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From: Florian Weimer <fw@deneb.enyo.de>
Newsgroups: comp.lang.ada
Subject: Re: Preventing type extensions
Date: Sun, 12 Sep 2010 14:53:18 +0200
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	<874odv9npv.fsf@ludovic-brenta.org>
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Date: 2010-09-12T14:53:18+02:00
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* Ludovic Brenta:

> Florian Weimer writes on comp.lang.ada:
>> Suppose I've got a tagged type.  I want to expose the fact that it is
>> a tagged type outside its package, but want to prevent type extensons.
>> (In short, I'm interested in something like final classes in Java or
>> C++0X.)
>
> I think the way to do this is to hide the fact that the type is tagged
> :/ Why do you want to make the type publicly tagged if not to allow type
> extension?

I want to use some features which come with tagged types, like the OO
call notation or the fact that the type implements an interface.