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GeezerVison is showing id.javascript.info — Kesalahan saat membuat sebuah _instance_

Kesalahan saat membuat sebuah _instance_

pentingnya: 5

Berikut kode dengan Rabbit extending Animal.

Sayangnya, objek Rabbit tidak dapat dibuat. Apa yang salah? Perbaiki!.

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);

Itu karena konstruktor turunan harus memanggil super().

Berikut kode yang benar:

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"); // sekarang oke
alert(rabbit.name); // White Rabbit

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