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From: Robert A Duff <bobduff@shell01.TheWorld.com>
Newsgroups: comp.lang.ada
Subject: Re: Garbage Collection ???
Date: Sat, 14 Apr 2012 14:21:17 -0400
Organization: The World Public Access UNIX, Brookline, MA
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Date: 2012-04-14T14:21:17-04:00
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"ldries46" <bertus.dries@planet.nl> writes:

> I would declare these variables as not null access whatever, ...

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;

Or in GNAT, "Predicate =>" instead of "Dynamic_Predicate =>".

- Bob