code: final boolean tokenIs(String s)
    {
      return (m_token != null) ? (m_token.equals(s)) : (s == null);
    }
docs: Check whether m_token matches the target string.
  
  @param s A string reference or null.
  
  @return If m_token is null, returns false (or true if s is also null), or
  return true if the current token matches the string, else false.