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Date: Tue, 11 Nov 2025 11:50:21 +0000 (GMT)
To: Mikhail Savin <mikhail.d.savin@gmail.com>
cc: Valentin Udaltsov <udaltsov.valentin@gmail.com>, 
    php internals <internals@lists.php.net>
Subject: Re: [PHP-DEV] [RFC] [Discussion] Add values() Method to BackedEnum
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From: derick@php.net (Derick Rethans)

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On Tue, 11 Nov 2025, Mikhail Savin wrote:

> The RFC addresses this by adding "public static function values(): array"
> to the BackedEnum interface itself.
> With that in place, an enum that defines an incompatible values() will fa=
il
> at compile time with a normal method-signature incompatibility, exactly
> like it would for from()/tryFrom().
>=20
> Here=E2=80=99s a .phpt demonstrating the intended behavior:
>=20
> --TEST--
> Backed enums: user-defined values() incompatible with interface signature
> --FILE--
> <?php
>=20
> enum E: string {
>     case A =3D 'a';
>=20
>     // Intentional incompatibility: interface requires array return type
>     public static function values(): string {
>         return 'values';
>     }
> }
>=20
> ?>
> --EXPECTF--
> Fatal error: Declaration of E::values(): string must be compatible with
> BackedEnum::values(): array in %s on line %d

Right now, enums can have a "values()" function that can return anything=20
I desire: an array of enum cases, or objects created from these, or=20
strings, or M_PI.

If it has to be compatible with

=09`BackedEnum::values(): array(int|string)`

(which is what your contract demands, even though it can't express the=20
int|string part)

Then that is a BC break again.

cheers,
Derick
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