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=-0.3 required=5.0 tests=BAYES_00, REPLYTO_WITHOUT_TO_CC autolearn=no autolearn_force=no version=3.4.4 Path: eternal-september.org!reader01.eternal-september.org!reader02.eternal-september.org!news.eternal-september.org!news.eternal-september.org!news.eternal-september.org!feeder.eternal-september.org!aioe.org!.POSTED!not-for-mail From: "Dmitry A. Kazakov" Newsgroups: comp.lang.ada Subject: Re: Generics vs. O-O? Date: Fri, 2 Aug 2013 19:51:03 +0200 Organization: cbb software GmbH Message-ID: <16kwiwxqxuhu4$.y37yztzjskfv$.dlg@40tude.net> References: <6238c325-79c5-4537-ba55-2800110dc6df@googlegroups.com> <1wugpqyea6s39$.e2e8eshup5wn$.dlg@40tude.net> <51fadf40$0$6557$9b4e6d93@newsspool4.arcor-online.net> <15qso6tlt3uf1.h45wqc019b00$.dlg@40tude.net> <51fb80d8$0$6561$9b4e6d93@newsspool4.arcor-online.net> <1so729qnkrrj2.ztrxvmlw6cb7.dlg@40tude.net> <8bef1dc4-547b-478e-b81a-09077212f821@googlegroups.com> Reply-To: mailbox@dmitry-kazakov.de NNTP-Posting-Host: q/ev1P9zCVSwu+vpMGX5Tw.user.speranza.aioe.org Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Complaints-To: abuse@aioe.org User-Agent: 40tude_Dialog/2.0.15.1 X-Notice: Filtered by postfilter v. 0.8.2 Xref: news.eternal-september.org comp.lang.ada:16662 Date: 2013-08-02T19:51:03+02:00 List-Id: On Fri, 2 Aug 2013 08:36:14 -0700 (PDT), Alan Jump wrote: > After all, what's a singleton? Singleton is a type of which only one instance exists. > By definition, to be a singleton > pattern, two criteria must be met: one and only one instance with a global > point of access, and initialization on first use. Singleton pattern is a method to enforce a type to be singleton in a language that does not provide this capacity. Reasons to deploy this pattern in Ada are questionable at best. Ada offers support of singletons where appropriate. Here is the list, maybe incomplete: 1. Anonymous arrays are singletons 2. Procedures and functions are singletons 3. Protected objects are singletons 4. Tasks objects are singletons -- Regards, Dmitry A. Kazakov http://www.dmitry-kazakov.de