gistfile1.js

var util = require('util');


// Let's create a class with some abstract methods
 
function Animal() {
	console.log('A new', this.name, 'is born!')
}

Animal.prototype.talk = function() {
	console.log('The', this.name, 'goes', this.action)
}


// Now let's extend our abstract class

function Cat() {
	
}

util.inherits(Cat, Animal);

Cat.prototype.name = 'cat';
Cat.prototype.action = 'miaow';


function Kitten() {
	
}

util.inherits(Kitten, Cat);

Kitten.prototype.name = 'kitten';


function Dog() {
	
}

util.inherits(Dog, Animal);

Dog.prototype.name = 'dog';
Dog.prototype.action = 'woof';

 
// Now, let's generate some new objects using our classes
 
var mycat = new Cat;
var mykitten = new Kitten;
var mydog = new Dog;

mydog.action = 'woof woof woof'
 
 
// Now we can call the abstract methods for each of our objects
 
mycat.talk();
mykitten.talk();
mydog.talk();