Scala 惰性加载

 1 package com.atguigu.chapter04
 2
 3 object Test_Lazy {
 4   def main(args: Array[String]): Unit = {
 5     lazy val result : Int = sum(13,12)
 6     println("1. 函数调用")
 7     println("2. result = " + result)
 8   }
 9   def sum(a: Int ,b:Int):Int = {
10     println("3. sum调用！")
11     a+b
12   }
13 }