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Subject: Re: contracted exceptions
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From: Ray Blaak <rAYblaaK@STRIPCAPStelus.net>
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Organization: The Transcend
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Date: Fri, 08 Jun 2007 17:40:37 GMT
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Date: 2007-06-08T17:40:37+00:00
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Robert A Duff <bobduff@shell01.TheWorld.com> writes:
> Ray Blaak <rAYblaaK@STRIPCAPStelus.net> writes:
> > or even worse:
> >
> >   try
> >   {
> >     doSomething();
> >   }
> >   catch (SomeError e)
> >   {
> >   }
> 
> Well, this part of the problem can't be blamed on the language.
> This code is just plain bad practise.  The solution is better
> training for programmers, not better language design

Well, you are right in theory. The problem is that such naive programmers are
directed by the compiler to do something about the exception, and being naive
they make this mistake. Training is hard, and this particular problem is
unexpectedly pervasive.

So, when one realizes that in the majority of cases all that is happening is
just an upwards perculation, that in fact the exception checking is not
usually needed, the observation is that changing the language design lets
quirkly irrational imperfect humans avoid certain errors more readily.

What we should strive for in language design are approaches that naturally
encourage correct or robust behaviour by default, so that the need for
training becomes less of an issue. 

> You should almost never silently swallow an exception
> like that, and if you do, you should always have a comment
> explaining why.

Absolutely.

-- 
Cheers,                                        The Rhythm is around me,
                                               The Rhythm has control.
Ray Blaak                                      The Rhythm is inside me,
rAYblaaK@STRIPCAPStelus.net                    The Rhythm has my soul.