Scala-高阶函数

map的方法filter

3、

object gaojie {

  def main(args: Array[String]): Unit = {
    (1 to 10).map("*" * _).foreach(println _);
    //数组1 到 10 调用高阶函数map（）映射 将每一行乘以对应的*
    //然后在依次打印这个数组
  }
}  

4、reduce化简

object gaojie {

  def main(args: Array[String]): Unit = {
    val arr = Array(1,3,4,5);
   // val result =  arr.reduceLeft(_ + _);
   // val result = arr.reduceRight(_ * _);
   //val result = arr.reduceRight(_ - _);
   //1-(3-(4-5))
    val result = arr.reduceLeft(_ - _);
   //(((1-3)-4)-5)
    println(result);

  }
}

5、柯里化的过程
两参变一参

object gaojie {

  def main(args: Array[String]): Unit = {

    def fun(a:Int) = {(x : Int)=> a * x;}
    println(fun(1)(2));

  }
}

6、控制抽象

object controllAbstract {

  def newThread(block: Unit){
    new Thread(){
      override def run() ={
        block;
      }
    }.start();
  }

  def main(args: Array[String]): Unit = {
    newThread{
      ( 1 to 10).foreach(e => {
        val tname = Thread.currentThread().getName();
        println(tname + ":"+e);
      })
    }
  }
}
打印结果：
main:1
main:2
main:3
main:4
main:5
main:6
main:7
main:8
main:9
main:10