object.js

const now = new Date();
console.log(now);
console.log(now.getFullYear());
console.log(now.getMonth() + 1);
console.log(now.getDate());
console.log(now.getTime());
console.log(now.__proto__);
console.log(now.__proto__.__proto__);
console.log(now.__proto__.__proto__.__proto__);

const numRegx = /[0-9]+/;
console.log(numRegx.test("我是1只漆黑小猫"));
console.log(numRegx.test("我是一只漆黑小猫"));

const text = "复旦中文真是要完蛋了啊";
console.log(text);
const safeText = text.replace(/复旦中文/, "****");
console.log(safeText);

//原型本质

const obj1 = {};
console.log(obj1.__proto__);
console.log(obj1.__proto__ === Object.prototype);
console.log(obj1.__proto__.__proto__);

//函数的双重身份
function foo() {};
//函数是对象
console.log(foo.__proto__);
const foo2 = new foo();
//函数自己拥有prototype
console.log(foo.prototype === foo2.__proto__);
//作为实例创建的foo2的原型是foo
console.log(foo.__proto__ == Function.prototype);
console.log(Function.prototype.__proto__ == Object.prototype);
console.log(Object.__proto__);

// function myNew(fn, ...args){
//     const obj = Object.create(fn.prototype)
//     const result = fn.apply(obj, args)
//     return result instanceof Object ? result : obj
// }

//我按指定一个全局变量，这样可以改变下面car.model的结果
globalThis.model = "Teala"
function car(model){
    console.log("正在执行car函数")
    this.model = model;
    this.year = 2024

    return function(){
        return this.model;
    }
}

const c = new car("特斯拉")
console.log(c.model);//return的是一个函数，盲猜肯定undefined这个model属性
console.log(c());//这里的this应该是全局，找不到，应该是undefined
console.log(c instanceof car);//c实际上即成的已经不是prototype，而已return回来的函数吧？

//class的本质
class Person {
    constructor(name) {
        this.name = name
    }

    say(){
        return "hello" + this.name;
    }
}
 const greeting = new Person("liqi");
 console.log(greeting.name);
 console.log(greeting.say());

 //易错考点
 console.log(Function.__proto__ === Function.prototype);
 console.log(Object.__proto__ == Function.prototype);
 console.log(typeof Object);

 console.log(Function.prototype.__proto__ == Object.prototype);

 console.log(Object.prototype.__proto__ === null);

 let str = "liqi";
str.age = 3;
console.log(str.age);