Re: RDFa in HTML issues wiki page created

Julian Reschke wrote:
> Shane McCarron wrote:
>> Just so I am clear - do you personally have a requirement that a 
>> document with embedded RDFa always emit the same triples, regardless 
>> of its progeny?  In other words, if I have a document that is HTML5 
>> with RDFa and parse it, and a similar document that is XHTML + RDFa 
>> and parse it, would you expect *exactly* the same triples to be 
>> emitted?  Do you require this?  Is it a deal breaker if the triples 
>> differ?
> 
> I think it would be very bad if the same @rel value produces different 
> triples depending on what media type/doctype it appears in. Even if 
> there's an out-of-band way to discover that they are the same.

What makes this especially poignant is the question as to how Drupal 
pages (with a doctype of xtml and a media type of text/html) are to be 
processed.  Such pages are generally, but not unfailingly, well formed.

When well formed, such pages are technically valid XHTML; but there are 
zero browsers on the planet which interpret such a document as such.

Given this state, and the evident proclivity of users to copy and paste 
markup into such documents, I would think that it would be a rather good 
idea for there to be a subset of RDFa (and by subset, I mean things like 
disallowing the use of two prefixes which differ only in case in the 
same scope of the same document) which can be processed either as XHTML 
or HTML and produce the same triples.

Perhaps there can be different rules for XHTML served as 
application/xhtml+xml, or HTML with a non-XHTML doctype.

> BR, Julian

- Sam Ruby

Received on Tuesday, 26 May 2009 16:16:53 UTC