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From: "Matthew Heaney" <mheaney@on2.com>
Newsgroups: comp.lang.ada
Subject: Re: Concatenation and Characters
Date: Thu, 24 Oct 2002 10:04:25 -0400
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Date: 2002-10-24T10:04:25-04:00
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"Grein, Christoph" <christoph.grein@eurocopter.com> wrote in message
news:mailman.1035439204.28367.comp.lang.ada@ada.eu.org...
> > Many Ada83 programmers made the same mistake: assuming that there's an
> > automatic check when indexing an array.  There was not, in Ada83.  There
is
> > now, in Ada95.
>
> RM83 4.1.1(4)
> ... The exception CONSTRAINT_ERROR is raised if an index value does not
belong
> to the range of the corresponding index of the prefixing array ...
>
>
> A: array (Some_Range) of Something;
>
> I: Some_Range;
> J: Integer;
>
> A (I) - the range check can be omitted

And there you see the problem.  If index I is initialized with garbage, then
program execution is errnoneous as soon as you use I to index into the
array.  If you're lucky you'll get a core dump.