Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!usenix!std-unix
From: karl@IMA.ISC.COM (Karl Heuer)
Newsgroups: comp.std.unix
Subject: ambiguous match with multiple-character collating elements
Keywords: international regexp/gmatch
Message-ID: <487@usenix.ORG>
Date: 5 Sep 90 22:20:45 GMT
Sender: std-unix@usenix.ORG
Reply-To: karl@IMA.ISC.COM (Karl Heuer)
Organization: Interactive Systems, Cambridge, MA 02138-5302
Lines: 15
Approved: jsq@usenix.org (Moderator, John Quarterman)
X-Submissions: std-unix@uunet.uu.net

From:  karl@IMA.ISC.COM (Karl Heuer)

In an environment where the digraph "ch" collates as a single element, what
happens if an attempt is made to match the subject string "chi" with the
pattern "[c[.ch.]]i" or "[c[.ch.]]hi"?  Is the implementation required to
report a successful match in both cases?  If so, it would seem necessary to
use a nondeterministic finite automaton or equivalent, thus making simple
regexp matching and filename globbing as complex as egrep pattern matching.

If you have an answer that's based on something other than your own intuition,
please specify which (draft) standard you're referencing.

Karl W. Z. Heuer (karl@kelp.ima.isc.com or ima!kelp!karl), The Walking Lint

Volume-Number: Volume 21, Number 82