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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Newsgroups: comp.lang.ada
Subject: Re: derived formal types and known discriminants
Date: Fri, 30 Jun 2017 09:24:43 +0200
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Date: 2017-06-30T09:24:43+02:00
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On 30/06/2017 03:10, Randy Brukardt wrote:

> Surely, but no real loss. Using discriminants with tagged types is pretty
> rare in itself.

Access discriminants are needed to work around lack of constructors and 
full multiple inheritance. That is when one object refers to its 
separate part via an access discriminant.

Value discriminants are needed for having components of unconstrained types.

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