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: a07f3367d7,2f7ef46127892c41 X-Google-Attributes: gida07f3367d7,public,usenet X-Google-NewGroupId: yes X-Google-Language: ENGLISH,ASCII-7-bit Received: by 10.180.98.234 with SMTP id el10mr214560wib.3.1343097413867; Mon, 23 Jul 2012 19:36:53 -0700 (PDT) Path: q11ni52614391wiw.1!nntp.google.com!feed-C.news.volia.net!volia.net!news2.volia.net!feed-A.news.volia.net!npeer.de.kpn-eurorings.net!npeer-ng0.de.kpn-eurorings.net!xlned.com!feeder1.xlned.com!border2.nntp.ams.giganews.com!nntp.giganews.com!news.nobody.at!eternal-september.org!feeder.eternal-september.org!mx04.eternal-september.org!.POSTED!not-for-mail From: Simon Wright Newsgroups: comp.lang.ada Subject: Re: Little people supporting Ada, possibly through AdaCore? Date: Wed, 18 Jul 2012 18:49:22 +0100 Organization: A noiseless patient Spider Message-ID: References: <12955589.960.1336138013614.JavaMail.geo-discussion-forums@vbbfk16> <5043095.1117.1336142172111.JavaMail.geo-discussion-forums@vbli11> <2d7fae9a-5be7-4011-a945-5ecd95684025@googlegroups.com> <949570cd-bdda-49ff-93c7-5189546adf7a@googlegroups.com> <5004ff62$0$293$14726298@news.sunsite.dk> Mime-Version: 1.0 Injection-Info: mx04.eternal-september.org; posting-host="2b7ac4c347cd2e988a774c08b2f7df8d"; logging-data="22907"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX19n0wVwOtlYlvD1CqZdzOfshll8auRmLdw=" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.1 (darwin) Cancel-Lock: sha1:e+QDM3oEW+6BYqEEOea+JgRUgNo= sha1:0DZ3M/99y2GKmGh+vbOBgGMVvGs= Content-Type: text/plain Date: 2012-07-18T18:49:22+01:00 List-Id: "Dmitry A. Kazakov" writes: > On Wed, 18 Jul 2012 06:33:34 -0700 (PDT), Marc C wrote: > >> An "unordered" set is an *unordered* set. It is inappropriate to expect >> any kind of intrinsic or 'order of insertion' ordering of elements in >> such a set. > > True. However a set of truly unordered elements cannot be implemented > otherwise than on top of an ordered set. E.g. to be able to implement > membership test. Either the container imposes some order on the elements or > else the elements have some arbitrary order. > > It is interesting to speculate about the interface of an unordered set such > that the clients could not exploit its ad-hoc order. We had a requirement to display at most 50 log entries. We tried again and again (but no further) to ask what the sort criteria should be if there were more than 50 log entries; explaining that if we did nothing the users would see the first 50 entries in the hashed map. The result of that was a rant about the fact that the order depended on the component library and might change; the response to which was that we would never accept an upgraded component library without going through appropriate acceptance procedures. We never did find out what the sort criteria should be.