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From: Robert A Duff <bobduff@world.std.com>
Subject: Re: Modular types inside records
Date: 2000/10/23
Message-ID: <wccd7gr385o.fsf@world.std.com>#1/1
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Sender: bobduff@world.std.com (Robert A Duff)
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Organization: The World Public Access UNIX, Brookline, MA
Newsgroups: comp.lang.ada
Date: 2000-10-23T00:00:00+00:00
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niewiap@widzew.net (Pawe� Niewiadomski) writes:

> Pretty neat, huh?  Not as flexible as my previous (erroneous) idea (you 
> need to instantiate the generic every time you want to change the size of 
> your queue), but still gets rid of constraint verification problem.  It is 
> just a rough, untested idea, but I think it will work.

It can be made to work.

But I don't think this is a good use of modular types.  Instead, use a
normal (signed) integer type ("range 0..Whatever"), and use an explicit
"mod" operation, or an explicit if statement.  That makes the code more
readable, by making it clear what's going on at the "wraparound" place.

- Bob