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From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: GNAT GPL 2013 bug?
Date: Fri, 09 Aug 2013 22:35:19 +0100
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Date: 2013-08-09T22:35:19+01:00
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Adam Beneschan <adambeneschan@aol.com> writes:

> It doesn't seem particularly useful to declare an untagged private
> type whose full type is something that only the package, or a child
> package, could derive types from.

Ada.Containers manage to make derivation impractical quite well, by
having a large number of functions with controlling parameters! In fact,
I think containers in general are something you wouldn't really want to
derive from; and (in the case I fell over - I needed set-like properties
for vectors) I only needed 9 subprograms and cursors, so composition did
the trick.