[antlr-interest] Re: check tokens for whitespace?

[Joan Pujol]

Hi,

I think that you have to do is use the tokens section of the lexer for
your reserved keywords
(in your case func)

tokens {
    FUNC="func";

}
VAR: ('a'..'z') ('a'..'z'|'0'..'9')*;


Make sure that in VAR you use the testLiterals option to true. This is
the default, but be sure that you haven't put it to false in global
options.

Cheers,

On Fri, 24 Sep 2004 01:29:13 -0000, mazypath <eitan at cs.ucla.edu> wrote:
> 
> Thanks for your quick answer.  My question may not have been clear.
> 
> I would like VAR to be any string including those starting including
> those that start with "plus"  (or another keyword/token) followed by
> letters or integers.  so:
>   helloWorld ---> VAR
>   plus ---> FUNC
>   plus1 ---> VAR
> 
> In your reply VAR must start with "plus".  Add the origional VAR
> defintion ('a'..'z') ('a'..'z'|'0'..'9' | '.')* to the rules below and
> you get nondeterminism.
> 
>   VAR :
>     ("plus " ( 'a'..'z'|'0'..'9')) => ('a'..'z') ('a'..'z'|'0'..'9' |
> '.')* |
>     (('a'..'z') ('a'..'z'|'0'..'9' | '.')*) |
>     ("plus ") => "plus " {$setType(FUNC); } ;
> 
> There is now nondetermenism between block 2 and 3.  Move the last
> block up and "plus1" is labled FUNC again.  Even if this were to work
> I have a lot of keywords, defining them WITHIN another token
> definition seems bad.
> 
> What would be ideal (in my mind) is if I could leave VAR as is and
> change FUNC to be something like
>   FUNC: "plus" ~( 'a'..'z'|'0'..'9')
> And then have that last charater not be consumed (or re-inject it into
> the stream).
> 
> Thank you agian!
> 

-- 
Joan Jesús Pujol Espinar


 
Yahoo! Groups Links

<*> To visit your group on the web, go to:
    http://groups.yahoo.com/group/antlr-interest/

<*> To unsubscribe from this group, send an email to:
    antlr-interest-unsubscribe at yahoogroups.com

<*> Your use of Yahoo! Groups is subject to:
    http://docs.yahoo.com/info/terms/