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From: robert_dewar@my-dejanews.com
Subject: Re: should I be interested in ada?
Date: 1999/02/25
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Date: 1999-02-25T00:00:00+00:00
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In article <7b2j2u$drp$1@plug.news.pipex.net>,
  "Nick Roberts" <Nick.Roberts@dial.pipex.com> wrote:
> In the case of the Reorder procedure example I gave, a
> part of X could be reordered simply by passing a part of
> it into the call, e.g.:
>
>    Reorder(X(a..b),J);

This misses a central point. Slices in Ada can only be
applied to one dimensional arrays. This (very
understandable) restriction is a significant one in
the context of numerical codes dealing with multi-
dimensional arrays.

The reason for the restriction is of course that otherwise
strides are not known at compile time in many cases where
they are known now, and that is a worrisome inefficiency.
(this has been well studied in the context of Algol-68,
which as far as I know was the first main stream language
to allow general slicing).

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