Namuna yaratishda xato

Rabbit kengaytirilgan Animal kodi.

Afsuski, Rabbit obyektlarini yaratish mumkin emas. Nima bo’ldi? Tuzating.

class Animal {

  constructor(name) {
    this.name = name;
  }

}

class Rabbit extends Animal {
  constructor(name) {
    this.name = name;
    this.created = Date.now();
  }
}

let rabbit = new Rabbit("White Rabbit"); // Error: this is not defined
alert(rabbit.name);

Buning sababi, bola konstruktor super() ni chaqirishi kerak.

Mana tuzatilgan kod:

class Animal {

  constructor(name) {
    this.name = name;
  }

}

class Rabbit extends Animal {
  constructor(name) {
    super(name);
    this.created = Date.now();
  }
}

let rabbit = new Rabbit("White Rabbit"); //yaxshi hozir
alert(rabbit.name); // White Rabbit