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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Subject: Re: and then... (a curiosity)
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Date: Tue, 2 Sep 2008 18:48:14 +0200
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Date: 2008-09-02T18:48:14+02:00
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On Tue, 2 Sep 2008 15:32:40 +0200, stefan-lucks@see-the.signature wrote:

> A short-circuit "and" (instead of "and then") would not remove that choice 
> -- see the "much better style" above. 

Disagree.

I think a far better idea would be to introduce pure functions and
procedures with results. Functions with side effects and access parameters
is an insanity.

It is also worth to consider introduction of commutative, associative,
inverse operations per contract. This would allow the compiler to prevent a
procedure with the result from appearing in a commutative "and". The
evaluation order of non-associative etc operations could be fixed.

Later it would also allow to manage a combinatory explosion variants in
multi-methods ("and", "or", "+", "*" etc).

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