {
    checkNotNull(toKey);
    return newView(sortedDelegate.headMap(toKey));
  }

  ImmutableSortedMap<K, V> headMap(K toKey, boolean inclusive) {
    checkNotNull(toKey);
    if (inclusive) {
      K tmp = higher(toKey);
      if (tmp == null) {