- From: Antoine Zimmermann <antoine.zimmermann@emse.fr>
- Date: Thu, 17 Nov 2011 09:41:51 +0100
- To: public-rdf-wg@w3.org
Richard, Le 16/11/2011 22:13, Richard Cyganiak a écrit : > Hi Antoine, > > On 15 Nov 2011, at 21:23, Antoine Zimmermann wrote: >>> if<bar> owl:sameAs<baz>, and<baz> is an IRI in the datatype >>> map, then "foo"^^<bar> may have a well-defined value even if >>> the IRI<bar> is not in the datatype map. >> >> Assuming that owl:sameAs was in the RDF/RDFS spec, this even would >> not make "foo"^^<bar> be interpreted identically as "foo"^^<baz>. >> The interpretation of typed literals is not influenced by anything >> in the ontology, even in OWL. "foo"^^<bar> is always interpreted >> as L2V(D(<bar>))("foo") according to the datatype map D. >> >> FYI, look at section 4.2 of the OWL 2 RDF-based semantics: >> >> "IL is a mapping from typed literals "s"^^u in V to their >> denotations in IR, where IL("s"^^u) = L2V(d)(s), provided that d is >> a datatype of D, IS(u) = d, and s is in the lexical space LS(d); >> otherwise IL("s"^^u) is not in LV." > > That just requires that *d* (the datatype) is in the datatype map, > not that *u* (the IRI) is in the datatype map. If I have<u> > owl:sameAs<v>, then it follows that IS(u)=IS(v). If (v,d) is in the > datatype map, then it follows that IS(v)=d, which gives us IS(u)=d > without u being in the datatype map. > > That's how I read it anyways. Damn, you're correct! So I guess we have an agreement finally. --AZ >> So the interpretation of "s"^^u (or "foo"^^<bar>) is in the value >> space of<bar> if and only if<bar> is in the datatype map > > If my reasoning above is correct, then it doesn't require that<bar> > is in the datatype map. It requires that<bar> denotes d, and that d > is in the datatype map. > >> Otherwise it is not in LV > > (That's actually not a requirement that I can find anywhere in RDF > Semantics. RDF Semantics says that, if a literal's datatype IRI > doesn't denote a datatype, then the literal “is treated as before”, > it denotes “some unknown thing”. In other words, its denotation is > entirely unconstrained, and interpretations that map the literal to a > member of LV are fine. So the wording you quote looks a bit like a > bug in OWL2 to me.) > >> I'm just saying that the word "value" may be misunderstood. For >> instance, I would not consider a person to be a value. > > I don't think there's any basis for that. There's nothing *formally* > wrong with defining a datatype whose lexical space is social security > numbers, whose value space is citizens, and whose L2V mapping > involves the social security database. > > Best, Richard > -- Antoine Zimmermann ISCOD / LSTI - Institut Henri Fayol École Nationale Supérieure des Mines de Saint-Étienne 158 cours Fauriel 42023 Saint-Étienne Cedex 2 France Tél:+33(0)4 77 42 66 03 Fax:+33(0)4 77 42 66 66 http://zimmer.aprilfoolsreview.com/
Received on Thursday, 17 November 2011 08:42:29 UTC