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Re: Does @instanceof apply to @href?

From: Ben Adida <ben@adida.net>
Date: Mon, 21 Jan 2008 13:51:11 -0800
Message-ID: <479513CF.9060600@adida.net>
To: Manu Sporny <msporny@digitalbazaar.com>
CC: RDFa <public-rdf-in-xhtml-tf@w3.org>

Manu Sporny wrote:
> You seem to be arguing for the same thing that Mark is arguing for
> (minus @resource and @src):

No, I did not say that: you separated two issues that I believe cannot
be separated, which takes my arguments out of context.

I'm saying that *if* we decide to have @href/@resource completing
hanging @rel (and I'm against it), then I think the logical corollary is
that @instanceof then applies to @href/@resource in those cases, and I'm
worried about the complexity that results from this.

I note that you were recently quite unhappy with the possibility that
@instanceof would apply to @href/@resource (which is reminiscent of my
proposal). Have you changed your mind?

Here's a more complete example:

<div about="#me" rel="foaf:knows">
   <div instanceof="foaf:Person" property="foaf:name">
      Mark
   </div>
</div>

I believe everyone agrees that this gives:

<#me> foaf:knows _:bn0 .
_:bn0 rdf:type foaf:Person .
_:bn0 foaf:name "Mark" .

What happens if I add an @href (or @resource) to the inner div?

<div about="#me" rel="foaf:knows">
   <div href="#mark" instanceof="foaf:Person" property="foaf:name">
      Mark
   </div>
</div>

According to the "@href completes @rel" proposal, that gives:

<#me> foaf:knows <#mark> .

So, what happens to the rdf:type and foaf:name triples? Do they hang on
a bnode that is no longer connected:

_:bn0 rdf:type foaf:Person .
_:bn0 foaf:name "Mark" .

or do they now apply to <#mark>?

<#mark> rdf:type foaf:Person .
<#mark> foaf:name "Mark" .

If they hang on a bnode, then this seems inconsistent: adding the @href
breaks up the graph structure in a way that adding @about at that exact
location does not.

If they hang off <#mark>... now you've got @property using @href from
the same element as its subject.

I'm honestly trying to see it your way, but I think you're arguing based
on the simplest possible markup of a leaf @href. Once you expand the
markup a bit and add some child nodes, it looks anything but "simpler."

-Ben
Received on Monday, 21 January 2008 21:51:21 GMT

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