- From: Julian Reschke <julian.reschke@gmx.de>
- Date: Wed, 18 Feb 2009 12:49:17 +0100
- To: Henri Sivonen <hsivonen@iki.fi>
- CC: Ben Adida <ben@adida.net>, Karl Dubost <karl@la-grange.net>, Mark Birbeck <mark.birbeck@webbackplane.com>, Sam Ruby <rubys@intertwingly.net>, Kingsley Idehen <kidehen@openlinksw.com>, Dan Brickley <danbri@danbri.org>, Michael Bolger <michael@michaelbolger.net>, public-rdfa@w3.org, RDFa mailing list <public-rdf-in-xhtml-tf@w3.org>, Tim Berners-Lee <timbl@w3.org>, Dan Connolly <connolly@w3.org>, Ian Hickson <ian@hixie.ch>
Henri Sivonen wrote: > On Feb 17, 2009, at 19:24, Julian Reschke wrote: > >> Henri Sivonen wrote: >>> ... >>> Although this looks like a non-problem in browsers because the >>> Namespace-unaware DOM Level 1 view is available, it is a technical >>> problem with APIs that only provide a Namespace-aware representation. >>> For example, XOM doesn't allow attributes called xmlns:foo in the >>> data model. Non-browser consumers are important, and it should be >>> perfectly reasonable to use XOM in such a consumer. >>> ... >> >> Could you elaborate what exactly the problem with XOM is? I didn't get >> it from this paragraph. > > It doesn't represent XML attribute spelled "xmlns:foo" in the XML source > code as attributes in the API. Thus, if you write a XOM-based consumer > for RDFa-in-XML as currently defined, you can't just swap the parser to > an HTML5 parser and have it work. It appears to me that this could be considered to be either a bug in the HTML5 parser, or in XOM. > You'd need to change the HTML5 parser to expose attributes spelled > "xmlns:foo" in the same way XML namespace mapping context is exposed. > Such a change would be a non-zero change with non-zero cost making the > line of argument that RDFa using attributes spelled "xmlns:foo" involves > zero cost/change to HTML5 implementors bogus. > > Note that the Validator.nu HTML Parser currently exposes a XOM tree, so > a parser exposing XOM is not a theoretical construct. None of the Yes, I know that. > currently drafted HTML5 features need the change that exposing > xmlns:foo-based RDFa would require for consistency with the exposure of > xmlns:foo in XML. So is there a precise requirement in HTML5 that mandates how a parser must expose xmlns:foo when producing SAX events, for instance? >> That doesn't seem to be true. An implementation of setAttribute (L1) >> would just need to know that an attribute named "xmlns:*" is something >> special, and internally map it. > > Well, internally mapping it specially would be a non-zero change/cost on > browsers making the line of argument that there's no cost or action > required on behalf of browser vendors bogus. I would assume that a sane implementation that supports both DOM level 1 and DOM level 2 already does that. But I've been wrong on the smarts of DOM implementations before :-) BR, Julian
Received on Wednesday, 18 February 2009 11:50:08 UTC