Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!cs.utexas.edu!asuvax!ukma!psuvax1!news From: flee@cs.psu.edu (Felix Lee) Newsgroups: news.software.b Subject: Re: Problems with expire in CNews Message-ID: Date: 26 Apr 91 03:41:56 GMT References: <1991Apr24.180649.14798@zoo.toronto.edu> <1991Apr25.001832.19898@s1.msi.umn.edu> Sender: news@cs.psu.edu (Usenet) Organization: ~/News/org Lines: 26 Nntp-Posting-Host: dictionopolis.cs.psu.edu >I have no idea how hard it would be to make the ordering of the lines >non-important, but it sure would be nice. It's a matter of using a different "best match" rule. C News expire currently uses "first match". Nearly every alternative is incompatible with this behavior. One alternative is "last match". This is possibly more natural than first match. I tend to want "all" near the top, since a general rule should appear before exceptions to the rule. Another rule is "earliest expire": pick the matching line that expires the article soonest. This rule makes it hard to say something like: news.announce x 30 - news x 5 - The opposite rule is "latest expire", which has the opposite problem. A good rule is "strongest match": X is a stronger match than Y if the set of X is a proper subset of the set of Y. This will probably do what everyone expects most of the time. Unfortunately, it isn't specific enough. What if you have: all.test x 3 - misc.all x 5 - How do you expire misc.test? You have to defer to another rule. -- Felix Lee flee@cs.psu.edu