inheritance.md

chapter	15
pageNumber	96
description	Inheritance refers to the ability of an object (subclass) to inherit properties and methods from another object (superclass). JavaScript supports prototypal inheritance, which means that objects can inherit properties and methods directly from other objects, known as prototypes.

Inheritance

The inheritance is useful for code reusability purposes as it extends existing properties and methods of a class. The extends keyword is used to create a class inheritance.

class Car {
  constructor(brand) {
    this.carname = brand;
  }
  present() {
    return 'I have a ' + this.carname;
  }
}

class Model extends Car {
  constructor(brand, mod) {
    super(brand);
    this.model = mod;
  }
  show() {
    return this.present() + ', it is a ' + this.model;
  }
}

let myCar = new Model("Toyota", "Camry");
console.log(myCar.show()); // I have a Camry, it is a Toyota.

{% hint style="info" %} The prototype of the parent class must be an Object or null. {% endhint %}

The super method is used inside a constructor and refers to the parent class. With this, one can access the parent class properties and methods. In the example above we use super(brand) in the Model subclass so it can get that Car superclasses properties.

{% hint style="info" %} Super classes are the main classes used while subclasses are classes that are extended from superclasses. {% endhint %}