Inheritance models that provides: - Use of the new operator. - Proper prototype chain and public methods attached to the prototype. - Private methods (through Function.prototype.call or Function.prototype.apply). - Class._super_ attribute to access base class' prototype (for calling super-methods easily).

inherit.js

var inherit = function (init) {
  var base, ctor;
  
  base = this;
  
  ctor = function () {
    if (typeof init === 'function') {
      init.apply(this, arguments);
    }
  };
  ctor.prototype = new base();
  ctor._super_ = base.prototype;
  
  ctor.inherit = inherit;

  return ctor;
}

var Base = (function() {

  // TODO: Prevent calling without new.
  var Base = function () {}

  function private () {
    console.log(this.foo);
  }

  Base.prototype.public = function (name) {
    console.log("Base's public " + name);
    private.apply(this);
  };
  
  Base.prototype.aMethod = function () {
    console.log("Base method");
  }
  
  return Base;
})();

Base.inherit = inherit;


var Child = (function () {

  var Child = Base.inherit(function (){
    this.foo = 'bar';
  });

  Child.prototype.public = function (name) {
    console.log("Child's public");
    Child._super_.public.call(this, name);
  };
  
  return Child;
})();

var Third = Child.inherit();

inheritance.js

var Base = (function() {

  // TODO: Prevent calling without new.
  var Base = function () {}

  function private () {
    console.log(this.foo);
  }

  Base.prototype.public = function (name) {
    console.log("Base's public " + name);
    private.apply(this);
  };
  
  return Base;
})();


var Child = (function () {

  var Child;
  
  Child = function () {
    this.foo = 'bar';
  };
  Child._super_ = Base.prototype;
  
  // Here we set the prototype chain straight and enable inheritance.
  Child.prototype = new Base();

  Child.prototype.public = function (name) {
    console.log("Child's public");
    Child._super_.public.call(this, name);
  };
  
  return Child;
})();