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Re: RIF Core shortened

From: Christian de Sainte Marie <csma@ilog.fr>
Date: Mon, 17 Nov 2008 18:56:20 +0100
Message-ID: <4921B044.8030402@ilog.fr>
To: Gary Hallmark <gary.hallmark@oracle.com>
CC: kifer@cs.sunysb.edu, Patrick Albert <palbert@ilog.fr>, Dave Reynolds <der@hplb.hpl.hp.com>, "Boley, Harold" <Harold.Boley@nrc-cnrc.gc.ca>, Adrian Paschke <Adrian.Paschke@gmx.de>, Axel Polleres <axel.polleres@deri.org>, RIF WG <public-rif-wg@w3.org>

Gary, all,

Could you back up a little bit for me, please? I am not on the Core mailing list, and I might have missed part of the discussion.

Gary, you say that you need to assert membership and subclass relationships in order to  "map (schema valid) XML documents to frames". I assume that, when you talk about mapping XML document to frames, you refer to your strawman proposal for mapping XML schema valid XML data to RIF frames [1]: is that correct?

If yes, I do not understand why you say that it would require that # and ## by assert, conditionally or inconditionally? Can you (re-)explain that part, please?

On the other hand, I am assuming, also, that when class membership and the class hierarchy are specified in an external XML schema (which is what [1] is about), # and ## are effectively processed as if they were External, that is: they need not be asserted to be true; and they cannot be asserted (not in a core PR system, at least).

Is that the key?

If yes, isn't the solution to allow # and ## as Externals: External are not allowed in the conclusion, but logical (or local) # and ## are.

That would resolve the question, as far as I understand, and since what can be External is at risk in BLD, we need not come back before LC to change it, and thus we can have that in Core (if Core wants it; Core wants only logical # and ##, no pb either: External # and ## are an extension for PRD, and maybe BLD. If Core wants only External # and ##, no pb, again: PRD will be happy with that, and BLD can extend to logical # and ## if needed)...

Or am I beside the point?



[1] http://lists.w3.org/Archives/Public/public-rif-wg/2008Oct/0046.html
Gary Hallmark wrote:

> I think we don't have to distinguish "creation" vs. "modification" for 
> unconditional conclusions (aka facts).  It seems the worst thing that 
> happens is we have to translate
> _o # eg:class1
> _o # eg:class2
> The translator can always look ahead at *all* the facts before deciding 
> what to do.  In this case, the translator searches for a constructor 
> (taking no arguments) that can create an instance of eg:class1 *and* 
> eg:class2.  Because we allow # only in unconditional conclusions, this 
> kind of lookahead is always easy and possible.
> Michael Kifer wrote:
>> On Mon, 17 Nov 2008 15:06:02 +0100
>> "Patrick Albert" <palbert@ilog.fr> wrote:
>>> Right, this task stretches us a little too much... :-/
>>> I am happy to support your proposal "allow # and ## in Core in rule
>>> conditions and *unconditional* rule conclusions" as long as in the
>>> "unconditional conclusions" we limit ourselves to the creation of new
>>> objects, not including the modification of the class of an already
>>> existing object.     
>> The latter (creation vs modification) is not possible to define in the 
>> core.
Received on Monday, 17 November 2008 17:57:48 UTC

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