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=-0.3 required=5.0 tests=BAYES_00, REPLYTO_WITHOUT_TO_CC autolearn=no autolearn_force=no version=3.4.4 X-Google-Thread: 103376,ea5071f634c2ea8b X-Google-NewGroupId: yes X-Google-Attributes: gida07f3367d7,domainid0,public,usenet X-Google-Language: ENGLISH,ASCII-7-bit Received: by 10.68.39.100 with SMTP id o4mr4312873pbk.0.1322055069186; Wed, 23 Nov 2011 05:31:09 -0800 (PST) Path: lh20ni9142pbb.0!nntp.google.com!news1.google.com!goblin2!goblin.stu.neva.ru!aioe.org!.POSTED!not-for-mail From: "Dmitry A. Kazakov" Newsgroups: comp.lang.ada Subject: Re: Generic-Package Elaboration Question / Possible GNAT Bug. Date: Wed, 23 Nov 2011 14:30:52 +0100 Organization: cbb software GmbH Message-ID: <14p8llstxrtci$.18hb93fkpteuv$.dlg@40tude.net> References: <7bf9bc32-850a-40c6-9ae2-5254fe220533@f29g2000yqa.googlegroups.com> <4295dc09-43de-4557-a095-fc108359f27f@y42g2000yqh.googlegroups.com> <3snehoqgs8ia$.1nobjem6g6hx6$.dlg@40tude.net> <128rdz2581345$.c4td19l7qp9z$.dlg@40tude.net> <16ipwvpdavifr$.17bxf7if7f6kh$.dlg@40tude.net> <4ecb78b1$0$6643$9b4e6d93@newsspool2.arcor-online.net> <1iofgbqznsviu$.phvidtvxlyj4$.dlg@40tude.net> <4ecbb96e$0$6581$9b4e6d93@newsspool3.arcor-online.net> <4ecbdfdb$0$6629$9b4e6d93@newsspool2.arcor-online.net> <12hfiflyf7pr5$.l3pkpgoid8xt$.dlg@40tude.net> <4ecc35b8$0$7628$9b4e6d93@newsspool1.arcor-online.net> <4eccd5d2$0$6637$9b4e6d93@newsspool2.arcor-online.net> Reply-To: mailbox@dmitry-kazakov.de NNTP-Posting-Host: FbOMkhMtVLVmu7IwBnt1tw.user.speranza.aioe.org Mime-Version: 1.0 X-Complaints-To: abuse@aioe.org User-Agent: 40tude_Dialog/2.0.15.1 X-Notice: Filtered by postfilter v. 0.8.2 Xref: news1.google.com comp.lang.ada:19084 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Date: 2011-11-23T14:30:52+01:00 List-Id: On Wed, 23 Nov 2011 12:15:30 +0100, Georg Bauhaus wrote: > On 23.11.11 10:04, Dmitry A. Kazakov wrote: >> On Wed, 23 Nov 2011 00:52:23 +0100, Georg Bauhaus wrote: >> >>> On 22.11.11 20:15, Dmitry A. Kazakov wrote: >>> >>>>> Meyer: "Programming is a human activity". >>>>> Programmers are led towards a solution during the process of programming. >>>>> Depending on the characteristics of the process, then, >>>>> programmers will produce different results. >>>> >>>> I see no word "debugging" there. >>> >>> A debugging aid is a means of finding mistakes when developing programs. >> >> So it is the debugging driven design you are advocating for. Designing by >> fixing bugs. Nice, very nice... exactly the thing I don't want for Ada. > > Specifications have bugs. That is irrelevant to the discussion about designing programs. If you want to switch to designing specifications then what do run-time assertions have to do with that? >> I bet that coffee is far more helpful than frantic patching the >> program in the debugger. > > What debugger? A tool for debugging. >> One of the key points of good design is NOT to have such descriptions. The >> reader of the program, be it human or the compiler should be able to >> *understand* what you are describing. > > What is it that a reader of a package spec should be able to understand? The package specification, I suppose. > ADTs without invariants? Invariant is an implementation detail which has nothing to do with the specification. Different implementation will have different invariants, evidently. > Subprograms of unknown effect, You confuse interface and implementation. >>> There is no right or wrong in most programs. >> >> You cannot build safe software on false premises. > > Almost all programs have a number of things that can go wrong, Program code cannot GO wrong, it IS either wrong or not, here and now. -- Regards, Dmitry A. Kazakov http://www.dmitry-kazakov.de