}

    /**
     * Adds {@code element} to the {@code ImmutableSortedMultiset}.
     *
     * @param element the element to add
     * @return this {@code Builder} object
     * @throws NullPointerException if {@code element} is null
     */
    @CanIgnoreReturnValue
    @Override
    public Builder<E> add(E element) {
      super.add(element);
      return this;
    }

    /**

    assertEquals("Should be able to peek() at first element", "A", peekingIterator.peek());
    assertEquals(
        "Should be able to peek() first element multiple times", "A", peekingIterator.peek());
    assertEquals(
        "next() should still return first element after peeking", "A", peekingIterator.next());

    assertEquals("Should be able to peek() at middle element", "B", peekingIterator.peek());
    assertEquals(

    Iterator<E> iterator = collection.iterator();
    Object element = iterator.next();
    // If it's an Entry, it may become invalid once it's removed from the Map. Copy it.
    if (element instanceof Entry) {
      Entry<?, ?> entry = (Entry<?, ?>) element;
      element = mapEntry(entry.getKey(), entry.getValue());
    }
    assertTrue(collection.contains(element)); // sanity check
    iterator.remove();

    IllegalArgumentException expected =
        assertThrows(IllegalArgumentException.class, () -> getOnlyElement(iterator));
    assertThat(expected).hasMessageThat().isEqualTo("expected one element but was: <one, two>");
  }

  public void testGetOnlyElement_noDefault_fiveElements() {
    Iterator<String> iterator = asList("one", "two", "three", "four", "five").iterator();
    IllegalArgumentException expected =

    /**
     * Return the index of the next lower element in the list, or {@code -1} if there is no such
     * element.
     */
    NEXT_LOWER {
      @Override
      int resultIndex(int higherIndex) {
        return higherIndex - 1;
      }
    },
    /**
     * Return the index of the next higher element in the list, or {@code list.size()} if there is
     * no such element.
     */
    NEXT_HIGHER {

   * stream.filter(element::equals).count()}. If {@code element} might be null, use {@code
   * stream.filter(Predicate.isEqual(element)).count()} instead.
   *
   * @see java.util.Collections#frequency(Collection, Object) Collections.frequency(Collection,
   *     Object)
   */
  public static int frequency(Iterable<?> iterable, @Nullable Object element) {
    if ((iterable instanceof Multiset)) {

   * Returns an {@link Optional} containing the first element in this fluent iterable. If the
   * iterable is empty, {@code Optional.absent()} is returned.
   *
   * <p><b>{@code Stream} equivalent:</b> if the goal is to obtain any element, {@link
   * Stream#findAny}; if it must specifically be the <i>first</i> element, {@code Stream#findFirst}.
   *
   * @throws NullPointerException if the first element is null; if this is a possibility, use {@code

   * Returns an {@link Optional} containing the first element in this fluent iterable. If the
   * iterable is empty, {@code Optional.absent()} is returned.
   *
   * <p><b>{@code Stream} equivalent:</b> if the goal is to obtain any element, {@link
   * Stream#findAny}; if it must specifically be the <i>first</i> element, {@code Stream#findFirst}.
   *
   * @throws NullPointerException if the first element is null; if this is a possibility, use {@code

}\n\n  return parseSelector(selector)\n}\n\nconst SelectorEngine = {\n  find(selector, element = document.documentElement) {\n    return [].concat(...Element.prototype.querySelectorAll.call(element, selector))\n  },\n\n  findOne(selector, element = document.documentElement) {\n    return Element.prototype.querySelector.call(element, selector)\n  },\n\n  children(element, selector) {\n    return [].concat(...element.children).filter(child => child.matches(selector))\n  },\n\n  parents(element, selector)...

    }

    /**
     * Adds {@code element} to the {@code ImmutableSortedSet}. If the {@code ImmutableSortedSet}
     * already contains {@code element}, then {@code add} has no effect. (only the previously added
     * element is retained).
     *
     * @param element the element to add
     * @return this {@code Builder} object
     * @throws NullPointerException if {@code element} is null
     */
    @CanIgnoreReturnValue