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(************************************************************************)
(*  v      *   The Coq Proof Assistant  /  The Coq Development Team     *)
(* <O___,, *   INRIA - CNRS - LIX - LRI - PPS - Copyright 1999-2015     *)
(*   \VV/  **************************************************************)
(*    //   *      This file is distributed under the terms of the       *)
(*         *       GNU Lesser General Public License Version 2.1        *)
(************************************************************************)

(*i camlp4deps: "grammar/grammar.cma" i*)

open Pp
open Errors
open Util
open Names
open Nameops
open Term
open Termops
open Proof_type
open Tacticals
open Tacmach
open Tactics
open Patternops
open Clenv
open Auto
open Genredexpr
open Tacexpr
open Misctypes
open Locus
open Locusops
open Hints
open Proofview.Notations

DECLARE PLUGIN "eauto"

let eauto_unif_flags = auto_flags_of_state full_transparent_state

let e_give_exact ?(flags=eauto_unif_flags) c =
  Proofview.Goal.nf_enter { enter = begin fun gl ->
  let t1 = Tacmach.New.pf_unsafe_type_of gl c in
  let t2 = Tacmach.New.pf_concl gl in
  if occur_existential t1 || occur_existential t2 then
     Tacticals.New.tclTHEN (Clenvtac.unify ~flags t1) (Proofview.V82.tactic (exact_no_check c))
  else exact_check c
  end }

let assumption id = e_give_exact (mkVar id)

let e_assumption =
  Proofview.Goal.enter { enter = begin fun gl ->
    Tacticals.New.tclFIRST (List.map assumption (Tacmach.New.pf_ids_of_hyps gl))
  end }

TACTIC EXTEND eassumption
| [ "eassumption" ] -> [ e_assumption ]
END

TACTIC EXTEND eexact
| [ "eexact" constr(c) ] -> [ e_give_exact c ]
END

let registered_e_assumption =
  Proofview.Goal.enter { enter = begin fun gl ->
  Tacticals.New.tclFIRST (List.map (fun id -> e_give_exact (mkVar id))
              (Tacmach.New.pf_ids_of_hyps gl))
  end }

let eval_uconstrs ist cs =
  let flags = {
    Pretyping.use_typeclasses = false;
    use_unif_heuristics = true;
    use_hook = Some Pfedit.solve_by_implicit_tactic;
    fail_evar = false;
    expand_evars = true
  } in
  List.map (fun c -> Tacinterp.type_uconstr ~flags ist c) cs

(************************************************************************)
(*   PROLOG tactic                                                      *)
(************************************************************************)

(*s Tactics handling a list of goals. *)

(* first_goal : goal list sigma -> goal sigma *)

let first_goal gls =
  let gl = gls.Evd.it and sig_0 = gls.Evd.sigma in
  if List.is_empty gl then error "first_goal";
  { Evd.it = List.hd gl; Evd.sigma = sig_0; }

(* tactic -> tactic_list : Apply a tactic to the first goal in the list *)

let apply_tac_list tac glls =
  let (sigr,lg) = unpackage glls in
  match lg with
  | (g1::rest) ->
      let gl = apply_sig_tac sigr tac g1 in
      repackage sigr (gl@rest)
  | _ -> error "apply_tac_list"

let one_step l gl =
  [Proofview.V82.of_tactic Tactics.intro]
  @ (List.map (fun c -> Proofview.V82.of_tactic (Tactics.Simple.eapply c)) (List.map mkVar (pf_ids_of_hyps gl)))
  @ (List.map (fun c -> Proofview.V82.of_tactic (Tactics.Simple.eapply c)) l)
  @ (List.map (fun c -> Proofview.V82.of_tactic (assumption c)) (pf_ids_of_hyps gl))

let rec prolog l n gl =
  if n <= 0 then error "prolog - failure";
  let prol = (prolog l (n-1)) in
  (tclFIRST (List.map (fun t -> (tclTHEN t prol)) (one_step l gl))) gl

let out_term = function
  | IsConstr (c, _) -> c
  | IsGlobRef gr -> fst (Universes.fresh_global_instance (Global.env ()) gr)

let prolog_tac l n gl =
  let map c =
    let (c, sigma) = Tactics.run_delayed (pf_env gl) (project gl) c in
    let c = pf_apply (prepare_hint false (false,true)) gl (sigma, c) in
    out_term c
  in
  let l = List.map map l in
  try (prolog l n gl)
  with UserError ("Refiner.tclFIRST",_) ->
    errorlabstrm "Prolog.prolog" (str "Prolog failed.")

TACTIC EXTEND prolog
| [ "prolog" "[" uconstr_list(l) "]" int_or_var(n) ] ->
    [ Proofview.V82.tactic (prolog_tac (eval_uconstrs ist l) n) ]
END

open Auto
open Unification

(***************************************************************************)
(* A tactic similar to Auto, but using EApply, Assumption and e_give_exact *)
(***************************************************************************)

let priority l = List.map snd (List.filter (fun (pr,_) -> Int.equal pr 0) l)
			  
let unify_e_resolve poly flags (c,clenv) =
  Proofview.Goal.nf_enter { enter = begin fun gl ->
      let clenv', c = connect_hint_clenv poly c clenv gl in
      Proofview.V82.tactic
	(fun gls ->
	 let clenv' = clenv_unique_resolver ~flags clenv' gls in
	 tclTHEN (Refiner.tclEVARUNIVCONTEXT (Evd.evar_universe_context clenv'.evd))
		 (Proofview.V82.of_tactic (Tactics.Simple.eapply c)) gls)
    end }

let hintmap_of hdc concl =
  match hdc with
  | None -> fun db -> Hint_db.map_none db
  | Some hdc ->
    if occur_existential concl then (fun db -> Hint_db.map_existential hdc concl db)
    else (fun db -> Hint_db.map_auto hdc concl db)
   (* FIXME: should be (Hint_db.map_eauto hdc concl db) *)

let e_exact poly flags (c,clenv) =
  let (c, _, _) = c in
  let clenv', subst = 
    if poly then Clenv.refresh_undefined_univs clenv 
    else clenv, Univ.empty_level_subst
  in e_give_exact (* ~flags *) (Vars.subst_univs_level_constr subst c)

let rec e_trivial_fail_db db_list local_db =
  let next = Proofview.Goal.nf_enter { enter = begin fun gl ->
    let d = Tacmach.New.pf_last_hyp gl in
    let hintl = make_resolve_hyp (Tacmach.New.pf_env gl) (Tacmach.New.project gl) d in
    e_trivial_fail_db db_list (Hint_db.add_list (Tacmach.New.pf_env gl) (Tacmach.New.project gl) hintl local_db)
  end } in
  Proofview.Goal.enter { enter = begin fun gl ->
  let tacl =
    registered_e_assumption ::
    (Tacticals.New.tclTHEN Tactics.intro next) ::
    (List.map fst (e_trivial_resolve db_list local_db (Tacmach.New.pf_nf_concl gl)))
  in
  Tacticals.New.tclFIRST (List.map Tacticals.New.tclCOMPLETE tacl)
  end }

and e_my_find_search db_list local_db hdc concl =
  let hint_of_db = hintmap_of hdc concl in
  let hintl =
      List.map_append (fun db ->
	let flags = auto_flags_of_state (Hint_db.transparent_state db) in
	  List.map (fun x -> flags, x) (hint_of_db db)) (local_db::db_list)
  in
  let tac_of_hint =
    fun (st, {pri = b; pat = p; code = t; poly = poly}) ->
      let b = match Hints.repr_hint t with
      | Unfold_nth _ -> 1
      | _ -> b
      in
      (b,
        let tac = function
        | Res_pf (term,cl) -> unify_resolve poly st (term,cl)
        | ERes_pf (term,cl) -> unify_e_resolve poly st (term,cl)
        | Give_exact (c,cl) -> e_exact poly st (c,cl)
        | Res_pf_THEN_trivial_fail (term,cl) ->
          Tacticals.New.tclTHEN (unify_e_resolve poly st (term,cl))
            (e_trivial_fail_db db_list local_db)
        | Unfold_nth c -> Proofview.V82.tactic (reduce (Unfold [AllOccurrences,c]) onConcl)
        | Extern tacast -> conclPattern concl p tacast
       in
       let tac = run_hint t tac in
       (tac, lazy (pr_hint t)))
  in
  List.map tac_of_hint hintl

and e_trivial_resolve db_list local_db gl =
  let hd = try Some (decompose_app_bound gl) with Bound -> None in
  try priority (e_my_find_search db_list local_db hd gl)
  with Not_found -> []

let e_possible_resolve db_list local_db gl =
  let hd = try Some (decompose_app_bound gl) with Bound -> None in
  try List.map (fun (b, (tac, pp)) -> (tac, b, pp)) (e_my_find_search db_list local_db hd gl)
  with Not_found -> []

let find_first_goal gls =
  try first_goal gls with UserError _ -> assert false

(*s The following module [SearchProblem] is used to instantiate the generic
    exploration functor [Explore.Make]. *)

type search_state = {
  priority : int;
  depth : int; (*r depth of search before failing *)
  tacres : goal list sigma;
  last_tactic : std_ppcmds Lazy.t;
  dblist : hint_db list;
  localdb :  hint_db list;
  prev : prev_search_state;
  local_lemmas : Tacexpr.delayed_open_constr list;
}

and prev_search_state = (* for info eauto *)
  | Unknown
  | Init
  | State of search_state

module SearchProblem = struct

  type state = search_state

  let success s = List.is_empty (sig_it s.tacres)

(*   let pr_ev evs ev = Printer.pr_constr_env (Evd.evar_env ev) (Evarutil.nf_evar evs ev.Evd.evar_concl) *)

  let filter_tactics glls l =
(*     let _ = Proof_trees.db_pr_goal (List.hd (sig_it glls)) in *)
(*     let evars = Evarutil.nf_evars (Refiner.project glls) in *)
(*     msg (str"Goal:" ++ pr_ev evars (List.hd (sig_it glls)) ++ str"\n"); *)
    let rec aux = function
      | [] -> []
      | (tac, cost, pptac) :: tacl ->
	  try
	    let lgls = apply_tac_list (Proofview.V82.of_tactic tac) glls in
(* 	    let gl = Proof_trees.db_pr_goal (List.hd (sig_it glls)) in *)
(* 	      msg (hov 1 (pptac ++ str" gives: \n" ++ pr_goals lgls ++ str"\n")); *)
	      (lgls, cost, pptac) :: aux tacl
	  with e when Errors.noncritical e ->
            let e = Errors.push e in
            Refiner.catch_failerror e; aux tacl
    in aux l

  (* Ordering of states is lexicographic on depth (greatest first) then
     number of remaining goals. *)
  let compare s s' =
    let d = s'.depth - s.depth in
    let d' = Int.compare s.priority s'.priority in
    let nbgoals s = List.length (sig_it s.tacres) in
    if not (Int.equal d 0) then d
    else if not (Int.equal d' 0) then d'
    else Int.compare (nbgoals s) (nbgoals s')

  let branching s =
    if Int.equal s.depth 0 then
      []
    else
      let ps = if s.prev == Unknown then Unknown else State s in
      let lg = s.tacres in
      let nbgl = List.length (sig_it lg) in
      assert (nbgl > 0);
      let g = find_first_goal lg in
      let map_assum id = (e_give_exact (mkVar id), (-1), lazy (str "exact" ++ spc () ++ pr_id id)) in
      let assumption_tacs =
        let tacs = List.map map_assum (pf_ids_of_hyps g) in
        let l = filter_tactics s.tacres tacs in
	List.map (fun (res, cost, pp) -> { depth = s.depth; priority = cost; tacres = res;
				    last_tactic = pp; dblist = s.dblist;
				    localdb = List.tl s.localdb;
				    prev = ps; local_lemmas = s.local_lemmas}) l
      in
      let intro_tac =
        let l = filter_tactics s.tacres [Tactics.intro, (-1), lazy (str "intro")] in
	List.map
	  (fun (lgls, cost, pp) ->
	     let g' = first_goal lgls in
	     let hintl =
	       make_resolve_hyp (pf_env g') (project g') (pf_last_hyp g')
	     in
             let ldb = Hint_db.add_list (pf_env g') (project g')
		  hintl (List.hd s.localdb) in
	     { depth = s.depth; priority = cost; tacres = lgls;
	       last_tactic = pp; dblist = s.dblist;
	       localdb = ldb :: List.tl s.localdb; prev = ps;
               local_lemmas = s.local_lemmas})
	  l
      in
      let rec_tacs =
	let l =
	  filter_tactics s.tacres (e_possible_resolve s.dblist (List.hd s.localdb) (pf_concl g))
	in
	List.map
	  (fun (lgls, cost, pp) ->
	     let nbgl' = List.length (sig_it lgls) in
	     if nbgl' < nbgl then
	       { depth = s.depth; priority = cost; tacres = lgls; last_tactic = pp;
                  prev = ps; dblist = s.dblist; localdb = List.tl s.localdb;
                  local_lemmas = s.local_lemmas }
	     else
	       let newlocal = 
		 let hyps = pf_hyps g in
		   List.map (fun gl ->
		     let gls = {Evd.it = gl; sigma = lgls.Evd.sigma } in
		     let hyps' = pf_hyps gls in
		       if hyps' == hyps then List.hd s.localdb
		       else make_local_hint_db (pf_env gls) (project gls) ~ts:full_transparent_state true s.local_lemmas)
		     (List.firstn ((nbgl'-nbgl) + 1) (sig_it lgls))
	       in
		 { depth = pred s.depth; priority = cost; tacres = lgls;
		   dblist = s.dblist; last_tactic = pp; prev = ps;
		   localdb = newlocal @ List.tl s.localdb;
                   local_lemmas = s.local_lemmas })
	  l
      in
      List.sort compare (assumption_tacs @ intro_tac @ rec_tacs)

  let pp s = hov 0 (str " depth=" ++ int s.depth ++ spc () ++
		      (Lazy.force s.last_tactic))

end

module Search = Explore.Make(SearchProblem)

(** Utilities for debug eauto / info eauto *)

let global_debug_eauto = ref false
let global_info_eauto = ref false

let _ =
  Goptions.declare_bool_option
    { Goptions.optsync  = true;
      Goptions.optdepr  = false;
      Goptions.optname  = "Debug Eauto";
      Goptions.optkey   = ["Debug";"Eauto"];
      Goptions.optread  = (fun () -> !global_debug_eauto);
      Goptions.optwrite = (:=) global_debug_eauto }

let _ =
  Goptions.declare_bool_option
    { Goptions.optsync  = true;
      Goptions.optdepr  = false;
      Goptions.optname  = "Info Eauto";
      Goptions.optkey   = ["Info";"Eauto"];
      Goptions.optread  = (fun () -> !global_info_eauto);
      Goptions.optwrite = (:=) global_info_eauto }

let mk_eauto_dbg d =
  if d == Debug || !global_debug_eauto then Debug
  else if d == Info || !global_info_eauto then Info
  else Off

let pr_info_nop = function
  | Info -> msg_debug (str "idtac.")
  | _ -> ()

let pr_dbg_header = function
  | Off -> ()
  | Debug -> msg_debug (str "(* debug eauto : *)")
  | Info -> msg_debug (str "(* info eauto : *)")

let pr_info dbg s =
  if dbg != Info then ()
  else
    let rec loop s =
      match s.prev with
	| Unknown | Init -> s.depth
	| State sp ->
	  let mindepth = loop sp in
	  let indent = String.make (mindepth - sp.depth) ' ' in
	  msg_debug (str indent ++ Lazy.force s.last_tactic ++ str ".");
	  mindepth
    in
    ignore (loop s)

(** Eauto main code *)

let make_initial_state dbg n gl dblist localdb lems =
  { depth = n;
    priority = 0;
    tacres = tclIDTAC gl;
    last_tactic = lazy (mt());
    dblist = dblist;
    localdb = [localdb];
    prev = if dbg == Info then Init else Unknown;
    local_lemmas = lems;
  }

let e_search_auto debug (in_depth,p) lems db_list gl =
  let local_db = make_local_hint_db (pf_env gl) (project gl) ~ts:full_transparent_state true lems in
  let d = mk_eauto_dbg debug in
  let tac = match in_depth,d with
    | (true,Debug) -> Search.debug_depth_first
    | (true,_) -> Search.depth_first
    | (false,Debug) -> Search.debug_breadth_first
    | (false,_) -> Search.breadth_first
  in
  try
    pr_dbg_header d;
    let s = tac (make_initial_state d p gl db_list local_db lems) in
    pr_info d s;
    s.tacres
  with Not_found ->
    pr_info_nop d;
    error "eauto: search failed"

(* let e_search_auto_key = Profile.declare_profile "e_search_auto" *)
(* let e_search_auto = Profile.profile5 e_search_auto_key e_search_auto *)

let eauto_with_bases ?(debug=Off) np lems db_list =
  tclTRY (e_search_auto debug np lems db_list)

let eauto ?(debug=Off) np lems dbnames =
  let db_list = make_db_list dbnames in
  tclTRY (e_search_auto debug np lems db_list)

let full_eauto ?(debug=Off) n lems gl =
  let dbnames = current_db_names () in
  let dbnames =  String.Set.remove "v62" dbnames in
  let db_list = List.map searchtable_map (String.Set.elements dbnames) in
  tclTRY (e_search_auto debug n lems db_list) gl

let gen_eauto ?(debug=Off) np lems = function
  | None -> full_eauto ~debug np lems
  | Some l -> eauto ~debug np lems l

let make_depth = function
  | None -> !default_search_depth
  | Some d -> d

let make_dimension n = function
  | None -> (true,make_depth n)
  | Some d -> (false,d)

open Genarg
open G_auto

let hintbases = G_auto.hintbases
let wit_hintbases = G_auto.wit_hintbases

TACTIC EXTEND eauto
| [ "eauto" int_or_var_opt(n) int_or_var_opt(p) auto_using(lems)
    hintbases(db) ] ->
    [ Proofview.V82.tactic (gen_eauto (make_dimension n p) (eval_uconstrs ist lems) db) ]
END

TACTIC EXTEND new_eauto
| [ "new" "auto" int_or_var_opt(n) auto_using(lems)
    hintbases(db) ] ->
    [ match db with
      | None -> new_full_auto (make_depth n) (eval_uconstrs ist lems)
      | Some l -> new_auto (make_depth n) (eval_uconstrs ist lems) l ]
END

TACTIC EXTEND debug_eauto
| [ "debug" "eauto" int_or_var_opt(n) int_or_var_opt(p) auto_using(lems)
    hintbases(db) ] ->
    [ Proofview.V82.tactic (gen_eauto ~debug:Debug (make_dimension n p) (eval_uconstrs ist lems) db) ]
END

TACTIC EXTEND info_eauto
| [ "info_eauto" int_or_var_opt(n) int_or_var_opt(p) auto_using(lems)
    hintbases(db) ] ->
    [ Proofview.V82.tactic (gen_eauto ~debug:Info (make_dimension n p) (eval_uconstrs ist lems) db) ]
END

TACTIC EXTEND dfs_eauto
| [ "dfs" "eauto" int_or_var_opt(p) auto_using(lems)
      hintbases(db) ] ->
    [ Proofview.V82.tactic (gen_eauto (true, make_depth p) (eval_uconstrs ist lems) db) ]
END

let cons a l = a :: l

let autounfolds db occs cls gl =
  let unfolds = List.concat (List.map (fun dbname -> 
    let db = try searchtable_map dbname 
      with Not_found -> errorlabstrm "autounfold" (str "Unknown database " ++ str dbname)
    in
    let (ids, csts) = Hint_db.unfolds db in
    let hyps = pf_ids_of_hyps gl in
    let ids = Idset.filter (fun id -> List.mem id hyps) ids in
      Cset.fold (fun cst -> cons (AllOccurrences, EvalConstRef cst)) csts
	(Id.Set.fold (fun id -> cons (AllOccurrences, EvalVarRef id)) ids [])) db)
  in unfold_option unfolds cls gl

let autounfold db cls gl =
  let cls = concrete_clause_of (fun () -> pf_ids_of_hyps gl) cls in
  let tac = autounfolds db in
  tclMAP (function
    | OnHyp (id,occs,where) -> tac occs (Some (id,where))
    | OnConcl occs -> tac occs None)
    cls gl

let autounfold_tac db cls gl =
  let dbs = match db with
  | None -> String.Set.elements (current_db_names ())
  | Some [] -> ["core"]
  | Some l -> l
  in
  autounfold dbs  cls gl

TACTIC EXTEND autounfold
| [ "autounfold" hintbases(db) clause(cl) ] -> [ Proofview.V82.tactic (autounfold_tac db cl) ]
END

let unfold_head env (ids, csts) c = 
  let rec aux c = 
    match kind_of_term c with
    | Var id when Id.Set.mem id ids ->
	(match Environ.named_body id env with
	| Some b -> true, b
	| None -> false, c)
    | Const (cst,u as c) when Cset.mem cst csts ->
	true, Environ.constant_value_in env c
    | App (f, args) ->
	(match aux f with
	| true, f' -> true, Reductionops.whd_betaiota Evd.empty (mkApp (f', args))
	| false, _ -> 
	    let done_, args' = 
	      Array.fold_left_i (fun i (done_, acc) arg -> 
		if done_ then done_, arg :: acc 
		else match aux arg with
		| true, arg' -> true, arg' :: acc
		| false, arg' -> false, arg :: acc)
		(false, []) args
	    in 
	      if done_ then true, mkApp (f, Array.of_list (List.rev args'))
	      else false, c)
    | _ -> 
	let done_ = ref false in
	let c' = map_constr (fun c -> 
	  if !done_ then c else 
	    let x, c' = aux c in
	      done_ := x; c') c
	in !done_, c'
  in aux c

let autounfold_one db cl =
  Proofview.Goal.nf_enter { enter = begin fun gl ->
  let env = Proofview.Goal.env gl in
  let concl = Proofview.Goal.concl gl in
  let st =
    List.fold_left (fun (i,c) dbname -> 
      let db = try searchtable_map dbname 
	with Not_found -> errorlabstrm "autounfold" (str "Unknown database " ++ str dbname)
      in
      let (ids, csts) = Hint_db.unfolds db in
	(Id.Set.union ids i, Cset.union csts c)) (Id.Set.empty, Cset.empty) db
  in
  let did, c' = unfold_head env st 
    (match cl with Some (id, _) -> Tacmach.New.pf_get_hyp_typ id gl | None -> concl) 
  in
    if did then
      match cl with
      | Some hyp -> change_in_hyp None (make_change_arg c') hyp
      | None -> convert_concl_no_check c' DEFAULTcast
    else Tacticals.New.tclFAIL 0 (str "Nothing to unfold")
  end }

(* 	  Cset.fold (fun cst -> cons (all_occurrences, EvalConstRef cst)) csts *)
(* 	    (Id.Set.fold (fun id -> cons (all_occurrences, EvalVarRef id)) ids [])) db) *)
(*       in unfold_option unfolds cl *)

(*       let db = try searchtable_map dbname  *)
(* 	with Not_found -> errorlabstrm "autounfold" (str "Unknown database " ++ str dbname) *)
(*       in *)
(*       let (ids, csts) = Hint_db.unfolds db in *)
(* 	Cset.fold (fun cst -> tclORELSE (unfold_option [(occ, EvalVarRef id)] cst)) csts *)
(* 	  (Id.Set.fold (fun id -> tclORELSE (unfold_option [(occ, EvalVarRef id)] cl) ids acc))) *)
(*       (tclFAIL 0 (mt())) db *)
      
TACTIC EXTEND autounfold_one
| [ "autounfold_one" hintbases(db) "in" hyp(id) ] ->
    [ autounfold_one (match db with None -> ["core"] | Some x -> "core"::x) (Some (id, InHyp)) ]
| [ "autounfold_one" hintbases(db) ] ->
    [ autounfold_one (match db with None -> ["core"] | Some x -> "core"::x) None ]
      END

TACTIC EXTEND autounfoldify
| [ "autounfoldify" constr(x) ] -> [
  Proofview.V82.tactic (
    let db = match kind_of_term x with
      | Const (c,_) -> Label.to_string (con_label c)
      | _ -> assert false
    in autounfold ["core";db] onConcl 
  )]
END

TACTIC EXTEND unify
| ["unify" constr(x) constr(y) ] -> [ unify x y ]
| ["unify" constr(x) constr(y) "with" preident(base)  ] -> [
    let table = try Some (searchtable_map base) with Not_found -> None in
    match table with
    | None ->
      let msg = str "Hint table " ++ str base ++ str " not found" in
      Tacticals.New.tclZEROMSG msg
    | Some t ->
      let state = Hint_db.transparent_state t in
      unify ~state x y
  ]
END


TACTIC EXTEND convert_concl_no_check
| ["convert_concl_no_check" constr(x) ] -> [ convert_concl_no_check x DEFAULTcast ]
END

let pr_hints_path_atom _ _ _ = Hints.pp_hints_path_atom

ARGUMENT EXTEND hints_path_atom
  TYPED AS hints_path_atom
  PRINTED BY pr_hints_path_atom
| [ global_list(g) ] -> [ PathHints (List.map Nametab.global g) ]
| [ "*" ] -> [ PathAny ]
END

let pr_hints_path prc prx pry c = Hints.pp_hints_path c

ARGUMENT EXTEND hints_path
  TYPED AS hints_path
  PRINTED BY pr_hints_path
| [ "(" hints_path(p) ")"  ] -> [ p ]
| [ "!" hints_path(p)  ] -> [ PathStar p ]
| [ "emp" ] -> [ PathEmpty ]
| [ "eps" ] -> [ PathEpsilon ]
| [ hints_path_atom(a) ] -> [ PathAtom a ]
| [ hints_path(p) "|" hints_path(q) ] -> [ PathOr (p, q) ]
| [ hints_path(p) ";" hints_path(q) ] -> [ PathSeq (p, q) ]
END

let pr_hintbases _prc _prlc _prt = Pptactic.pr_hintbases

ARGUMENT EXTEND opthints
  TYPED AS preident_list_opt
  PRINTED BY pr_hintbases
| [ ":" ne_preident_list(l) ] -> [ Some l ]
| [ ] -> [ None ]
END

VERNAC COMMAND EXTEND HintCut CLASSIFIED AS SIDEFF
| [ "Hint" "Cut" "[" hints_path(p) "]" opthints(dbnames) ] -> [
  let entry = HintsCutEntry p in
    Hints.add_hints (Locality.make_section_locality (Locality.LocalityFixme.consume ()))
      (match dbnames with None -> ["core"] | Some l -> l) entry ]
END