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Re: XBL is (mostly) W3C redundant, and CSS is wrong W3C layer for semantic behavior *markup*

From: John Lewis <lewi0371@mrs.umn.edu>
Date: Fri, 3 Jan 2003 07:24:45 -0600
Message-ID: <167169958278.20030103072445@cda.mrs.umn.edu>
To: www-style@w3.org

Shelby wrote on Friday, January 3, 2003 at 12:33:49 AM:

> Notice that this definition of semantics is very broad. It does not
> differentiate the the semantics of a header from the opening
> sentence of a paragraph. Both "briefly describes the topic of the
> section it introduces"

> Thus some of the important semantics of header, as different from
> first sentence of paragraph, are open to interpretation.

> Some parsers might ignore the headers entirely and merge them as
> first sentence of first paragraph.

CSS can do that by changing the display value of a header to "run-in".
That doesn't change the definition of header elements, it simply
changes their *appearance*. Changing the display value of all headers
to "none" does not mean header elements have no meaning. They still
have meaning as defined in HTML--they're just not presented to the
user.

<http://www.w3.org/TR/REC-CSS2/visuren.html#run-in>

I think you're confusing semantics as defined by HTML with semantics
as interepreted by a reader. For example, using CSS, I could change
the display value (and other values) of nearly every tag in HTML so
that to the reader, <em> is a header, <h1> is a paragraph, and
<strong> is a blockquote. That does not and cannot change the meaning
of those elements as defined in HTML, even though it would fool the
average reader with CSS enabled.

> That is totally different than changing the rendering such as font
> of a header. One is semantically significant, and the other is
> merely presentation property. This is a grey area, and especially
> the header is a poor example to analyze because it is so broad.

Could you prove, or at least explain, how changing the display value
of an element is "semantically significant"?

>>>>> Shelby Moore wrote:
>>>>> CSS selectors allows one to select elements of markup based on 
>>>>> attributes which are not related to *semantics*.
>>>>
>>>> Ian Hickson responded:
>>>> As an editor of the W3C Selectors Specification, I assure you,
>>>> that is most definitely not the intention of CSS selectors. 
>>>  
>>> Ian's "assurance" was false.
>>
>> There are no attributes that are not related to semantics, since
>> attributes are part of an element's meaning.

> False. Font can be set on a paragraph and font has nothing to do
> with the semantics of paragraph. This is 3rd time I have mentioned
> that font is not semantically related to paragraph.

> John Lewis has written in this thread "CSS doesn't need to know the
> markup languages it's applied to, or any markup language at all;
> that's the beauty of it. Knowledge of the markup language's elements
> is contained in the CSS author, where it belongs.".

> John Lewis also restated in another way, "CSS selectors match
> elements without regard to the elements' semantics"

Attributes are not selectors. I agree with your "Font can be set on a
paragraph," etc., but I also agree with Ian's original reply.

>> Absolutely, just as CSS can style tags [sic] that have no
>> specification. That doesn't mean those elements suddenly gain some
>> sort of meaning.

> CSS is not and should not be involved in providing meaning. That is
> my point.

Agreed. In fact, CSS cannot provide, change, or erase meaning, which
means changing display values cannot change meaning. I don't think Ian
disagrees.

-- 
John
Received on Friday, 3 January 2003 08:26:08 GMT

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