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-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,c42dbf68f5320193 X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2002-05-09 20:38:03 PST Path: archiver1.google.com!news1.google.com!newsfeed.stanford.edu!logbridge.uoregon.edu!sunqbc.risq.qc.ca!newspeer.monmouth.com!newscon02.news.prodigy.com!newsmst01.news.prodigy.com!prodigy.com!postmaster.news.prodigy.com!newssvr14.news.prodigy.com.POSTED!3bae8248!not-for-mail From: tmoran@acm.org Newsgroups: comp.lang.ada Subject: Re: Generation of permutations References: <5ee5b646.0205091548.cd99d4c@posting.google.com> X-Newsreader: Tom's custom newsreader Message-ID: NNTP-Posting-Host: 67.112.202.37 X-Complaints-To: abuse@prodigy.net X-Trace: newssvr14.news.prodigy.com 1021001841 ST000 67.112.202.37 (Thu, 09 May 2002 23:37:21 EDT) NNTP-Posting-Date: Thu, 09 May 2002 23:37:21 EDT Organization: Prodigy Internet http://www.prodigy.com X-UserInfo1: [[PAPDONAJUMB_LY@BCBNWX@RJ_XPDLMN@GZ_GYO^RR@ETUCCNSKQFCY@TXDX_WHSVB]ZEJLSNY\^J[CUVSA_QLFC^RQHUPH[P[NRWCCMLSNPOD_ESALHUK@TDFUZHBLJ\XGKL^NXA\EVHSP[D_C^B_^JCX^W]CHBAX]POG@SSAZQ\LE[DCNMUPG_VSC@VJM Date: Fri, 10 May 2002 03:37:21 GMT Xref: archiver1.google.com comp.lang.ada:23817 Date: 2002-05-10T03:37:21+00:00 List-Id: > > but to determine whether a set of instructions > > So the set of instructions emitted by Gnat when it > >sort is indeed a general sorting algorithm. We can't for > >a moment assume that Tom *really* thinks that it is undecidable :-) > > So the only reading of Tom's message is an attempt to > disprove what I wrote by example. Another reading is that Tom foolishly left off the smiley when he tried to point out that things must be stated more carefully, and in particular, "a" set of instructions is different from "any" set of instructions, and if "a" had really been meant, then the statement would imply, for instance, that when "a set of instructions" happened to be the particular "set of instructions emitted by Gnat...", the sort couldn't be proved to work. Tom assumed that reader's of the message would not assume someone was ignorant of, or attempting to disprove by example, undecidability. Tom assumed wrong. ("Know your audience" & "Don't leave off smileys")**100