[m-rev.] lex and moose changed

[Peter Schachte]

> > A sequence or stream type class should solve that.  I'd define a sequence as
> > having an emtpy/1 predicate and a next/3 predicate that returns the next and
> > rest.  A stream would be the same as a sequence, except it would have only
> > unique (destructive) modes.
> 
> You've just hit a snag there: the token predicates I was using depended on
> being able to backtrack to find the longest matching token. A stream type
> class with unique modes would be the same as using read_char now. It would
> be nice to have a stream that used transparent putback on backtracking.

I guess I'd call them sequences rather than streams, then.  Of course, that
could be done.

But I think the better solution is to somehow compile the grammar into a
deterministic tokenizer.


-- 
Peter Schachte                     Even if you are a minority of one, the
mailto:schachte at cs.mu.OZ.AU        truth is the truth.
http://www.cs.mu.oz.au/~schachte/      -- Mahatma Gandhi 
Phone: +61 3 8344 9166             
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