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From: "Randy Brukardt" <randy@rrsoftware.com>
Newsgroups: comp.lang.ada
Subject: Re: Ada 2012 Constraints (WRT an Ada IR)
Date: Wed, 14 Dec 2016 16:53:11 -0600
Organization: JSA Research & Innovation
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Xref: news.eternal-september.org comp.lang.ada:32836
Date: 2016-12-14T16:53:11-06:00
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"Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> wrote in message 
news:o2r1ca$184u$1@gioia.aioe.org...
...
> Others tried to argue that such bodies are not bodies but magically 
> "preconditions". No, they are still bodies, just misplaced ones.

Body /= implementation!! (Using "implementation" here in your sense as the 
entire execution of a subprogram.) A body is just the hidden part of the 
implementation; the part that is exposed to callers includes constraint, 
null exclusion, and predicate checks, and the precondition. The caller has a 
need to know about part of the implementation, and hopefully not about the 
rest. Exactly where the split between the specification and the body goes 
clearly depends on a need to know basis, and it has nothing to do with 
whether it is static or dynamic or provable.

                           Randy.