[antlr-interest] Keyword match

[Alexey Demakov]

If you have no identifier rule in lexer, you should define all keywords in lexer rules:

BASE : "base" ;

Otherwise keywords should be in tokens section:

tokens
{
  BASE = "base";
}

And use tokens instead of strings in parser:

ss_base :
     BASE l_name=localName
     {
         // do something with l_name
     }
     ;

I beleive that strings in parser rules are processed correctly only when
they are belong to some lexer rule where literals are tested.

Regards,
Alexey

-----
Alexey Demakov
TreeDL: Tree Description Language: http://treedl.sourceforge.net
RedVerst Group: http://www.unitesk.com

----- Original Message ----- 
From: "Ersin Er" <ersin_er at yahoo.com>
To: <antlr-interest at antlr.org>
Sent: Wednesday, August 24, 2005 3:48 PM
Subject: Re: [antlr-interest] Keyword match


> Hi,
> 
> I have more information about the problem now:
> 
> If I do not have an identifier rule and if I have keywords in the
> grammar then the problem I explained in my previous mail (below) occurs
> (and this is normal I think). If I have include the indentifier rule in
> the lexer and if I do the testLiterals stuff and when I try to test the
> parser it just HANGS without any messages.
> 
> Now, is there any suggestions?
> 
> -- Ersin
> 
> --- Ersin Er <ersin_er at yahoo.com> wrote:
> 
> > Hi all,
> > 
> > I have problem with keyword in my language. Here is a simple
> > production
> > (some action code ommited for briefness):
> > 
> > ss_base :
> >     "base" l_name=localName
> >     {
> >         // do something with l_name
> >     }
> >     ;
> > 
> > What ANTLR says about this grammar is:
> > 
> > "unexpected char 'b'"
> > 
> > The 'b' here is the 'b' of the "base". I face the same problem with
> > all
> > my keywords. ANTLR allways complain about the first character of any
> > keyword in the parser productions. I did the testLiterals trick but
> > it
> > did not help and in fact I do not have an identifier type)
> > 
> > Can you help please?
> > 
> > Greetings.
> > 
> > -- Ersin
> > 
> > 
> > 
> > __________________________________ 
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> 
> 
> --
> Ersin ER
> Arastirma Gorevlisi
> Hacettepe Universitesi
> Bilgisayar Muhendisligi Bolumu
> 
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