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RE: microformats, profiles, and taking back rel/class names [standardizedFieldValues-51]

From: Rhys Lewis <rhys@volantis.com>
Date: Tue, 17 Jul 2007 01:20:14 -0700 (PDT)
To: <noah_mendelsohn@us.ibm.com>, "'Dan Connolly'" <connolly@w3.org>
Cc: "'www-tag'" <www-tag@w3.org>
Message-ID: <002301c7c84b$98a6d040$0e03c80a@volantisuk>

+1 on unease.

Doesn't the WAI 'role' attribute [1] serve the same sort of purpose that
the HTML WG wants to ascribe to the 'preferred' values of class?. There
are implementations of 'role' for Firefox. I think it's still in the XHTML
2 spec too.

Best wishes
Rhys

[1] see for example
http://www.w3.org/WAI/PF/GUI/roleTaxonomy-20060508.html

-----Original Message-----
From: www-tag-request@w3.org [mailto:www-tag-request@w3.org] On Behalf Of
noah_mendelsohn@us.ibm.com
Sent: 16 July 2007 20:45
To: Dan Connolly
Cc: www-tag
Subject: Re: microformats, profiles, and taking back rel/class names
[standardizedFieldValues-51]


Dan Connolly wrote:

> I suppose the HTML WG has the right to "take back" @rel and @class 
> values, but I'm uneasy about it.

Me too, very uneasy.  Let me repeat here something that I said on the TAG
call, originally intended in jest, but I'm now thinking it might be a
serious proposal.  The current HTML 5 draft [1] says of the class
attribute:

"Authors may use any value in the class attribute, but are encouraged to
use the values that describe the nature of the content, rather than values
that describe the desired presentation of the content."

Perhaps to be a true guide to the intended use of this attribute in the
presence of technologies like microformats it should say:

"Authors may use any value in the class attribute, but are encouraged to
use the values that describe the nature of the content, rather than values
that describe the desired presentation of the content. 

NOTE: although this version of the HTML specification provides no specific
meaning for any particular class attribute tokens, future versions of this
specification, other specifications, or common public practice will likely
assign preferred connotations to some.  (For example, at the time of this
writing, the token 'vcard' is coming into common use for designating
information about people, companies, organizations, and places. [2])
Because no means is here provided of identifying in advance which tokens
will later be given such preferred meanings, there is a risk that any
document using any value(s) for class attribute tokens will later prove
incompatible with widely deployed conventions."

In short:  we know this is "broken" in this way.  Implicitly, we believe
the benefits outweigh the risks, but we are at least warning you of the
problem. 

Now, I personally am not at this point convinced that the benefits of
retroactively assigning such universal meanings do outweigh the risks, but
I am increasingly convinced that we should warn users if this is likely to
happen.

Noah

[1] http://www.whatwg.org/specs/web-apps/current-work/#classes
[2] http://microformats.org/wiki/hcard




--------------------------------------
Noah Mendelsohn
IBM Corporation
One Rogers Street
Cambridge, MA 02142
1-617-693-4036
--------------------------------------
Received on Tuesday, 17 July 2007 08:20:30 GMT

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