Scala【自定义while循环】

package com.li.chapter05
import java.util.concurrent.locks.Condition
object Test12_MyWhile {
  def main(args: Array[String]): Unit = {
    var n = 10
    // 1. 常规的while循环
    while (n >= 1){
      println(n)
      n -= 1
    }
    // 2. 用闭包实现一个函数，将代码块作为参数传入，递归调用
    def myWhile(condition: =>Boolean): (=>Unit)=>Unit = {
      // 内层函数需要递归调用，参数就是循环体
      def doLoop(op: =>Unit): Unit = {
        if (condition){
          op
          myWhile(condition)(op)
        }
      }
      doLoop _
    }
    println("=================")
    n = 10
    myWhile(n >= 1){
      println(n)
      n -= 1
    }
    // 3. 用匿名函数实现
    def myWhile2(condition: =>Boolean): (=>Unit)=>Unit = {
      // 内层函数需要递归调用，参数就是循环体
      op => {
        if (condition){
          op
          myWhile2(condition)(op)
        }
      }
    }
    println("=================")
    n = 10
    myWhile2(n >= 1){
      println(n)
      n -= 1
    }
    // 3. 用柯里化实现
    def myWhile3(condition: =>Boolean)(op: =>Unit): Unit = {
      if (condition){
        op
        myWhile3(condition)(op)
      }
    }
    println("=================")
    n = 10
    myWhile3({n >= 1})({
      println(n)
      n -= 1
    })
    //使用双参数代码块实现自定义while    
    def myWhile4(condition: =>Boolean,op: =>Unit): Unit ={
      if (condition){
        op
        myWhile4(condition,op)
      }
    }
    println("=================")
    n = 10
    myWhile4({n >= 1},{
      println(n)
      n -= 1
    })
  }
}