MrKou47

let carFactory = (function (name) {
  function Benz() {
    this.name = 'benz';
  }
  function BMW() {
    this.name = 'bmw';
  }
  return function(name) {
    switch (name) {
      case 'benz':

MrKou47

function Car() {
  console.log(this);
  console.log(this instanceof Car);
  this.a = 'i am a ';
}

var t = new Car();
var tt = Car();
console.log(t);

MrKou47

/**
 * 单例模式 
 * 避免重复创建相同对象
 * example: 
 * let a = new TestClass();
 * let b = new TestClass();
 * a === b // false
 * 如何a===b 为 true
 */