Re: [RFC] Traits with interfaces

On Thu, Feb 18, 2016 at 2:16 PM, Chase Peeler <chasepeeler@gmail.com> wrote: > > > On Thu, Feb 18, 2016 at 1:29 PM Nikita Popov <nikita.ppv@gmail.com> wrote: > >> HHVM already supports "trait Foo implements Iface" with the semantics that >> the interface is also implemented by the using class. >> >> Additionally HHVM supports a notion of "require implements Iface" which >> means that the using class must implement this interface. >> > This was mentioned in the original traits RFC, but never got voted or implemented: https://wiki.php.net/rfc/horizontalreuse#requiring_composing_class_to_implement_interface It's orthogonal to this RFC. > >> Why should it matter if the class using the trait actually implements the > interface? If the person just wants the functionality, but, for whatever > reason, doesn't want to actually implement the interface, why should it > matter? > > I think the trait should HELP the person implementing an interface. The > trait should be able to say (whether via comments or an engine enforceable > construct) "Hey, I've done everything needed for you to implement this > interface" but, at no time, should the trait force the class utilizing it > to interact (via extend or implement or use) a 3rd artifact. > > trait foo implements myinterface {} > class bar { use foo;} > class baz implements myinterface { use foo;} > > Both of the above should be legal, and $myBar instanceof myinterface > should return false; > This is Proposal 1 in the new draft of my RFC: https://wiki.php.net/rfc/traits-with-interfaces Does that proposal sound like what you'd want? Cheers -- Kevin >