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F2F12: Core safety criterion

From: Dave Reynolds <der@hplb.hpl.hp.com>
Date: Mon, 12 Jan 2009 11:28:07 +0000
Message-ID: <496B2947.6090705@hplb.hpl.hp.com>
To: RIF WG <public-rif-wg@w3.org>

One of the outstanding issues that we didn't manage to resolve in time 
for the last publication of Core was the safety criteria.

Amongst the Core editors, at least, there is not yet consensus on 
whether the safety criteria should be strong guarantees of finiteness or 
simply sufficient to make a forward chaining inference strategy viable.

A test case is whether the following Core rule set is safe.

        ex:A(0)
        ex:A(?x) :- ex:A(?y), ?x = ?y + 1, ?x < 10

Clearly we can't solve the halting problem, any safety criteria which 
guarantees finiteness will be over conservative for some usages.

I can't see a separate explicit issue on this but it is implicitly 
included in the second bullet point of Issue-82.

I'd like to see this topic included in the F2F12 agenda. I see we have 
two possibly relevant sessions on the morning of the second day and I'm 
hoping to be able to dial in for both of those. Since the first covers 
Issue-82 that might be the most relevant. Could I ask that we try to 
make time to cover this issue during that session?

Thanks,
Dave
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Received on Monday, 12 January 2009 11:29:22 GMT

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