gistfile1.js

/*
 * Old and boring way to write classes.
 * Does not allow you do subclass native classes
 * (if you subclass an error, it'd just be [object Object])
 */

function Class() {
  this.foo = 1
}
Class.prototype.bar = 2

function SubClass() {
  Class.call(this)
  this.subfoo = 3
}
require('util').inherits(SubClass, Class)
SubClass.prototype.subbar = 4

// checking that all properties are in place
for (var i in new SubClass) console.log(i)

/*
 * Cool and useful way to write classes.
 * Allows you to subclass native classes preserving [[Class]] property
 * (if you subclass an error this way, it'd be [object Error])
 */

function Class() {
  var self = {}
  self.__proto__ = Class.prototype
  self.foo = 1
  return self
}
Class.prototype.bar = 2

function SubClass() {
  var self = Class()
  self.__proto__ = SubClass.prototype
  self.subfoo = 3
  return self
}
require('util').inherits(SubClass, Class)
SubClass.prototype.subbar = 4

// checking that all properties are in place
for (var i in new SubClass) console.log(i)