-- | null (tyConDataCons tcon) = error "MkExternalCore died: can't handle datatype declarations with no data constructors"
| otherwise =
C.Data (make_con_qid (tyConName tcon)) (map make_tbind tyvars) (map make_cdef (tyConDataCons tcon))
- where repclause | isRecursiveTyCon tcon = Nothing
+ where repclause | isRecursiveTyCon tcon || isOpenTyCon tcon= Nothing
| otherwise = Just (make_ty rep)
where (_, rep) = newTyConRep tcon
tyvars = tyConTyVars tcon