- From: Richard Cyganiak <richard@cyganiak.de>
- Date: Tue, 4 Sep 2012 20:36:57 +0100
- To: Ivan Herman <ivan@w3.org>, Antoine Zimmermann <antoine.zimmermann@emse.fr>, Dan Brickley <danbri@danbri.org>, Richard Smith <richard@ex-parrot.com>, Jeremy Carroll <jeremy@topquadrant.com>
- Cc: public-rdf-comments Comments <public-rdf-comments@w3.org>
Ivan, Antoine, Dan, Richard, Jeremy, I guess I like the idea of informatively linking to both the 2006 SWBP Note on datatypes [1] and to the OWL 2 datatype definition mechanism [2], stating that both XML Schema and OWL 2 provide facilities for formally defining RDF datatypes, but that support for neither mechanism is required for RDF. Jeremy: Is [1] still considered up-to-date, or should we avoid drawing attention to it? Antoine, Ivan, Dan: Perhaps one of you wants to take a stab at drafting a sentence that could be inserted into the Datatypes section [3] as another Note? Cheers, Richard [1] http://www.w3.org/TR/swbp-xsch-datatypes/ [2] http://www.w3.org/TR/owl2-syntax/#Datatype_Definitions [3] http://dvcs.w3.org/hg/rdf/raw-file/default/rdf-concepts/index.html#section-Datatypes On 4 Sep 2012, at 18:38, Ivan Herman wrote: > Dan, > > the question is of course justified, but I should also add that, in fact, very very few people use xmls schema datatype definitions together with RDF, too. In both cases the difficulty is identical: to understand and process those datatypes an external 'tool' has to be brought in: either an xml schema or an owl processor... Mainly in a non-XML RDF world (ie, as Richard said, with a diminishing usage of RDF/XML) the chance of using XML schema based derived datatypes is getting smaller and smaller in my view. > > I find the OWL 2 datatype definition possibilities one of the most interesting and potentially important part of OWL 2. I actually wish the relevant part of the specification was also made more known and possibly used in isolation; at present it is burried in the overall OWL 2 spec, which is of course not an easy read... > > (Maybe it is worth some extra blog/note) > > Ivan > > --- > Ivan Herman > Tel:+31 641044153 > http://www.ivan-herman.net > > (Written on mobile, sorry for brevity and misspellings...) > > > > On 4 Sep 2012, at 15:37, Dan Brickley <danbri@danbri.org> wrote: > >> On 4 September 2012 21:11, Antoine Zimmermann >> <antoine.zimmermann@emse.fr> wrote: >>> FWIW, OWL 2 has a feature to define custom datatypes that can be written >>> completely in RDF, without using XML Schema. >>> >>> Your example for Chapman codes can be written as follows, in Turtle syntax: >>> >>> @prefix geo: <http://www.example.com/geo#> >>> @prefix xsd: <http://www.w3.org/2001/XMLSchema#> >>> @prefix owl: <http://www.w3.org/2002/07/owl#> >>> @prefix rdfs:<http://www.w3.org/2000/01/rdf-schema#> >>> >>> geo:chapman-code a rdfs:Datatype; >>> owl:equivalentClass [ >>> a rdfs:Datatype; >>> owl:onDatatype xsd:string; >>> owl:withRestriction ( [xsd:pattern "[a-zA-Z]{3}"] ) >>> ] . >> >> Interesting! Are many of these showing up "in the wild" yet? >> >> Dan >> >
Received on Tuesday, 4 September 2012 19:37:27 UTC