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Re: [Core] updated safeness condition

From: Dave Reynolds <der@hplb.hpl.hp.com>
Date: Fri, 06 Feb 2009 11:42:42 +0000
Message-ID: <498C2232.8010005@hplb.hpl.hp.com>
To: Jos de Bruijn <debruijn@inf.unibz.it>
CC: RIF WG <public-rif-wg@w3.org>

Jos de Bruijn wrote:
> I found that the definition is overly restrictive in the face of
> disjunction; it required all variables to be safe in every disjunct,
> even if the variable does not occur in the head. This is, however, a
> situation we do want to allow.
> I updated the definition yet again.
> This disjunction in core is giving me a headache.
> Would the difficulties of Jos with the definition of safeness be
> sufficient grounds for getting rid of disjunction in core?  ;-)

Works for me :-)

Given that disjunction (and several other things like nested functions) 
are just syntactic sugar. One option might be to define the 
transformation to a stripped down Core without the sugar and define 
safeness in terms of that.

Received on Friday, 6 February 2009 11:44:04 UTC

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