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: f43e6,2c6139ce13be9980 X-Google-Attributes: gidf43e6,public X-Google-Thread: 103376,3d3f20d31be1c33a X-Google-Attributes: gid103376,public X-Google-Thread: 1108a1,2c6139ce13be9980 X-Google-Attributes: gid1108a1,public From: doylep@ecf.toronto.edu (Patrick Doyle) Subject: Re: Interface/Implementation (was Re: Design by Contract) Date: 1997/09/05 Message-ID: #1/1 X-Deja-AN: 270005352 X-Nntp-Posting-Host: skule.ecf Sender: news@ecf.toronto.edu (News Administrator) References: <340F20A0.49B5@ac3i.dseg.ti.com> <340F39E3.4B71@pseserv3.fw.hac.com> Organization: University of Toronto, Engineering Computing Facility Newsgroups: comp.object,comp.software-eng,comp.lang.ada,comp.lang.eiffel Date: 1997-09-05T00:00:00+00:00 List-Id: In article <340F39E3.4B71@pseserv3.fw.hac.com>, W. Wesley Groleau x4923 wrote: > >Hear, hear! Why would an Eiffel programmer want to simulate Ada, when >he/she could actually use Ada? (And vice versa, lest anyone think >I'm making another language-bigot comment...) > >The discussion of language merits is not served by either side >trying to avoid consideration of a difference by offering a kludgy >workaround of the other language's feature. Being the one who seems to be pursuing this quest, I'll explain myself. I'm not trying to emulate Ada. Creating an interface that can be frozen for programmers to work against is a very important thing. On first glance, it seems there's no easy way to do that in Eiffel, besides using the Short tool and checking the output for changes. My point is that deferred classes *are* interfaces, so if you want to freeze an interface, freeze a deferred class. See--it has little to do with Ada. I'm simply referring to Ada because it has a built-in facility for creating interfaces for every class, and so the Ada people have a great deal of experience with this methodology; so I was asking them about using deferred classes because presumably they'd be the best ones to find the flaws in the deferred class methodology. -PD -- -- Patrick Doyle doylep@ecf.utoronto.ca