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 X-Google-Thread: 103376,7b207d193114a9 X-Google-Attributes: gid103376,public,usenet X-Google-Language: ENGLISH,ASCII-7-bit Path: g2news1.google.com!news1.google.com!eweka.nl!lightspeed.eweka.nl!195.114.231.69.MISMATCH!feeder.news-service.com!border1.nntp.ams.giganews.com!nntp.giganews.com!feeder1.cambrium.nl!feed.tweaknews.nl!news.netcologne.de!newsfeed-hp2.netcologne.de!newsfeed.arcor.de!newsspool1.arcor-online.net!news.arcor.de.POSTED!not-for-mail From: "Dmitry A. Kazakov" Subject: Re: Partial type specifications and their ordering Newsgroups: comp.lang.ada User-Agent: 40tude_Dialog/2.0.15.1 MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Reply-To: mailbox@dmitry-kazakov.de Organization: cbb software GmbH References: Date: Tue, 18 Mar 2008 09:40:54 +0100 Message-ID: <4yntq9j6q827.kusbb0olb916.dlg@40tude.net> NNTP-Posting-Date: 18 Mar 2008 09:40:53 CET NNTP-Posting-Host: 2ab81c4c.newsspool2.arcor-online.net X-Trace: DXC=ON9ABB8fPdLWDmlTRbh@=IA9EHlD;3YcB4Fo<]lROoRAFl8W>\BH3YB?lZb4T29SDMDNcfSJ;bb[EFCTGGVUmh?DLK[5LiR>kgBj`HMe4k3oDI X-Complaints-To: usenet-abuse@arcor.de Xref: g2news1.google.com comp.lang.ada:20461 Date: 2008-03-18T09:40:53+01:00 List-Id: On Mon, 17 Mar 2008 16:14:42 -0700 (PDT), Eric Hughes wrote: > My comment earlier today got my mind in a buzz on the topic of partial > types, so as a form of personal exorcism I wrote a skeleton draft. [...] Your draft does not explain why certain sets of types (called partial here) cannot form a proper class. My guess is that any set of types can be associated with a class. The procedure is a follows. You construct the intersection of the interfaces of the types from the set. (The set is countable infinite, so it should be possible to do) The result is the interface of the root. The relation "S derived from T" is obviously preserved on the class. Consequently, generic types (not Ada term, but the meaning is obvious) are fully equivalent to classes. The only difference is that the former do not have T'Class and thus lack corresponding polymorphic values (class-wides). IMO the difference is not in the semantics. -- Regards, Dmitry A. Kazakov http://www.dmitry-kazakov.de