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 fail
> at compile time with a normal method-signature incompatibility, exactly
> like it would for from()/tryFrom().
>
> Here’s a .phpt demonstrating the intended behavior:
>
> --TEST--
> Backed enums: user-defined values() incompatible with interface signature
> --FILE--
> <?php
>
> enum E: string {
> case A = 'a';
>
> // Intentional incompatibility: interface requires array return type
> public static function values(): string {
> return 'values';
> }
> }
>
> ?>
> --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
I desire: an array of enum cases, or objects created from these, or
strings, or M_PI.
If it has to be compatible with
`BackedEnum::values(): array(int|string)`
(which is what your contract demands, even though it can't express the
int|string part)
Then that is a BC break again.
cheers,
Derick
