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RE: INSEE releases OWL ontology and RDF data for geographical entities

From: Eric van der Vlist <vdv@dyomedea.com>
Date: Sun, 06 Aug 2006 10:40:47 +0200
To: Xiaoshu Wang <wangxiao@musc.edu>
Cc: 'Dan Connolly' <connolly@w3.org>, semantic-web@w3.org, public-xg-geo@w3.org
Message-Id: <1154853647.9274.19.camel@localhost>
Xiaoshu,

Le samedi 05 août 2006 à 17:45 -0400, Xiaoshu Wang a écrit :
[...]
> The reason for me to raise this question is this.  Unlike hash URI, the
> namespace URI can not be "inferred" or "guessed" from a URI itself.  For
> instance, a URI of http://foo.com/bar can be constructed with namespace
> http://foo.com/, http://foo.com/b or http://foo.com/ba coupled with local ID
> of "bar", "ar" and "r", respectively.

That's just a minor detail since all this would be bad practises, but in
the same horrors show category, I don't see why you couldn't define
namespace names such as http://foo.com#b or http://foo.com#ba and hashes
do not allow to "infer or guess" (as you say) namespaces names more
reliably than slashes :) !

Note that the RDF recommendation gives a rule about how this kind of
"inference":

"It is recommended that implementors of RDF serializers, in order to
break a URI into a namespace name and a local name, split it after the
last XML non-NCName character, ensuring that the first character of the
name is a Letter or '_'. If the URI ends in a non-NCName character then
throw a "this graph cannot be serialized in RDF/XML" exception or
error."

This means that if your namespace URI ends with a letter, you won't have
roundtrip.

Eric

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Received on Sunday, 6 August 2006 08:41:17 GMT

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