+ -- | And provide a function for getting an "a" out of an (Xml a).
+ from_xml :: Xml a -> a
+
+ -- | Often we need to provide a key to use as a foreign key into
+ -- some container. If the instance "belongs" to some other object,
+ -- then it might need to be passed a key before it can un-XML
+ -- itself. For example, the XML version of 'NewsTeam' doesn't
+ -- contain a message ID which is part of its database type.
+ from_xml_fk :: AutoKey (Container a) -> Xml a -> a
+ from_xml_fk _ = from_xml