- From: James Graham <jg307@cam.ac.uk>
- Date: Wed, 16 Aug 2006 11:11:45 +0100
Matthew Raymond wrote:
>> The role attribute currently describes behavior, and is added so that
>> users with disabilities know what the behavior for a given element is,
>> according to well-known semantics. CSS is supposed to be for
>> presentational. In your scenarior, will there be any way to easily know
>> whether one of the items in the class attribute describes the behavior
>> is purely presentational?
>
> Well, authors are not supposed to put in purely presentational class
> names to begin with
Show me a spec that says that in a normative way. It is merely a "best
practice". Class names, in general, are meaningless and meaningful class
names should not be part of the core specification.
> I have yet to hear an
> argument with regards to why |class| can perform the same functions that
> |role| can, especially given the allowance in the HTML 4.01 spec for
> "general purpose processing".
Of course, if you plan to put all the semantics of a document in the
class names, we could do away with many elements. Do you object to <div
class="h1"> as a replacement for <h1>?
>> Otherwise, both authors and machine processors
>> will be easily confused by it.
Eh?
> The values for |role| are nothing more than a new set of class names,
> and there is nothing preventing the user from putting in unidentified
> |role| values for presentational purposes and then styling them via CSS
> using attribute selectors. So aside from being mildly harder to select
> from CSS, |role| values are potentially no more semantic than |class|
> values.
Authors can misuse anything. <h1 style="font-size:12px;
font-weight:normal;">This is the main text of my document put in a
heading so that search bots think that it's really relevant and useful</h1>.
> However, let's assume that people would only use semantic values in
> |role|. What becomes of |class|? We use it only for styling? That won't
> work, because HTML is supposed to be semantic.
We use it for it's purpose - to provide hooks to enable presentational
languages to couple to arbitrary groups of elements on a page. This kind
of non-semantic hook is _necessary_ so that the temptation to abuse the
semantic elements is greatly reduced.
> So what we end up doing is replacing |class| with an attribute named
> |role| that has more rules but otherwise does the same thing.
No. We add an attribute which conveys specific semantics ("this element
is being used as a UI widget of a particular type). We standardize some
well-researched values for that element that are applicable to the needs
of non-visual UAs in the real world.
Received on Wednesday, 16 August 2006 03:11:45 UTC