W3C home > Mailing lists > Public > w3c-rdfcore-wg@w3.org > September 2001

Re: RDF IDs, N-Triples URI encoding (was Re: URI terminology demystified)

From: Dave Beckett <dave.beckett@bristol.ac.uk>
Date: Thu, 20 Sep 2001 16:43:02 +0100
To: Dan Connolly <connolly@w3.org>
cc: Jeremy Carroll <jjc@hplb.hpl.hp.com>, w3c-rdfcore-wg@w3.org
Message-ID: <6621.1001000582@tatooine.ilrt.bris.ac.uk>
>>>Dan Connolly said:
<snip/>
> I don't understand how that's relevant. We decided
> that
> 	rdf:ID="foo"
> is short for
> 	rdf:about="#foo"
> and hence rdf:ID *is* subject to the same rules for
> turning Unicode strings into URI references.

OK, I missed the affect of that issue on the syntax refactoring doc.
I'll add it to the next version.

<snip/>

> n-triples has the distinctive feature that URI references go right
> in the file without any sort of quoting or other mangling,
> except putting <>'s around them. (relative URI references do get
> absolutized.) Recall: URI references consist of US-ASCII characters
> only. No URI reference has an umlaut in it.
> 
> string literals in n-triples need quoting, but URI references
> do not.
> 
> So n-triples shows the *result* of taking a unicode string
> from an rdf:resource attribute and converting it to a URI reference.

It looks like I got the URI encoding grammar and words all wrong in
N-Triples too, as discussed in the comments I referred to:

> > see the discussion on www-rdf-comments starting at
> >   http://lists.w3.org/Archives/Public/www-rdf-comments/2001JulSep/0245.html
> > and subsequent responses by me.
> 
> I see:
> 
> |Looking; CHARMOD says, for URIs:
> |
> |  A W3C specification that defines new syntax for URIs, such as a new
> |  kind of fragment identifier, MUST specify that characters outside
> |  the US-ASCII repertoire are encoded in URIs using UTF-8 and
> |  %HH-escaping
> |  -- http://www.w3.org/TR/charmod/#sec-URIs
> 	-- DaveB, Tue, 18 Sep 2001 10:38:59 +0100
> 
> That text from the CHARMOD spec is perhaps misleading: no W3C
> specification can define new syntax for URIs. That's what
> RFC2396 is for. W3C specs can be defined that *use* URIs.
> n-triples is such a format. Luckily, as I say, URIs in
> n-triples don't need any form of quoting.

thus all the above is accepted.

Dave
Received on Thursday, 20 September 2001 11:43:03 EDT

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