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,c52c30d32b866eae X-Google-Attributes: gidfac41,public X-Google-Thread: 103376,2ea02452876a15e1 X-Google-Attributes: gid103376,public X-Google-Thread: 1108a1,c52c30d32b866eae X-Google-Attributes: gid1108a1,public From: bobduff@world.std.com (Robert A Duff) Subject: Re: Real OO Date: 1996/05/14 Message-ID: #1/1 X-Deja-AN: 154837229 references: organization: The World Public Access UNIX, Brookline, MA newsgroups: comp.lang.eiffel,comp.lang.ada,comp.object Date: 1996-05-14T00:00:00+00:00 List-Id: In article , Steve Tynor wrote: >In fact, such a precondition would be a violation of the VAPE validity >rule (section 9.8, ETL). Our compiler treats this as only a Warning >(since there are several PD libraries that use this construct), though >technically it should be an Error. OK, I just re-read 9.8, and I stand corrected. A post-condition can refer to things unknown to the client, but a pre-condition cannot. There is some discussion in 9.8 about why this difference makes sense, and it talks about how the "interface form" will not include post-conditions that have unknown meaning to the client. However, I find the definition of "Availability of an Assertion Clause" in that section confusing. Is it not the case that pre-conditions are always "available"? - Bob P.S. I find it appalling that your compiler is unable to enforce the rules of the language, because some code disobeys those rules. Is this because there exist some compilers that don't bother to enforce the rules?! Yuck. This is a common problem with C, but I thought Eiffel was above that problem.