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,fceb4e36ba4d570f X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2001-04-24 06:53:11 PST Path: newsfeed.google.com!newsfeed.stanford.edu!paloalto-snf1.gtei.net!news.gtei.net!enews.sgi.com!newshub2.rdc1.sfba.home.com!news.home.com!news1.rdc1.sfba.home.com.POSTED!not-for-mail Message-ID: <3AE585AD.FA264B4C@home.com> From: Robert Palasek Organization: @Home Network X-Mailer: Mozilla 4.61 [en]C-AtHome0407 (WinNT; U) X-Accept-Language: en MIME-Version: 1.0 Newsgroups: comp.lang.ada Subject: Re: ada95 and uml References: <3AE3A5BD.C0601A95@home.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Date: Tue, 24 Apr 2001 13:53:10 GMT NNTP-Posting-Host: 24.15.222.230 X-Complaints-To: abuse@home.net X-Trace: news1.rdc1.sfba.home.com 988120390 24.15.222.230 (Tue, 24 Apr 2001 06:53:10 PDT) NNTP-Posting-Date: Tue, 24 Apr 2001 06:53:10 PDT Xref: newsfeed.google.com comp.lang.ada:6885 Date: 2001-04-24T13:53:10+00:00 List-Id: bobpalasek wrote: > > But I don't understand the idea that you are supposed to be able to > > generate one from the other. That seems wrong and misguided to me. > > > > A model is an abstraction that carries some proper subset of > > salient points of the thing being modeled. For it to be useful, the > > model has to leave other stuff out. If it doesn't leave anything > > out, it's just an alternate representation. > Simon writes: > True; model + translation rules -> code. This is possible provided > your model is expressed with the precision required by the translation > rules[1]. What Simon writes is true of any formal rewriting system. As stated, it maybe too general to be useful. Let us suppose, however, that in this context "model" is limited to UML, and "code" stands for Ada. In this hypothetical situation, it should be possible to go from the model to an executable, and not very many people at all need to be concerned with the intermediate representation. Assembly language or machine code is fine. No need to bother anyone with Ada. Keep it simple. But my conceit misses the point of using modeling as an abstraction to help understand the problem and/or the solution. The model is deliberately more simple than the final design and implementation. That is the nature of modeling. To require the model to carry all the details seems misguided, sophomoric, to me.