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=-1.9 required=5.0 tests=BAYES_00,FREEMAIL_FROM autolearn=unavailable autolearn_force=no version=3.4.4 X-Received: by 10.42.249.207 with SMTP id ml15mr14879049icb.21.1400711622663; Wed, 21 May 2014 15:33:42 -0700 (PDT) X-Received: by 10.50.6.103 with SMTP id z7mr375783igz.11.1400711622590; Wed, 21 May 2014 15:33:42 -0700 (PDT) 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!usenet.blueworldhosting.com!feeder01.blueworldhosting.com!news.glorb.com!c1no13205684igq.0!news-out.google.com!qf4ni5721igc.0!nntp.google.com!c1no13205681igq.0!postnews.google.com!glegroupsg2000goo.googlegroups.com!not-for-mail Newsgroups: comp.lang.ada Date: Wed, 21 May 2014 15:33:42 -0700 (PDT) In-Reply-To: Complaints-To: groups-abuse@google.com Injection-Info: glegroupsg2000goo.googlegroups.com; posting-host=66.126.103.122; posting-account=KSa2aQoAAACOxnC0usBJYX8NE3x3a1Xq NNTP-Posting-Host: 66.126.103.122 References: User-Agent: G2/1.0 MIME-Version: 1.0 Message-ID: <06f66a19-00f1-405f-a517-05d18a021b65@googlegroups.com> Subject: Re: Suggestion: Allow functions returning abstract types in certain situations From: Adam Beneschan Injection-Date: Wed, 21 May 2014 22:33:42 +0000 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Xref: news.eternal-september.org comp.lang.ada:19964 Date: 2014-05-21T15:33:42-07:00 List-Id: On Wednesday, May 21, 2014 3:04:05 PM UTC-7, Robert A Duff wrote: > Adam Beneschan writes: > >...In my view, the language model depends heavily on > > the assumption that an object can never be created whose tag refers to > > an abstract type; allowing the rule to *ever* be relaxed could be > > disastrous. >=20 > I don't think so. As I posted a while back, the only trouble comes > from converting an object of an abstract type to a class-wide > type -- that is what needs to be forbidden. Hmmm... I'd worry that if we allowed an object with an abstract-type tag to= exist even for a little while, something in the language semantics might r= equire Initialize, Adjust, or Finalize to be called on it, which could be b= ad if, for example, it tried to redispatch to an abstract body. (I don't r= emember the earlier conversation, so I don't know if this was dealt with al= ready.) -- Adam