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Re: Conneg representation equivalence

From: Pierre-Antoine Champin <swlists-040405@champin.net>
Date: Thu, 11 Mar 2010 21:34:52 +0100
Message-ID: <4B9953EC.9050508@champin.net>
To: Toby Inkster <tai@g5n.co.uk>
CC: "nathan@webr3.org" <nathan@webr3.org>, Linked Data community <public-lod@w3.org>
On 11/03/2010 11:04, Toby Inkster wrote:
> On Thu, 2010-03-11 at 02:24 +0000, Nathan wrote:
>> If I have multiple representations of a resource which I consider
>> equal, let's say one of each of the following: RDF+XML, RDF+N3, SVG
>>
>> Then should all three representations be considered equivalent?
> 
> They certainly *could* all represent the same thing. Whether they *do*
> represent the same thing is a judgement call.

Well, if they are accessible via the same URI, using content
negociation, then my reading of the HTTP specification is that they
*must be* representations of the same resource.

Not sure what Nathan means by "equivalent"...

>> Is it correct that all representations must have consistent fragment
>> identifiers in order to be considered equivalent? 
> 
> A fragment identifier should not identify different things in different
> representations. (Though it may be unrepresented in some or all of the
> representations.)

Is that so?
If I recall correctly the URI RFC (no internet when writing the mail,
sorry), the semantics of fragments identifiers depends on the retrieved
content-type. So why would they *have* to identify the same thing?

That being said, I agree it sounds like a good practice. Especially if
you consider an RDF/XML and a Turtle representation of the same RDF
graph... If their fragment identifier were not consistent, that would be
a serious headache... But is this rule written somewhere?

  pa
Received on Thursday, 11 March 2010 22:24:55 UTC

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