Re: definition of domain

Jeen Broekstra wrote:

> On Thu, 12 Oct 2000, Tom Van Eetvelde wrote:
>
> > I clearly phrased my thoughts the wrong way. See answer to
> > Pierre-Antoine. With applying the property to a subclass, I
> > really mean the sublcass (node in a drawing) itself and not the
> > subclass'es instances.
>
> Ah, yes, I saw that after I had already sent my reply.
>
>     <rdfs:Class rdf:ID="carnivore">
>          <rdfs:subClassOf rdf:resource = "#animal"/>
>          <eats rdf:resource="#animal"/>
>     </rdfs:Class>
>
> Actually I think it is an interesting idea. What you propose is
> what is being done in OIL right now with slotconstraints:
>
>     <rdfs:Class ID="carnivore">
>         <rdfs:subClassOf rdf:resource="#animal"/>
>         <oil:hasSlotConstraint>
>             <oil:ValueType>
>                 <oil:hasProperty rdf:resource="#eats"/>
>                 <oil:hasClass rdf:resource="#animal"/>
>             </oil:ValueType>
>         </oil:hasSlotConstraint>
>     </rdfs:Class>
>
> The OIL way is more explicit, and allows other types of local
> restrictions besides range restrictions. However, your way is
> simpler and more intuitive.

Hello Jeen,

The OIL article was the source for this idea. Indeed, the OIL way is very explicit, but not so
intuitive. I was experimenting with RDF drawings picturing how I would capture that a carnivore eats
meat. I couldn't help drawing an arc from carnivore, knowing it was wrong from spec point of view.
Then the ball got rolling...

Anyway, an interesting application of my proposed construct is defaulting values. CC/PP is having
difficulties modelling defaults in a natural way in my opinion. It would be nice if a user can type
in 'Alcatel WAP GSM' and let the system look up what default values go with this type of GSM. For
the other 'not yet filled in properties', the user can be asked for additional input. 'Alcatel WAP
GSM' as class still covers a whole range of models with colours and size, ...

Regards,

Tom.