*
   * @since 19.0 (since 1.0 as constant {@code NONE})
   */
  public static CharMatcher none() {
    return None.INSTANCE;
  }

  /**
   * Determines whether a character is whitespace according to the latest Unicode standard, as
   * illustrated <a
   * href="http://unicode.org/cldr/utility/list-unicodeset.jsp?a=%5Cp%7Bwhitespace%7D">here</a>.
   * This is not the same definition used by other Java APIs. (See a <a