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Re: Agenda Topic / Issue: Clarify the meaning of "ignore" with respect to attributes that have no legal value

From: Jeni Tennison <jeni@jenitennison.com>
Date: Thu, 10 Sep 2009 22:08:45 +0100
Message-Id: <1500ABD8-19E5-4209-9C3F-CCFB042D024C@jenitennison.com>
To: "public-rdf-in-xhtml-tf.w3.org list" <public-rdf-in-xhtml-tf@w3.org>
One issue with having switches based on the *presence* of the rel  
attribute is that, if I recall correctly, IE reports rel, rev, lang  
and xml:lang as being present, but empty, on every element.

There's currently some code in rdfQuery that deals with this by  
mapping empty values into undefined (as if the attribute wasn't  
there), but I believe that it's legacy code given that I have to parse  
the serialised start tag of the element in IE anyway.

Jeni

On 10 Sep 2009, at 21:47, Jeni Tennison wrote:

> Can I also clarify, just to round this out, that in this test case  
> from Philip:
>
> <p xmlns:ex="http://example.org/">
>  <span property="ex:test1" href="http://example.org/href">Test</span>
>  <span rel="ex:test2" property="ex:test3" href="http://example.org/href 
> ">Test</span>
>  <span rel="" property="ex:test5" href="http://example.org/ 
> href">Test</span>
> </p>
>
> the triples are:
>
> (from the first <span>)
>  <http://example.org/href> ex:test1 "Test" .
>
> (from the second <span>)
>  <> ex:test2 <http://example.org/href> .
>  <> ex:test3 "Test" .
>
> (from the third <span>)
>  <> ex:test5 <http://example.org/href> .
>
> In other words that the empty rel attribute is treated differently  
> from a rel attribute that contains only illegal CURIEs, which is  
> treated the same as a missing rel attribute.
>
> Thanks,
>
> Jeni
>
> On 10 Sep 2009, at 20:36, Shane McCarron wrote:
>
>> Laurens,
>>
>> In general I agree but see below:
>>
>> Laurens Holst wrote:
>>> Op 8-9-2009 10:28, Shane McCarron schreef:
>>>> So, for example,
>>>>
>>>> <a rel="blah:blah" href="file.html">something</a>
>>>>
>>>> Would never generate triple, because the prefix "blah" is not  
>>>> defined, so the system MUST act as if there was no @rel at all.
>>>
>>> Hm, so just to be clear:
>>>
>>> <a rel="blah:blah foo:bar" href="file.html">something</a>
>>>
>>> Would not generate a triple, but:
>>>
>>> <a rel="blah:blah foo:bar" href="file.html" xmlns:foo="http://example.org 
>>> ">something</a>
>>>
>>> and
>>>
>>> <a rel="blah:blah bar" href="file.html">something</a>
>>>
>>> Would?
>> Nearly.  rel="bar" is not a defined reserved word, so that wouldn't  
>> raise a triple either.
>>>
>>> ~Laurens
>>>
>>
>> -- 
>> Shane P. McCarron                          Phone: +1 763 786-8160  
>> x120
>> Managing Director                            Fax: +1 763 786-8180
>> ApTest Minnesota                            Inet: shane@aptest.com
>>
>>
>>
>>
>
> -- 
> Jeni Tennison
> http://www.jenitennison.com
>
>
>

-- 
Jeni Tennison
http://www.jenitennison.com
Received on Thursday, 10 September 2009 21:09:24 GMT

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