- From: Marc Carrion <marc_carrion@yahoo.es>
- Date: Thu, 23 Jan 2003 07:26:41 -0800 (PST)
- To: www-rdf-interest@w3.org
I hope this is the place :) Regards, Marc --- "Ralph R. Swick" <swick@w3.org> wrote: > Date: Wed, 22 Jan 2003 14:13:18 -0500 > To: marc@jfcarrion.com > From: "Ralph R. Swick" <swick@w3.org> > Subject: Re: [Moderator Action] abstract class > > Marc, your message (attached) was set aside for > manual attention because the RDF Core WG mailing > list only accepts posts from list subscribers. > > I suggest you repost your comment to the public > comments mailing list mailto:www-rdf-comments@w3.org > as cited in the Status section of the > RDF Schema Working Draft > http://www.w3.org/TR/rdf-schema/ > > -Ralph Swick > W3C/MIT > > At 09:17 AM 1/22/2003 -0500, Marc Carrion wrote: > > > > After some time ago the w3c decided to change the > >semantics of multiple 'rdfs:range' and > 'rdfs:domain', > >lots of people with different ideas have discussed > its > >merits extensively. And although the new semantics > >seems to work better, it has lost some of its > >descriptive power, namely: > > > > > > To express that the 'rdfs:domain' of a property > is > >A or B, we should create the class C and define A > and > >B as 'rdfs:subClassOf' of C; since class C remains > >instantiable, we would like to define C as > abstract. > > At first we thought we could achieve it by > taking > >advantage of the difference between 'Resource' and > >'Class'; the 'rdfs:range' of the property > 'rdf:type' > >is 'rdfs:Class', so C could be defined as > ><rdf:Resource rdf:ID="C"/>. Everything would be OK > but > >for the fact that > > the 'rdfs:range' of the property > 'rdfs:subClassOf' > >is 'rdfs:Class' as well, hence A and B cannot be > >subclasses of C. We considered then changing it to > >'Resource', but then any resource of any type in > our > >instance would be valid as range of the property > >'rdfs:subClassOf'. > > That's why we would like to propose adding a > >'Resource' in the RDFS called 'rdfs:AbstractClass', > >whose 'rdf:type' would be 'rdfs:Class'; > 'rdfs:Class' > >would be then its 'rdfs:subClassOf', and the > >'rdfs:range' and 'rdfs:domain' of the property > >'rdfs:subclassof' would be this new > >'rdfs:AbstractClass'. > > > > Regards, > > Marc > > > > PS: Just a thought. 'rdfs:seeAlso' > 'rdfs:domain' > >is 'rdf:Resource', the last resource defined in the > >new schema > > <rdf:Description > >rdf:about="http://www.w3.org/2000/01/rdf-schema#"> > > <rdfs:seeAlso > >rdf:resource=http://www.w3.org/2000/01/rdf-schema-more#"/> > > </rdf:Description> > > http://www.w3.org/2000/01/rdf-schema# is > not > >a 'rdf:Resource', so, it can not be the domain, and > >the same applies for > >http://www.w3.org/2000/01/rdf-schema-more# (it > cannot > >be the range) > > > >===== > ===== ......\|||/................................................ (. .) -oOOo---0---oOOo------- |marc_carrion@yahoo.es| | ooO Ooo | ----( )--( )----------- () () __________________________________________________ Do you Yahoo!? Yahoo! Mail Plus - Powerful. Affordable. Sign up now. http://mailplus.yahoo.com
Received on Thursday, 23 January 2003 10:29:07 UTC