Date:         Mon, 1 Dec 2003 10:54:35 +0000
Reply-To:     "Z39.50 Next-Generation Initiative" <[log in to unmask]>
Sender:       "Z39.50 Next-Generation Initiative" <[log in to unmask]>
From:         Robert Sanderson <[log in to unmask]>
Subject:      Re: New proposed grammar for CQL (revised from Yacc grammar)
Comments: To: "Z39.50 Next-Generation Initiative" <[log in to unmask]>
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In-Reply-To:  <[log in to unmask]>
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> If it's the last grammar you put up, it is unabiguous which is good.
> And, yes, it doesn't allow
>  >p1 b and >p2 c
> 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?

Rob

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