I've not liked the way the conversation over the last couple of days has
been going, so I'm happy to see Alan push back towards the middle. I'm
buried in stuff here and was just too unhappy to reply.
I want the CQL syntax to be a naively simple as possible, even to the point
of losing some functionality. (I hope not to, but you need to understand
where I'm starting from.) I know that the SRW folks will have code between
their users and CQL and I hear the SRU folks saying the same. But, once
this stuff is turned loose, there are going to be folks putting up dumb HTML
forms that poke unmediated queries at our servers and I want them to have a
chance of working. I also know that there will be programmers hand-crafting
URLs to poke at us and I don't want to replace the complexity of z39.50 with
the complexity of CQL. This needs to be a language obvious to idiots.
I suspect that we're going to have to agree on adding an optional query-type
parameter so that we can use the appropriate language for the appropriate
situation. But right now, I want it simple.
CCL was designed to be the language that end-users got taught to search
bibliographic utilities. It is simple and embedded, in one form or another,
in most local library systems. It needs to be our starting place. I've got
no problem with adding complex syntax to do non-core complex stuff. But I'm
going to resist tinkering with the base stuff.
> -----Original Message-----
> From: Alan Kent [mailto:[log in to unmask]]
> Sent: Thursday, May 23, 2002 6:39 PM
> To: [log in to unmask]
> Subject: Re: bath, cql, etc.
> On Thu, May 23, 2002 at 11:36:21AM -0400, Ray Denenberg wrote:
> > Alan Kent wrote:
> > > (title=me and) or (title=mine)
> > >
> > > is a syntax error because "and" is a resrved word.
> > Why does "and" have to be reserved?
> > I like the idea of the parenthesis around operands, which would mean
> > we don't need quotes around the term, we can embed space in
> the term,
> > and we don't need to reserve operator words.
> > Is "and" reserved in ccl and is that why you assert that it's
> > reserved? If that's the reason then why don't we just ignore that
> > rule?
> > --Ray
> (All these little syntax arguments are actually one of the reasons
> I like the idea of starting with CCL and deviating only if its not
> appropriate - it saves time! :-)
> A question back: Who is the target audience of CQL? Most programmers
> are familiar with concepts such as reserved words for AND and OR,
> and parenthesis to change operator precedence. In most programming
> languages, you dont have to put parenthesis around boolean conditions.
> Do I have to type in parenthesis even if there is a single condition?
> *Most* (not all) grammars go for context free interpretation of tokens
> (ie: unquoted 'and' inside or outside parethesis is the same thing).
> It makes it easier to use tools like lex and yacc.
> So I would say, yes there are lots of options, working out base
> guidelines (such as who is the grammar for etc) is important in
> order to avoid spending too much time on syntax.
> I *personally* like:
> * context free tokenization rules
> * using similar rules to things that exist where suitable
> Alan Kent (mailto:[log in to unmask],
> Project: TeraText Technical Director, InQuirion Pty Ltd
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