JS Bin// source https://jsbin.com/miviziy

jsbin.miviziy.js

//class emulation adding inheritance
var Class = function(parent){
  
  var klass = function(){
    this.init.apply(this, arguments);
  };
   // Change klass' prototype
  //If a parent is passed to the Class constructor
  //we make sure any subclasses share the same prototype.
  //creating a temporary anonymous function prevents instances
  //from being created when a class is inherited. 
  //here is that only instance properties, not class properties, are inherited
  if (parent) {
    var subclass = function() {};
    subclass.prototype = parent.prototype;
    klass.prototype = new subclass;
  };
  
  klass.prototype.init = function(){};
  
  // Shortcut to access prototype
  klass.fn = klass.prototype;
  
  // Adding a proxy function
  klass.proxy = function(func){
    var self = this;
    return(function(){
      return func.apply(self, arguments);
    });
  }
  
  // Add the function on instances too
  klass.fn.proxy = klass.proxy;
  
  // Shortcut to access class
  klass.fn.parent = klass;
  
  klass._super = klass.__proto__;
  
  // Adding class properties
  klass.extend = function(obj){
    var extended = obj.extended;
      for(var i in obj){
          klass[i] = obj[i];
      }
      if (extended) extended(klass)
  };
  
  // Adding instance properties
  klass.include = function(obj){
    var included = obj.included;
    for(var i in obj){
      klass.fn[i] = obj[i];
    }
    if (included) included(klass)
  };  
  
  return klass;
 };
   
 //usage  
var Animal = new Class; 
Animal.include({
  breath: function(){
    console.log('breath')
  }
});  
var Cat = new Class(Animal);    
var tommy = new Cat; 
tommy.breath();