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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

            
              // 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){
  this.name = name;
  this.age = age;
}

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

// args: constructor, ...arguments 
function mockNew(){
  let obj = {};
  let _constructor = [].shift.call(arguments);
  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(cat);
console.log(Object.prototype.toString.call(cat))  // "[object Object]"
console.log(cat instanceof Animal);   // true
console.log(cat instanceof Object);   // true

console.log('-----------caren------------')
console.log(caren); 
console.log(Object.prototype.toString.call(caren))  // "[object Object]"
console.log(caren instanceof Person);   // true
console.log(caren instanceof Object);   // true


            
          
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