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Re: Two issues with RIF-Core

From: Sandro Hawke <sandro@w3.org>
Date: Fri, 08 May 2009 10:16:40 -0400
To: Dave Reynolds <der@hplb.hpl.hp.com>
cc: Gary Hallmark <gary.hallmark@gmail.com>, RIF WG <public-rif-wg@w3.org>
Message-ID: <18045.1241792200@ubehebe>

> > 2. PRD and Core allow frame properties to be TERMs, i.e. Frame ::=
> > TERM '[' (TERM '->' TERM)* ']'
> > 
> > This is likely to be a problem for most production rule engines. It
> > would be much easier if Frame ::= TERM '[' (Const'->' TERM)* ']'
> 
> Agreed.

I'm not sure this is a good idea.

Partly for the sake of argument, let me suggest an alternative.  Take
frames out of Core and PRD.  If we restrict frames as you're proposing,
then (as far as I can tell) they don't actually provide any
functionality.  Wherever you were using s[p->o], just use p(s,o).  Why
have two parallel features that provide exactly the same functionality?
As I understood it, the whole point of frames was to allow for
quantifying over predicates.

Dave, with this change, how would you implement RDFS (etc) rules?

     -- Sandro
Received on Friday, 8 May 2009 14:16:50 GMT

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