* input element is mapped to a key and a stream of values, each of which are put into the
   * resulting {@code Multimap}, in the encounter order of the stream and the encounter order of the
   * streams of values.
   *
   * <p>Example:
   *
   * {@snippet :
   * static final ImmutableListMultimap<Character, Character> FIRST_LETTER_MULTIMAP =

   * over keys in the order they were first encountered in the input, and the values for each key
   * are iterated in the order they were encountered. If two values for the same key are {@linkplain
   * Object#equals equal}, the first value encountered is used.
   *
   * @throws NullPointerException if any key, value, or entry is null
   * @since 19.0
   */

   * input element is mapped to a key and a stream of values, each of which are put into the
   * resulting {@code Multimap}, in the encounter order of the stream and the encounter order of the
   * streams of values.
   *
   * <p>Example:
   *
   * {@snippet :
   * static final ImmutableListMultimap<Character, Character> FIRST_LETTER_MULTIMAP =

/// tip

  /**
   * Returns a {@code Collector} that accumulates the input elements into a new {@code
   * ImmutableSet}. Elements appear in the resulting set in the encounter order of the stream; if
   * the stream contains duplicates (according to {@link Object#equals(Object)}), only the first
   * duplicate in encounter order will appear in the result.
   *
   * @since 33.2.0 (available since 21.0 in guava-jre)
   */

   * over keys in the order they were first encountered in the input, and the values for each key
   * are iterated in the order they were encountered. If two values for the same key are {@linkplain
   * Object#equals equal}, the first value encountered is used.
   *
   * @throws NullPointerException if any key, value, or entry is null
   * @since 19.0
   */

   * specified supplier, whose cells are generated by applying the provided mapping functions to the
   * input elements. Cells are inserted into the generated {@code Table} in encounter order.
   *
   * <p>If multiple input elements map to the same row and column, an {@code IllegalStateException}
   * is thrown when the collection operation is performed.
   *

   * specified supplier, whose cells are generated by applying the provided mapping functions to the
   * input elements. Cells are inserted into the generated {@code Table} in encounter order.
   *
   * <p>If multiple input elements map to the same row and column, an {@code IllegalStateException}
   * is thrown when the collection operation is performed.
   *

  /**
   * Returns a {@code Collector} that accumulates the input elements into a new {@code
   * ImmutableSet}. Elements appear in the resulting set in the encounter order of the stream; if
   * the stream contains duplicates (according to {@link Object#equals(Object)}), only the first
   * duplicate in encounter order will appear in the result.
   *
   * @since 21.0
   */
  public static <E> Collector<E, ?, ImmutableSet<E>> toImmutableSet() {

   * and values are the result of applying the provided mapping functions to the input elements.
   * Entries appear in the result {@code ImmutableMap} in encounter order.
   *
   * <p>If the mapped keys contain duplicates (according to {@link Object#equals(Object)}, an {@code
   * IllegalArgumentException} is thrown when the collection operation is performed. (This differs