class.js

//简单模拟ES6的class实现
// class Animal {
//     constructor(name) {
//         this.name = name
//     }
//
//     sleep() {
//         console.log('animal is sleeping')
//     }
//
//     static staticFunc() {
//         console.log('staticFunc')
//     }
// }
//
// class Dog extends Animal {
//     constructor(name, color) {
//         super(name)
//         this.color = color
//     }
//
//     barking() {
//         console.log('wang!')
//     }
// }
//
// let brownTeddy = new Dog('teddy', 'brown')
// Dog.staticFunc()
// console.log(brownTeddy)
// brownTeddy.sleep()
// brownTeddy.barking()


function Animal(name) {
    this.name = name
}

Animal.staticFunc = function () {
    console.log('staticFunc')
}
Animal.prototype.sleep = function () {
    console.log('animal is sleeping')
}

function Dog(name, color) {
    Animal.call(this, name)
    this.color = color
}

//寄生组合式继承 + 构造函数之间的继承
function inherit(subType, superType) {
    //由于JavaScript引用类型和函数按值传递的特性，不能改变subType的引用地址
    subType.prototype = Object.create(superType.prototype, {
        constructor: {
            enumerable: false,
            configurable: true,
            writable: true,
            value: superType.constructor
        }
    })
    //子构造函数继承父构造函数(子类继承父类的静态方法和静态属性)
    Object.setPrototypeOf(subType, superType)
}

inherit(Dog, Animal)

//需要在继承之后再往Dog中添加原型方法，否则会被覆盖掉
Dog.prototype.barking = function () {
    console.log('wang!')
}


let brownTeddy = new Dog('teddy', 'brown')
Dog.staticFunc()
console.log(brownTeddy)
brownTeddy.sleep()
brownTeddy.barking()