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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Newsgroups: comp.lang.ada
Subject: Re: Mixing public and private member of a class. Dealing with what to
 hide and not
Date: Wed, 13 Feb 2019 21:05:30 +0100
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Date: 2019-02-13T21:05:30+01:00
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On 2019-02-13 18:40, Daniel Norber wrote:
> Sorry for my bad english.
> I'm having big troubles in how Ada deals mixing public and private member of a class.

Well, this one of sore spots in Ada where information hiding does not 
work well. Anyway, try this:

    type T is abstract tagged record -- This is a helper type, no
       Public : Integer;             -- instances of
    end record;
    type S is new T with private; -- This is the interface type
private
    type S is new T with record
       Secret : Integer;
    end record;

P.S. In many cases you do not expose members, only operations.

P.P.S. Discriminants can be misused as read-only members:

    type S (Public : Integer) is new T with private;
private
    type S (Public : Integer) is new T with record
       Secret : Integer;
    end record;

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de