From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham autolearn_force=no version=3.4.4 X-Google-Thread: 103376,9b7d3a51d0d8b6ee X-Google-Attributes: gid103376,domainid0,public,usenet X-Google-Language: ENGLISH,ASCII-7-bit Path: g2news2.google.com!postnews.google.com!r37g2000prr.googlegroups.com!not-for-mail From: Adam Beneschan Newsgroups: comp.lang.ada Subject: Re: Extending discriminant types Date: Wed, 26 Nov 2008 07:49:42 -0800 (PST) Organization: http://groups.google.com Message-ID: <50d6e1ae-a312-4c77-9fda-6ded331b5ddb@r37g2000prr.googlegroups.com> References: <20081115101632.5f98c596@cube.tz.axivion.com> <8e021577-260a-44e1-b765-4d81f6ba89df@33g2000yqm.googlegroups.com> <492be08b$0$32676$9b4e6d93@newsspool2.arcor-online.net> <0xZWk.396391$TT4.276049@attbi_s22> <71304b75-71bc-4691-b511-69882bdc0fc3@a12g2000pro.googlegroups.com> <492c77a1$0$31347$9b4e6d93@newsspool4.arcor-online.net> <2ebc6a98-ebd9-4bfb-b69a-c313e9a9090a@w39g2000prb.googlegroups.com> <2T1Xk.451865$yE1.273979@attbi_s21> <20081126103846.3f9475ac@cube.tz.axivion.com> <163e7b10-8571-4320-ad80-39c522e474d3@j35g2000yqh.googlegroups.com> <20081126111646.6d064e36@cube.tz.axivion.com> NNTP-Posting-Host: 66.126.103.122 Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Trace: posting.google.com 1227714582 28834 127.0.0.1 (26 Nov 2008 15:49:42 GMT) X-Complaints-To: groups-abuse@google.com NNTP-Posting-Date: Wed, 26 Nov 2008 15:49:42 +0000 (UTC) Complaints-To: groups-abuse@google.com Injection-Info: r37g2000prr.googlegroups.com; posting-host=66.126.103.122; posting-account=duW0ogkAAABjRdnxgLGXDfna0Gc6XqmQ User-Agent: G2/1.0 X-HTTP-UserAgent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.7.12) Gecko/20050922 Fedora/1.7.12-1.3.1,gzip(gfe),gzip(gfe) Xref: g2news2.google.com comp.lang.ada:3783 Date: 2008-11-26T07:49:42-08:00 List-Id: On Nov 26, 3:05 am, Ludovic Brenta wrote: > anon's theorem: the number of bugs in a program decreases with time > and eventually reaches zero, whether or not anyone maintains the > program. (However, to observe this theorem, someone must use the > program.) > > I'd be interested in anon's proof of that theorem. That would > definitely make it into the Jargon file :) I'm not sure that it could be proven mathematically, but perhaps it could be tested. In particular, we could test whether this theory or the contrary theory is true, the contrary theory being one that you posted earlier in this thread: ## Even an infinite amount of testing cannot prove a program to be bug- ## free; it can only uncover an infinite amount of bugs. While this may not be literally true---I suspect it is mathematically impossible for a finite compiler to have an infinite number of bugs--- it could be reformulated in a way that makes it amenable to testing. My proposal, then, is that if anon can't prove his theory formally, we should ask him to do it empirically by performing an infinite amount of testing on GNAT, and then coming back to comp.lang.ada and reporting on the results once this testing process is complete. -- Adam