Scala's evaluation strategy

an evaluation strategy

 

Example of two evaluation strategies

 

Three examples

1. scala> def bar(x:Int,y:=>Int)=1
2. bar:(x:Int, y:=>Int)Int
4. scala> def loop():Int= loop
5. loop:()Int
7. scala> bar(1,loop) //正常秩序，不需要调用loop
8. res1:Int=1
10. scala> bar(loop,1) //死循环，需要调用loop