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Re: CLASS and ROLE

From: José Manuel Cantera Fonseca <jmcf@tid.es>
Date: Wed, 18 Apr 2007 14:18:37 +0200
To: Steven Pemberton <steven.pemberton@cwi.nl>
Cc: RDFa <public-rdf-in-xhtml-tf@w3.org>
Message-id: <46260C9D.4020807@tid.es>

Steven, Ben and the rest who answer,

Thanks for your responses!!!

 From a theoretical standpoint your comments about the class attribute 
make sense, but looking more into the reality nowdays, it is true the 
fact that the class attribute is used by authors to convey presentation. 
That is the reality, the state of the practice, regardless of what HTML 
4.01 says. And I think that it could be an issue having things like

<p class="myclassUseInCSS foaf:person">

why ? Because, two different people are going to be "touching" the same 
attribute. The graphic designer who provides the final look and feel of 
a page and the metadata provider who annotates a page. That's an issue. 
Even, the designer will think that some styles are missing in the CSS 
... Summarizing, if an attribute can be multivalued, and that values 
have not the same meaning, as it is the case, it can be a nightmare.

Also imagine that my page is generated by a server side script and that 
for some reason the class attribute is generated dynamically, I have to 
take care in generating also the "semantic values of the class 
attribute", not only the presentation values. It's going to be a mess.

New attributes are needed !!!

Best regards

Steven Pemberton escribió:
> On Tue, 17 Apr 2007 08:58:45 +0200, José Manuel Cantera Fonseca 
> <jmcf@tid.es> wrote:
>
>> The class attribute has
>> presentational connotations but not semantic connotations.
>
> Actually that is not the case. Although the major user of @class is 
> CSS, the definition of class says:
>
> "The class attribute has several roles in HTML:
> * As a style sheet selector (when an author wishes to assign style 
> information to a set of elements).
> * For general purpose processing by user agents."
> http://www.w3.org/TR/html401/struct/global.html#adef-class
>
> So this use is "general purpose processing". Microformats use it in a 
> similar way, and there are several other processing programs that I 
> have come across that use class in a similar way, to convey extra 
> meaning.
>
>     <div class="note">
>
> is about meaning, not about presentation (even if there is a 
> stylesheet that uses that class).
>
>> You are mixing things
>> in a very dangerous and confusing manner.
>
> I think the confusion is likely to arise because most people have 
> forgotten about that line "For general purpose processing by user 
> agents", and think it is something to do with CSS.
>
>> Regarding the role attribute the same comment applies. Role attribute 
>> has
>> connotations related to accessibility but not to semantics.
>
> Again, this is not the case either. @role was *designed* to convey 
> extra semantics about an element, that amongst other things would be 
> very useful for accessibility.
>
> But look at http://www.w3.org/WAI/PF/GUI/roleTaxonomy-20060221.html
> The abstract *says* that it is about semantics, that is being used in 
> this case for accessibility. In fact there is even a "note" value to 
> role, especially to indicate that an element represents extra 
> information on a page.
>
>
>
>
Received on Wednesday, 18 April 2007 12:22:43 GMT

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