On 26/6/09 18:22, Tim rdf wrote:
[1] http://www.ifs.univie.ac.at/schandl/2009/06/domain+range_bad.png
is indicating that
foaf:holdsAccount rdfs:domain foaf:Agent; rdfs:range foaf:OnlineAccount .
Is constraining a property with BOTH a domain and range a good design
pattern? It seems rather short-sighted with respect to reuse and extension.
It depends a lot on what you're trying to express.
In this FOAF case, the classes at either end still have some vagueness.
We say only that an Agent is something that does something. And
regarding OnlineAccount (which is superclass of sioc:User in SIOC) there
are some different styles for identifying them with URIs: some use URIs
of the pages associated with those accounts.
Given that the classes linked here are already pretty broad and
"settling down" into a deployment practice, the domain/range constraints
still leave some flexibility and room for practice to evolve.
Dan
