* http://helm.cs.unibo.it/
*)
+type 'a expected_type = [ `XTNone (* unknown *)
+ | `XTSome of 'a (* the given term *)
+ | `XTSort (* any sort *)
+ | `XTInd (* any (co)inductive type *)
+ ]
+
type domain_item =
| Id of string (* literal *)
| Symbol of string * int (* literal, instance num *)