EmitterAPI.js

// returns the ClickEmitter object (and creates a new ClickEmitter)
// should return an error when the event type does not have a matched
// emitter class (defined by defineEmitter)
var emitter = myElement.on('click');

// Emitter methods: create, add, remove
// returns a Listener object
var listener = emitter.create(function(event){
	event instanceof ClickEvent // true
});

// creates a listener and attaches it
emitter.add(function(event){

});

// remove. won't be used as public API, but listener.detach() will be
// used usually
emitter.remove(functionReference);

// listener methods
// listener is a instanceof Listener. A Emitter can choose to return a 
// ScrollListener which has some extra stuff
listener.attach();
listener.detach();
listener.once();
listener.throttle();

// a Accessor for Emitters, where all event types are defined.
// Emitter classes can decide how to bind the listeners to the actual
// object
var Emitter = new Class({
	initialize: function(Object object);
	add: function(Function fn);
	remove: function(Function fn);
	trigger: function(Event event);
});

Node.defineEmitter('click', new Class({ 
	Extends: DOMEmitter, 
	name: 'click' 
}));