From: Andrea Asperti <andrea.asperti@unibo.it>
Date: Tue, 16 Apr 2002 08:41:29 +0000 (+0000)
Subject: Replaced with a symbolic link to the actual implementation.
X-Git-Tag: V_0_3_0_debian_8~157
X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=commitdiff_plain;h=7c3d544d25bbe7e38e5041c0e75950d5e6a328b3;p=helm.git

Replaced with a symbolic link to the actual implementation.
The symbolic link must be created after check-out.
---

diff --git a/helm/ocaml/cic_proof_checking/cicReduction.ml b/helm/ocaml/cic_proof_checking/cicReduction.ml
deleted file mode 100644
index ac1b50d31..000000000
--- a/helm/ocaml/cic_proof_checking/cicReduction.ml
+++ /dev/null
@@ -1,265 +0,0 @@
-(* Copyright (C) 2000, 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 CicReductionInternalError;;
-exception WrongUriToInductiveDefinition;;
-
-let fdebug = ref 1;;
-let debug t env s =
- let rec debug_aux t i =
-  let module C = Cic in
-  let module U = UriManager in
-   CicPp.ppobj (C.Variable ("DEBUG", None, t)) ^ "\n" ^ i
- in
-  if !fdebug = 0 then
-   begin
-    print_endline (s ^ "\n" ^ List.fold_right debug_aux (t::env) "") ;
-    flush stdout
-   end
-;;
-
-exception Impossible of int;;
-exception ReferenceToDefinition;;
-exception ReferenceToAxiom;;
-exception ReferenceToVariable;;
-exception ReferenceToCurrentProof;;
-exception ReferenceToInductiveDefinition;;
-
-(* takes a well-typed term *)
-let whd =
- let rec whdaux l =
-  let module C = Cic in
-  let module S = CicSubstitution in
-   function
-      C.Rel _ as t -> if l = [] then t else C.Appl (t::l)
-    | C.Var uri as t ->
-       (match CicEnvironment.get_cooked_obj uri 0 with
-           C.Definition _ -> raise ReferenceToDefinition
-         | C.Axiom _ -> raise ReferenceToAxiom
-         | C.CurrentProof _ -> raise ReferenceToCurrentProof
-         | C.InductiveDefinition _ -> raise ReferenceToInductiveDefinition
-         | C.Variable (_,None,_) -> if l = [] then t else C.Appl (t::l)
-         | C.Variable (_,Some body,_) -> whdaux l body
-       )
-    | C.Meta _ as t -> if l = [] then t else C.Appl (t::l)
-    | C.Sort _ as t -> t (* l should be empty *)
-    | C.Implicit as t -> t
-    | C.Cast (te,ty) -> whdaux l te  (*CSC E' GIUSTO BUTTARE IL CAST? *)
-    | C.Prod _ as t -> t (* l should be empty *)
-    | C.Lambda (name,s,t) as t' ->
-       (match l with
-           [] -> t'
-         | he::tl -> whdaux tl (S.subst he t)
-           (* when name is Anonimous the substitution should be superfluous *)
-       )
-    | C.LetIn (n,s,t) -> whdaux l (S.subst (whdaux [] s) t)
-    | C.Appl (he::tl) -> whdaux (tl@l) he
-    | C.Appl [] -> raise (Impossible 1)
-    | C.Const (uri,cookingsno) as t ->
-       (match CicEnvironment.get_cooked_obj uri cookingsno with
-           C.Definition (_,body,_,_) -> whdaux l body
-         | C.Axiom _ -> if l = [] then t else C.Appl (t::l)
-         | C.Variable _ -> raise ReferenceToVariable
-         | C.CurrentProof (_,_,body,_) -> whdaux l body
-         | C.InductiveDefinition _ -> raise ReferenceToInductiveDefinition
-       )
-    | C.Abst _ as t -> t (*CSC l should be empty ????? *)
-    | C.MutInd (uri,_,_) as t -> if l = [] then t else C.Appl (t::l)
-    | C.MutConstruct (uri,_,_,_) as t -> if l = [] then t else C.Appl (t::l)
-    | C.MutCase (mutind,cookingsno,i,_,term,pl) as t ->
-       let decofix =
-        function
-           C.CoFix (i,fl) as t ->
-            let (_,_,body) = List.nth fl i in
-             let body' =
-              let counter = ref (List.length fl) in
-               List.fold_right
-                (fun _ -> decr counter ; S.subst (C.CoFix (!counter,fl)))
-                fl
-                body
-             in
-              whdaux [] body'
-         | C.Appl (C.CoFix (i,fl) :: tl) ->
-            let (_,_,body) = List.nth fl i in
-             let body' =
-              let counter = ref (List.length fl) in
-               List.fold_right
-                (fun _ -> decr counter ; S.subst (C.CoFix (!counter,fl)))
-                fl
-                body
-             in
-              whdaux tl body'
-         | t -> t
-       in
-        (match decofix (whdaux [] term) with
-            C.MutConstruct (_,_,_,j) -> whdaux l (List.nth pl (j-1))
-          | C.Appl (C.MutConstruct (_,_,_,j) :: tl) ->
-             let (arity, r, num_ingredients) =
-              match CicEnvironment.get_obj mutind with
-                 C.InductiveDefinition (tl,ingredients,r) ->
-                   let (_,_,arity,_) = List.nth tl i
-                   and num_ingredients =
-                    List.fold_right
-                     (fun (k,l) i ->
-                       if k < cookingsno then i + List.length l else i
-                     ) ingredients 0
-                   in
-                    (arity,r,num_ingredients)
-               | _ -> raise WrongUriToInductiveDefinition
-             in
-              let ts =
-               let num_to_eat = r + num_ingredients in
-                let rec eat_first =
-                 function
-                    (0,l) -> l
-                  | (n,he::tl) when n > 0 -> eat_first (n - 1, tl)
-                  | _ -> raise (Impossible 5)
-                in
-                 eat_first (num_to_eat,tl)
-              in
-               whdaux (ts@l) (List.nth pl (j-1))
-         | C.Abst _| C.Cast _ | C.Implicit ->
-            raise (Impossible 2) (* we don't trust our whd ;-) *)
-         | _ -> t
-       )
-    | C.Fix (i,fl) as t ->
-       let (_,recindex,_,body) = List.nth fl i in
-        let recparam =
-         try
-          Some (List.nth l recindex)
-         with
-          _ -> None
-        in
-         (match recparam with
-             Some recparam ->
-              (match whdaux [] recparam with
-                  C.MutConstruct _
-                | C.Appl ((C.MutConstruct _)::_) ->
-                   let body' =
-                    let counter = ref (List.length fl) in
-                     List.fold_right
-                      (fun _ -> decr counter ; S.subst (C.Fix (!counter,fl)))
-                      fl
-                      body
-                   in
-                    (* Possible optimization: substituting whd recparam in l *)
-                    whdaux l body'
-               | _ -> if l = [] then t else C.Appl (t::l)
-             )
-          | None -> if l = [] then t else C.Appl (t::l)
-         )
-    | C.CoFix (i,fl) as t ->
-       (*CSC vecchio codice
-       let (_,_,body) = List.nth fl i in
-        let body' =
-         let counter = ref (List.length fl) in
-          List.fold_right
-           (fun _ -> decr counter ; S.subst (C.CoFix (!counter,fl)))
-           fl
-           body
-        in
-         whdaux l body'
-       *)
-       if l = [] then t else C.Appl (t::l)
- in
-  whdaux []
-;;
-
-(* t1, t2 must be well-typed *)
-let are_convertible t1 t2 =
- let module U = UriManager in
- let rec aux t1 t2 =
-  debug t1 [t2] "PREWHD";
-  (* this trivial euristic cuts down the total time of about five times ;-) *)
-  (* this because most of the time t1 and t2 are "sintactically" the same   *)
-  if t1 = t2 then
-   true
-  else
-   begin
-    let module C = Cic in
-     let t1' = whd t1 
-     and t2' = whd t2 in
-     debug t1' [t2'] "POSTWHD";
-      match (t1',t2') with
-         (C.Rel n1, C.Rel n2) -> n1 = n2
-       | (C.Var uri1, C.Var uri2) -> U.eq uri1 uri2
-       | (C.Meta n1, C.Meta n2) -> n1 = n2
-       | (C.Sort s1, C.Sort s2) -> true (*CSC da finire con gli universi *)
-       | (C.Prod (_,s1,t1), C.Prod(_,s2,t2)) ->
-          aux s1 s2 && aux t1 t2
-       | (C.Lambda (_,s1,t1), C.Lambda(_,s2,t2)) ->
-          aux s1 s2 && aux t1 t2
-       | (C.Appl l1, C.Appl l2) ->
-          (try
-            List.fold_right2 (fun  x y b -> aux x y && b) l1 l2 true 
-           with
-            Invalid_argument _ -> false
-          )
-       | (C.Const (uri1,_), C.Const (uri2,_)) ->
-           (*CSC: questo commento e' chiaro o delirante? Io lo sto scrivendo *)
-           (*CSC: mentre sono delirante, quindi ...                          *)
-           (* WARNING: it is really important that the two cookingsno are not *)
-           (* checked for equality. This allows not to cook an object with no *)
-           (* ingredients only to update the cookingsno. E.g: if a term t has *)
-           (* a reference to a term t1 which does not depend on any variable  *)
-           (* and t1 depends on a term t2 (that can't depend on any variable  *)
-           (* because of t1), then t1 cooked at every level could be the same *)
-           (* as t1 cooked at level 0. Doing so, t2 will be extended in t     *)
-           (* with cookingsno 0 and not 2. But this will not cause any trouble*)
-           (* if here we don't check that the two cookingsno are equal.       *)
-           U.eq uri1 uri2
-       | (C.MutInd (uri1,k1,i1), C.MutInd (uri2,k2,i2)) ->
-           (* WARNIG: see the previous warning *)
-           U.eq uri1 uri2 && i1 = i2
-       | (C.MutConstruct (uri1,_,i1,j1), C.MutConstruct (uri2,_,i2,j2)) ->
-           (* WARNIG: see the previous warning *)
-           U.eq uri1 uri2 && i1 = i2 && j1 = j2
-       | (C.MutCase (uri1,_,i1,outtype1,term1,pl1),
-          C.MutCase (uri2,_,i2,outtype2,term2,pl2)) -> 
-           (* WARNIG: see the previous warning *)
-           (* aux outtype1 outtype2 should be true if aux pl1 pl2 *)
-           U.eq uri1 uri2 && i1 = i2 && aux outtype1 outtype2 &&
-            aux term1 term2 &&
-            List.fold_right2 (fun x y b -> b && aux x y) pl1 pl2 true
-       | (C.Fix (i1,fl1), C.Fix (i2,fl2)) ->
-          i1 = i2 &&
-           List.fold_right2
-            (fun (_,recindex1,ty1,bo1) (_,recindex2,ty2,bo2) b ->
-              b && recindex1 = recindex2 && aux ty1 ty2 && aux bo1 bo2)
-            fl1 fl2 true
-       | (C.CoFix (i1,fl1), C.CoFix (i2,fl2)) ->
-          i1 = i2 &&
-           List.fold_right2
-            (fun (_,ty1,bo1) (_,ty2,bo2) b ->
-              b && aux ty1 ty2 && aux bo1 bo2)
-            fl1 fl2 true
-       | (C.Abst _, _) | (_, C.Abst _) | (C.Cast _, _) | (_, C.Cast _)
-       | (C.Implicit, _) | (_, C.Implicit) ->
-          raise (Impossible 3) (* we don't trust our whd ;-) *)
-       | (_,_) -> false
-   end
- in
-  aux t1 t2
-;;