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Subject: Re: [PHP-DEV] NAN and INF cast to int
From: lester@lsces.co.uk (Lester Caine)

Robert Stoll wrote:
>>> I'm +1 to make div by zero return INF.
>>
>> This begs the question 'how' ...
>> If we are processing to integer values they produce an integer result and there
>> is no provision for a 'number' INF. This is the exact sort of request that
>> prompted my recent article on 'what is a number' ...
>>
>
> PHP behaves already different. 1/2 = 0.5
> So it would be perfectly valid to define 2/0 = INF
>
> Personally, I would prefer to keep false for a division with two integers (e.g. 1/0) but would change the result as
> follows if a float is involved
> 1.0/0 = INF
> 1/0.0 = INF
> 0.0/0 = NAN
> 0/0.0 = NAN
> pretty much as other language behave (right?).

But that is not 'cast to int' ...
http://phpsurgery.org/wiki/integer is my take on some of this, and if you follow 
the results on stackoverflow asking why there is not a NAN or INF value for 
numbers in other languages you will see that your list only works for 'float' 
... but mapping everything to float is wrong?

The real problem here is what 'container' is created when calculating
int(x) / int(y) = ???
27/3 can give a clean int(9), but 27/2 has a remainder and 27/0 can't produce an 
int() result? Some other container needs to be created?

-- 
Lester Caine - G8HFL
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