From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.5-pre1 (2020-06-20) on ip-172-31-74-118.ec2.internal X-Spam-Level: X-Spam-Status: No, score=-1.9 required=3.0 tests=BAYES_00 autolearn=ham autolearn_force=no version=3.4.5-pre1 Path: eternal-september.org!reader02.eternal-september.org!.POSTED!not-for-mail From: "J-P. Rosen" Newsgroups: comp.lang.ada Subject: Re: Simple example on interfaces Date: Tue, 26 Jan 2021 10:37:12 +0100 Organization: Adalog Message-ID: References: <9e1b5d67-be08-4f53-aadc-fbed761a8c24n@googlegroups.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Tue, 26 Jan 2021 09:37:13 -0000 (UTC) Injection-Info: reader02.eternal-september.org; posting-host="24648e7c757fe953aaddab1349b2637e"; logging-data="31259"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1/Qs5U3CitTNc266DP39yVY" User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.6.1 Cancel-Lock: sha1:N0B4oZnlZ4CzbJxNuxf9hGW5+RE= In-Reply-To: Content-Language: fr Xref: reader02.eternal-september.org comp.lang.ada:61206 List-Id: Le 25/01/2021 à 23:06, Dmitry A. Kazakov a écrit : > Ada interface is a type that has interface and no implementation. [It is > a silly idea inherited from Java.] > To make it look a little less silly, think of it as a promise: a type that implements an interface promises to provide a certain number of operations. Then you can define algorithms that work on any type that fulfills the promises. To me, the big benefit of interfaces is that it is NOT inheritance; you say that your type provides some operations, without needing to classify it with an is-a relationship. (I can hear screamings of pure-OO people who will not agree with me ;-) ) -- J-P. Rosen Adalog 2 rue du Docteur Lombard, 92441 Issy-les-Moulineaux CEDEX Tel: +33 1 45 29 21 52, Fax: +33 1 45 29 25 00 http://www.adalog.fr