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From: "G.B." <bauhaus@notmyhomepage.invalid>
Newsgroups: comp.lang.ada
Subject: Re: Example Ada calling Gnu Scientific Library (GSL)
Date: Fri, 31 Mar 2017 20:31:15 +0200
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Date: 2017-03-31T20:31:15+02:00
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On 30.03.17 16:22, Dmitry A. Kazakov wrote:
> Preconditions may help, do we have formal generic pre-/post-conditions?

As a hint to a user of generic package, it seems
possible to announce aspects of FP Types required:

generic
    type Fractional is digits <>;
package R is
    type T is new Fractional
    with
      Dynamic_Predicate => (Fractional'Digits >= 8
                              and T in -4.0 .. +4.0);
    
    function Algo (X : T) return T;
end R;