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: fac41,2c6139ce13be9980 X-Google-Attributes: gidfac41,public X-Google-Thread: 103376,3d3f20d31be1c33a X-Google-Attributes: gid103376,public X-Google-Thread: 1108a1,2c6139ce13be9980 X-Google-Attributes: gid1108a1,public X-Google-Thread: f43e6,2c6139ce13be9980 X-Google-Attributes: gidf43e6,public From: rodemann@mathematik.uni-ulm.de (Joerg Rodemann) Subject: Re: Interface/Implementation (was Re: Design by Contract) Date: 1997/09/10 Message-ID: <34167245.0@news.uni-ulm.de>#1/1 X-Deja-AN: 271243634 References: Followup-To: comp.object,comp.software-eng,comp.lang.ada,comp.lang.eiffel Organization: University of Ulm, SAI, Germany Newsgroups: comp.object,comp.software-eng,comp.lang.ada,comp.lang.eiffel Date: 1997-09-10T00:00:00+00:00 List-Id: Patrick Doyle (doylep@ecf.toronto.edu) wrote: > Ok. I'll go for that, because my argument all along has been that > abstract superclasses can do as much as *and more than* Ada specs. > So let's consider just the export aspects of an abstract class. Is > there anything that they can't do which Ada specs can do? How do you prevent that the implemented class derived from an abstract specification class can add public methods to those mentioned in that abstract class? Using Ada we have just two possibilities for add-ons: 1.) Create a child package and thus gain full access to the internals of a class. 2.) Create a new package and derive a new class from the former one or define classwide methods. All you can do now are overriding existing operations and use the methods exported by the former package. Also do not forget that Ada packages often contain more than one class declaration. By the way: I would like to hear from anyone who uses ClearCase along with Eiffel, too. Or is the usual development environment already multi-user, multi-platform capable? Yours Joerg -- rodemann@mathematik.uni-ulm.de | Dipl.-Phys. Joerg S. Rodemann Phone: ++49-(0)711-5090670 | Flurstrasse 21, D-70372 Stuttgart, Germany -------------------------------+--------------------------------------------- rodemann@rus.uni-stuttgart.de | University of Stuttgart, Computing Center Phone: ++49-(0)711-685-5815 | Visualization Department, Office: 0.304 Fax: ++49-(0)711-678-7626 | Allmandring 30a, D-70550 Stuttgart, Germany