Comment on last XHTML 2 draft, section 3.2

I would like to comment on items 4 and 5 of section 3.2:

   4. If a user agent encounters an element it does not recognize, it
      must continue to process the content of that element. If this
      "unrecognized" element uses recognized attributes, those attributes
      must be processed with their usual semantics.
   5. If a user agent encounters an attribute it does not recognize, it
      must ignore the entire attribute specification

First, I have just no idea what means "recognize" in this context. This
verb clearly lacks a definition. Please note it's used in various
other places, before and after items 4&5 of that section still w/o
definition.

If "an element/attribute a user agent does not recognize" means "an
element/attribute a user agent cannot confirm as a valid xhtml2
element/attribute in the current context", then it implies all user
agents must be validating user agents. And this is hopeless, to say the
least.

And if it means "an element/attribute a user agent cannot confirm as
an element/attribute listed in the XHTML2 spec", well, that's probably
useless. What about an element in a non-xhtml namespace ? Is that
"recognized" or not ? If it is, then again user agents must have some
basic level of validation.

I also have this feeling these items were introduced to preserve the
xml purity of the document instance. But it may be counter-productive
if industrial filters designed to transform existing current web sites
using HTML plus extra element sets into XHTML2 cannot be called XHTML2
user agents !

More generally, I think these items are badly designed from a
perspective of language extensibility, that being quite paroxystic for
an XML dialect given the meaning of the leading X...

</Daniel>

Received on Wednesday, 9 August 2006 12:13:52 UTC