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// SCALA PHANTOM TYPES EXAMPLES

// 1 SIMPLE EXAMPLE 
trait DoorStatus 
trait DoorOpened extends DoorStatus
trait DoorClosed extends DoorStatus

case class Door[Status <: DoorStatus] private () {

  def close[T >: Status <: DoorOpened](): Door[DoorClosed] = Door[DoorClosed]()

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trait Acceptable[T]

object Acceptable {
  implicit object LongOK extends Acceptable[Long]
  implicit object IntOK extends Acceptable[Int]
}


object A {
  def f[T : Acceptable](t : T) = t

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// 1 example
class A(name: String) {
  case class B(nr: Int)

  def add(first: B, second: B): Int = first.nr + second.nr
}

val a1 = new A(name = "first")
val a2 = new A(name = "second")

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import scalaz.\/
import scalaz.syntax.either._

object Example2 {
  // This example simulates error handling for a simple three tier web application
  //
  // The tiers are:
  // - the HTTP service
  // - a user authentication layer
  // - a database layer

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/**
 * Part Zero : 10:15 Saturday Night
 *
 * (In which we will see how to let the type system help you handle failure)...
 *
 * First let's define a domain. (All the following requires scala 2.9.x and scalaz 6.0)
 */

import scalaz._
import Scalaz._