闭包的完美封装

var obj = function (arg1,arg2) {    var name = arg1;     var age = arg2;    function privateFunction() {          return name;    }    var globalObj = {          say:function(){               return this.sayAge();          },          sayName:function(){               alert(name);          },          sayAge:function(){               alert(age);          },          sayP:function(){               return privateFunction();          }     };     function obj(){}     obj.prototype = globalObj;     return new obj(name);}('hello world!',2);obj.say();alert(obj.sayP());