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From: "Martin Dowie" <martin.dowie@btopenworld.com>
Newsgroups: comp.lang.ada
Subject: Re: Mneson announcement and help request
Date: Wed, 2 Jun 2004 19:46:12 +0000 (UTC)
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Date: 2004-06-02T19:46:12+00:00
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"Marius Amado Alves" <amado.alves@netcabo.pt> wrote in message
news:mailman.37.1086198453.391.comp.lang.ada@ada-france.org...
> Ok, so the secret formula is:
>
>    cost(exception check) < cost(condition check) < cost(raising)

Quite possibly

"much <" cost(raising)

There might even be times when

    cost(exception check) = cost(condition check)

or


    cost(exception check) > cost(condition check)

> And of course which idiom is best for algorithm A depends on the nature
> and casuistics of A. Finding the critical algorithms and determining
> these properties for each one is the hard work now.

Absolutely but for some systems it might just be worth doing (particularly
hard real-time systems).

> In the ASCLWG discussion I didn't intend to demonstrate past the case at
> hand then, namely the first two costs above. Maybe I was blissfully
> ignorant of the third.
>
> Now I'll have one more hint next time I find some Mneson function slow.
>
> Thanks for the byte :-)

Your welcome! :-)

Cheers

-- Martin