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=-1.3 required=5.0 tests=BAYES_00,INVALID_MSGID autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: fac41,a48e5b99425d742a X-Google-Attributes: gidfac41,public X-Google-Thread: 1108a1,5da92b52f6784b63 X-Google-Attributes: gid1108a1,public X-Google-Thread: ffc1e,a48e5b99425d742a X-Google-Attributes: gidffc1e,public X-Google-Thread: f43e6,a48e5b99425d742a X-Google-Attributes: gidf43e6,public X-Google-Thread: 103376,a48e5b99425d742a X-Google-Attributes: gid103376,public From: Ken Garlington Subject: Re: Papers on the Ariane-5 crash and Design by Contract Date: 1997/03/24 Message-ID: <3336D280.5EA3@lmtas.lmco.com>#1/1 X-Deja-AN: 228004985 References: <332B5495.167EB0E7@eiffel.com> Organization: Lockheed Martin Tactical Aircraft Systems Newsgroups: comp.lang.eiffel,comp.object,comp.software-eng,comp.programming.threads,comp.lang.ada Date: 1997-03-24T00:00:00+00:00 List-Id: Jon S Anthony wrote: > > In article <33330FE5.3F54BC7E@eiffel.com> Bertrand Meyer writes: > > > > From this we learn that Java and Ada 95 are not properly designed for > > > Design by Contract. > > > > Which is the simple truth. The designers of these languages have > > explicitly rejected the inclusion of assertions. Why? They are the > > ones to ask. I am sure they must have their reasons (however > > unlikely it is I would find these to be good reasons). > > It is simply amazing to see you sit there (or type there) and say in > one breath "Which is the simple truth" and then proceed to make an > absolutely false statement in the next. In fact, it is extremely > disappointing and makes you look ridiculous. That's not fail. Mr. Meyer does, in the same post, define what he means by assertions, which is a superset of Ada's. Certainly, it contradicts any notion that the Design by Contract method is appropriate in any language - in fact, Mr. Meyer has explicitly stated that Eiffel is the only widespread language that supports Design by Contract. My problem with the paper is, again, two-fold: 1. The claim that Eiffel assertions would have prevented the Ariane V is clearly unsupported by the final report. 2. Claims that Design by Contract is not language-specific (i.e. Eiffel) are also clearly false, and attempts to sell it as such are silly. > > Ada _has_ assertions. Their form is not of the same syntactical look > as Eiffel's. So what? They take the form of constraints, in > particular (wrt to the case at hand) subtype constraints. They are > _not_ as flexible or full "featured" as Eiffel's but they are > certainly there and in the Ariane case, they are every bit as capable > as Eiffel's. There is no difference in this sort of case. You are > just plain a) wrong or b) - well it doesn't take a genius to fill in > the obvious answer to this option. > > > > It's bad enough that you post statements that are explicitly > > > contradicted by the Ariane V final report (e.g. that the IRS could not be > > > tested in a black-box environment). When you post statements that are > > > contradicted by your *own* paper... > > > > No evidence has been furnished of either of the purported > > contradictions. > > Do you have any idea how ridiculous this sort of statement makes you > look??? You are not doing Eiffel any favors here... > > /Jon > > -- > Jon Anthony > Organon Motives, Inc. > Belmont, MA 02178 > 617.484.3383 > jsa@organon.com -- LMTAS - The Fighter Enterprise - "Our Brand Means Quality" For job listings, other info: http://www.lmtas.com or http://www.lmco.com