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!aioe.org!5WHqCw2XxjHb2npjM9GYbw.user.gioia.aioe.org.POSTED!not-for-mail From: "Dmitry A. Kazakov" Newsgroups: comp.lang.ada Subject: Re: Simple example on interfaces Date: Tue, 26 Jan 2021 09:07:05 +0100 Organization: Aioe.org NNTP Server Message-ID: References: <9e1b5d67-be08-4f53-aadc-fbed761a8c24n@googlegroups.com> NNTP-Posting-Host: 5WHqCw2XxjHb2npjM9GYbw.user.gioia.aioe.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-Complaints-To: abuse@aioe.org User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.6.1 Content-Language: en-US X-Notice: Filtered by postfilter v. 0.9.2 Xref: reader02.eternal-september.org comp.lang.ada:61203 List-Id: On 2021-01-26 08:33, G.B. wrote: > Composition can be a good alternative, too. Composition was the starting point. See the original post. > It can help making the type graph modular. By modular by mean disconnected? But the question was to make it connected by removing duplicated nodes. > It naturally adds separation of concerns. > Is there good reason to prefer Is-A over Has-A? It is not a question of preference, it either fallacy (when set in mixed with a member of) or else different interfaces, like record type interface vs. some other interface. > If all the types are related through inheritance, > will refactoring become easier or harder? You meant reuse, probably. Composition was zero re-use beyond your editor's clipboard support of cut-and-paste. As for logical relationships between types, usually such things are influenced by the problem space. The question of design to map these by language types. -- Regards, Dmitry A. Kazakov http://www.dmitry-kazakov.de