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From: Bob Duff <bobduff@theworld.com>
Newsgroups: comp.lang.ada
Subject: Re: SPARK: missing case value
Date: Fri, 09 Oct 2015 10:53:49 -0400
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Date: 2015-10-09T10:53:49-04:00
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Mark Lorenzen <mark.lorenzen@gmail.com> writes:

> I think it is logical and correct. How would a compiler be able to determine
> the range of E if your precondition was more complex?

Well, the fact that compilers cannot prove ALL truthful things (see
halting problem ;-)) doesn't mean they shouldn't be required to prove
some simple things.

- Bob