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From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: Wikibook on Ada Programming - Object Orientation
Date: Thu, 08 Jul 2010 18:14:45 +0100
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Ludovic Brenta <ludovic@ludovic-brenta.org> writes:

> Right, I'm curious. I re-read sections on controlled types and mixin
> inheritance in John Barnes' book but he leaves this entire problem as
> an exercise to the reader (specifically, exercise 19.3).  This seems
> too complicated for a beginner.

I've checked the answers, John was solving a simpler problem (to keep
track of how many instances of a type have been created, and to give
each a unique ID). Although he says that "[having] a component of a
controlled type [...] will give the effect of controlling objects of
[the containing type]" this won't result in the ability to fully support
initialize/adjust/finalize.