+<!-- enumerated and flags types -->
+<!-- each value element maps a nick to a numeric value -->
+<!ELEMENT enum (value*) >
+<!ATTLIST enum id CDATA #REQUIRED >
+
+<!ELEMENT flags (value*) >
+<!ATTLIST flags id CDATA #REQUIRED >
+
+<!ELEMENT value EMPTY >
+<!-- nick must be at least 2 characters long -->
+<!-- value must be parsable as a 32-bit integer -->
+<!ATTLIST value nick CDATA #REQUIRED
+ value CDATA #REQUIRED >
+
+<!ELEMENT key (default|summary?|description?|range?|choices?|aliases?)* >