[whatwg] xml:lang and xmlns in HTML

[Robert Sayre]

On 12/1/06, Ian Hickson <ian at hixie.ch> wrote:
>
> Aaaaah! Sorry, I hadn't understood this. So, to put it another way, you
> want a way to introduce author-specific semantics into your HTML
> documents?

Almost. I want to understand why non-HTML5-defined semantics would be
harmful. I don't think we're in danger of each web author inventing
their own elements.

>
>
> > <http://listserver.dreamhost.com/pipermail/whatwg-whatwg.org/2006-December/008171.html>
> >
> > But it is a question, not a request. I don't want to request something
> > that would be harmful. So, what is the downside of the example in that
> > earlier email?
>
> Well, SVG itself would arguably be bad because it is poor from a semantic
> standpoint.

HTML is poor from a semantic standpoint. Doesn't bother me. I make
layouts with tables and headings with bold and lists with sequences of
<p> tags. I'll probably never write pretty HTML, and I wouldn't be
surprised if billions of people are just like me. Is HTML5 going to
prevent me from authoring in that style?

> However, as far as generic author-defined semantics go, that's
> what the "class" attribute is for.  Microformats.org, for example, use the
> "class" attribute to introduce calendar semantics and the like into HTML.
> You take the closest fitting HTML element, semantically, and then augment
> it with your classes.

Yes, I understand those, and I think they might work. Why is it
harmful to allow the document I posted in the mail below as well?

<http://listserver.dreamhost.com/pipermail/whatwg-whatwg.org/2006-December/008171.html>

>
> Introducing author-defined markup into HTML would be bad from a semantic
> and accessibility point of view because UAs would not be able to derive
> any meaningful information or default presentation from the content, and
> thus users would not be able to access the data.

Right, so no one will use those things unless browsers support them.
Is that bad?

-- 

Robert Sayre