private RsToken identifier(int value) throws RsParsingException{
      StringBuffer sbuff;
      sbuff=token.getStringBuffer();
      sbuff.append((char)value);
      value=nextChar();
      while(value=='_'
         || value>='A' && value<='Z'
         || value>='a' && value<='z'
         || value>='0' && value<='9'){
         sbuff.append((char)value);
         value=nextChar();
      }
      pushBackChar(value);
      token.setType(RsToken.TT_IDENTIFIER);
      return token;
   }