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From: Robert A Duff <bobduff@shell01.TheWorld.com>
Newsgroups: comp.lang.ada
Subject: Re: Vector of Vectors.
Date: Sat, 17 Jan 2009 11:45:25 -0500
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"Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> writes:

> And the next step is
>
>    for Element in Vector loop
>       -- place "new procedure" here!
>    end loop;

Sather has an elegant iterator feature, which is along these lines.

> There is nothing better for iteration than loops.

Maybe things like "map" found in functional languages?

>...Downward closures are
> meant for different stuff.

I'd say your above "for..." syntax should be thought of as syntactic
sugar defined in terms of downward closures.  Or perhaps in terms
of some coroutine-like concept.

- Bob