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Re: [httpRange-14] What is an Information Resource?

From: Pat Hayes <phayes@ihmc.us>
Date: Tue, 18 Dec 2007 10:16:50 -0800
Message-Id: <p0623093ac38dbdf9f859@[192.168.1.6]>
To: Mikael Nilsson <mikael@nilsson.name>
Cc: noah_mendelsohn@us.ibm.com, "Sean B. Palmer" <sean@miscoranda.com>, www-tag@w3.org

>On tis, 2007-12-18 at 02:36 -0800, Pat Hayes wrote:
>>  >I can't for the world see how numbers and RDF graphs can fall into the
>>  >same category.
>>
>>  They are both mathematical abstractions. An RDF
>>  graph is defined to be a mathematical set: its
>>  not a data structure or an expression.
>
>Ok, let's accept that argument.
>
>What harm would be done by returning 200 Ok with an RDF/XML
>serialization of this set when asked?

None. But then lets be clear: what that URI 
denotes, in this case, is the (information 
resource which emits the) RDF/XML serialization, 
not the graph itself.

Most of the time, we can be sloppy and call this 
'the graph' or maybe 'a copy of the graph'. But 
sometimes we shouldn't be sloppy, when it matters.

Use case. Lets see: imagine two serializations of 
the same graph, and one of them is altered by a 
POST, or maybe its server goes down so that one 
gets a 404 response. This should not be described 
as the RDF graph being altered or having 
vanished. Graphs aren't the kind of thing one can 
alter or have vanish.

Pat

>
>For things like Jupiter, I can see a clear problem - the thing vs. a
>description of the thing. It makes a difference which you are referring
>to. There are a number of use cases that break when returning a HTML
>document when asked for Jupiter.
>
>But the RDF/XML is not *about* the RDF Graph in the same way, and I
>can't seem to find any issue with returning 200.
>
>What is the use case that breaks?
>
>I've stated before that the IR discussion needs to be grounded in
>use-cases, not theory. In other words, we need to *define* IRs in a way
>that supports our use cases, not the other way around.
>
>/Mikael
>
>
>
>--
><mikael@nilsson.name>
>
>Plus ça change, plus c'est la même chose


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Received on Tuesday, 18 December 2007 18:17:17 GMT

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