+(* Functions to be used by the refiner *)
+val debruijn:
+ NUri.uri -> int -> subst:NCic.substitution -> NCic.context -> NCic.term ->
+ NCic.term
+val are_all_occurrences_positive:
+ subst:NCic.substitution ->
+ NCic.context -> NUri.uri -> int -> int -> int -> int -> NCic.term -> bool