Scala - 基本语法

block of code as a param

— ex:
if we have a function like

def example(name:string){
    var char = name[0]
    char+'good'
 }={


}

the function example want to receive two params

• name
• the result of certain block of code (we need use {} for the code block)

if - else

var x = 30;

      if( x == 10 ){
         println("X 的值为 10");
      }else if( x == 20 ){
         println("X 的值为 20");
      }else if( x == 30 ){
         println("X 的值为 30");
      }else{
         println("无法判断 X 的值");
      }

这个语法很普通 js一样一样的

Pattern matching

def matchTest(x: Any): Any = x match {
   case 1 => "one"
   case "two" => 2
   case y:Int if y >4 => "more than four"
   case y: Int => "scala.Int"
   case _ => "many"
}

 println(matchTest("two"))
 println(matchTest("test"))
 println(matchTest(1))
 println(matchTest(6))

模式匹配首先很想switch.
逐个匹配然后返回值.
匹配比switch 更灵活

1. y:Int 可以加类型
2. y 算是把匹配项付给临时的变量
3. 可以给匹配项再加条件筛选 y:Int if y >4
4. _ 相当于匹配任何值,类似switch 的default