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 10.236.119.67 with SMTP id m43mr7446578yhh.31.1413131265890;
        Sun, 12 Oct 2014 09:27:45 -0700 (PDT)
X-Received: by 10.140.21.51 with SMTP id 48mr1634qgk.12.1413131265846; Sun, 12
 Oct 2014 09:27:45 -0700 (PDT)
Path: 
 eternal-september.org!reader01.eternal-september.org!reader02.eternal-september.org!news.eternal-september.org!mx02.eternal-september.org!news.eternal-september.org!feeder.eternal-september.org!usenet.blueworldhosting.com!feeder01.blueworldhosting.com!peer03.iad.highwinds-media.com!news.highwinds-media.com!feed-me.highwinds-media.com!dc16no2340081qab.1!news-out.google.com!i10ni83qaf.0!nntp.google.com!s7no2221630qap.0!postnews.google.com!glegroupsg2000goo.googlegroups.com!not-for-mail
Newsgroups: comp.lang.ada
Date: Sun, 12 Oct 2014 09:27:45 -0700 (PDT)
In-Reply-To: <aa0678d5-f777-4a52-952f-dc9a2f16ed74@googlegroups.com>
Complaints-To: groups-abuse@google.com
Injection-Info: glegroupsg2000goo.googlegroups.com; posting-host=91.55.206.34;
 posting-account=rmHyLAoAAADSQmMWJF0a_815Fdd96RDf
NNTP-Posting-Host: 91.55.206.34
References: <8d6fe2a6-a8fa-441f-8b35-fc5a744359fb@googlegroups.com>
 <m19muc$551$1@loke.gir.dk>
 <aa0678d5-f777-4a52-952f-dc9a2f16ed74@googlegroups.com>
User-Agent: G2/1.0
MIME-Version: 1.0
Message-ID: <64f0b8de-72d7-49d8-ac03-725819b1057e@googlegroups.com>
Subject: Re: Type extension and discriminants
From: AdaMagica <christ-usch.grein@t-online.de>
Injection-Date: Sun, 12 Oct 2014 16:27:45 +0000
Content-Type: text/plain; charset=ISO-8859-1
X-Received-Bytes: 2065
X-Received-Body-CRC: 4168952663
Xref: news.eternal-september.org comp.lang.ada:22394
Date: 2014-10-12T09:27:45-07:00
List-Id: <comp.lang.ada>

On Saturday, October 11, 2014 7:45:56 PM UTC+2, sbelm...@gmail.com wrote:
> package A is
>    type T1 (<>) is tagged limited private;
>    function T1_Ctor return T1;
> private
>    type T1 (I_Ptr : access Integer) is tagged limited null record;
> end A;
> 
> package body A is
>    function T1_Ctor return T1 is
>    begin
>       return (I_Ptr => null);
>    end T1_Ctor;
> end A;
> 
> with A;
> package B is
>    type T2 (<>) is new A.T1 with private;

I guess the following function is implicitly declared here and must be overridden because it's abstract:
     function T1_Ctor return T2;

>    function T2_Ctor return T2;
> private
>   type T2 is new A.T1 with null record;
> end B;
>
> package body B is
>    function T2_Ctor return T2 is
>    begin
>       return T2'(A.T1_Ctor with null record);
>    end T2_Ctor;
> end B;