- From: Lachlan Hunt <lachlan.hunt@lachy.id.au>
- Date: Sun, 13 May 2007 22:48:11 +1000
- To: "Patrick H. Lauke" <redux@splintered.co.uk>
- CC: www-html@w3.org
Firstly, why is it that you chose to change the subject back to
presentational elements, instead of being productive and focussing the
the table headers issue?
I've already asked 3 times for examples to be provided that would
support the addition of the headers attribute (and provided some
myself), trying to help you strengthen you case for adding it, but each
time you have bypassed question entirely. I will not ask again, but I
would appreciate your cooperation this time.
Patrick H. Lauke wrote:
> Lachlan Hunt wrote:
>> No, that's backwards. Nothing gets added or retained without some
>> evidence that it's needed. Otherwise, you could use that argument to
>> get us show why the <foo> element isn't needed, instead having the
>> ones who asked for it explain why it is.
>
> Which seems to me what's happening with refinements for <b>, <i>, <sup>,
> <sub> etc
No, that is not what is happening with those elements. They do have
many valid use cases. <b> and <i> were thoroughly explained in the
recent threads, so I will not go into them again.
http://lachy.id.au/log/2007/05/b-and-i
<sub> and <sup> have valid use cases too.
* Simple mathematical expressions
e.g. <var>E</var> = <var>m</var><var>c<sup>2</sup></var>
<var>x<sub>1</sub></var>
* Chemical compunds. e.g. H<sub>2</sub>O
* Footnote references
* etc.
Even the the spec makes use of <sub> in several places for good reasons.
See, for example, this algorithm.
http://www.whatwg.org/specs/web-apps/current-work/#header-and-data-cell-semantics
Their names may come from the typographical conventions, but those
conventions are used for very specific reasons. It's quite reasonable,
in a general purpose markup language like HTML, to provide simple
elements that cover those cases reasonably well, rather than requiring
specific elements for each individual case.
Like <b> and <i>, the specific semantics of <sub> and <sup> can be
determined by the reader from the context of their use. Omitting them
or replacing them with something like <span> would be far less semanitic
and less useful for users.
If we were to drop them from HTML, we'd create a problem. How would all
of those use cases (including ones I didn't list) be marked up? <sub>
and <sup> already solve that problem reasonably well, there's no reason
to replace them with something new.
If it can be shown that such context sensitive semantics is a problem in
practice, then that may be a reason to provide a way to more
specifically refine the semantics (e.g. x<sup type="math">2</sup>). But
there hasn't yet been any evidence to show that it is a problem, and so
nothing would be solved by doing that.
--
Lachlan Hunt
http://lachy.id.au/
Received on Sunday, 13 May 2007 12:48:28 UTC