/* Simple JavaScript Inheritance
         * By John Resig http://ejohn.org/
         * MIT Licensed.
         */
        // Inspired by base2 and Prototype
        (function(){
          var initializing = false, fnTest = /xyz/.test(function(){xyz;}) ? /\b_super\b/ : /.*/;

          // The base Class implementation (does nothing)
          this.Class = function(){};

          // Create a new Class that inherits from this class
          Class.extend = function(prop) {
            var _super = this.prototype;

            // Instantiate a base class (but only create the instance,
            // don't run the init constructor)
            initializing = true;
            var prototype = new this();
            initializing = false;

            // Copy the properties over onto the new prototype
            for (var name in prop) {
              // Check if we're overwriting an existing function
              prototype[name] = typeof prop[name] == "function" &&
                typeof _super[name] == "function" && fnTest.test(prop[name]) ?
                (function(name, fn){
                  return function() {
                    var tmp = this._super;

                    // Add a new ._super() method that is the same method
                    // but on the super-class
                    this._super = _super[name];

                    // The method only need to be bound temporarily, so we
                    // remove it when we're done executing
                    var ret = fn.apply(this, arguments);
                    this._super = tmp;

                    return ret;
                  };
                })(name, prop[name]) :
                prop[name];
            }

            // The dummy class constructor
            function Class() {
              // All construction is actually done in the init method
              if ( !initializing && this.init )
                this.init.apply(this, arguments);
            }

            // Populate our constructed prototype object
            Class.prototype = prototype;

            // Enforce the constructor to be what we expect
            Class.constructor = Class;

            // And make this class extendable
            Class.extend = arguments.callee;

            return Class;
          };
        })();