- From: Ivan Herman <ivan@w3.org>
- Date: Wed, 10 Dec 2008 13:49:24 +0100
- To: Richard Cyganiak <richard@cyganiak.de>
- CC: public-rdfa@w3.org, W3C RDFa task force <public-rdf-in-xhtml-tf@w3.org>
- Message-ID: <493FBAD4.4070406@w3.org>
Hi Richard, because the distiller is a piece of software, and was written by me, therefore distiller has bugs:-) That is part of the ABox:-) Caveat: I am on a trip right now, I am not sure when I can handle this. Please, bear with me... Richard Cyganiak wrote: [snip] > > > 1. Behaviour of RDFa markup on <html> and <body> elements. Let's say my > file contains these markup bits (doctype, namespace declarations etc > omitted): > > <html rel="foaf:maker" rev="foaf:homepage"> > <body about="#me"> > ... > > I expect this to generate these triples: > > <> foaf:maker <#me> . > <#me> foaf:homepage <> . > > But what I get from the RDFa Distiller: > > <> foaf:maker <#me> . > <#me> foaf:homepage <> . > <> foaf:maker <> . > <> foaf:homepage <> . > > Why is this? > At first glance, this does look like a bug. I will have to check that. Actually, there might be a slight issue in the spec, though: the spec explicitly says "if the element is the head or body element then act as if there is an empty @about present" but it does not say anything about the html element... > > 2. Behaviour of datatype="" when the content includes *RDFa* markup. > Let's say I have this in my HTML: > > <p about="#me" property="bio:olb"> > I work at > <a rel="foaf:workplaceHomepage" href="http://www.deri.ie/">DERI > Galway</a>. > </p> > > This works as expected, it creates two triples, a bio:olb triple whose > value is an rdf:XMLLiteral, and a foaf:workplaceHomepage triple whose > value is the DERI URL. > ??? I have put up your test file on the web by removing the @datatype: http://www.ivan-herman.net/Misc/2008/cyg-test.html and what I get via the distiller is: <http://www.ivan-herman.net/Misc/2008/cyg-test.html#me> bio:olb "I work at <a href=\"http://www.deri.ie/\" rel=\"foaf:workplaceHomepage\" xml:lang=\"en\" xmlns=\"http://www.w3.org/1999/xhtml\">DERI Galway</a>."^^rdf:XMLLiteral. Ie, the foaf:workplaceHomepage triple is _not_ generated. And that is correct! As Toby said in his reply, if a property is found and a literal is generated, all processing should stop at that point... I remember that we had lots of discussion on that issue in the group, but that is indeed the final conclusion. > Now I want the bio:olb as a plain literal, so I add datatype="" to the > <p> tag. This creates the expected plain literal, but the > foaf:workplaceHomepage triple disappears. Annoying! Is this the correct > result? I sort of hope that it's a bug in the RDFa Distiller... > Again, this behaviour is actually the right one. Labelling a subtree as a @property means that this subtree is, sort of, removed from the RDFa processing. > > 3. Double predicates. Just to confirm, is it always allowed to have > multiple CURIEs in the CURIE-accepting properties? > > rel="foo:prop1 bar:prop2" > rev="foo:prop1 bar:prop2" > property="foo:prop1 bar:prop2" > typeof="foo:prop1 bar:prop2" > > I assume that all of these are legal and will result in two triples > instead of one? > Yes. > > That's all for now. Finally, in case that some of the folks who > influenced the design of RDFa on this list: Let me say that I'm > impressed with the result. Thank you! Ivan > Obviously a lot of thought went into every > detail of the language and the result is pleasing and elegant. Finally, > here's an RDF syntax that does not suck and makes RDF publishing fun! > > Cheers, > Richard > -- Ivan Herman, W3C Semantic Web Activity Lead Home: http://www.w3.org/People/Ivan/ PGP Key: http://www.ivan-herman.net/pgpkey.html FOAF: http://www.ivan-herman.net/foaf.rdf
Received on Wednesday, 10 December 2008 12:50:07 UTC