Re: what are you saying?

Danny Ayers wrote:
> Mark Birbeck blogged:
>> But RDFa doesn't have any 'values'. It's not like Dublin Core, or
>> hCard, or iCal, or FOAF. It's not a vocabulary, it's a syntax.

This is the crux of the argument, as far as I see it, and I have to
strongly agree with Mark's position. RDFa is not a vocabulary, thus
placing something in @profile doesn't make much sense as @profile is
meant for specifying definitions of vocabularies[1].

When working with the Microformats community, we consistently state that
we will put the vocabulary definition in @profile... which is the
correct thing to do, by my reading of the HTML4.01 specification. This
is because Microformats are more about vocabulary than syntax. Whereas,
RDFa is much more about syntax than vocabulary.

One approach would be to create a vocabulary that specifies the type of
metadata that is embedded in the document, so, we could have something like:

<head profile="http://www.w3.org/profiles/html-metadata">
   <meta name="metadata-flavor" content="xhtml+rdf">
   <meta name="metadata-flavor" content="microformats">
</head>

The above would specify that the current document contains both RDFa and
microformatted data. However, that seems a bit contrived.

Another approach could have us using @class to hint to the user agent
that there is RDFa data in the document, something like:

<div class="xhtml-rdf">... RDFa goes here ...</div>

The first benefit of the second approach is that the author doesn't have
to have access to the entire contents of the web page to hint to a user
agent that RDFa is embedded in the page. The second approach is also
fully compliant with the spirit of the use of @class in the HTML and
XHTML specifications[2], AFAIK.

-- manu

[1]http://www.w3.org/TR/html401/struct/global.html#h-7.4.1
[2]http://www.w3.org/TR/html401/struct/global.html#h-7.5.2

-- 
Manu Sporny
President/CEO - Digital Bazaar, Inc.
blog: Over One Million Songs Available on Bitmunk
http://blog.digitalbazaar.com/2007/10/29/one-million-songs-on-bitmunk/

Received on Thursday, 13 December 2007 15:52:26 UTC