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The implementation uses conditional registration - > the native method is only added when the enum doesn't already define > values(), ensuring ZERO backward compatibility breaks. > > Key points: > * Native values() added automatically to new enums > * Existing enums with custom values() continue working unchanged > * Trait-based implementations are respected > * Libraries can maintain their implementation for older PHP versions > * Solves boilerplate problem (3,860+ implementations, ~24k-44k real > usage) > > Common use cases: > * Database migrations: $table->enum('status', Status::values()) > * Form validation: in_array($input, Status::values()) > * API responses: ['allowed_values' =3D> Status::values()] > > =3D=3D Implementation =3D=3D > > Working implementation with conditional registration: > https://github.com/php/php-src/pull/20398 > > The engine checks if values() exists before registering the native versio= n: > - User-defined values() present? Use it. > - No user-defined values()? Add native implementation. > > =3D=3D No BC Breaks =3D=3D > > This approach ensures: > * Existing code works unchanged (no migration needed) > * Immediate benefit for new code (automatic values()) > * Gradual adoption possible (libraries can migrate at their pace) > > Trade-off: Makes values() the only overridable enum method (unlike > cases/from/tryFrom). The RFC documents this as a pragmatic choice - > solving real problems without forced migrations. > > =3D=3D Questions =3D=3D > > 1. Is the conditional approach technically sound? > 2. Is the API consistency trade-off acceptable given the zero BC breaks? > 3. Any concerns with the implementation approach? > 4. Should I implement some steps from "Future scope" of the rfc now? > > Discussion period: 2 weeks minimum before voting. > > Looking forward to your feedback! > > Best regards, > Savin Mikhail > Hi, Mikhail! Thank you for the RFC. Consider this code if this RFC is accepted: enum EnumWithUserDefinedValuesMethod: string { case X =3D 'x'; public static function values(): string { return 'values'; } } function getBackedEnumValues(BackedEnum $enum): array { return $enum::values(); } getBackedEnumValues(EnumWithUserDefinedValuesMethod::X); This code will suddenly break, because inside getBackedEnumValues I can safely assume that BackedEnum::values() returns an array, since it's a part of the interface contract. However, EnumWithUserDefinedValuesMethod breaks the Liskov Substitution Principle by defining a method with a non-compatible return type and gives a runtime error. What you've basically suggested is to ignore the LSP. This is not a good idea. -- Best regards, Valentin --000000000000594a96064343c11d Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
=D0=BF=D0=BD, 10 =D0=BD=D0=BE=D1=8F=D0=B1= . 2025=E2=80=AF=D0=B3. =D0=B2 08:44, Mikhail Savin <mikhail.d.savin@gmail.com>:
Hi internals,

I've created an RFC= to add a native values() method to BackedEnum:

https:/= /wiki.php.net/rfc/add_values_method_to_backed_enum

=3D=3D Summar= y =3D=3D

The RFC proposes adding BackedEnum::values() that returns a= n indexed array
of all backing values. The implementation uses conditio= nal registration -
the native method is only added when the enum doesn&= #39;t already define
values(), ensuring ZERO backward compatibility bre= aks.

Key points:
=C2=A0 * Native values() added automatically to = new enums
=C2=A0 * Existing enums with custom values() continue working = unchanged
=C2=A0 * Trait-based implementations are respected
=C2=A0 *= Libraries can maintain their implementation for older PHP versions
=C2= =A0 * Solves boilerplate problem (3,860+ implementations, ~24k-44k real usa= ge)

Common use cases:
=C2=A0 * Database migrations: $table->en= um('status', Status::values())
=C2=A0 * Form validation: in_arra= y($input, Status::values())
=C2=A0 * API responses: ['allowed_values= ' =3D> Status::values()]

=3D=3D Implementation =3D=3D

= Working implementation with conditional registration:
https://github.com/p= hp/php-src/pull/20398

The engine checks if values() exists befor= e registering the native version:
=C2=A0 - User-defined values() present= ? Use it.
=C2=A0 - No user-defined values()? Add native implementation.<= br>
=3D=3D No BC Breaks =3D=3D

This approach ensures:
=C2=A0 *= Existing code works unchanged (no migration needed)
=C2=A0 * Immediate = benefit for new code (automatic values())
=C2=A0 * Gradual adoption poss= ible (libraries can migrate at their pace)

Trade-off: Makes values()= the only overridable enum method (unlike
cases/from/tryFrom). The RFC = documents this as a pragmatic choice -
solving real problems without fo= rced migrations.

=3D=3D Questions =3D=3D

1. Is the conditiona= l approach technically sound?
2. Is the API consistency trade-off accept= able given the zero BC breaks?
3. Any concerns with the implementation a= pproach?
4. Should I implement some steps from "Future scope"= of the rfc now?=C2=A0

Discussion period: 2 weeks minimum before vot= ing.

Looking forward to your feedback!

Best regards,
Savin= Mikhail

Hi, Mikhail!
<= br>Thank you for the RFC.

Consider this code if th= is RFC is accepted:

enum EnumWithUserDefinedVa=
luesMethod: string
{    case X =3D 'x';

    public static function values(): string
    {
        return 'values'=
;;
    }
}

function=
 getBackedEnumValues(BackedEnum $enum): array
{=

    return $enum::values();
}

getBackedEnumValues(EnumWithUserDe=
finedValuesMethod::X);

This code will suddenly break, because inside= =C2=A0getBackedEnumValues I can safely assume that BackedEnum::values() ret= urns an array, since it's a part of the interface contract.

However,=C2=A0EnumWithUserDefinedValuesMetho= d breaks the Liskov Substitution Principle by defining a method with a non-= compatible return type and gives a runtime error.

What you've basically suggested is to ignore the LSP. = This is not a good idea.

--
Best regards, Valentin
--000000000000594a96064343c11d--