+(*
+type sequents_metadata =
+ (int * (** sequent (meta) index *)
+ (Cic.annconjecture * (** annotated conjecture *)
+ (Cic.id, Cic.term) Hashtbl.t * (** ids_to_terms *)
+ (Cic.id, Cic.id option) Hashtbl.t * (** ids_to_father_ids *)
+ (Cic.id, string) Hashtbl.t * (** ids_to_inner_sorts *)
+ (Cic.id, Cic.hypothesis) Hashtbl.t)) (** ids_to_hypotheses *)
+ list
+type proof_metadata =
+ Cic.annobj * (** annotated object *)
+ (Cic.id, Cic.term) Hashtbl.t * (** ids_to_terms *)
+ (Cic.id, Cic.id option) Hashtbl.t * (** ids_to_father_ids *)
+ (Cic.id, string) Hashtbl.t * (** ids_to_inner_sorts *)
+ (Cic.id, Cic2acic.anntypes) Hashtbl.t * (** ids_to_inner_types *)
+ (Cic.id, Cic.conjecture) Hashtbl.t * (** ids_to_conjectures *)
+ (Cic.id, Cic.hypothesis) Hashtbl.t (** ids_to_hypotheses *)
+type hist_metadata = proof_metadata * sequents_metadata
+*)
+
+class type proof =
+ object
+ inherit [unit] StatefulProofEngine.status
+
+ (** return a pair of "xml" (as defined in Xml module) representing the *
+ * current proof type and body, respectively *)
+ method toXml: Xml.token Stream.t * Xml.token Stream.t
+ method toString: string
+ end
+
+type proof_handler =
+ { get_proof: unit -> proof; (* return current proof or fail *)
+ set_proof: proof option -> unit;
+ abort_proof: unit -> unit;(* abort current proof, cleaning up garbage *)
+ has_proof: unit -> bool; (* check if a current proof is available or not *)
+ new_proof: proof -> unit; (* as a set_proof but takes care also to register
+ observers *)
+ quit: unit -> unit
+ }
+
+ (** interpreter for toplevel phrases given via console *)
+class type interpreter =