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RE: oneOfDistinct, a proposal for 5.18

From: Peter Crowther <Peter.Crowther@networkinference.com>
Date: Fri, 20 Dec 2002 15:56:45 -0000
Message-ID: <3BE4D3F0FB726240966DEF40418472B5012C8B@NI-LON-SERVER1.ad.networkinference.com>
To: "Dan Connolly" <connolly@w3.org>, "Peter F. \"Patel-Schneider" <pfps@research.bell-labs.com>
Cc: <www-webont-wg@w3.org>

> From: Dan Connolly [mailto:connolly@w3.org] 
> > There is an alternative, however, which I think is 
> preferable in some ways.
> > 
> > OWL could have something like
> > 
> > <owl:AllDistinct rdf:parseType="Collection">
> >   <owl:Person rdf:about="#John"/>
> >   <owl:Person rdf:about="#Susan"/>
> > </owl:AllDisjoint>
> 
> Yes, that's the first design that came to my mind back on 12Nov.
> 
> The downside of it is that it's not straightforward to use
> in the scenario in the guide. You can't just change
> oneOf to oneOfDistinct in...
> 
> <owl:Class rdf:ID="WineColor">
>    <rdfs:subClassOf rdf:resource="#WineDescriptor"/>
>    <owl:oneOf rdf:parseType="Collection">
>      <owl:Thing rdf:about="#White"/>
>      <owl:Thing rdf:about="#Rose"/>
>      <owl:Thing rdf:about="#Red"/>
>    </owl:oneOfDistinct>
> </owl:Class>
> 
> rather, you have to write all that plus
> 
> <owl:AllDistinct rdf:parseType="Collection">
>      <owl:Thing rdf:about="#White"/>
>      <owl:Thing rdf:about="#Rose"/>
>      <owl:Thing rdf:about="#Red"/>
> </owl:AllDistinct>
> 
> I suppose that's a small price to pay versus unravelling the
> semantics document. But I just want us to make an informed
> decision if/when we re-open this.

Dan, I agree that it's more to type, but I think there are three useful
upsides:

1) It's possible to have a oneOf where some of the elements are known to
be distinct and some aren't (because you don't state it at that point);

2) It separates out the assertion that these instances are distinct, so
that a human only has to look at the assertions to find this out, rather
than looking everywhere the instances might be used;

3) It's possibly easier for tool developers - certainly I'd rather
separate out the notion of distinctness from the notion of what is in
any particular description in an OWL authoring tool.  Maybe I'm just
biased from my OilEd use :-).  I suspect it would be easier to roundtrip
in such a tool with the assertion separate from the description as well.
I guess this is restating (2) but for tools.

		- Peter
Received on Friday, 20 December 2002 10:57:18 GMT

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