anchor.diff:    |  SEMICOLON
     ;
   
  +quiet_row_separator_list :
  +     row_separator (quiet_element_separator_list row_separator)*
  +  |  
  +  ;
  +
   element_list :
        element (element_separator_list element)*
     ;
  
positive.code:      {isElementSeparator()}?
          ( {isPrevTokenElementSeparator()}? FILLER            //just echo
          | FILLER {System.err.println("inserting comma before " + input.LT(1));}-> template(filler={$text}) ",<filler>")    //insert comma
    ;
  
  input_params :
  
negative.code:   ;
  
  element_separator_comma :
       {isPrevTokenElementSeparator()}? COMMA {System.err.println("deleting comma " + retval.start);}-> template() "" //delete comma
    |  COMMA                                                   //just echo
    ;
  
  