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From: Victor Porton <porton@narod.ru>
Newsgroups: comp.lang.ada
Subject: Re: Controlled types as interfaces
Date: Wed, 20 Aug 2014 15:50:58 +0300
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Date: 2014-08-20T15:50:58+03:00
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Dmitry A. Kazakov wrote:

>> A similar thing can be made with Root_Stream_Type making it derived from
>> Root_Stream_Interface interface.
> 
> Yes, of course. It was proposed multiple times, as I remember. But
> rejected as "not backward compatible." Though the compatibility issue was
> quite minor if any.

We can make Root_Stream_Type a descendant of Root_Stream_Interface.

So old code can derive from Root_Stream_Type and this is backward 
compatible.

-- 
Victor Porton - http://portonvictor.org