-(* Copyright (C) 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/.
- *)
-
-module Codomain = struct
- type t = Cic.term
- let compare = Pervasives.compare
-end
-module S = Set.Make(Codomain)
-module TI = Discrimination_tree.Make(Cic_indexable.CicIndexable)(S)
-type universe = TI.t
-
-let empty = TI.empty ;;
-
-let iter u f =
- TI.iter u
- (fun p s -> f p (S.elements s))
-;;
-
-let get_candidates univ ty =
- S.elements (TI.retrieve_unifiables univ ty)
-;;
-
-let in_universe univ ty =
- let candidates = get_candidates univ ty in
- List.fold_left
- (fun res cand ->
- match res with
- | Some found -> Some found
- | None ->
- let candty,_ =
- CicTypeChecker.type_of_aux' [] [] cand CicUniv.oblivion_ugraph in
- let same ,_ =
- CicReduction.are_convertible [] candty ty CicUniv.oblivion_ugraph in
- if same then Some cand else None
- ) None candidates
-;;
-
-let rec unfold context = function
- | Cic.Prod(name,s,t) ->
- let t' = unfold ((Some (name,Cic.Decl s))::context) t in
- Cic.Prod(name,s,t')
- | t -> ProofEngineReduction.unfold context t
-
-let rec collapse_head_metas t =
- match t with
- | Cic.Appl([]) -> assert false
- | Cic.Appl(a::l) ->
- let a' = collapse_head_metas a in
- (match a' with
- | Cic.Meta(n,m) -> Cic.Meta(n,m)
- | t ->
- let l' = List.map collapse_head_metas l in
- Cic.Appl(t::l'))
- | Cic.Rel _
- | Cic.Var _
- | Cic.Meta _
- | Cic.Sort _
- | Cic.Implicit _
- | Cic.Const _
- | Cic.MutInd _
- | Cic.MutConstruct _ -> t
- | Cic.LetIn _
- | Cic.Lambda _
- | Cic.Prod _
- | Cic.Cast _
- | Cic.MutCase _
- | Cic.Fix _
- | Cic.CoFix _ -> Cic.Meta(-1,[])
-;;
-
-let rec dummies_of_coercions =
- function
- | Cic.Appl (c::l) when CoercDb.is_a_coercion c <> None ->
- Cic.Meta (-1,[])
- | Cic.Appl l ->
- let l' = List.map dummies_of_coercions l in Cic.Appl l'
- | Cic.Lambda(n,s,t) ->
- let s' = dummies_of_coercions s in
- let t' = dummies_of_coercions t in
- Cic.Lambda (n,s',t')
- | Cic.Prod(n,s,t) ->
- let s' = dummies_of_coercions s in
- let t' = dummies_of_coercions t in
- Cic.Prod (n,s',t')
- | Cic.LetIn(n,s,ty,t) ->
- let s' = dummies_of_coercions s in
- let ty' = dummies_of_coercions ty in
- let t' = dummies_of_coercions t in
- Cic.LetIn (n,s',ty',t')
- | Cic.MutCase _ -> Cic.Meta (-1,[])
- | t -> t
-;;
-
-
-let rec head remove_coercions t =
- let clean_up t =
- if remove_coercions then dummies_of_coercions t
- else t in
- let rec aux = function
- | Cic.Prod(_,_,t) ->
- CicSubstitution.subst (Cic.Meta (-1,[])) (aux t)
- | t -> t
- in collapse_head_metas (clean_up (aux t))
-;;
-
-
-let index univ key term =
- (* flexible terms are not indexed *)
- if key = Cic.Meta(-1,[]) then univ
- else
- ((*prerr_endline("ADD: "^CicPp.ppterm key^" |-> "^CicPp.ppterm term);*)
- TI.index univ key term)
-;;
-
-let keys context ty =
- try
- [head true ty; head true (unfold context ty)]
- with ProofEngineTypes.Fail _ -> [head true ty]
-
-let key term = head false term;;
-
-let index_term_and_unfolded_term univ context t ty =
- let key = head true ty in
- let univ = index univ key t in
- try
- let key = head true (unfold context ty) in
- index univ key t
- with ProofEngineTypes.Fail _ -> univ
-;;
-
-let index_local_term univ context t ty =
- let key = head true ty in
- let univ = index univ key t in
- let key1 = head false ty in
- let univ =
- if key<>key1 then index univ key1 t else univ in
- try
- let key = head true (unfold context ty) in
- index univ key t
- with ProofEngineTypes.Fail _ -> univ
-;;
-
-
-let index_list univ context terms_and_types =
- List.fold_left
- (fun acc (term,ty) ->
- index_term_and_unfolded_term acc context term ty)
- univ terms_and_types
-
-;;
-
-let remove univ context term ty =
- let key = head true ty in
- let univ = TI.remove_index univ key term in
- try
- let key = head true (unfold context ty) in
- TI.remove_index univ key term
- with ProofEngineTypes.Fail _ -> univ
-
-let remove_uri univ uri =
- let term = CicUtil.term_of_uri uri in
- let ty,_ = CicTypeChecker.type_of_aux' [] [] term CicUniv.oblivion_ugraph in
- remove univ [] term ty
-
-