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Re: RDF-ISSUE-8 (IRI vs URI): Incorporate IRI-s into the RDF documents [Cleanup tasks]

From: Mischa Tuffield <mischa.tuffield@garlik.com>
Date: Mon, 7 Mar 2011 16:12:19 +0000
Cc: RDF Working Group WG <public-rdf-wg@w3.org>
Message-Id: <EB38A3FF-0CBE-4353-82D9-57D1564D98E6@garlik.com>
To: Pat Hayes <phayes@ihmc.us>
Hello, 

<snip/>

On 5 Mar 2011, at 15:26, Pat Hayes wrote:

> 
> On Mar 5, 2011, at 5:19 AM, RDF Working Group Issue Tracker wrote:
> 
>> 
>> RDF-ISSUE-8 (IRI vs URI): Incorporate IRI-s into the RDF documents [Cleanup tasks]
>> 
>> http://www.w3.org/2011/rdf-wg/track/issues/8
>> 
>> Raised by: Ivan Herman
>> On product: Cleanup tasks
>> 
>> The IRI Spec[1] is from 2005, and it may be necessary to retrofit it to RDF. Eg, what is the relationship between "http://résumé.example.org" and "http://xn--rsum-bpad.example.org"? Are they the same resource or not? Note that SPARQL has something on that[2]...
> 
> SPARQL says "IRI (corresponds to the Concepts and Abstract Syntax term "RDF URI reference")"  

As far as I am aware, URI Ref definition came out before the RFC defining IRI. They are "pretty similar" insofar as the URIRef work was second guessing what IRIs would be, but they didn't managed to get it 100% correct. 

> 
> Is this strictly correct? That is, are IRIs in fact just URI references by another name? If not (as I suspect) can anyone briefly outline the points of difference?

No, they are not the same thing, the differences lie in terms of what characters get encoded and which don't. One example is the backtick character `, which doesn't need to be % encoded when creating an IRI but it does need to be when generating a URI Ref. I sent an email to the SWIG mailing list about this a while back [1], whereby people pointed out the history, and some of the subtle differences between the two. 

Mischa

[1] http://lists.w3.org/Archives/Public/semantic-web/2010Jul/0426.html 

> 
> Pat
> 
>> 
>> [1] http://www.ietf.org/rfc/rfc3987.txt
>> [2] http://www.w3.org/TR/rdf-sparql-query/#docTerminology
>> 
>> 
>> 
>> 
> 
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Received on Monday, 7 March 2011 16:13:00 UTC

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