object oriented programming in js

index.js

// Try edit message
// Object oriented prograaming: 4 principles
// 1. Encapsulation
// 2. Inheritance
// 3. Composition
// 4. Polymorphism

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

  printArea(){
    console.log('area is: ', this.length * this.width);
  }apis
  

  printParameter(){
    console.log('parameter is: ', 2(this.length + this.width));
  }
}

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

class NewSquare{
  constructor(side){
    //composition
    this.myRectangle = new Rectangle(side, side);
  }

  printArea(){
    this.myRectangle.printArea();
  }

  printParameter(){
    this.myRectangle.printParameter();
  }
}

// consumer
const myRectangle = new Rectangle(2, 3);
myRectangle.printArea();

const mySquare = new Square(2);
mySquare.printArea();

const myNewSquare = new NewSquare(2);
myNewSquare.printArea();

// polymorphism
function add(arg1, arg2){
  return arg1 + arg2;
}

console.log(add(1,2));
console.log(add("1","2"));
console.log(add("abc","def"));