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From: Maciej Sobczak <see.my.homepage@gmail.com>
Newsgroups: comp.lang.ada
Subject: Re: Ada 2012 : aliased parameters ?
Date: Tue, 29 Mar 2011 00:34:49 -0700 (PDT)
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On 29 Mar, 05:16, "Randy Brukardt" <ra...@rrsoftware.com> wrote:

> The motivating case is to make the containers better. Ada 2012 adds the
> following to all of the containers:
>
> =A0 =A0 function Reference (Container : aliased in out Vector; Position :=
 in
> Cursor)
> =A0 =A0 =A0 =A0return Reference_Type;

Out of curiosity - is it possible to leak the reference this way? I
mean - is it possible for the caller to make a copy of returned
reference and store it arbitrarily long?

Note that the "copy" might not be obvious, as in:

declare
   My_Element : Vector_Type.Reference_Type renames
     My_Vector.Reference (My_Cursor);
begin
   My_Element.Comp :=3D 10;
   My_Element.Other_Comp :=3D 3.14;
end;

The C++ equivalent of this is both a fantastic performance feature and
a deadly security hole. How is this solved in Ada?

--
Maciej Sobczak * http://www.msobczak.com * http://www.inspirel.com