Tag: require	Specify a file that must be loaded. If the file is already loaded, it will not be loaded again.
Attrib Name	Type	Possible Values	Description
__filename	string	null	The full path of the file that has been loaded.
file	string	null	Path to XML file to require for use. Specified file is only ever loaded once.
onerror	function	(node, error_message)	Function to call when an error occurs