Re: S'Is_nan or S'Is_inf?

["Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>]

On Fri, 16 Jul 2010 17:06:38 +0000 (UTC), Warren wrote:

> Dmitry A. Kazakov expounded in news:1tbp3geoa5yna$.171cmlfdrbm98$.dlg@
> 40tude.net:
> 
>> with Ada.Text_IO;  use Ada.Text_IO;
>> procedure IEEE is -- Only if Float is IEEE!
>>    Zero : Float := 0.0;
>>    Inf  : Float := 1.0 / Zero;
>>    NaN  : Float := 0.0 / Zero;
>> begin
>>    Put_Line ("Valid    " & Boolean'Image (Inf'Valid));
>>    Put_Line ("In range " & Boolean'Image (Inf <= Float'Last));
>>    Put_Line ("Self NaN " & Boolean'Image (NaN = NaN));
>> end IEEE;
>> 
>> On an IEEE machine it could print 3x FALSE.
> 
> On a non IEEE machine, is there going to be an exception 
> raised when dividing by zero?

I would say yes. But theoretically if a non-IEEE machine has special
representations of x/0, as IEEE does, then the compiler vendor is permitted
not to raise Constraint_Error.

Language lawyers?

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de