W3C home > Mailing lists > Public > www-rdf-interest@w3.org > October 2000

Re: definition of domain

From: Pierre-Antoine CHAMPIN <champin@bat710.univ-lyon1.fr>
Date: Thu, 12 Oct 2000 11:23:28 +0200
Message-ID: <39E58310.CEAA2493@bat710.univ-lyon1.fr>
To: Tom Van Eetvelde <tom.van_eetvelde@alcatel.be>
CC: www-rdf-interest@w3.org
Tom Van Eetvelde wrote:
> What I find a bit unfortunate is the fact that a defined property may only be used on instances of the class mentioned in the domain. I believe the property should also be applicable for subclasses of the class in the domain.

       2.3.2. rdfs:subClassOf

       This property specifies a subset/superset relation between classes. The
       rdfs:subClassOf property is transitive. If class A is a subclass of some
       broader class B, and B is a subclass of C, then A is also implicitly a
       subclass of C. Consequently, resources that are instances of class A will
       also be instances of C, since A is a sub-set of both B and C. Only instances
       of rdfs:Class can have the rdfs:subClassOf property and the property value
       is always of rdf:type rdfs:Class. A class may be a subclass of more than one
       class. 

Instances of a subclass of C are also instances of the class C,
so using a property with domain C with instances of subclasses is allowed.

  Pierre-Antoine

-- 
Sometimes I think the surest sign that intelligent life exists elsewhere in the
universe is that none of it has tried to contact us.
(Bill Watterson -- Calvin & Hobbes)
Received on Thursday, 12 October 2000 05:24:42 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Monday, 7 December 2009 10:51:44 GMT