- From: Antoine Zimmermann <antoine.zimmermann@emse.fr>
- Date: Thu, 10 Nov 2011 15:41:20 +0100
- To: public-rdf-wg@w3.org
When RDF Concepts describe what the terms in RDF means, it must follow the RDF Semantics, which is (iii). In RDF Semantics, "foo"^^http://ex.com/whatever denotes a resource. This resource can only be known according to a datatype map and only if the datatype map contains a pair (http://ex.com/whatever,ddd). Otherwise, it is unknown. There is the notable exceptions of datatypes xsd:string and rdf:XMLLiteral, which must always be interpreted as required by XSD and RDF respectively (previously not true for xsd:string). However, there is no way in RDF/RDFS to state that an IRI does not denote a datatype. The text should rather say something like: "If <x,ddd> is not in the datatype map then a typed literal with datatype IRI x is interpreted as an unknown resource." This requires that the notion of datatype map be introduced before. Note that the unknown resource denoted by a literal of unsupported type may not be a literal value at all (e.g., it could be a person). AZ Le 09/11/2011 21:53, RDF Working Group Issue Tracker a écrit : > > RDF-ISSUE-79 (undefined-datatype): What is the value of a literal whose datatype IRI is not a datatype? [RDF Concepts] > > http://www.w3.org/2011/rdf-wg/track/issues/79 > > Raised by: Richard Cyganiak > On product: RDF Concepts > > The RDF Concepts spec (in both 2004 and 1.1 versions) does not answer the question what's the value of a literal where the datatype IRI doesn't actually denote a datatype, like<"foo",http://example.com/not-a-datatype>. This is surprising, as there is a section that normatively defines the value of *all other* literals. > > There are many possibilities: > > (i) the spec leaves it undefined > (ii) that's not a valid RDF graph > (iii) it's a valid RDF graph, but the value, if any, is unknown > (iv) it's a valid RDF graph, and the literal is ill-typed > > This should be made explicit. > > The status quo is (i). I believe that the model theory says it's (iii). > > > > -- 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, 10 November 2011 14:41:57 UTC