code: protected ParseSetup guessSetup_impl(ByteVec v, byte[] bits, ParseSetup userSetup) {
      ParseSetup ps = guessInitSetup(v, bits, userSetup);
      return guessFinalSetup(v, bits, ps);
    }
docs: Actual implementation of the guessSetup method. Should almost never be overridden (the only
  exception is the GuessParserProvider).
  @param v
  @param bits
  @param userSetup
  @return