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Re: Another way other than @profile, @vocab or @map

From: Ivan Herman <ivan@w3.org>
Date: Wed, 17 Mar 2010 14:03:57 +0100
Message-ID: <4BA0D33D.40202@w3.org>
To: Toby Inkster <tai@g5n.co.uk>, martin@weborganics.co.uk
CC: RDFa WG <public-rdfa-wg@w3.org>
Interesting.

I think, as Mark said, the distinction whether we have a URI or a CURIE
in typeof becomes moot, because we can have both. In other words, I
think what you say is that we use the type URI's trimmed back version as
a URI for a default namespace, so to say.

Personally, if we go that route, I would prefer not to mix the typeof
with that solution, and keep it a separate attribute as Martin proposed
originally. I believe it is cleaner that way. I am not against hacking
in general but this looks like a bit too much of a hack:-( Let alone the
fact that for some vocabularies I may want to have number of typeof-s in
a subtree with different values, and there is a real danger of
inadvertently changing the default namespace, ie, leading to a bunch of
invalid or unwanted triples...

The problem I see that while this indeed may be used to define a bunch
of keywords it does not answer the case when one want to mix
vocabularies. Ie, the user will have to choose one default uri for
keywords and then use @xmlns (or equivalents) for the other
vocabularies. Maybe that is acceptable...

I wonder whether the two mechanisms (this and the @profile discussion we
have) exclude one another. Maybe we can restrict the @profiles to prefix
mappings only and keyword mapping going this route...

Ivan

On 2010-3-16 20:17 , Toby Inkster wrote:
> On Tue, 2010-03-16 at 14:38 +0000, Martin McEvoy wrote:
>> With all the above in mind,  RDFa could I think re-use an attribute
>> name that already exists in htm5, microdata to be more precise
>> "itemtype"[1]. RDFa could be used pretty much like microdata eg:
>>
>> <div itemtype="http://www.w3.org/2006/vcard/ns#" about="#BusinessEntity" 
>> typeof="VCard">
>> <div property="fn">L'Amourita Pizza</div>
>> <div rel="adr">
>> <div typeof="Address">
>> <span property="street-address">2040 Any Street</span>,
>> <span property="locality">Springfield</span>,
>> <span property="postal-code">98102</span>.
>>               Tel: <span property="tel">206-555-7242</span>.
>> <span rel="url" resource="http://pizza.example.com/"></span>
>> </div>
>> </div>
>> </div> 
> 
> I like the general idea, but how about reusing typeof instead:
> 
> <div typeof="http://www.w3.org/2006/vcard/ns#VCard" about="#BusinessEntity">
>   <div property="fn">L'Amourita Pizza</div>
>   <div rel="adr">
>     <div typeof="Address">
>       <span property="street-address">2040 Any Street</span>,
>       <span property="locality">Springfield</span>,
>       <span property="postal-code">98102</span>.
>     </div>
>   </div>
>   Tel: <span property="tel">206-555-7242</span>.
>   <span rel="url" resource="http://pizza.example.com/"></span>
> </div>
> 
> This should be pretty easy to make workable: whenever typeof contains a
> full URI (CURIE versus URI can be determined by checking whether
> xmlns:http has been declared yet), then it sets the default prefix (by
> trimming back to the last non-QName character - in the example above
> '#') for unprefixed tokens. In the case where typeof contains multiple
> tokens (space-separated), then the first one wins.
> 
> This may well be more author-friendly than external profiles; plus it's
> going to make parsing a bit faster, not needing to dereference external
> files.
> 

-- 

Ivan Herman, W3C Semantic Web Activity Lead
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Received on Wednesday, 17 March 2010 13:03:12 GMT

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