> >>I can live with that. Especially, since
> >> >p1 b and/a>p2 c
> >>would be ambiguous - and hard to read. To achive this with Alan's
> >>grammar you would have to use
> >> >p1 and/a (>p2 c)
> >Can parsers have a rule (not in the BNF) that makes /a>b always a single
> >modifier, rather than a modifier and a prefix?
> >Making /a >b=c a parse error, but it would be in the BNF anyway as it's
> >not ()ed, so you're not losing anything?
> Don't know what you mean? What BNF? Alan's? Mine?
Alan's.
> The YACC grammar allows both, but is ambiguous - still works in an
> implementation since YACC chooses the right thing - when a conflict arises.
> I propose we choose Alans unambiguous BNF as the spec.
So the answer is yes, we can implement it slightly differently from the
unambiguous but obviously more restrictive grammar without causing any
problems (so long as the parser knows what to do somehow)
Rob
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