Re: @about/@instanceof discussion

Ben Adida wrote:
> Ivan Herman wrote:
>> I just sent a reply and after I hit the button did I realize that there
>> is an important use case that will go wrong with your approach. If I have
>>
>> <img src="bla" rel="foaf:depiction"/>
>>
>> I can have the triple
>>
>> <> foaf:depiction <bla>
>>
>> all right, but there is no easy way to set the type of the image (<img>
>> cannot have children in the XHTML model...).
> 
> That's exactly my point!
> 
>> Having said that: after having fought with @instanceof for a while now,
>> I have the impression that no matter what we decide, there will be a use
>> case where setting the type is awkward. We may have to accept a
>> sub-optimal solution, ie, that not everybody will be happy:-)
> 
> I disagree... Tell me what you think would be hard to express, and I'll
> express it with my rules :)
> 

:-)

Well, I can _express_ in XHTML+RDFa the issue above with Manu's rules,
though by repeating a URI:

<img src="bla" rel="foaf:depiction"/><span about="bla" instanceof="a:b"/>

And, in fact, that is the point. I believe (no proof, though) that we
_can_ express anything we really want in RDFa whichever way we move with
@instanceof, and without going out of our way. There are edge cases, of
course, but well... In this sense, choosing simplicity for the design is
a good guideline, too:-)

Ivan


> -Ben

-- 

Ivan Herman, W3C Semantic Web Activity Lead
Home: http://www.w3.org/People/Ivan/
PGP Key: http://www.ivan-herman.net/pgpkey.html
FOAF: http://www.ivan-herman.net/foaf.rdf