inheritance.js

//Inheritance example in js

class Rectangle {
  constructor(length, width) {
    this.length = length;
    this.width = width;
  }

  Area() {
    return this.length * this.width;
  }
}

const FirstRectangle = new Rectangle(2, 3);
console.log(FirstRectangle.Area());

//extending to square

class Square extends Rectangle {
  constructor(side) {
    super(side, side);
  }
}

const FirstSquare = new Square(2);
console.log(FirstSquare.Area());

//Another example

class Person {
  constructor(name, age, gender) {
    this.name = name;
    this.age = age;
    this.gender = gender;
  }

  greeting() {
    return `Hi! I'm ${this.name}`;
  }

  farewell() {
    return `${this.name} has left the building. Bye for now!`;
  }
}

const Amy = new Person("Amy", 19, "female");
Amy.farewell();

//extending to Teacher

class Teacher extends Person {
  constructor(name, age, gender, subject) {
    super(name, age, gender);
    this.subject = subject;
  }
}

let snape = new Teacher("Severus", 58, "male", "Dark arts");
snape.greeting();

return this.length * this.width