- From: Graham Klyne <GK@Dial.pipex.com>
- Date: Mon, 08 May 2000 21:16:39 +0100
- To: Dan Brickley <danbri@w3.org>
- Cc: www-rdf-interest@w3.org
At 01:59 PM 5/8/00 -0400, Dan Brickley wrote:
>It's not clear where we guarantee that. RDFS says that the model
>corresponding to an RDF Schema shouldn't be changed, but is silent on
>whether alternate syntactic representations might for eg become available
>via content negotiation. This can of course be over-ridden by W3C
>Publication Rules for specs. But I'm inlcined to agree: "it" shouldn't
>change.
Yes! Here you are saying something about an RDF model (an RDF schema),
that it is invariant, and almost the opposite thing about *representations*
of that model, that they may vary.
And these are all, I think, statements that can be represented in RDF.
>Quite. This is one of my concerns with RDF. However squeaky clean the
>model, unless the Web has a clear conceptual model (here's how to
>identify a Web
>_Page_, a Web _Service_ a Web _Site_ etc) the richness of the formal model
>is wasted.
I am doubtful that we can have a clear conceptual model of everything that
RDF can describe -- there is (by design, I understand) too much flexibility
to create paradoxes, etc. Rather like human languages, I think.
But to have a clear conceptual model of those things that matter to
functioning of the web is, I hope, a different matter.
> > rephrased carefully: the interpretation of a fragment identifier w.r.t.
> > an entity body received in response to a GET request to a resource is
> > relative to the MIME type of the entity body.
>
>Thanks for the extra precision: this is exactly the problem I'm concerned
>with. The mime type may differ from day to day and client to client, which
>is a problem from an RDF perspective as we treat URI References as if they
>made sense when lifted out of such contexts.
I agree. I think that, when dealing with namespaces for RDF (and other
purposes), we should be very cautious about using fragment identifiers at
all. For myself, I would tend to avoid fragment identifiers altogether in
namespaces -- there are always hierarchical URIs that achieve much the same
effect without the MIME content-type ambiguity.
I.e., instead of:
<foo xmlns:bar="http://xyzzy.com/plugh#">
...
use:
<foo xmlns:bar="http://xyzzy.com/plugh/">
...
#g
(Meaning g's view of the world for any MIME type that recognizes personal
views ?-)
------------
Graham Klyne
(GK@ACM.ORG)
Received on Monday, 8 May 2000 18:39:51 UTC