[wp-hackers] WordPress eXtended RSS DTD

[Otto]

On Fri, Jul 18, 2008 at 9:46 AM, Xavier Borderie <xavier at borderie.net> wrote:
> Back in 2003, Meg Hourihan was writing the now-defunct Kinja.com, and
> wrote a rant about OPML's failing DTD (OPML having been designed by
> the same developer as RSS2, as you know), rant that I think applies
> just as well to RSS' lacking DTD, or from there extends (heh, get it?
> xml? extends?) to just about any badly documented XML format, and how
> developers tend to understand the way they work as they see fit to
> their own purposes.
> http://meg.hourihan.com/2003/08/no-extends
>
> I think "discrepancy" is the word I'm looking for here, but then again
> I'm French, what do I know? :)

Her rant relates to attributes and all that. Basically, XML that can
be extended. However, the solution to her problem is XML namespaces.
Which WordPress uses correctly in the export file.

A WXR file is a valid RSS 2.0 file. It has extra data in it, which all
takes the form of new tags in the wp: namespace. A parser that doesn't
understand that namespace would ignore it.