ES6 class类的函数实现return

 // 创建类
        class Person {
            constructor(name,age,hobby){
                this.name = name
                this.age = age
                this.hobby = hobby
            }
        }
        let LDH = new Person('刘德华',18,'唱歌')
        console.log(LDH) 

        //  继承类  
        class Man extends Person {
            constructor(name,age,hobby,say){
                super(name, age, hobby)
                this.say = say
            }
        }
        let XM = new Man('小明',20,'跳舞','说话')
        console.log(XM)

        function Person(name,age,hobby){
            // 判断this是否是Person的实例对象
            // 如果不是,说明是通过Person()来调用的
            // 此时,我们动手通过new来创建实例对象
            if(!(this instanceof Person)){
                return new Person(name,age,hobby)
            }
            this.name = name
            this.age = age
            this.hobby = hobby
        }
        const P1 = new Person()
        const P2 = Person()