Re: Complexity of RDFa

On 29/03/10 13:19, Rob Vesse wrote:
> Hi all

Hi Rob,

> Perhaps this may just be a case of not having worked with RDFa for long
> enough to feel truly comfortable with it – what do other people in the
> community think?

I think this covers much of it. You're also being pretty nice about html 
and css, when I find inspect element / firebug essential wrangling tools.

RDF serialisations always feature a degree of variability, as it is the 
nature of graph syntaxes. Once you add a few shortcuts to the syntax 
that increases hugely, but having multiple ways write the same thing 
isn't necessarily a problem. Try working with n-triples all the time. 
Syntactic sugar is a good thing.

(As an aside there are occasions where I pick syntax based on shortcuts. 
turtle is often more pleasant than rdf/xml, but unless you're working 
with bnodes it's painful to work with nested structures. rdf/xml is much 
clearer for hierarchies)

However I do sympathise. Treated purely as an RDF serialisation RDFa is 
fairly eccentric, and on occasions baffling. Here's a reduction of 
something I (shamefully) wrote:

     <p about='#a' xmlns:ex="http://example.com/ns#">
         <span rev='ex:rev' about='#b' typeof='ex:Type'>
             <span property='ex:toAttribute' content='In attribute'>
                 <span property='ex:toText'>In text</span>
             </span>
         </span>
     </p>

That second line was _not_ a good idea. Having worked with RDFa for a 
while now I'd never include that much on one element.

Divorcing RDFa from the host language is misleading, though. The variety 
of methods to produce the same triples are artifacts of the RDFa use 
cases. As I mentioned elsewhere we've been using RDFa to type the links 
between University of Bristol staff and organisations. All it took was 
the addition of rel="foaf:member" and rev="foaf:member" to links in 
their respective web pages. Rev is one of those awkward bits of RDFa, 
but in the right place it makes perfect sense.

RDFa will benefit from another trip through the w3c process to mature it.

Damian

Received on Monday, 29 March 2010 13:45:47 UTC