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Re: Underline element.

From: Patrick H. Lauke <redux@splintered.co.uk>
Date: Fri, 28 Dec 2007 05:59:42 +0000
Message-ID: <477490CE.2010903@splintered.co.uk>
To: public-html@w3.org

Andrew Fedoniouk wrote:

> For human this markup:
>   <button><u>O</u>pen</button>
> plus associated behavior has clear semantic value and
>   <button accesskey="^O">Open</button>
> is just nothing - user simply has no clue about that accesskey.
> Information that is unknown to particular person has
> semantic value of zero for that person, isn't it?

It's the user agent's duty to expose the semantics to the end user in an 
appropriate format. And, as suggested, since current UAs don't expose 
the accesskey, scripting can be used to patch this.
The semantics might be unknown to the user, but not to the user agent.

Compare this to your use (if I understand it correctly from your 
previous message): you use presentational markup to suggest a possible 
behaviour visually to the user, but rely on scripting to actually enact 
that behaviour. In your case, the semantics (the meaning or intent of 
that underline) are unknown to the user agent, so the user agent can't 
sensibly expose it to the end user beyond simply following the 
presentational markup.

Say a UA wants to provide functionality that lists all current keyboard 
shortcuts for the current page/document. Using @accesskey semantics, it 
can simply parse the document and list all attributes found. But it 
wouldn't be able to simply list all <u> elements, as they may have been 
used for presentational purposes (as per their definition).

This is the same reason why heading elements should be used to denote 
the structure of a document, rather than simply using presentational 
markup that makes text bigger/bolder/etc. The former has actual semantic 
meaning, while the other only has presentational value that, once 
rendered, may lead the user to *infer* semantic meaning...but it's not 
unequivocal for UAs to interpret.

I'd still say that using the more accurate semantics of the markup 
language, and - where necessary - patching the visual presentation 
accordingly is preferable to doing the opposite.

Patrick H. Lauke
re·dux (adj.): brought back; returned. used postpositively
[latin : re-, re- + dux, leader; see duke.]
www.splintered.co.uk | www.photographia.co.uk
Co-lead, Web Standards Project (WaSP) Accessibility Task Force
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Received on Friday, 28 December 2007 06:00:02 UTC

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