-- others:
import Var ( Id, TyVar )
import DataCon ( DataCon, dataConTyCon )
-import Name ( Name, isDataSymOcc, getOccName, NamedThing )
+import Name ( isDataSymOcc, getOccName, NamedThing )
import Maybes ( maybeToBool )
import Outputable
import TyCon ( maybeTyConSingleCon )