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Re: ISSUE-76: If we fixed namespaces, does RDFa still have problems?

From: Henri Sivonen <hsivonen@iki.fi>
Date: Wed, 16 Dec 2009 11:50:44 +0200
Message-Id: <591CCAD5-ED38-42AA-91A2-7BEF206574FC@iki.fi>
To: "public-html@w3.org WG" <public-html@w3.org>
On Dec 15, 2009, at 19:15, Toby Inkster wrote:

> On Tue, 2009-12-15 at 17:20 +0200, Henri Sivonen wrote:
>> On Dec 14, 2009, at 03:29, Manu Sporny wrote:
>> 
>>> Microdata:
>>> 
>>> <div itemscope>
>>> <p>My name is <span itemprop="name">Aryeh Gregor</span>.</p>
>>> </div>
>>> 
>>> RDFa:
>>> 
>>> <div about="#me" vocab="myvocab.html">
>>> <p>My name is <span property="name">Aryeh Gregor</span>.</p>
>>> </div>
>>> 
>>> or
>>> 
>>> <div about="#me" xmlns:myvoc="http://ficticious.url/vocab#">
>>> <p>My name is <span property="myvoc:name">Aryeh Gregor</span>.</p>
>>> </div>
>> 
>> Are these RDFa examples complete without an id="me" somewhere? That
>> is, is baseuri#me supposed to be an imaginary URL that doesn't
>> dereference to a node but is just talked about or is it supposed to
>> point to a node?
> 
> This is a question that's important, but orthogonal to RDFa (it applies
> equally to, say, Microdata's itemid attribute). 
> 
> I'm personally of the opinion that a URI should identify precisely one
> thing, so for the given examples, in an ideal world, there would *not*
> be an id="me" attribute anywhere in the document. If there were such an
> attribute, it would introduce confusion as to what the URI <baseuri#me>
> represents - does it represent a section of a document, or does it
> represent a person called Aryeh Gregor?

This, to me, seems like a fundamental problem with the idea of using http URLs to identify things that cannot actually be accessed using HTTP.

>> * Namespaces are a complication for implementors.
> 
> Not sure if you're referring to consumers or producers. Or perhaps both?

I was thinking of implementors of consuming software, but Namespaces are a complication to implementors of producer software, too.

> As an author of RDFa documents, the one things that does get on my
> nerves is that the use of CURIEs isn't optional.
[...]
> I'm pleased that
> allowing full URIs in currently CURIE-only attributes is planned for the
> next version of RDFa.

Allowing full URIs doesn't address my concerns with CURIEs. I wanted CURIEs to go away. Making them optional for authors doesn't remove the processing side of CURIEs. (When I was advocating full URIs, I was advocating them *instead* of CURIEs, not in *addition* to them.)

-- 
Henri Sivonen
hsivonen@iki.fi
http://hsivonen.iki.fi/
Received on Wednesday, 16 December 2009 09:51:29 UTC

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