From: bobduff@shell01.TheWorld.com   
      
   > Should I embed filtering rules into the grammar -- perform filtering as I   
   > build the parse tree?   
   >   
   > Or, should I build the parse tree and then have an application perform   
   > filtering on the parse tree?   
      
   I think the second approach is usually simpler.  Separation of concerns.   
   A parser is working with text (or a sequence of tokens, or whatever).   
   A syntax tree is an easier data structure to work with for doing   
   various transformations.   
      
   - Bob   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)