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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Newsgroups: comp.lang.ada
Subject: Re: Generic-Package Elaboration Question / Possible GNAT Bug.
Date: Tue, 22 Nov 2011 15:32:44 +0100
Organization: cbb software GmbH
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Date: 2011-11-22T15:32:44+01:00
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On Tue, 22 Nov 2011 11:25:59 +0100, Georg Bauhaus wrote:

> On 22.11.11 09:29, Dmitry A. Kazakov wrote:
>>  I think that a solution is not in adding new sources of
>> exceptions, but by making exceptions contracted (using conditional
>> contracts, e.g. "I don't raise, if you don't", "I don't raise if there is N
>> units of memory free" etc).
> 
> I think that, with the exception of compiler-determines-all-of-this,
> the above is a well known characterization of DbC.

Not really. DbC is about upfront formalized requirements.

For contracted exceptions more important is how contracts influence the
implementation. The idea is that in order to be legal the program must be
written so that the contract would be provable. If not provable, either the
program or the contract has to be changed. That is opposite to dynamic
checks, you don't need to check for non-contracted exceptions.

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