sax :: XMLReader :: dtd_handler
Return null if none has been registered.
	# Return the current DTD handler.
	#
	# Return `null` if none has been registered.
	fun dtd_handler: nullable DTDHandler is abstract
					lib/sax/xml_reader.nit:208,2--211,49
				
	redef fun dtd_handler do return model.dtd_handler
					lib/saxophonit/saxophonit.nit:76,2--50
				
	redef var dtd_handler = null is writable
					lib/sax/helpers/xml_filter_impl.nit:50,2--41