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From: stefan-lucks@see-the.signature
Newsgroups: comp.lang.ada
Subject: Re: and then... (a curiosity)
Date: Wed, 3 Sep 2008 15:22:01 +0200
Organization: Bauhaus-Universitaet Weimar
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> > and it is regrettable that Ada needs a more complex syntax for this.
> > (Well, "A and B" also implies "if B is false, don't care about A",
> > but in a programming language you can't have it both ways.)
> 
> Ah, but you can! That's what speculative execution gives you. Ada
> allows for that, under user control. In C, you must use nested 'if' to
> achieve control.

AFAIK, you cannot write "if (A>0) and (B/A<100) then ..." and then trust 
that no constraint_error is raised if A=0 in Ada. 

On the other hand, im Mathematics, such expressions are quite usual. 

-- 
------ Stefan Lucks   --  Bauhaus-University Weimar  --   Germany  ------
               Stefan dot Lucks at uni minus weimar dot de
------  I  love  the  taste  of  Cryptanalysis  in  the  morning!  ------