test.scala

Welcome to Scala 2.11.8 (Java HotSpot(TM) 64-Bit Server VM, Java 1.8.0_25).
Type in expressions for evaluation. Or try :help.

scala> import scala.language.higherKinds
import scala.language.higherKinds

scala> :paste
// Entering paste mode (ctrl-D to finish)

def foo[F[_], A](fa: F[A]): String = fa.toString

type IntConsumer[A] = Int => A

val f: IntConsumer[Int] = { x: Int => x * 2 }
foo(f)

// Exiting paste mode, now interpreting.

foo: [F[_], A](fa: F[A])String
defined type alias IntConsumer
f: IntConsumer[Int] = <function1>
res0: String = <function1>

scala>