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From: Florian Weimer <fw@deneb.enyo.de>
Newsgroups: comp.lang.ada
Subject: Re: Lazy Evaluation [Side-Effects in Functions]
Date: Wed, 07 Nov 2001 14:32:27 +0100
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dewar@gnat.com (Robert Dewar) writes:

>> Uh, unless you do something like
>>   Swap(A(I), I)
>> (where A is an array, of course)
>
> Well yes, we all know Algol-60! (or at least I hope any
> serious student of programming languages does). But there
> is no special problem here. In Algol-60, the effect will be canonical,
> depending on the exact order of statements in the body.

Even if you use two temporary variables instead of a single one (which
is more usual, but in this case, the implementation hardly reflects
the symmetry of the operation)?