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From: =?utf-8?Q?Yannick_Duch=C3=AAne_=28Hibou57?= =?utf-8?Q?=29?=
 <yannick_duchene@yahoo.fr>
Newsgroups: comp.lang.ada
Subject: Re: SPARK Question
Date: Tue, 07 May 2013 08:59:27 +0200
Organization: Ada @ Home
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Date: 2013-05-07T08:59:27+02:00
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Le Wed, 01 May 2013 15:35:20 +0200, Phil Thornley  =

<phil.jpthornley@gmail.com> a =C3=A9crit:
> Assuming you are using the latest version of SPARK, the simplest way t=
o
> do this is to also include the proof function Vec_Length in the body,
> and give it a return annotation. So in the spec put:
>
>    --# function Vec_Length (The_Vector : in Basic_Vector)
>    --#   return Positive;
>
>    function Get_Value
>      (The_Vector : in Basic_Vector;
>       At_Position : in Positive)
>       return Basis_Type;
>    --# PRE At_Position in Array_Range'First .. Vec_Length(The_Vector);=

>

That's exactly the kind of thing I miss with Ada 2012's Pre/Post: abilit=
y  =

to define something for use in pre/post only, without injecting it in th=
e  =

real program. That's finally what the above do.

-- =

=E2=80=9CSyntactic sugar causes cancer of the semi-colons.=E2=80=9D [1]
=E2=80=9CStructured Programming supports the law of the excluded muddle.=
=E2=80=9D [1]
[1]: Epigrams on Programming =E2=80=94 Alan J. =E2=80=94 P. Yale Univers=
ity