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Date: Tue, 15 Jul 2014 13:11:34 +0100
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To: bishop@php.net
Subject: Re: [PHP-DEV] [RFC] intdiv()
From: ajf@ajf.me (Andrea Faulds)


On 15 Jul 2014, at 03:31, Bishop Bettini <bishop@php.net> wrote:
> I need some education.  Can you elaborate on the specific situations =
where integer division would be used without other functions from bcmath =
or gmp?
>=20
> I see in the RFC you mention seconds to hh:mm and index to rows/cols, =
but can you give some actual "before" and "after" samples?  Like this is =
how it would be done today without intdiv, and here's how it would be =
done after?

Sure. Say I have a number of seconds which I wish to split into years, =
days, hours, minutes and seconds, for example:

$s =3D 1000000;
$seconds =3D $s % 60;
$minutes =3D intdiv($s, 60) % 60;
$hours =3D intdiv($s, 3600) % 24;
$days =3D intdiv($s, 3600 * 24) % 365;
$years =3D intdiv($s, 3600 * 24 * 365);

Currently, you=92d have to cheat and use floating-point division:

$x =3D 1000000;
$seconds =3D $s % 60;
$minutes =3D (int)($s / 60) % 60;
$hours =3D (int)($s / 3600) % 24;
$days =3D (int)($s / (3600 * 24)) % 365;
$years =3D (int)($s / (3600 * 24 * 365));

The second one is a bit of a hack, really, but it would probably work =
most of the time since realistically nobody is using >53-bit time values =
at the moment (though people are using >32-bit values, so that 64-bit =
RFC can=92t come soon enough given Y2K38).

However, intdiv() is perhaps not the best way to implement it or the =
best syntax.

--
Andrea Faulds
http://ajf.me/