Scala example source code file (CoyonedaTest.scala)

This example Scala source code file (CoyonedaTest.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

applicative, applicativeplus, apply, cobind, comonad, equal, foldable, foldable1, functor, monadplus, order, plusempty, traverse1

The CoyonedaTest.scala Scala example source code

package scalaz

import std.option._, std.anyVal._
import org.scalacheck.Arbitrary
import scalaz.scalacheck.ScalazProperties._
import scalaz.scalacheck.ScalazArbitrary._
import scalaz.scalacheck.ScalaCheckBinding._

object CoyonedaTest extends SpecLite {

  implicit def coyonedaArb[F[_], A](implicit A: Arbitrary[F[A]]): Arbitrary[Coyoneda[F, A]] =
    Functor[Arbitrary].map(A)(Coyoneda.lift)

  type CoyonedaOption[A] = Coyoneda[Option, A]
  type CoyonedaNel[A] = Coyoneda[NonEmptyList, A]

  checkAll(monadPlus.strongLaws[CoyonedaOption])
  checkAll(bindRec.laws[CoyonedaOption])
  checkAll(cobind.laws[CoyonedaOption])
  checkAll(traverse.laws[CoyonedaOption])
  checkAll(order.laws[Coyoneda[Option, Int]])
  checkAll(foldable.laws[CoyonedaOption](implicitly, Coyoneda.coyonedaFoldable, implicitly))

  checkAll(monad.laws[CoyonedaNel])
  checkAll(bindRec.laws[CoyonedaNel])
  checkAll(plus.laws[CoyonedaNel])
  checkAll(comonad.laws[CoyonedaNel])
  checkAll(traverse1.laws[CoyonedaNel])
  checkAll(order.laws[Coyoneda[NonEmptyList, Int]])
  checkAll(foldable1.laws[CoyonedaNel](implicitly, Coyoneda.coyonedaFoldable1, implicitly))

  object instances {
    def functor[F[_]] = Functor[Coyoneda[F, ?]]
    def contravariant[F[_]: Functor: Contravariant] = Contravariant[Coyoneda[F, ?]]
    def foldable[F[_]: Foldable] = Foldable[Coyoneda[F, ?]]
    def foldable1[F[_]: Foldable1] = Foldable1[Coyoneda[F, ?]]
    def traverse[F[_]: Traverse] = Traverse[Coyoneda[F, ?]]
    def traverse1[F[_]: Traverse1] = Traverse1[Coyoneda[F, ?]]
    def apply[F[_]: Apply] = Apply[Coyoneda[F, ?]]
    def applicative[F[_]: Applicative] = Applicative[Coyoneda[F, ?]]
    def applicativePlus[F[_]: ApplicativePlus] = ApplicativePlus[Coyoneda[F, ?]]
    def bind[F[_]: Bind] = Bind[Coyoneda[F, ?]]
    def bindRec[F[_]: BindRec] = BindRec[Coyoneda[F, ?]]
    def monad[F[_]: Monad] = Monad[Coyoneda[F, ?]]
    def monadPlus[F[_]: MonadPlus] = MonadPlus[Coyoneda[F, ?]]
    def plus[F[_]: Functor: Plus] = Plus[Coyoneda[F, ?]]
    def plusEmpty[F[_]: Functor: PlusEmpty] = PlusEmpty[Coyoneda[F, ?]]
    def cobind[F[_]: Cobind] = Cobind[Coyoneda[F, ?]]
    def comonad[F[_]: Comonad] = Comonad[Coyoneda[F, ?]]
    def equal[F[_], A](implicit F: Functor[F], E: Equal[F[A]]) = Equal[Coyoneda[F, A]]
    def order[F[_], A](implicit F: Functor[F], E: Order[F[A]]) = Order[Coyoneda[F, A]]

    // checking absence of ambiguity
    def functor[F[_]: MonadPlus: Comonad: Traverse1] = Functor[Coyoneda[F, ?]]
    def foldable[F[_]: Foldable1] = Foldable[Coyoneda[F, ?]]
    def foldable[F[_]: Traverse1] = Foldable[Coyoneda[F, ?]]
    def foldable1[F[_]: Traverse1] = Foldable1[Coyoneda[F, ?]]
    def traverse[F[_]: Traverse1] = Traverse[Coyoneda[F, ?]]
    def apply[F[_]: MonadPlus] = Apply[Coyoneda[F, ?]]
    def applicative[F[_]: MonadPlus] = Applicative[Coyoneda[F, ?]]
    def applicativePlus[F[_]: MonadPlus] = ApplicativePlus[Coyoneda[F, ?]]
    def bind[F[_]: MonadPlus] = Bind[Coyoneda[F, ?]]
    def monad[F[_]: MonadPlus] = Monad[Coyoneda[F, ?]]
    def plus[F[_]: MonadPlus] = Plus[Coyoneda[F, ?]]
    def plusEmpty[F[_]: MonadPlus] = PlusEmpty[Coyoneda[F, ?]]
    def cobind[F[_]: Comonad] = Cobind[Coyoneda[F, ?]]
    def equal[F[_], A](implicit F: Functor[F], E: Order[F[A]]) = Equal[Coyoneda[F, A]]
  }

}