Scala入门操作

定义变量

var
定义的变量可变
val
不可变

scala> val x1 = "333"
val x1: String = 333

scala> var x1 = "444"
var x1: String = 444

scala> val x1 = "333"
val x1: String = 333

scala> x1 ="e"
          ^
       error: reassignment to val

定义函数

 def max(x:Int,y:Int):Int = {
    
    
      if(y>x)x
      else y
      }
      
scala> max(5,6)
val res0: Int = 5

可以这样定义

scala> def max(x:Int,y:Int)=if(y>x)x else y

scala> def greet()=println("hello")
def greet(): Unit

scala> greet()
hello

Unit是返回的结果