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RE: F2F12: Core safety criterion

From: Boley, Harold <Harold.Boley@nrc-cnrc.gc.ca>
Date: Mon, 12 Jan 2009 10:50:07 -0500
Message-ID: <E4D07AB09F5F044299333C8D0FEB45E904FFE81B@nrccenexb1.nrc.ca>
To: "Dave Reynolds" <der@hplb.hpl.hp.com>, "RIF WG" <public-rif-wg@w3.org>

> Could I ask that we try to 
> make time to cover this issue during that session?

I learned that Axel is of the same opinion
(and he is in almost the same time zone).
I'm strongly supporting this as well.

Christian, could you still -- before you leave to Portland -- edit
http://www.w3.org/2005/rules/wiki/F2F12

Also, on Day 2,

17:00-18:00 - ...

at the latest, we might want to discuss about the
future "reduced workload WG":
http://lists.w3.org/Archives/Public/public-rif-wg/2008Dec/0103.html

Please let us know when you are done so we can all print
the revised agenda and (brief?) reading list before we leave.

Is there a restaurant (in one of the hotels?) near Oracle
where we can all meet up tomorrow night?

Harold


-----Original Message-----
From: public-rif-wg-request@w3.org [mailto:public-rif-wg-request@w3.org]
On Behalf Of Dave Reynolds
Sent: January 12, 2009 7:28 AM
To: RIF WG
Subject: F2F12: Core safety criterion


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 15:50:51 GMT

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