val string_of_reference: reference -> string
val reference_of_string: string -> reference
(* given the reference of an inductive type, returns the i-th contructor *)
val mk_constructor: int -> reference -> reference
val string_of_reference: reference -> string
val reference_of_string: string -> reference
(* given the reference of an inductive type, returns the i-th contructor *)
val mk_constructor: int -> reference -> reference