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/* 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.prototype.constructor = Class;

		// And make this class extendable
		Class.extend = arguments.callee;
		
		return Class;
	};
})();

if(!(typeof exports === 'undefined')) {
    exports.Class = Class;
}

//=========================================================================
var Person = Class.extend( {
  init: function() { console.log('Created Person'); },
  speak: function() { console.log('Person Speaking'); }
});

var p = new Person();
p.speak();

var Guy = Person.extend({
  init: function() { this._super(); console.log( 'Create Guy'); },
  speak: function() { this._super(); console.log( "I'm a Guy!" ); }
});

var bob = new Guy();
bob.speak();

var Girl = Person.extend( {
  init: function() { console.log( "Created Girl" ); },
  speak: function() { console.log( "I'm a Girl!" ); }
});

var jill = new Girl();
jill.speak();