- From: Jeremy Carroll <jjc@hpl.hp.com>
- Date: Tue, 17 Apr 2007 12:15:24 +0100
- To: Michael Kifer <kifer@cs.sunysb.edu>
- CC: Dave Reynolds <der@hplb.hpl.hp.com>, Sandro Hawke <sandro@w3.org>, Christian de Sainte Marie <csma@ilog.fr>, RIF WG <public-rif-wg@w3.org>
Michael Kifer wrote: >> Michael Kifer wrote: >>> Thanks. I think this answers my question. >>> My concern was that there might be an IRI, x, such that its encoding as a URI, >>> f(x), is not equivalent to x *as an IRI*. >>> You seems to be saying that this is not possible. >> Sandro's Kanji example illustrates that this is possible. If an IRI i >> isn't itself a URI then the URI encoding of it must be different. Unless >> you specify some normalization f(i) and i are different. > > Of course they are different. I was talking of them being *equivalent*. > > We may or may not want to introduce an equality relation on such equivalent > IRIs (note: equality != identity), but regardless of that if > a ~ b as URIs and not as IRIs then using IRIs as an extension of URIs would > be problematic. If this doesn't happen then I see no problem. > The usual operation to use is 'character by character comparison' This has the following effects, which are well suited to using IRIs or URIs as identifiers, and under which URIs are a true subset of IRIs. a) If X and Y compare as equivalent as URIs then they compare as equivalent as IRIs b) If X and Y compare as equivalent as IRIs, and X is a URI then so is Y, and they compare as equivalent as URIs character by character comparison is done after having dealt with low level details like character encoding which are input/output issues dealt with by XML (for example) Jeremy -- Hewlett-Packard Limited registered Office: Cain Road, Bracknell, Berks RG12 1HN Registered No: 690597 England
Received on Tuesday, 17 April 2007 11:15:48 UTC