fc.Class = Class; // export

// class that all other classes will inherit from
function Class() { }

// called upon a class to create a subclass
Class.extend = function(members) {
	var superClass = this;
	var subClass;

	members = members || {};

	// ensure a constructor for the subclass, forwarding all arguments to the super-constructor if it doesn't exist
	if (hasOwnProp(members, 'constructor')) {
		subClass = members.constructor;
	}
	if (typeof subClass !== 'function') {
		subClass = members.constructor = function() {
			superClass.apply(this, arguments);
		};
	}

	// build the base prototype for the subclass, which is an new object chained to the superclass's prototype
	subClass.prototype = createObject(superClass.prototype);

	// copy each member variable/method onto the the subclass's prototype
	copyOwnProps(members, subClass.prototype);
	copyNativeMethods(members, subClass.prototype); // hack for IE8

	// copy over all class variables/methods to the subclass, such as `extend` and `mixin`
	copyOwnProps(superClass, subClass);

	return subClass;
};

// adds new member variables/methods to the class's prototype.
// can be called with another class, or a plain object hash containing new members.
Class.mixin = function(members) {
	copyOwnProps(members.prototype || members, this.prototype);
};