- From: Eric van der Vlist <vdv@dyomedea.com>
- Date: Sat, 20 Oct 2001 08:34:46 +0200
- To: Patrick.Stickler@nokia.com
- Cc: www-rdf-interest@w3.org
Patrick.Stickler@nokia.com wrote: >>> <rdf:type rdf:resource="x:dataType"/> >>> > >><rant> >>Although many vocabularies are doing so I am usually very >>reluctant to >>use qualified names in attributes or element values. >> > > The use of qnames as attribute values or in content data aside, > the above resource is a URV namespace, hence a URI. Yes, I > know it looks like a qname. Perhaps it should have been written > as "x:dataType:". If you haven't already, please read my X-Values > proposal (I don't want to repeat it here). > > http://lists.w3.org/Archives/Public/www-rdf-comments/2001OctDec/0088.html My reluctance about using namespace prefixes is not specific to RDF, even though I think that RDF (with RELAX NG mentioned in my previous post) is one of the few examples of specs which are sane in this respect. I have nothing about using prefixes and writing: <a uri-shortcut="x='http://example.org'" b="x:anything"/> is something I wouldn't consider as unsane. It's doing the same with namespace prefixes, especially when this is not needed for the markup itself such as in: <a xmlns:x='http://example.org' b="x:anything"/> which I consider as unsane since it's creating a dependency from the content of a document to its markup. The namespaces rec acknowledge that a prefix has no value and is only a shortcut for a URI. The languages and API acknowledge this as well and XPath but also SAX2 and DOM Level2 provide an easy access to the URI but *not* to the prefix (and they are clean and right doing so). > > This brings up the question, which I asked in another thread > yesterday, about whether one can treat a URI scheme prefix > or URN/URV namespace prefix as a URI. > > E.g. are "http:" or "urn:issn:" URI's? Can I use them to > make statements about those schemes? If not, why not? > (all RDF parsers I've used seem quite happy to treat them as URIs) > > And personally, I think the ability to use qnames in attributes > is highly desireable and will have a great impact on future user > acceptance of RDF XML serializations (which are *very* cumbersome > to write manually -- or require the use of ENTITY tricks to achieve > the same level of compression and convenience as qnames but > introduce yet another representation for a URI). XML Schema got it > right IMO by allowing qnames as values of URI typed attributes. I don't think so and I hope RDF will stay "sane" in this respect. Two specifications (Canonical XML and XPointer) have already hit the wall because of this issue and I think it would be high time to acknowledge that it's a bad practice :=) ... My 0.02 Euros Eric > Cheers, > > Patrick > > -- > Patrick Stickler Phone: +358 3 356 0209 > Senior Research Scientist Mobile: +358 50 483 9453 > Nokia Research Center Fax: +358 7180 35409 > Visiokatu 1, 33720 Tampere, Finland Email: patrick.stickler@nokia.com > > > > > -- Rendez-vous à Paris pour le Forum XML. http://www.technoforum.fr/Pages/forumXML01/index.html ------------------------------------------------------------------------ Eric van der Vlist http://xmlfr.org http://dyomedea.com http://xsltunit.org http://4xt.org http://examplotron.org ------------------------------------------------------------------------
Received on Saturday, 20 October 2001 02:34:28 UTC