Scala example source code file (ComonadTrans.scala)

This example Scala source code file (ComonadTrans.scala) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Scala by Example" ^TM.

Learn more about this Scala project at its project page.

Java - Scala tags/keywords

cobind, cohoist, comonadtrans

The ComonadTrans.scala Scala example source code

package scalaz

trait ComonadTrans[F[_[_], _]] {
  def lower[G[_]: Cobind, A](a: F[G, A]): G[A]
}

object ComonadTrans {
  def apply[F[_[_], _]](implicit F: ComonadTrans[F]): ComonadTrans[F] = F
}

trait Cohoist[F[_[_], _]] extends ComonadTrans[F] {
  def cohoist[M[_], N[_]: Comonad](f: M ~> N): F[M, ?] ~> F[N, ?]
}

object Cohoist {
  def apply[F[_[_], _]](implicit F: Cohoist[F]): Cohoist[F] = F
}