Hash.prototype.without = function() {
    var values = $A(arguments);
	var retHash = $H();
    this.each(function(entry) {
		if(!values.include(entry.key))
			retHash.set(entry.key, entry.value);
    });
	return retHash;
}

Element.insertAfter = function(insert, element) {
	if (element.nextSibling) element.parentNode.insertBefore(insert, element.nextSibling);
	else element.parentNode.appendChild(insert);
}

// Fix exceptions thrown thrown when removing an element with no parent
Element._remove = Element.remove;
Element.remove = function(element) {
	element = $(element);
	if (element.parentNode)
		return Element._remove(element);
}