.matches(
            Pattern.compile(
                Doubles.FLOATING_POINT_PATTERN.pattern(), Doubles.FLOATING_POINT_PATTERN.flags()));
  }

  @GwtIncompatible // Doubles.tryParse
  public void testTryParseHex() {
    for (String signChar : ImmutableList.of("", "+", "-")) {
      for (String hexPrefix : ImmutableList.of("0x", "0X")) {
        for (String iPart : ImmutableList.of("", "0", "1", "F", "f", "c4", "CE")) {