- From: Holger Knublauch <holger@topquadrant.com>
- Date: Wed, 06 Dec 2006 16:48:30 -0800
- To: public-owl-dev@w3.org
Jeff Z. Pan wrote: > Hi Holger, >> >> I am wondering why user-defined datatypes are not modeled as instances >> of the RDF Schema class rdfs:Datatype (similar to the hack suggested >> in the Protege 3 implementation [1]). Without knowing the design >> decisions that lead to the use of owl:DataRange, my naive point of >> view would be that rdfs:Datatypes may make it more consistent with the >> semantic web stack. I am sure the working group had good reasons for >> selecting owl:DataRange, but it would be useful to understand them >> from the outside. >> > In RDF, a datatype (instance of rdfs:Datatype) and a class (instance of > rdfs:Class) can share instances, such as the integer 42. While in OWL DL > (and hence OWL 1.1), the datatype domain is disjoint with the object > domain; therefore, sharing instances is not possible for an OWL DL/1.1 > datatype and an OWL DL/1.1 class. > > Greetings, > Jeff Thanks, Jeff. But in RDF Schema, the pre-defined system datatypes such as xsd:int are instances of rdfs:Datatype as well [1]. Are user-defined datatypes different from system datatypes, or is OWL 1.1 changing the RDF Schema semantics here? Apologies if this has been discussed and written down elsewhere - any pointers are appreciated. Regards, Holger [1] http://www.w3.org/TR/rdf-schema/#ch_datatype
Received on Thursday, 7 December 2006 00:52:43 UTC