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Date: Sun, 10 Mar 2024 15:31:51 +0000
To: Larry Garfield <larry@garfieldtech.com>
Cc: php internals <internals@lists.php.net>
Subject: Re: [PHP-DEV] [RFC] [Discussion] Rounding Integers as int
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From: internals@gpb.moe ("Gina P. Banyard")

On Saturday, 9 March 2024 at 16:00, Larry Garfield <larry@garfieldtech.com>=
 wrote:

> I am still opposed to this. Logically, ceil/float/round should be returni=
ng ints, not floats. Only returning ints if it was given an int is, er, kin=
da pointless, as you'll just get back the value you passed in. (Because it'=
s already rounded/floored, etc.) So this doesn't get us any new type safety=
, but does make the return type less consistent than it is today. That's a =
step backwards.
>=20
> If there's some math reason that we cannot have those functions return in=
t (someone mentioned there was, but I don't really understand it and the RF=
C does not explain it at all), then we should at least keep consistency in =
the return type. "Sometimes I have to cast the return value before I can ac=
tually use it in the obvious way, sometimes I don't" is not a good situatio=
n.
>=20
> --Larry Garfield

There are plenty of values that are exactly representable as floating point=
 numbers but not as integers.

One short example:

$v =3D 1e10 + 0.6;
var_dump($v);
var_dump(round($v));

Gives you accurate precision and proper rounding behaviour.

1e10 *cannot* be represented as an integer.

So round *must* be able to return a float.

Best regards,

Gina P. Banyard