I am trying to extend my higherkinded type with a Functor bu kotlinlang #arrow

I am trying to extend my higherkinded type with a ...

kioba

11/08/2019, 2:38 PM

I am trying to extend my higherkinded type with a Functor. but I get the following error:

e: error: Arrow's annotations can only be used on Kotlin classes. Not valid for error.NonExistentClass

the code:

Copy code

@extension
interface ResultFunctor : Functor<ForResult> {
    override fun <A, B> ResultOf<A>.map(f: (A) -> B): Result<B> = this.fix().map(f)
}

What do I miss with here?