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From: "Robert I. Eachus" <rieachus@comcast.net>
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Subject: Re: += in ada
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Wes Groleau wrote:

> which agress with Robert E. -- it's
> implementation dependent.
> 
> A simple (though not 100% equivalent)
> alternative is
> 
>   if Integer'Last / X <= Y
> 
> (not 100% because if the product just equals
> Integer'Last it will be rejected, but if
> I used "<" integer division could let a few
> overflow values squeak through.

Ah, but if Integer'Last is prime, then that is not an issue.  So on a 32 
bit machine your code would be fine.  The problem you describe can occur 
if Integer'Last is 2**15 - 1, 2**35 - 1, or 2**63 - 1. ;-)

-- 
                                                     Robert I. Eachus

"Quality is the Buddha. Quality is scientific reality. Quality is the 
goal of Art. It remains to work these concepts into a practical, 
down-to-earth context, and for this there is nothing more practical or 
down-to-earth than what I have been talking about all along...the repair 
of an old motorcycle."  -- from Zen and the Art of Motorcycle 
Maintenance by Robert Pirsig