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From: Robert Dewar <robert_dewar@my-deja.com>
Subject: Re: disjoint ranges ?
Date: 2000/10/16
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In article <wcc66ms91t9.fsf@world.std.com>,
  Robert A Duff <bobduff@world.std.com> wrote:

> For example, the approach I would take in this case would be
to add
> arbitrary boolean conditions as invariant conditions (somewhat
as in
> Eiffel), and then *get rid of* all the various kinds of
special-purpose
> constraints (range, index, discrim, accuracy).

But unless you have a secret solution to the halting problem,
you will be faced with considerable complexity of deciding
which of these conditions can be checked at compile time
(Indeed I think this could make 4.9 look like a picnic).

After all, you are the first to know that what looks simple
at first sight often turns out not to be.


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