class Animal {
  constructor(name, species, age) {
    this.name = name
    this.species = species
    this.age == age
  }
}

let dog = new Animal("Spot", "Dog", 4)

// 父类
class Point{
    constructor(x,y){
        this.x = x;
        this.y = y;
    }

    toString(){
        return this.x + ',' + this.y;
    }
}
// 子类
class ColorPoint extends Point{
    constructor(x,y,color){
        super(x,y); // 调用父类的构造函数
        this.color = color;
    }

    toString(){
        return this.color + ' ' + super.toString(); // 调用父类的toString()
    }
}

let cp = new ColorPoint(100,100,"red"); // 创建实例

console.log(cp); // 控制台输出