* syntax</a>.
   *
   * @return a new, empty {@code TreeSet}
   */
  @SuppressWarnings({
    "rawtypes", // https://github.com/google/guava/issues/989
    "NonApiType", // acts as a direct substitute for a constructor call
  })
  public static <E extends Comparable> TreeSet<E> newTreeSet() {
    return new TreeSet<>();
  }

  /**