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From: Florian Weimer <fw@deneb.enyo.de>
Newsgroups: comp.lang.ada
Subject: Re: Ada 2012 : aliased parameters ?
Date: Sat, 23 Apr 2011 20:47:16 +0200
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Date: 2011-04-23T20:47:16+02:00
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* Randy Brukardt:

> The motivating case is to make the containers better. Ada 2012 adds the 
> following to all of the containers:
>
>     function Reference (Container : aliased in out Vector; Position : in 
> Cursor)
>        return Reference_Type;
>
> where Reference_Type is defined as:
>
>     type Reference_Type (Element : not null access Element_Type) is private
>        with
>           Implicit_Dereference => Element;

Is it necessary that Element is a discriminant?  If the aliased
business works with fields, you could write something like this:

  type String_Reference is record
     Data : access String;
  end record;

  function "+" (S: aliased String) return String_Reference is
  begin
     return String_Reference'(Data => S'Access);
  end "+";

String_Reference could be part of an array, so we would get ragged
arrays as a side effect.

In any case, it seems to me that the definition of "master" in 7.6.1
needs updating.