From: Jim Freeze <jim@...>
Date: 2003-12-12T04:08:43+09:00
Subject: Re: problems with racc: $end token

On Friday, 12 December 2003 at  3:55:31 +0900, Luke A. Kanies wrote:
> On Fri, 12 Dec 2003, Jim Freeze wrote:
> 
> > Well, in the sample code I see:
> >
> >     @q.push [false, '$']   # optional from 1.3.7
> 
> Yep, I've tried that, along with about nine other variations of having an
> end token.
> 
> > I have successfully left that out of my parsers.
> > Essentially, the samples just tokenize the file
> > (and store the tokens in @q) then call do_parse.
> >
> > do_parse apparently gets tokens from the stack by
> > calling next_token, which returns to tokens one
> > at a time by calling @q.shift. This would suggest
> > that when you are done all you need to do is return
> > the same value as [].shift #=> nil.
> 
> Yeah, all the code does it that way, but there shouldn't be a functional
> difference between collecting the tokens in parse() and returning them in
> next_token(), and just collecting and returning them in next_token().
> Either way, I've switched to a method like the examples, and I've
> corrected my regex problems, and I still get an error.
> 

I agree. Could be a grammar/file syntax mismatch.

> At this point I think it's a problem with my grammar, that I'm somehow not
> correctly specifying the end of the parsing.  Obviously, though, I don't
> know how to say "hey, the file is over, stop looking" or whatever the
> magic words are.  I _know_ that the false token is supposed to do that,
> but for some reason racc thinks it shouldn't be expecting that token yet.
> 
> In case anyone feels like pointing out my idiocy, here's my grammar as it
> stands now:
 
Ok, I'll take a look. At your grammar that is, not your idiocy. :)

-- 
Jim Freeze
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This is the ____LAST time I take travel suggestions from Ray Bradbury!