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From: Florian Weimer <fw@deneb.enyo.de>
Newsgroups: comp.lang.ada
Subject: Re: controlled type in generic package?
Date: 08 Feb 2001 17:56:59 +0100
Organization: Enyo's not your organization
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Date: 2001-02-08T17:56:59+01:00
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John English <je@bton.ac.uk> writes:

> Not only that, but by deriving something from Controlled, you're
> giving up your ability to derive from anything else. If I want to
> derive a new type from an existing (non-Controlled) type and add
> a destructor (Finalize), I have to perform lots of acrobatics and
> commit all sorts of atrocities on my code to do it!

It's just an ordinary mixin construction.  Of course, there some
syntactical overhead involved, but it's straightforward.