ES6 - Tworzenie klasy.js

      class House {
          constructor() {
              this.doors = 3;
              this.windows = 10;
          }
      }
      var myHouse = new House();
      
      //rozszerz klase 
      
      class newSkyscraper extends House {
	      constructor () {
	    	super();
	    	this.name = "sky"
	      }
      }