*)
val set_default : string -> UriManager.uri list -> unit
-val reset_defaults : unit -> unit
+val reset_defaults : unit -> unit
+val push: unit -> unit
+val pop: unit -> unit
val eq_URI : unit -> UriManager.uri option
val true_URI : unit -> UriManager.uri option
val absurd_URI : unit -> UriManager.uri option
-val build_nat : int -> Cic.term
+val nat_URI : unit -> UriManager.uri option
+val is_nat_URI : UriManager.uri -> bool