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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Subject: Re: GNAT packages in Linux distributions
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Date: Tue, 11 May 2010 18:45:14 +0200
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Date: 2010-05-11T18:45:12+02:00
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On Tue, 11 May 2010 18:05:42 +0200, Yannick Duch�ne (Hibou57) wrote:

> Le Tue, 11 May 2010 17:46:58 +0200, Pascal Obry <pascal@obry.net> a �crit:
> 
>> Le 11/05/2010 09:39, Dmitry A. Kazakov a �crit :
>>> I am not. Eiffel does it wrong. SPARK does it right.
>>
>> Eiffel and SPARK are completely different beasts, I do not see how you
>> can compare them.
>>
> Can be compared in their attempt to make proofs or to draw a path to it.  
> But Eiffel's concepts are mostly a kind of debugging or runtime exception  
> oriented, and you are right if you were to point that Eiffel is not to do  
> static inference.

Because it does not include exceptions in the contract, which is obviously
wrong.

> While they can be compared in some way, there is indeed a big difference :  
> Eiffel is runtime oriented, SPARK is static analysis oriented.

A proof of correctness cannot be run-time. Incorrectness need no proof.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de