- From: Patrick Stickler <patrick.stickler@nokia.com>
- Date: Fri, 15 Feb 2002 19:23:00 +0200
- To: RDF Core <w3c-rdfcore-wg@w3.org>
Hey folks, Here's an excercise for those of us who think we fully grok the convergence datatyping proposal ;-) I would like to use the following use cases to clarify exactly what is meant by the various *range constraint properties used by the convergence datatyping proposal. I hope this will ensure that we all actually do understand the convergence proposal the same way ;-) Some of these may be "impossible" or "badly formed" cases, or trivial variants of others, and if so, I'd like it to be stated why. I've used rdf:lform rather than rdf:value, to avoid any influence from existing presumptions about what rdf:value means. rdf:lform can be taken to have a range of "lexical form" (member of lexical space) and a domain of "data value" (member of value space) for some datatype. Each example should be considered in isolation, the bnodes are not shared between examples and the only other information that can be applied is that provided by the MT, closure rules, etc. Specific questions: a) what is the range constraint -- value space, lexical space, both? b) what does each bNode, if any, denote? c) is there enough information to recognize datatypes? d) is there enough information to execute a datatyping mapping to a value? I won't give my own answers just yet ;-) 1. dc:date rdfs:range xsd:date . xxx dc:date "2002-02-14" . 2. dc:date rdfs:drange xsd:date . xxx dc:date "2002-02-14" . 3. dc:date rdfs:range xsd:date . xxx dc:date _:1 . _:1 rdf:lform "2002-02-14" . 4. dc:date rdfs:drange xsd:date . xxx dc:date _:1 . _:1 rdf:lform "2002-02-14" . 5. dc:date rdfs:range xsd:date . xxx dc:date _:1 . _:1 rdf:lform "2002-02-14" . _:1 rdf:dtype xsd:date . 6. dc:date rdfs:drange xsd:date . xxx dc:date _:1 . _:1 rdf:lform "2002-02-14" . _:1 rdf:dtype xsd:date . 7. dc:date rdfs:range xsd:date . xxx dc:date _:1 . _:1 xsd:date "2002-02-14" . (note no other statements about xsd:date) 8. dc:date rdfs:drange xsd:date . xxx dc:date _:1 . _:1 xsd:date "2002-02-14" . (note no other statements about xsd:date) 9. dc:date rdfs:range xsd:date . xxx dc:date _:1 . _:1 xsd:date "2002-02-14" . xsd:date rdf:type rdfs:Datatype . xsd:date rdfs:subPropertyOf rdf:lform . 10. dc:date rdfs:drange xsd:date . xxx dc:date _:1 . _:1 xsd:date "2002-02-14" . xsd:date rdf:type rdfs:Datatype . xsd:date rdfs:subPropertyOf rdf:lform . 11. xsd:date rdf:type rdfs:Datatype . xsd:date rdfs:subPropertyOf rdf:lform . xsd:date rdfs:range _:1 . dc:date rdfs:range _:1 . xxx dc:date "2002-02-14" . 12. xsd:date rdf:type rdfs:Datatype . xsd:date rdfs:subPropertyOf rdf:lform . xsd:date rdfs:drange _:1 . dc:date rdfs:drange _:1 . xxx dc:date "2002-02-14" . Have a nice weekend! ;-) Patrick -- Patrick Stickler Phone: +358 50 483 9453 Senior Research Scientist Fax: +358 7180 35409 Nokia Research Center Email: patrick.stickler@nokia.com
Received on Friday, 15 February 2002 12:21:35 UTC