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Re: AW: XHTML 2.0 and hreflang and type

From: Lachlan Hunt <lhunt07@postoffice.csu.edu.au>
Date: Sun, 16 Nov 2003 02:52:01 +1100
Message-ID: <3FB64BA1.6060200@postoffice.csu.edu.au>
To: W3C HTML List <www-html@w3.org>

Oskar Welzl wrote:

>>The point I tried to obliquely raise in my
>>previous post is "Why has type been changed from being 
>>descriptive to being
>>proscriptive?" 
>>    
>>
>
>i'm getting interested in this point, too. the more i think of it, the worse it gets... 
>...we should probably also make people reconsider @type.
>  
>
>>I see no reason why type should be changed from being advisory as it is in
>>HTML4 to being proscriptive as it is in the XHTML2 draft.
>>    
>>
>
>agreed.
>  
>
  I don't understand why you think @type has been made 'proscriptive'?  
It just doesn't make sense.  Unless you actually meant to write 
'prescriptive' which has a completely different meaning, and makes more 
sense in that context.  However, even if you did mean prescriptive, I 
still have to disagree.

  In the HTML 4.01 specs [1], it states the following:

type = content-type [CI]
...Authors who use this attribute take responsibility to manage the risk 
that it may
 become inconsistent with the content available at the link target address.

  This means that, since only one type could be specified, then only one 
type should be available on the server, and it should be exacly what is 
specified in the document.  Though it was only advisory, it was 
restrictive in that only one type could be specified, even though 
multiple might be available.
  In the XHTML 2.0 version, since additional types can be specified, it 
is still advisory (since it is just advising the UA that more types are 
available), though it is less restrictive.

  For example, if and image was available in png, gif and jpg format, 
how could that be using the HTML 4.01 version of @type in XHTML 2.0?

You could write, as someone suggested previously:
<p src="image" type="image/png">
    <p src="image" type="image/gif">
        <p src="image" type="image/jpg">
        Image description here...
        </p>
    </p>
</p>

  But being able to write that in a less cumbersome way, that gives the 
UA more choice about which type to get is much better, and IMHO, easier 
(for simplicity, I have excluded the q values):
<p src="image" type="image/png, image/gif, image/jpg">Image description 
here...</p>

  How is this not being advisory?  IMO, it's giving more advice than was 
previously available in HTML 4.01.
  Maybe, including the q values makes it more prescriptive, but I don't 
fully understand them myself.

[1] http://www.w3.org/TR/html401/struct/links.html#adef-type-A

CYA
...Lachy
Received on Saturday, 15 November 2003 10:56:07 UTC

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