Chapter4.scala

package chapter4

/**
  * Created by hoshi on 1/15/16.
  */
object MainObj {
  val areaOfRect: (Int, Int) => Int = (width: Int, height: Int) => {
    width * height
  }
  // Same
  val areaOfRect2: Function2[Int, Int, Int] = (width: Int, height: Int) => {
    width * height
  }
  // Same
  val areaOfRect3: (Int, Int) => Int = new Function2[Int, Int, Int] {
    def apply(width: Int, height: Int): Int = {
      width * height
    }
  }

  def operation(functionparam : (Int, Int) => Int) {
    println(functionparam(4,4))
  }

  def main(args: Array[String]) {
    println(areaOfRect(5, 3))
    println(areaOfRect2(5, 3))
    println(areaOfRect3(5, 3))

    var doubler = (i: Int) => { i * 2 }
    println(doubler(5))

    val add = (x:Int, y:Int) => { x + y }
    val sub = (x:Int, y:Int) => { x - y }
    operation(add)
    operation(sub)
  }
}