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From: "Randy Brukardt" <randy@rrsoftware.com>
Newsgroups: comp.lang.ada
Subject: Re: We should introduce aliased types
Date: Fri, 1 Aug 2014 14:49:13 -0500
Organization: Jacob Sparre Andersen Research & Innovation
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Date: 2014-08-01T14:49:13-05:00
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"Randy Brukardt" <randy@rrsoftware.com> wrote in message 
news:lrgqnq$4i3$1@loke.gir.dk...
> "Victor Porton" <porton@narod.ru> wrote in message
...
> And you can't directly declare a component as
>    Ptr : access T := T'Access;
> because of accessibility; the problem isn't whether T is aliased or not. 
> "access T" is a library-level type, while T'Access might refer to a local 
> object, so the access type could outlive the object (in particular, this 
> component could be copied into an object of another library-level type), 
> and that's not allowed.

Actually, you can do that so long as you use Unchecked_Access:

      type T is limited record
          Ptr : access T := T'Unchecked_Access;
      end record;

                                 Randy.