
Scala example source code file (Either3.scala)
The Either3.scala Scala example source codepackage scalaz import scalaz.syntax.equal._ import scalaz.syntax.show._ sealed abstract class Either3[+A, +B, +C] extends Product with Serializable { def fold[Z](left: A => Z, middle: B => Z, right: C => Z): Z = this match { case Left3(a) => left(a) case Middle3(b) => middle(b) case Right3(c) => right(c) } def eitherLeft: (A \/ B) \/ C = this match { case Left3(a) => \/(\/(a)) case Middle3(b) => \/(\/(b)) case Right3(c) => \/(c) } def eitherRight: A \/ (B \/ C) = this match { case Left3(a) => \/(a) case Middle3(b) => \/(\/(b)) case Right3(c) => \/(\/(c)) } def leftOr[Z](z: => Z)(f: A => Z) = fold(f, _ => z, _ => z) def middleOr[Z](z: => Z)(f: B => Z) = fold(_ => z, f, _ => z) def rightOr[Z](z: => Z)(f: C => Z) = fold(_ => z, _ => z, f) } final case class Left3[+A, +B, +C](a: A) extends Either3[A, B, C] final case class Middle3[+A, +B, +C](b: B) extends Either3[A, B, C] final case class Right3[+A, +B, +C](c: C) extends Either3[A, B, C] object Either3 { def left3[A, B, C](a: A): Either3[A, B, C] = Left3(a) def middle3[A, B, C](b: B): Either3[A, B, C] = Middle3(b) def right3[A, B, C](c: C): Either3[A, B, C] = Right3(c) implicit def equal[A: Equal, B: Equal, C: Equal]: Equal[Either3[A, B, C]] = new Equal[Either3[A, B, C]] { def equal(e1: Either3[A, B, C], e2: Either3[A, B, C]) = (e1, e2) match { case (Left3(a1), Left3(a2)) => a1 === a2 case (Middle3(b1), Middle3(b2)) => b1 === b2 case (Right3(c1), Right3(c2)) => c1 === c2 case _ => false } } implicit def show[A: Show, B: Show, C: Show]: Show[Either3[A, B, C]] = new Show[Either3[A, B, C]] { override def show(v: Either3[A, B, C]) = v match { case Left3(a) => Cord("Left3(", a.shows, ")") case Middle3(b) => Cord("Middle3(", b.shows, ")") case Right3(c) => Cord("Right3(", c.shows, ")") } } } // vim: set ts=4 sw=4 et: Other Scala examples (source code examples)Here is a short list of links related to this Scala Either3.scala source code file: 
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