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From: Cyrille <comar@eu.adacore.com>
Newsgroups: comp.lang.ada
Subject: Re: Preventing type extensions
Date: Fri, 24 Sep 2010 01:39:53 -0700 (PDT)
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Date: 2010-09-24T01:39:53-07:00
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On Sep 24, 10:16=A0am, "J-P. Rosen" <ro...@adalog.fr> wrote:
> and replace every redispatching call to M2 by a call to M2_Class, then
> the big case disappears. You need (of course) to check coverage for
> M2_Class, but M1 needs to be checked only for values of type T, not for
> descendants. That's what I meant when I said that coverage testing drops
> from N to 1

OK, I kind of supposed you had something like that in mind. Many years
ago, we proposed a similar idea in a few papers, See for instance
http://www.adacore.com/wp-content/uploads/2006/03/Certification_OO_Ada_Answ=
er.pdf.
Another one written by Franco G. is even mentioned in Chelinsky's FAA
study on OO (see http://www.tc.faa.gov/its/worldpac/techrpt/ar0717.pdf).
The study is worth reading by the way... We had more automatic
translation in mind at the time but the idea is the same.
doing this