try.scala

object Try {
  def apply[T](f: => T): Try[T] =
    try {
      Success(f)
    } catch {
      case NonFatal(e) => Failure(e)
    }
}

sealed trait Try[+T] {

  def flatMap[U](f: (T) => Try[U]): Try[U]
  def map[U](f: (T) => U): Try[U]
  def foreach[U](f: T => U): Unit
  def isSuccess: Boolean
  def isFailure: Boolean
  def getOrElse(f: => T): T = f

}

case class Success[+T](value: T) extends Try[T] {

  override def flatMap[U](f: T => Try[U]): Try[U] =
    try {
      f(value)
    } catch {
      case NonFatal(e) => Failure(e)
    }

  override def map[U](f: T => U): Try[U] = Try[U](f(value))
  override def foreach[U](f: T => U): Unit = f(value)
  override def getOrElse(f: () => T): T = value
  override def isSuccess = true
  override def isFailure = false

}

case class Failure[T <: Nothing](exception: Throwable) extends Try[T] {

  override def flatMap[U](f: (T) => Try[U]): Try[U] = this
  override def map[U](f: (T) => U): Try[U] = this
  override def foreach[U](f: T => U): Unit = {}
  override def isSuccess = false
  override def isFailure = true

}