+ let ty =
+ try NCicTypeChecker.typeof ~metasenv:[] ~subst:[] [] t
+ with NCicTypeChecker.TypeCheckerFailure s ->
+ prerr_endline ("illtyped coercion: "^Lazy.force s);
+ prerr_endline (NCicPp.ppterm ~metasenv:[] ~subst:[] ~context:[] t);
+ assert false
+ in