- From: Mark Baker <distobj@acm.org>
- Date: Thu, 11 Sep 2008 01:01:05 -0400
- To: noah_mendelsohn@us.ibm.com
- Cc: "Steven Pemberton" <steven.pemberton@cwi.nl>, "Ben Adida" <ben@mit.edu>, www-tag@w3.org
Noah, On Tue, Sep 9, 2008 at 5:52 PM, <noah_mendelsohn@us.ibm.com> wrote: > * You then quote the RDFa Syntax and Processing draft: "There SHOULD be a > @version attribute on the html element with the value 'XHTML+RDFa 1.0;". > Let's for the moment ignore that it's a SHOULD and consider the case where > @version is indeed set this way. Is there something in RFC 3236 or XHTML > 1.0 to the effect that "a value in the @version attribute of the HTML > element is a key that can be used to identify additional specification(s) > that provide normative interpretations for markup beyond that which is > standardized for XHTML itself?" As best I can tell, XHTML delegates > discussion of the <HTML> element to HTML 4.01, and that in turn says that > the version attribute is deprecated! [1] Is there something normative in > either XHTML or M12N that says "go looking for a specification that seems > to have been written by the authority responsible for the namespace used > in the new markup?". > > So, I'm still missing some crucial connections.= I think there is one connection missing; RDFa extends the meaning of rel (and rev) attribute values in a manner which HTML doesn't licence. Often, IME, doing that sort of thing is a really bad idea, but not always. In this case, rel attribute values are a fairly simple element of HTML, as they're just a list of opaque strings from a small dictionary, and AFAIK, there's no processors which try to treat them as anything more than that. So RDFa's introduction of special meaning to a colon - a character unused in that dictionary - is effectively harmless. That's not the end of the story of course, because while RDFa isn't self-descriptive, it should be made so. What that requires is an update to HTML to anoint the special meaning of ":" in link types; http://www.w3.org/html/wg/html5/#linkTypes So for your draft, you might consider expanding 4.1 to explain in more detail what it means to extend an existing media type self-descriptively in both the short and long term. Mark.
Received on Thursday, 11 September 2008 05:01:41 UTC