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From: Jacob Sparre Andersen <jacob@jacob-sparre.dk>
Newsgroups: comp.lang.ada
Subject: Re: Ada 2012 Constraints (WRT an Ada IR)
Date: Sat, 10 Dec 2016 16:24:07 +0100
Organization: JSA Research & Innovation
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Xref: news.eternal-september.org comp.lang.ada:32710
Date: 2016-12-10T16:24:07+01:00
List-Id: <comp.lang.ada>

Randy Brukardt wrote:

> procedure Delete (Container : in out Map;
>                   Position  : in out Cursor)
>     with Pre => (if not Has_Element (Position) then raise Constraint_Error);
>
> Here, instead of using an English comment to define this behavior, we've 
> used an Ada precondition. So what's undefined about this? It's exactly the 
> same semantics, and indeed my hope is that we update the RM to do this for 
> all of the container routines in Ada 202x.

Good plan!

Jacob
-- 
"Problems worthy of attack
 prove their worth by hitting back" -- Piet Hein