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Date: Wed, 14 Aug 2013 12:23:41 -0200
To: Anthony Ferrara <ircmaxell@gmail.com>
CC: "internals@lists.php.net" <internals@lists.php.net>
Subject: Re: [PHP-DEV] [RFC] Constant Scalar Expressions
From: bobwei9@hotmail.com (Bob Weinand)

Am 13.08.2013 um 14:13 schrieb "Anthony Ferrara" <ircmaxell@gmail.com>:

> Hello all,
>=20
> I'd like to propose a new RFC for 5.NEXT:
>=20
> https://wiki.php.net/rfc/const_scalar_expressions
>=20
> This allows for defining constant expressions which are resolved at compil=
e
> time.
>=20
> for example:
>=20
> const FOO =3D 1 + 1;
> static $bar =3D 1 << 2;
> function foo($a =3D 1 | 2) {}
> class foo {
>    public $bar =3D 1 << 2;
> }
>=20
> Thoughts?
>=20
> Anthony

It really would be nice to use constants in these constant expressions.

I think this would be particulary useful when using bitwise operators. Examp=
le:

const FLAG_A =3D 1;
const FLAG_B =3D 2;
const FLAG_C =3D 4;

With this proposal we would write:
function func ($arg =3D 1 | 2 | 4) # we now need to lookup first which const=
ants have values 1, 2 and 4

But it would be much more understandable if we were able to write:
function func ($arg =3D FLAG_A | FLAG_B | FLAG_C)

Bob Weinand=