instanceof operator

The instanceof operator is a way to narrow down the type of a variable. It is used to check if an object is an instance of a class.

class Bird {
  fly() {
    console.log('flying...');
  }
  layEggs() {
    console.log('laying eggs...');
  }
}

const pet = new Bird();

// instanceof
if (pet instanceof Bird) {
  pet.fly();
} else {
  console.log('pet is not a bird');
}

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