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,f66d11aeda114c52 X-Google-Attributes: gidfac41,public X-Google-Thread: 103376,f66d11aeda114c52 X-Google-Attributes: gid103376,public From: jsa@alexandria.organon.com (Jon S Anthony) Subject: Re: Design By Contract Date: 1997/09/03 Message-ID: #1/1 X-Deja-AN: 269789462 References: Distribution: world Organization: PSINet Newsgroups: comp.lang.ada,comp.lang.eiffel Date: 1997-09-03T00:00:00+00:00 List-Id: In article nospam@thanks.com.au (Don Harrison) writes: > System validity, in its broadest sense, means that all usage of entities Well, you can define it anyway you wish, I suppose, but I was simply refering to its "traditional" usage vis-a-vis Eiffel. > While Eiffel currently fails WRT polymorphic usage, Ada fails WRT other > usage. See Deja News for details. > > So, your claim that Ada doesn't have system validity problems is false. As I recall, that scenario required the _concious_ and _explicit_ choice to violate certain aspects via Unchecked_Conversion. Not at all the same as the concealed land mines of Eiffel. But, I'm not going to say these are somehow ultra-bad or something. In practice they are probably not that big of a deal if you are aware and careful to avoid the situations. Besides, you snipped the one of two smileys I had in there... /Jon -- Jon Anthony OMI, Belmont, MA 02178, 617.484.3383 "Nightmares - Ha! The way my life's been going lately, Who'd notice?" -- Londo Mollari