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From: Robert A Duff <bobduff@shell01.TheWorld.com>
Newsgroups: comp.lang.ada
Subject: Re: How many Ada compiler bugs are here?
Date: Fri, 13 Jan 2012 21:41:58 -0500
Organization: The World Public Access UNIX, Brookline, MA
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Date: 2012-01-13T21:41:58-05:00
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Adam Beneschan <adam@irvine.com> writes:

> I think that most likely, if I had a package P that declared a type
> like this, it would also declare some function (or a deferred
> constant) to represent some sort of "empty" or "null" or "undefined"
> value.

Have you read "The Billion Dollar Mistake", by C.A.R. Hoare?

- Bob