Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:71017
Mailing-List: contact internals-help@lists.php.net; run by ezmlm
Received-SPF: pass (pb1.pair.com: domain tutteli.ch designates 80.74.154.78 as permitted sender)
To: "'Lester Caine'" <lester@lsces.co.uk>,
	"'PHP internals'" <internals@lists.php.net>
References: <001801cf07e9$a07af1e0$e170d5a0$@tutteli.ch> <52C5B5E1.5050609@lerdorf.com> <003c01cf07ee$123e08e0$36ba1aa0$@tutteli.ch> <52C5BE84.1050904@ajf.me> <CAMUwpuSohoJHi3sNEQ8d0eTd=BHgD+VJ5paC0t2HmY=z15O-hQ@mail.gmail.com> <52CABAA2.8090805@lsces.co.uk>
In-Reply-To: <52CABAA2.8090805@lsces.co.uk>
Date: Mon, 6 Jan 2014 15:23:27 +0100
Message-ID: <001001cf0aea$dfab1530$9f013f90$@tutteli.ch>
MIME-Version: 1.0
Content-Type: text/plain;
	charset="us-ascii"
Content-Transfer-Encoding: 7bit
Thread-Index: AQJ/fRdWvDY7Kzfg/9Kc358Lr8TUtwHAAYsWAdUtbC4Ay/10KwMgJGQJAWiw+NKYz4mYEA==
Content-Language: de-ch
Subject: RE: [PHP-DEV] NAN and INF cast to int
From: php@tutteli.ch ("Robert Stoll")


> -----Original Message-----
> From: Lester Caine [mailto:lester@lsces.co.uk]
> Sent: Monday, January 06, 2014 3:16 PM
> To: PHP internals
> Subject: Re: [PHP-DEV] NAN and INF cast to int
> 
> Julien Pauli 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?). 

> The bottom line is that 'int' simply does not have any means of returning NAN or
> INF so why are you even discussing it? It is messages relating to an 'int'
> object that need handling? Divide when divisor is '0' is a state that needs
> handling by the code, what ever the type of number object.
> 
> As Rasmus has indicated, how a platform handles these edge cases is the
> inconsistent bit that needs documenting, and this is another aspect I need to
> add to my notes ...
> 
> --
> Lester Caine - G8HFL
> -----------------------------
> Contact - http://lsces.co.uk/wiki/?page=contact
> L.S.Caine Electronic Services - http://lsces.co.uk
> EnquirySolve - http://enquirysolve.com/
> Model Engineers Digital Workshop - http://medw.co.uk
> Rainbow Digital Media - http://rainbowdigitalmedia.co.uk
> 
> --
> PHP Internals - PHP Runtime Development Mailing List
> To unsubscribe, visit: http://www.php.net/unsub.php