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Date: Thu, 21 Jan 2021 15:28:55 -0600
To: "php internals" <internals@lists.php.net>
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Subject: Re: [PHP-DEV] [RFC] Null Coalescing Assignment in Method Signature
From: larry@garfieldtech.com ("Larry Garfield")

On Thu, Jan 21, 2021, at 5:51 AM, Daniel Simkus wrote:
> Hello all,
>=20
> I am writing to see if anyone is interested in an RFC for ability to=20=

> automatically coalesce nullable method parameters with the supplied=20=

> default. It would look something like this:
>=20
> function foo(?array $bar ??=3D []) {
>=20
> This would result in $bar automatically converting to an array if null=
=20
> is passed, as opposed to either having to do a null check before the=20=

> function call and not passing parameter at all - or alternatively=20
> having to do something like:
>=20
> function foo(?array $bar =3D []) {
> =C2=A0=C2=A0 =C2=A0$bar ??=3D [];
>=20
>=20
> I don=E2=80=99t see this creating any BC incompatibilites and the ??=3D=
 syntax is=20
> something already in use in PHP since 7~
>=20
> I don=E2=80=99t have any experience with C, so would ideally love it s=
omeone=20
> could help with the development with this, or maybe point me in the=20=

> right direction.
>=20
> I would also require RFC Karma if people are interested in opening a=20=

> discussion about this (dansimkus)
>=20
> Thank you all for your time
>=20
> Regards,
> Daniel Simkus

I'm unclear why you'd allow null at all then.  If you want $bar to be op=
tional, and to be an empty array if not specified, then just do:

function foo(array $bar =3D []) { ... }

At that point, the only thing adding ?array does is allow you to explici=
tly pass null, presumably because it has some meaning to your function. =
 If you don't want that, don't allow it.

--Larry Garfield