- From: Mark Baker <distobj@acm.org>
- Date: Wed, 26 Sep 2001 11:59:44 -0400 (EDT)
- To: michael@neonym.net
- Cc: robla@real.com (Rob Lanphier), uri@w3.org
Oops, sorry, missed this one. > On Tue, Sep 25, 2001 at 02:52:50PM -0400, Mark Baker wrote: > > There's different degrees of equivalency at play here. > > > > It is the case that if two HTTP URIs are equal, that they necessarily identify > > the same resource (also see RFC 2616 sec 3.2.3). It is not the case that if > > two HTTP URIs are *not* equivalent (even modulo 2616/3.2.3), that they do > > *not* represent the same resource. The only way to determine whether two > > non equivalent HTTP URI represent the same resource latter is to have > > authoritative info about that equivalence (or lack thereof). One way for > > that authoritative info to be communicated is with an HTTP redirect. > > > > Even the current CTURI draft has the latter problem, as the encoding is not > > canonical. > > This is indeed the case with _all_ URIs. Equivalence of resources across > schemes is iff the URIs are lexicographically equal. Untrue. See below. > URIs themselves > express no other type of equivalence other than that since equivalence > is always application specific and more often than not is also context > specific. Unless you have some application specific knowledge talking > about equivalence of Resources is a very dangerous and, IMNSHO, simply > a Bad Thing To Do... Luckily, HTTP is an application protocol, so is in a very good position to define application specific knowledge/context, such as when http URIs are "equivalent" or not. Non-http URI schemes don't have that advantage. IMO, yet another reason why using http URIs is Goodness. MB
Received on Wednesday, 26 September 2001 12:01:41 UTC