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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Newsgroups: comp.lang.ada
Subject: Re: about the new Ada 2012 pre/post conditions
Date: Wed, 20 Jun 2012 23:04:17 +0200
Organization: cbb software GmbH
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Date: 2012-06-20T23:04:17+02:00
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On Wed, 20 Jun 2012 13:51:32 -0700 (PDT), Maciej Sobczak wrote:

> Decades of experience (OK, Java is a bit younger) show that it will usually be used as:
> 
> begin
>    Push (S, Element);
> exception
>    when others => null;
>    -- TODO: (errr, it never happens, right?)
> end;
> 
> The first version is at least easier to follow in the debugger...

Not in Ada where exceptions are not contracted. In Ada one just forgets to
catch.

Which raises an interesting question: if Ada had contracted exceptions,
people would start adding meaningless when others =>. But with contracted
exceptions the compiler would know all exceptions possible in the context.
We could make others an illegal choice in such cases. The programmer would
have to explicitly specify exceptions to catch.

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