Re: RFC: Trait expects interface

On Tue, Jan 4, 2022 at 10:35 PM Kirill Nesmeyanov <nesk@xakep.ru> wrote: > How relevant do you think this idea/proposal is? And what possible > problems or solutions will this entail in the future? > I'm not convinced there's a reasonable need for it. The very nature of finding yourself in a situation where you want any class using a trait to also require other things outside the trait kind of suggests you really want to be using interfaces or abstract classes anyway. There is a similar concept for what I think you're trying to achieve in Java, though, which could also be useful in PHP if it was feasible within the engine - the ability to provide a default method implementation on interfaces themselves. Short of that, we can already effectively get there with the tools we have; an abstract class can use a trait and define abstract or concrete methods, and in doing so can implement one or more interfaces. Obviously traits can also declare abstract methods but I assume it's the identity/type aspect of an interface you want here which isn't satisfied by that approach. Also worth noting, although I can't say I'm familiar with the mechanics of traits in PHP's implementation, my understanding has always been that they're effectively compiler-level copy and paste in to a class so I'm not sure what interfaces are implemented by the class (or conversely allowing a trait to implement an interface) would be readily achievable. That's my two cents, good luck with whatever you're trying to do anyway. - David > -- > Kirill Nesmeyanov