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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Newsgroups: comp.lang.ada
Subject: Re: discontinuous subtype without aspect
Date: Tue, 30 Jan 2018 19:15:33 +0100
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Date: 2018-01-30T19:15:33+01:00
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On 2018-01-30 18:31, Mehdi Saada wrote:
>> ...because people didn't want set constraints. I still fail to understand
> why, as you point out, a static predicate is not quite a replacement.

An arbitrary constraint does not preserve any properties of the type. 
The only meaning of a constraint is to create an algebraic structure of 
certain, provable or known properties. E.g. ranges keep the set of 
values convex etc. Without properties advertised to the clients it is 
just ad-hockery.

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