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From: Robert A Duff <bobduff@shell01.TheWorld.com>
Newsgroups: comp.lang.ada
Subject: Re: Normalizing array indices
Date: Wed, 02 Nov 2011 08:14:00 -0400
Organization: The World Public Access UNIX, Brookline, MA
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Date: 2011-11-02T08:14:00-04:00
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Simon Wright <simon@pushface.org> writes:

> I've had more surprises with
>
>    type Arr is array (Integer range <>) of Float;
>    A : Arr := (1.0, 2.0, 3.0);
>
> where A'First is Integer'First (on GNAT), ie -2**31.

Yes.  It's usually a bad idea to declare an unconstrained array
(T range <>) where T'First = T'Base'First, because then empty
arrays don't work well.

E.g., "array (Enum_Type) ..." is OK, but "array (Enum_Type range <>) ..."
is probably wrong.

- Bob