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From: Robert A Duff <bobduff@shell01.TheWorld.com>
Newsgroups: comp.lang.ada
Subject: Re: Garbage Collection ???
Date: Thu, 19 Apr 2012 10:36:19 -0400
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Date: 2012-04-19T10:36:19-04:00
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Julian Leyh <julian@vgai.de> writes:

> Am Samstag, 14. April 2012 20:21:17 UTC+2 schrieb Robert A Duff:
>> In Ada 2012, you can say:
>> 
>>     type T_Ptr_Opt is access all T;
>>     subtype T_Ptr is T_Ptr_Opt with
>>         Dynamic_Predicate => T_Ptr /= null;
>
> In Ada 2005, you can already say:
>
>     type T_Ptr_Opt is access all T;
>     subtype T_Ptr is not null T_Ptr_Opt;

Right, but that's less useful, because it forces you
to initialize your variables (e.g. record components)
before you're ready to.

- Bob