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From: Simon Wright <simon@pogner.demon.co.uk>
Subject: Re: "out" or "access"
Date: 1998/11/03
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Newsgroups: comp.lang.ada
Date: 1998-11-03T00:00:00+00:00
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Matthew Heaney <matthew_heaney@acm.org> writes:

> I'm designing a data structure library --which I've been calling the Ada
> Components Library-- which comprises pluggable units.  You assemble the
> data structure having the space & time characteristics you desire, from
> a simpler set of primitives.  (Sound like our favorite language?)
[..]
> From time-to-time, it's desirable to change the values of the items in
> the data structure, without resorting to inefficient "solutions" like
> copying the original data structure, and changing the source values
> prior to insertion into the target structure.  You just want to change
> the values in place.

Yes, I'm going through the same throes with the Booch Components at
the moment.

Having the ability to change components in place during iteration
causes a whole lot of grief, in the BCs showing up as

generic
  type Item is private;
  type Item_Ptr is access all Item;
package BC.Containers is

yecch