- From: Mark Davis <mark.davis@icu-project.org>
- Date: Thu, 22 Sep 2005 08:13:18 -0700
- To: Arnt Gulbrandsen <arnt@gulbrandsen.priv.no>
- CC: Martin Duerst <duerst@it.aoyama.ac.jp>, Philip Guenther <guenther+collation@sendmail.com>, public-ietf-collation@w3.org
The goal and work so far is good. I'll need to read the document over more carefully, but one quick point. The specification should make very sure that some formal properties are observed. > Since ordering is normally used to sort a list of items, "error" is not a useful return value from the ordering function. Strings with errors that prevent the sorting algorithm from functioning correctly should sort to the end of the list. Thus if the first string is invalid while the second string is valid, the result will be "+1". If the second string is invalid while the first string is valid, the result will be "-1". If both strings are invalid, the result SHOULD match the result from the "i;octet" collation. This does not yet require that the order relation MUST be transitive, which is an absolute requirement. Similarly: Equality MUST be an equivalence relationship (reflexive, symmetric, and transitive). Ordering MUST establish a total order (that is, < is transitive and trichotomous), and must be consistent with the Equality relationship. Matching MUST be defined such that if there is a match, the substring meets the equality criteria. Note: there are some real gotchas in matching, see http://www.unicode.org/reports/tr10/#Searching Also, I haven't looked it over in detail on this point, but with reference to attributes, I'd point people to the CLDR specification for the kinds of things that are needed. http://unicode.org/cldr/data/docs/web/tr35.html#%3Ccollation%3E Mark Arnt Gulbrandsen wrote: > > Martin Duerst writes: > >> I think this is great! This is the best way to get the draft finally >> moving on at greater speed. I happen to know the chair, and I agree >> with your description of her abilities. >> >> On the other hand, I'm somewhat worried that the we may end up with a >> draft that's perfect for IMAP, but doesn't work for other >> protocols/formats/languages. > > > I'd be surprised. If you rephrase less strongly, then perhaps. Our needs > aren't THAT different. > >> Therefore, please make sure that all discussion is (cross)posted to >> the public-ietf-collation@w3.org list. This at least gives people from >> other venues a chance to comment; if they miss that chance, then >> that's their fault. > > > Will try. And at least I'll mention every change loudly and clearly. > > Arnt > > > >
Received on Thursday, 22 September 2005 15:13:27 UTC