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Re: Semantic content negotiation (was Re: expectations of vocabulary)

From: Richard Newman <r.newman@reading.ac.uk>
Date: Sun, 30 Jul 2006 09:55:18 -0700
Message-Id: <F3F5378F-69B1-47FE-94E6-C38B0C8214FE@reading.ac.uk>
Cc: "'Semantic Web'" <semantic-web@w3.org>
To: "Xiaoshu Wang" <wangxiao@musc.edu>

   I was refuting your claim that "The only thing that is not  
dereferenceable is literal values". This is far from accurate. Good  
practice is quite another thing entirely.

   Both Henry and I already pointed out that the FOAF docs will  
return RDF if you ask for it.

   The hash-or-slash debate *is* relevant here. Dereferencing




   which is the base ontology URL, and looks at the fragment ID on  
the client side. Dereferencing


   tries to fetch an entirely different URL, which in my case is  
highly likely to be a 404. If you choose slashes, you either need a  
smart server (e.g., URIQA) or a smart crawler on the client. I prefer  
the former, but Apache ain't it.


On  30 Jul 2006, at 7:18 AM, Xiaoshu Wang wrote:

>>> Are you sure you are talking RDF? The only thing that is not
>>> dereferencable is literal values because they are not URI.  But
>>> literal can only be an object, not subject and property.
>> Not true. Only a subset of URIs are dereferenceable, and even
>> fewer are dereferenceable to yield RDF. The following are a
>> few examples:
> If the URI is a property and dereference it does not return a URI  
> is not a
> good practice.  I remember that the TAG is working on what is  
> supposed to be
> put in the namespace.  In FOAF's case, at least the URI is  
> dereferenable.
> But the returned type is HTML.  Here, if GRDDL is standardized, it  
> will
> still return an RDF document.  No one is required to make any URI
> dereferenable.  But the best practice should recommend so.  If an  
> RDF engine
> should follow all the links to retrieve all RDFs.

>> <dereferenceable RDF URL> + #propertyName
>> I often use slashes instead of hashes, and what you get from
>> a web server serving up a representation of that URI is
>> probably not a fragment of the ontology.
> This hash/slash debate is irrelevant here.
Received on Sunday, 30 July 2006 16:55:28 UTC

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