private RsToken quotedString() throws RsParsingException {
      int value;
      StringBuffer sbuff;

      sbuff=token.getStringBuffer();
      while(true){
         value=nextChar();
         // check for special characters
         if(value=='\"'){
            token.setType(RsToken.TT_STRING);
            return token;
         }else if(value=='\\'){
            value=nextChar();
            if(value=='n')
               value='\n';
            else if(value=='t')
               value='\t';
         }else if(value=='\n'){
            throw gripe("End-of-line within quoted string on line ");
         }
         sbuff.append((char)value);
      }
   }