X-Git-Url: http://matita.cs.unibo.it/gitweb/?p=helm.git;a=blobdiff_plain;f=components%2Fcic%2Fdiscrimination_tree.ml;fp=components%2Fcic%2Fdiscrimination_tree.ml;h=546f4a34fce9f01b2fcca86ff0148af5ee6ee045;hp=0000000000000000000000000000000000000000;hb=f61af501fb4608cc4fb062a0864c774e677f0d76;hpb=58ae1809c352e71e7b5530dc41e2bfc834e1aef1 diff --git a/components/cic/discrimination_tree.ml b/components/cic/discrimination_tree.ml new file mode 100644 index 000000000..546f4a34f --- /dev/null +++ b/components/cic/discrimination_tree.ml @@ -0,0 +1,305 @@ +(* Copyright (C) 2005, 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/. + *) + +(* $Id$ *) + +module DiscriminationTreeIndexing = + functor (A:Set.S) -> + struct + + type path_string_elem = + | Constant of UriManager.uri + | Bound of int | Variable | Proposition | Datatype | Dead;; + type path_string = path_string_elem list;; + + + (* needed by the retrieve_* functions, to know the arities of the + * "functions" *) + + let ppelem = function + | Constant uri -> UriManager.name_of_uri uri + | Bound i -> string_of_int i + | Variable -> "?" + | Proposition -> "Prop" + | Datatype -> "Type" + | Dead -> "DEAD" + ;; + let pppath l = String.concat "::" (List.map ppelem l) ;; + let elem_of_cic = function + | Cic.Meta _ | Cic.Implicit _ -> Variable + | Cic.Rel i -> Bound i + | Cic.Sort (Cic.Prop) -> Proposition + | Cic.Sort _ -> Datatype + | Cic.Const _ | Cic.Var _ | Cic.MutInd _ | Cic.MutConstruct _ as t -> + (try Constant (CicUtil.uri_of_term t) + with Invalid_argument _ -> assert false) + | Cic.Appl _ -> + assert false (* should not happen *) + | Cic.LetIn _ | Cic.Lambda _ | Cic.Prod _ | Cic.Cast _ + | Cic.MutCase _ | Cic.Fix _ | Cic.CoFix _ -> + HLog.debug "FIXME: the trie receives an invalid term"; + Dead + (* assert false universe.ml removes these *) + ;; + let path_string_of_term arities = + let set_arity arities k n = + (assert (k<>Variable || n=0); + if k = Dead then arities else (k,n)::(List.remove_assoc k arities)) + in + let rec aux arities = function + | Cic.Appl ((hd::tl) as l) -> + let arities = + set_arity arities (elem_of_cic hd) (List.length tl) in + List.fold_left + (fun (arities,path) t -> + let arities,tpath = aux arities t in + arities,path@tpath) + (arities,[]) l + | t -> arities, [elem_of_cic t] + in + aux arities + ;; + let compare_elem e1 e2 = + match e1,e2 with + | Constant u1,Constant u2 -> UriManager.compare u1 u2 + | e1,e2 -> Pervasives.compare e1 e2 + ;; + + module OrderedPathStringElement = struct + type t = path_string_elem + let compare = compare_elem + end + + module PSMap = Map.Make(OrderedPathStringElement);; + + type key = PSMap.key + + module DiscriminationTree = Trie.Make(PSMap);; + + type t = A.t DiscriminationTree.t * (path_string_elem*int) list + let empty = DiscriminationTree.empty, [] ;; + + let index (tree,arity) term info = + let arity,ps = path_string_of_term arity term in + let ps_set = + try DiscriminationTree.find ps tree + with Not_found -> A.empty in + let tree = DiscriminationTree.add ps (A.add info ps_set) tree in + tree,arity + ;; + + let remove_index (tree,arity) term info = + let arity,ps = path_string_of_term arity term in + try + let ps_set = A.remove info (DiscriminationTree.find ps tree) in + if A.is_empty ps_set then + DiscriminationTree.remove ps tree,arity + else + DiscriminationTree.add ps ps_set tree,arity + with Not_found -> + tree,arity + ;; + + let in_index (tree,arity) term test = + let arity,ps = path_string_of_term arity term in + try + let ps_set = DiscriminationTree.find ps tree in + A.exists test ps_set + with Not_found -> + false + ;; + + let head_of_term = function + | Cic.Appl (hd::tl) -> hd + | term -> term + ;; + + let rec skip_prods = function + | Cic.Prod (_,_,t) -> skip_prods t + | term -> term + ;; + + let rec subterm_at_pos pos term = + match pos with + | [] -> term + | index::pos -> + match term with + | Cic.Appl l -> + (try subterm_at_pos pos (List.nth l index) + with Failure _ -> raise Not_found) + | _ -> raise Not_found + ;; + + + let rec after_t pos term = + let pos' = + match pos with + | [] -> raise Not_found + | pos -> + List.fold_right + (fun i r -> if r = [] then [i+1] else i::r) pos [] + in + try + ignore(subterm_at_pos pos' term ); pos' + with Not_found -> + let pos, _ = + List.fold_right + (fun i (r, b) -> if b then (i::r, true) else (r, true)) + pos ([], false) + in + after_t pos term + ;; + + + let next_t pos term = + let t = subterm_at_pos pos term in + try + let _ = subterm_at_pos [1] t in + pos @ [1] + with Not_found -> + match pos with + | [] -> [1] + | pos -> after_t pos term + ;; + + let retrieve_generalizations (tree,arity) term = + let term = skip_prods term in + let rec retrieve tree term pos = + match tree with + | DiscriminationTree.Node (Some s, _) when pos = [] -> s + | DiscriminationTree.Node (_, map) -> + let res = + let hd_term = + elem_of_cic (head_of_term (subterm_at_pos pos term)) + in + if hd_term = Variable then A.empty else + try + let n = PSMap.find hd_term map in + match n with + | DiscriminationTree.Node (Some s, _) -> s + | DiscriminationTree.Node (None, _) -> + let newpos = + try next_t pos term + with Not_found -> [] + in + retrieve n term newpos + with Not_found -> + A.empty + in + try + let n = PSMap.find Variable map in + let newpos = try after_t pos term with Not_found -> [-1] in + if newpos = [-1] then + match n with + | DiscriminationTree.Node (Some s, _) -> A.union s res + | _ -> res + else + A.union res (retrieve n term newpos) + with Not_found -> + res + in + retrieve tree term [] + ;; + + + let jump_list arities = function + | DiscriminationTree.Node (value, map) -> + let rec get n tree = + match tree with + | DiscriminationTree.Node (v, m) -> + if n = 0 then + [tree] + else + PSMap.fold + (fun k v res -> + let a = + try List.assoc k arities + with Not_found -> 0 + in + (get (n-1 + a) v) @ res) m [] + in + PSMap.fold + (fun k v res -> + let arity = + try + List.assoc k arities + with Not_found -> 0 in + (get arity v) @ res) + map [] + ;; + + + let retrieve_unifiables (tree,arities) term = + let term = skip_prods term in + let rec retrieve tree term pos = + match tree with + | DiscriminationTree.Node (Some s, _) when pos = [] -> s + | DiscriminationTree.Node (_, map) -> + let subterm = + try Some (subterm_at_pos pos term) with Not_found -> None + in + match subterm with + | None -> A.empty + | Some (Cic.Meta _) -> + let newpos = try next_t pos term with Not_found -> [] in + let jl = jump_list arities tree in + List.fold_left + (fun r s -> A.union r s) + A.empty + (List.map (fun t -> retrieve t term newpos) jl) + | Some subterm -> + let res = + let hd_term = elem_of_cic (head_of_term subterm) in + if hd_term = Variable then + A.empty else + try + let n = PSMap.find hd_term map in + match n with + | DiscriminationTree.Node (Some s, _) -> s + | DiscriminationTree.Node (None, _) -> + retrieve n term (next_t pos term) + with Not_found -> + A.empty + in + try + let n = PSMap.find Variable map in + let newpos = + try after_t pos term + with Not_found -> [-1] + in + if newpos = [-1] then + match n with + | DiscriminationTree.Node (Some s, _) -> + A.union s res + | _ -> res + else + A.union res (retrieve n term newpos) + with Not_found -> + res + in + retrieve tree term [] + end +;; +