(* Copyright (C) 2000-2002, HELM Team.
 * 
 * This file is part of HELM, an Hypertextual, Electronic
 * Library of Mathematics, developed at the Computer Science
 * Department, University of Bologna, Italy.
 * 
 * HELM is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 * 
 * HELM is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with HELM; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston,
 * MA  02111-1307, USA.
 * 
 * For details, see the HELM World-Wide-Web page,
 * http://cs.unibo.it/helm/.
 *)

exception Bad_pattern of string Lazy.t

(* Returns the first meta whose number is above the *)
(* number of the higher meta.                       *)
val new_meta_of_proof : proof:ProofEngineTypes.proof -> int

val subst_meta_in_proof :
  ProofEngineTypes.proof ->
  int -> Cic.term -> Cic.metasenv ->
  ProofEngineTypes.proof * Cic.metasenv
val subst_meta_and_metasenv_in_proof :
  ProofEngineTypes.proof ->
  int -> (Cic.term -> Cic.term) -> Cic.metasenv ->
  ProofEngineTypes.proof * Cic.metasenv

(* returns the list of goals that are in newmetasenv and were not in
   oldmetasenv *)
val compare_metasenvs :
  oldmetasenv:Cic.metasenv -> newmetasenv:Cic.metasenv -> int list


(** { Patterns }
 * A pattern is a Cic term in which Cic.Implicit terms annotated with `Hole
 * appears *)

(** create a pattern from a term and a list of subterms.
* the pattern is granted to have a ? for every subterm that has no selected
* subterms
* @param equality equality function used while walking the term. Defaults to
* physical equality (==) *)
val pattern_of:
 ?equality:(Cic.term -> Cic.term -> bool) -> term:Cic.term -> Cic.term list ->
   Cic.term


(** select metasenv conjecture pattern
* select all subterms of [conjecture] matching [pattern].
* It returns the set of matched terms (that can be compared using physical
* equality to the subterms of [conjecture]) together with their contexts.
* The representation of the set mimics the conjecture type (but for the id):
* a list of (possibly removed) hypothesis (without their names) together with
* the list of its matched subterms (and their contexts) + the list of matched
* subterms of the conclusion with their context. Note: in the result the list
* of hypotheses * has an entry for each entry in the context and in the same
* order. Of course the list of terms (with their context) associated to one
* hypothesis may be empty. 
*
* @raise Bad_pattern
* *)
val select:
 metasenv:Cic.metasenv ->
 ugraph:CicUniv.universe_graph ->
 conjecture:Cic.conjecture ->
 pattern:ProofEngineTypes.pattern ->
  Cic.substitution * Cic.metasenv * CicUniv.universe_graph *
  [ `Decl of (Cic.context * Cic.term) list
  | `Def of (Cic.context * Cic.term) list * (Cic.context * Cic.term) list option
  ] option list *
  (Cic.context * Cic.term) list

(** locate_in_term equality what where context
* [what] must match a subterm of [where] according to [equality]
* It returns the matched terms together with their contexts in [where]
* [equality] defaults to physical equality
* [context] must be the context of [where]
*)
val locate_in_term:
 ?equality:(Cic.context -> Cic.term -> Cic.term -> bool) ->
  Cic.term -> where:Cic.term -> Cic.context -> (Cic.context * Cic.term) list

(** locate_in_conjecture equality what where context
* [what] must match a subterm of [where] according to [equality]
* It returns the matched terms together with their contexts in [where]
* [equality] defaults to physical equality
* [context] must be the context of [where]
*)
val locate_in_conjecture:
 ?equality:(Cic.context -> Cic.term -> Cic.term -> bool) ->
  Cic.term -> Cic.conjecture -> (Cic.context * Cic.term) list

(* saturate_term newmeta metasenv context ty goal_arity                       *)
(* Given a type [ty] (a backbone), it returns its suffix of length            *)
(* [goal_arity] head and a new metasenv in which there is new a META for each *)
(* hypothesis, a list of arguments for the new applications and the index of  *)
(* the last new META introduced. The nth argument in the list of arguments is *)
(* just the nth new META.                                                     *)
val saturate_term:
 int -> Cic.metasenv -> Cic.context -> Cic.term -> int ->
  Cic.term * Cic.metasenv * Cic.term list * int

(* returns the index and the type of a premise in a context *)
val lookup_type: Cic.metasenv -> Cic.context -> string -> int * Cic.term