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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: Fri, 11 Sep 2009 12:24:03 +0100
Cc: "public-rdf-in-xhtml-tf.w3.org" <public-rdf-in-xhtml-tf@w3.org>
Message-Id: <11BC1B89-DFD2-4F26-AE29-ECE1D84B6E56@jenitennison.com>
To: Shane McCarron <shane@aptest.com>
Shane,

We definitely need the wording clarified here then. Certainly I read  
"If the [current element] does contain a @rel or @rev attribute..." as  
talking about the existence of the rel/rev *attributes* as distinct  
from the existence of rel/rev *values*.

As I see it, there are five scenarios:

   1. the attribute is there and contains one or more valid CURIEs
   2. the attribute is there and contains things that look like CURIEs  
but aren't
   3. the attribute is there and doesn't contain anything that looks  
like a CURIE (eg just whitespace)
   4. the attribute is there and is empty
   5. the attribute is missing

It's clear that there's a difference in behaviour in the setting of  
the new subject and current object resource between 1 and 5. What's  
not at all clear is which of these two behaviours you get with 2, 3,  
and 4.

I'd interpreted your proposal as being that 2 would be treated (so far  
as setting new subject and current object is concerned) as 5 and 2 & 4  
would be treated as 1. But actually you seem to be proposing that 2, 3  
and 4 should all be treated as 5.

Mark seems to be arguing that 2, 3 and 4 should all be treated as 1; I  
find his argument very persuasive.

Jeni

On 10 Sep 2009, at 23:15, Shane McCarron wrote:

> Jeni,
>
> No - that is not what is currently specified (in my opinion), nor  
> what my proposal would do.  Specifically, the third <span> should  
> create the triple:
>
> <> ex:test3 "Test" .
>
> Because the @rel is treated as if it is not present at all.  There  
> are no semantics in RDFa for an empty @rel.
>
> 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
>>>
>>>
>>>
>>>
>>
>
> -- 
> 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
Received on Friday, 11 September 2009 11:24:39 GMT

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