I've got something like

interface MyInterface<R> {
    fun doIt(): R
}

object MyImpl : MyInterface<String> {
    override fun doIt(): String = "hello"
}

object MyOtherImpl : MyInterface<Int> {
    override fun doIt(): Int = 5
}

which works fine. now say I've got

fun <R> foo(impl: MyInterface<R>): R = impl.doIt()

is it possible to add a default value to

impl

?

fun <R> foo(impl: MyInterface<R> = MyImpl) = impl.doIt()

doesn't compile. the best I could come up with is to also add an overload of `foo`:

fun foo() = foo(MyImpl)

.

the overload is your only option afaik

MyImpl

emits

String

, while

MyInterface<R>

emits

R

,

R

could be something other than

String

, so you can't assign

impl: MyInterface<R>

with

MyImpl

.

maybe I am. I'm trying to emulate Rust's associated type.