W3C home > Mailing lists > Public > public-rdf-in-xhtml-tf@w3.org > July 2008

Re: RDFa in HTML 4

From: Toby A Inkster <tai@g5n.co.uk>
Date: Thu, 17 Jul 2008 22:15:59 +0100
Message-Id: <E1EF2326-7B06-497E-B14F-3F3ABEBA9310@g5n.co.uk>
To: public-rdf-in-xhtml-tf@w3.org

Manu Sporny wrote:

>    <div curieprefix="dcterms http://purl.org/dc/terms/
>                      media http://purl.org/media#
>                      audio http://purl.org/media/audio#"
>         about="#a-song" typeof="audio:Recording">

I've suggested it before, but I'll suggest it again. RFC 2731, which  
was put forward by the Dublin Core crowd many years ago, already  
offers an HTML-compatible method for defining prefixes for metadata  
terms. RFC 2731 has been embraced by eRDF. The syntax is:

     <link rel="schema.dct" href="http://purl.org/dc/terms/">

These definitions are document wide though, so it may be necessary to  
refine the syntax to allow them to be scoped to particular elements.  
Perhaps using:

     <link about="#section-1" rel="schema.dct"
         href="http://purl.org/dc/terms/">

to define the CURIE prefix "dct" to be only valid within the element  
with id="section-1". (This creates an additional limitation that for  
an element to have CURIE prefix definitions scoped to it, it must  
have an ID attribute, but this isn't a major limitation.)

> There is no HTML4 + RDFa validator, and until we can point web
> developers to a tool that validates HTML4 + RDFa, we should not
> encourage them to use RDFa in HTML4.

I posted this on this mailing list just yesterday - a page using a  
DTD based on HTML 4.01 Strict, but with RDFa attributes added.

http://buzzword.org.uk/2008/html4plus-example.html

This *will* validate in the W3C validator, though it would be nice if  
there was a way to make the "Unable to Determine Parse Mode!" warning  
disappear. It *will* parse correctly in most (all?) RDFa parsers.

> The goal is to enable HTML 4 + RDFa as quickly as possible.


Well, Cognition has supported RDFa in HTML 4 (using RFC 2731 for  
CURIE prefixes) since February.

http://buzzword.org.uk/cognition/

-- 
Toby A Inkster
<mailto:mail@tobyinkster.co.uk>
<http://tobyinkster.co.uk>
Received on Thursday, 17 July 2008 21:17:01 GMT

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