- From: Toby Inkster <tai@g5n.co.uk>
- Date: Wed, 23 Sep 2009 12:54:21 +0100
- To: Philip Taylor <pjt47@cam.ac.uk>
- Cc: Manu Sporny <msporny@digitalbazaar.com>, HTMLWG WG <public-html@w3.org>, RDFa mailing list <public-rdf-in-xhtml-tf@w3.org>
On Wed, 2009-09-23 at 09:52 +0100, Philip Taylor wrote:
> So I believe these attributes (rel, rev, content, href, src) should
> only be permitted on the elements that HTML5 currently permits them
> on.
Certainly it would be wise to consider the appearance of @href and @src
on elements HTML5 does not currently permit them on to be
non-conforming.
They're allowed anywhere in XHTML+RDFa for essentially two reasons:
- RDFa was written with XHTML 2.0 compatibility in mind. In
XHTML 2.0 it was planned that any element could be a link,
and any could embed external images. Hence the attributes
were allowed anywhere.
- RDFa is also written to avoid mentioning specific HTML
elements as much as possible. This is because it is
intended to be usable with non-HTML markup languages, like
SVG, ODF, DocBook, etc. The XHTML+RDFa processing algorithm
only defines any special behaviour for <head> and <body>.
However, disallowing @rel, @rev and @content from appearing on arbitrary
elements would break current content which relies on the fact that they
can, and break very useful RDFa authoring patterns.
--
Toby A Inkster
<mailto:mail@tobyinkster.co.uk>
<http://tobyinkster.co.uk>
Received on Wednesday, 23 September 2009 11:55:15 UTC