event.js

var listener = function ( fun ) {
	return function ( e ) {
		//thank you IE for the wonderful fish
		e = e || window.event;
		e.target = e.target || e.srcElement;
		e.stopPropagation = e.stopPropagation || function () {
			this.cancelBubble = true;
		};
		e.preventDefault = e.preventDefault || function () {
			this.returnValue = false;
		};

		//because the IE event model will pass window as the `this` value, we'll have to select the element ourselves (not that it's that hard)
		//did I mention IE doesn't have .currentTarget, and it's probably necessary to reimplement event bubbling? yeah, thought so
		return fun.call( e.currentTarget, e );
	};
};

var addListener = function ( elem, type, fun ) {
	if ( elem.addEventListener ) {
		elem.addEventListener( type, listener(fun), false );
	}
	else if ( elem.attachEvent ) {
		elem.attachEvent( 'on' + type, listener(fun) );
	}
};

//since `fun` is called indirectly, via `listener`, how is it possible to remove a specific listener?
//there's the possibility of going into giant arrays, but it's probably best not to
var removeListener = function ( elem, type, fun ) { };