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From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: simple question on long_float/short_float
Date: Sat, 02 Oct 2010 21:09:26 +0100
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"Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> writes:

> I doubt it much. IEEE 754 is a normal floating-point + some
> non-numbers like NaN. As the name suggests, numeric computations are
> performed on *numbers*. IEEE 754 non-numbers might be useful for the
> languages with no means to deal with numeric errors. But in Ada you
> don't need that because Ada has numeric exceptions.

But GNAT doesn't raise numeric exceptions for floating-point
computations resuting in Inf or NaN ('Machine_Overflows is False).

You can use 'Valid, or you can define the range as Dmitry noted above
(range Float'Range, I think) in which case you get Constraint_Error on
overflow.