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From: "Jeffrey R. Carter" <spam.jrcarter.not@spam.not.acm.org>
Newsgroups: comp.lang.ada
Subject: Re: Preventing private procedure visibility being made public through
 extension
Date: Sun, 21 May 2017 23:09:57 +0200
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Date: 2017-05-21T23:09:57+02:00
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On 05/21/2017 10:21 PM, Jere wrote:
>
> I just don't
> like using access types if I can avoid them.

Of course you can avoid them.

> So something like:
>
>    type My_Type is tagged limited private;
>    function Get_Libaray_Component
>       (Obj : in out My_Type)
>       return not null access Library_Type;
> private
>    type My_Type is new Other_Library_Type with record
>       Base : aliased Library_Type;
>    end record;

There are a finite number of operations defined for Library_Type, and, as you 
said, a smaller number that make sense for your abstraction. So you simply 
define equivalent operations for My_Type that call the appropriate operations 
for Library_Type with the Base component. No access types, simple, safe, and clear.

-- 
Jeff Carter
"I soiled my armor, I was so scared."
Monty Python & the Holy Grail
71