FMWK = { 'hulk' : 'smash' } FMWK.button = function() {   var _this = this; console.log(this.hasOwnProperty('hulk') ? "HULK SMASH" : ""); this.el = document.createElement('button');   ['hide','show'].forEach(function(method){     FMWK.button.prototype[method] = function(){       $(_this.el)[method].apply($(_this.el), Array.prototype.slice.call(arguments));      }   }); return this; } var b1 = new FMWK.button(); var b2 = new FMWK.button(); b1.hide() // fires on b2