Scala example source code file (InvariantFunctorTest.scala)

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Java - Scala tags/keywords

bijection, int, invariantfunctortest, isoset, num, speclite

The InvariantFunctorTest.scala Scala example source code

package scalaz

import BijectionT.{Bijection, liftBijection}
import Id.Id
import Isomorphism.{<=>, IsoSet}
import std.AllInstances._
import std.option.some
import syntax.invariantFunctor._

object InvariantFunctorTest extends SpecLite {

  "xmap" in {
    some(1).xmap[Int](_ + 1, _ - 1) must_===(some(2))
  }

  "xmap iso" in {
    val succI: Int <=> Int = new IsoSet[Int, Int] {
      def to = (_: Int) + 1
      def from = (_: Int) - 1
    }
    some(1) xmapi succI must_===(some(2))
  }

  "xmap bijection" in {
    val succB: Bijection[Int, Int] = liftBijection[Id, Id, Int, Int](_ + 1, _ - 1)
    some(1) xmapb succB must_===(some(2))
  }

  case class Num(x: Int)
  implicit val showNum = Show.showA[Num]
  implicit val eqNum = Equal.equalA[Num]
}