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From: Maciej Sobczak <see.my.homepage@gmail.com>
Newsgroups: comp.lang.ada
Subject: Re: Inherited Methods and such
Date: Wed, 26 Sep 2007 14:37:09 -0700
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Date: 2007-09-26T14:37:09-07:00
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On 26 Wrz, 14:21, Robert A Duff <bobd...@shell01.TheWorld.com> wrote:

> Is this something fundamentally broken about constructors,
> or is just another case of uninitialized variables?
> I mean, there are lots of other ways to create uninit vars
> in Ada...

Yes, but for most of them it is easy to analyze the code and spot the
problem.
Most of them can be even found by the compiler itself, without
involving any human-driven code review.

Here the problem is in the interaction between base and derived type.
The important feature of OO is that implementations (bodies) for T and
S might not be available for review at the same time. If you look at T
in isolation, it's clean. If you look at S in isolation (and this is
the only thing you can do if you have only the interface ot T without
the implementation), it's clean as well.
Somehow together they don't work.

The problem with this example is that in general it's impossible to
analyze.

--
Maciej Sobczak
http://www.msobczak.com/