12一个递归调用的实例，以及引用数据类型值的复制

作者: An的杂货铺 | 来源:发表于2019-03-11 15:43 被阅读0次

<!DOCTYPE html>
<html>
<head>
    <title></title>
</head>
<body>

</body>
<script type="text/javascript">
    function factorial(num){
      if(num<=1){
          return 1;
      }else{
          return num*arguments.callee(num-1);  //
      }
    }
  // function factorial(num){
  //     if(num<=1){
  //         return 1;
  //     }else{
  //         return num*factorial(num-1);
  //     }
  //   }

    var trueFactorial = factorial;
    //此处是值的复制的过程
    factorial = function(){
      return 0;
    }
   alert(trueFactorial(5));//120
   alert(factorial(5));//0

   var objone = {
       name:'tom',
       age:28
   }
   var objtwo = {
    name:'lili',
    age:30
   }
   objtwo.name = objone.name;
   objone.name = 'huahua';
   console.log(objtwo);
   console.log(objone);
</script>
</html>

如图

image.png