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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Subject: Re: Copying rows in a two dimensional array.
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Date: Mon, 1 Feb 2010 09:37:57 +0100
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Date: 2010-02-01T09:37:57+01:00
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On Sun, 31 Jan 2010 21:11:12 -0500, Peter C. Chapin wrote:

> So I thought, "Perhaps A needs to be an array of arrays."
> 
> type Matrix is array(Positive range <>) of WHAT_EXACTLY?
> 
> Apparently the component type of an array needs to be fully constrained (which
> again makes sense)

Not really. Arrays should have been allowed to have discriminants. That was
missed in the language design. If they had discriminants you could write:

type Row is array (Positive range <>) of Float;
type Matrix (Width : Positive) is
   array (Positive range <>) of Row (1..Width);

(Of course  the array bounds should have been discriminants rather than
attributes)

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de