Re: RDFa Question, Clarification

On 20 Aug 2008, at 13:48, Martin McEvoy wrote:

> What I mean Is I DON'T want to reference ANY namespaces.

Technically RDFa doesn't use namespaces, but uses prefixes, but for  
the purposes of this discussion, the two are close enough to be used  
interchangeably.

Theoretically, RDFa does allow for the use of unprefixed terms, which  
get treated as belonging to the "default prefix". However, only a  
small set of terms (basically the union of the link types defined in  
HTML 4.01 and XHTML 2) are defined in the default default prefix.  
Yes, I did use "default default" deliberately in the last sentence,  
because theoretically if you could point the default prefix to  
somewhere other than its default URI, then you could create your own  
unprefixed terms. But RDFa does not define a method for changing the  
default prefix, so you're stuck with the default default prefix.  
Perhaps the editors of a future version of RDFa may add a method for  
authors to change the default prefix, but if that were to happen, it  
would be a long way down the line.

> The reason why I ask this question Is because In the Microformats  
> Community one of the FIRST thing's that you learn is that  
> Namespaces for Content  has failed and should be avoided, so much  
> so that even discussing namespaces in Microformats is a "Taboo"  
> subject.
>
> see: http://microformats.org/wiki/namespaces-considered-harmful


I think you'll find that the opinions found on that page are far from  
unanimously held, even within the microformats community, let alone  
the semantic web community as a whole. Namespaces would have made the  
"title" debate surrounding hAudio a non-issue, but alas namespaces  
were ruled out of microformats at a very early stage and seem  
unlikely to make a return.

Even if RDFa could be used without prefixes (and indeed it can if the  
only relationships you wish to describe are those from the HTML/XHTML  
predefined link types), there is still the bigger issue that the RDFa  
attributes are not valid in legacy HTML 4.01 and XHTML 1.0. Any time  
a proposal that does not validate against one of those  
recommendations is raised on uf-discuss it is shot down pretty quickly.

-- 
Toby A Inkster
<mailto:mail@tobyinkster.co.uk>
<http://tobyinkster.co.uk>

Received on Wednesday, 20 August 2008 14:32:56 UTC