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                // new 操作符经历的五个步骤

// 1. 新建了一个对象。
// 2. 设置该对象的原型(__proto__)为构造函数的原型(prototype)
// 3. 将 new 运算符后面的构造函数的作用域指向这个新对象。(将构造函数的 this 指向新对象)
// 4. 执行 new 后面的构造函数
// 5. 返回新对象

function Person(name, age){ = name;
  this.age = age;

function Animal(name, age){ = name;
  this.age = age;

// args: constructor, ...arguments 
function mockNew(){
  let obj = {};
  let _constructor = [];
  obj.__proto__ = _constructor.prototype;
  _constructor.apply(obj, arguments)
  return obj;

let cat = mockNew(Animal, 'Cat', 10);
let caren = mockNew(Person, 'Caren', 10);

console.log('-----------cat ------------')
console.log(  // "[object Object]"
console.log(cat instanceof Animal);   // true
console.log(cat instanceof Object);   // true

console.log(  // "[object Object]"
console.log(caren instanceof Person);   // true
console.log(caren instanceof Object);   // true