Scala example source code file (CompositionTest.scala)

This example Scala source code file (CompositionTest.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

compositiontest, either, list, nonemptylist, oneand, optionlist, speclite, traverse1

The CompositionTest.scala Scala example source code

package scalaz

import std.AllInstances._
import scalaz.scalacheck.ScalazProperties._
import scalaz.scalacheck.ScalazArbitrary._

object CompositionTest extends SpecLite {
  type OptionList[α] = Option[List[α]]

  implicit val optionListApplicative = ApplicativePlus[Option].compose[List]
  implicit val optionListTraverse = Traverse[Option].compose[List]
  implicit val oneAndOptNelTraverse = Traverse1[OneAnd[Option, ?]].compose[NonEmptyList]

  checkAll(applicative.laws[OptionList])
  checkAll(plusEmpty.laws[OptionList])
  checkAll(traverse.laws[OptionList])
  checkAll(traverse1.laws[λ[α => OneAnd[Option, NonEmptyList[α]]]])

  implicit val eitherTuple2 = Bitraverse[Either].compose[Tuple2]
  checkAll(bitraverse.laws[λ[(α, β) => Either[(α, β), (α, β)]]])

  implicit val listEitherBitraverse = Traverse[List].bicompose[Either]
  checkAll(bitraverse.laws[λ[(α, β) => List[Either[α, β]]]])
}