ComposedFunctors.scala

import scala.concurrent.Future
import scala.language.higherKinds
import scalaz.Functor

/**
  * Created by kubukoz on 25/01/2017.
  */
object ComposedFunctors {
  implicit class ComposedMapOps[F[_], G[_], T](val functor: F[G[T]]) extends AnyVal {
    def cmap[U](f: T => U)(implicit G: Functor[G], F: Functor[F]): F[G[U]] = (F compose G).map(functor)(f)
  }

  
  //sample
  import scalaz.std.scalaFuture._
  import scalaz.std.option._
  import scala.concurrent.ExecutionContext.Implicits.global


  val x: Future[Option[Int]] = Future(Option(5)).cmap(_ + 5)
}