1.方法转换为函数 scala> def m(x:Int,y:Int) = x*y m: (x: Int, y: Int)Int scala> val f = m _ f: (Int, Int) => Int = 2.集合中的每一个元素 scala> val list = List(1,2,3,4) list: List[Int] = List(1, 2, 3, 4) scala> val list2 = list.map(_ * 5) list2: List[I