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From: Paul Rubin <no.email@nospam.invalid>
Newsgroups: comp.lang.ada
Subject: Re: How to get Ada to "cross the chasm"?
Date: Thu, 26 Apr 2018 00:57:05 -0700
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Date: 2018-04-26T00:57:05-07:00
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Simon Wright <simon@pushface.org> writes:
> I tried proving a quicksort and failed dismally

Verifying a sorting algorithm is traditionally a tough challenge for a
proof system.  You have to prove that the output is a permutation of the
input, that it is sorted, and that the algorithm terminates.  Each of
those can be a bit messy, depending.  It is doable, but you might start
out with something easier.