Re: if/else if

["yuntao" <yuntao@eventmonitor.com>]

Sorry, please ignore the last message. I actually had an unused token "elseif" defined.

Even though grammer does not use it, I guess it causes trouble to the parser.

 

Thanks for the help.

 

Yuntao Cui

 

----- Original Message -----

From: yuntao

To: Etienne M. Gagnon ; sablecc-list@sable.mcgill.ca ; Roger Keays

Cc: yuntao@eventmonitor.com

Sent: Tuesday, October 02, 2001 2:39 PM

Subject: if/else if

Hi,

 

Thanks for the help. Now I changed my grammer like the sample java grammer as follows:

 

     if_statement={if_else} if l_par general_expression r_par [true]:statement_no_if else [false]:statement |
          {if} if l_par general_expression r_par statement;
     if_statement_no_if =
          {if_else} if l_par general_expression r_par [true]:statement_no_if else [false]:statement_no_if;

 

It solves reduce/shift problem. Now I can build the parser. Everything works fine for my code except

that I can not put "else if" together. For example, all the followings are fine:

 

1) "if (a>5) {b=5;}"

2) "if (a>5) {b=5;} else {c=5;}"

3) "if (a>5) {b=5;} else {if(a>4) {;}}"

 

But if I put "else if" together, like

 

"if (a>5) {b=5;} else if (a>4) {b=3;}", then I got the following error message:

 

"parser.ParserException: [1,17] expecting: EOF", the position is pointing to the beginning of

the "else". Please let me what is your thought.

 

Thanks a lot.

 

Yuntao Cui