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 10.224.169.1 with SMTP id w1mr17426848qay.4.1376147429901; Sat, 10 Aug 2013 08:10:29 -0700 (PDT) X-Received: by 10.49.11.134 with SMTP id q6mr483270qeb.0.1376147429888; Sat, 10 Aug 2013 08:10:29 -0700 (PDT) Path: border1.nntp.dca3.giganews.com!border3.nntp.dca.giganews.com!border1.nntp.dca.giganews.com!nntp.giganews.com!f7no1806646qan.0!news-out.google.com!he10ni1415qab.0!nntp.google.com!fx3no1895444qab.0!postnews.google.com!glegroupsg2000goo.googlegroups.com!not-for-mail Newsgroups: comp.lang.ada Date: Sat, 10 Aug 2013 08:10:29 -0700 (PDT) In-Reply-To: <6ee1653b-7232-4a32-940d-25bb556a19d4@googlegroups.com> Complaints-To: groups-abuse@google.com Injection-Info: glegroupsg2000goo.googlegroups.com; posting-host=69.20.190.126; posting-account=lJ3JNwoAAAAQfH3VV9vttJLkThaxtTfC NNTP-Posting-Host: 69.20.190.126 References: <19fr4wmxmen$.gjbias2fj461$.dlg@40tude.net> <72539e4c-dddd-40e4-82e8-14c4f2016ccc@googlegroups.com> <1656c260-4488-42d8-8d31-0fde538470ee@googlegroups.com> <6ee1653b-7232-4a32-940d-25bb556a19d4@googlegroups.com> User-Agent: G2/1.0 MIME-Version: 1.0 Message-ID: Subject: Re: GNAT GPL 2013 bug? From: Shark8 Injection-Date: Sat, 10 Aug 2013 15:10:29 +0000 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable X-Original-Bytes: 2712 Xref: number.nntp.dca.giganews.com comp.lang.ada:182941 Date: 2013-08-10T08:10:29-07:00 List-Id: On Friday, August 9, 2013 2:30:40 PM UTC-6, Adam Beneschan wrote: >=20 > It doesn't seem particularly useful to declare an untagged private type w= hose full type is something that only the package, or a child package, coul= d derive types from. I think I used this in one of my starts for a PostScript Interpreter. Posts= cript objects forming a hierarchy and all. So it could be useful if you are= implementing something which has a common set of properties in implementat= ion that are irrelevant to the actual client. > Unfortunately, Ada doesn't have the concept of a "tagged type from which = nothing can be derived". That concept would be useful so that one could de= clare a type derived from Ada.Finalization.Controlled or some other tagged = type, but declare that no other types may be derived from it, so that *new*= operations declared for the type wouldn't have to be dispatching. Good point; but on the flipside there's lots of workarounds for final objec= ts in Java. So a choice either way has problems. IMO.