+++ /dev/null
-(* 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
- prerr_endline (s ^ "\n" ^ List.fold_right debug_aux (t::env) "")
-;;
-
-exception Impossible of int;;
-exception ReferenceToConstant;;
-exception ReferenceToVariable;;
-exception ReferenceToCurrentProof;;
-exception ReferenceToInductiveDefinition;;
-exception RelToHiddenHypothesis;;
-
-(* takes a well-typed term *)
-let whd context =
- let rec whdaux l =
- let module C = Cic in
- let module S = CicSubstitution in
- function
- C.Rel n as t ->
- (match List.nth context (n-1) with
- Some (_, C.Decl _) -> if l = [] then t else C.Appl (t::l)
- | Some (_, C.Def (bo,_)) -> whdaux l (S.lift n bo)
- | None -> raise RelToHiddenHypothesis
- )
- | C.Var (uri,exp_named_subst) as t ->
- let o,_ =
- CicEnvironment.get_cooked_obj ~trust:false CicUniv.empty_ugraph uri
- in
- (match o with
- C.Constant _ -> raise ReferenceToConstant
- | 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 (CicSubstitution.subst_vars exp_named_subst 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,exp_named_subst) as t ->
- let o,_ =
- CicEnvironment.get_cooked_obj ~trust:false CicUniv.empty_ugraph uri
- in
- (match o with
- C.Constant (_,Some body,_,_,_) ->
- whdaux l (CicSubstitution.subst_vars exp_named_subst body)
- | C.Constant _ -> if l = [] then t else C.Appl (t::l)
- | C.Variable _ -> raise ReferenceToVariable
- | C.CurrentProof (_,_,body,_,_,_) ->
- whdaux l (CicSubstitution.subst_vars exp_named_subst body)
- | C.InductiveDefinition _ -> raise ReferenceToInductiveDefinition
- )
- | C.MutInd _ as t -> if l = [] then t else C.Appl (t::l)
- | C.MutConstruct _ as t -> if l = [] then t else C.Appl (t::l)
- | C.MutCase (mutind,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) =
- let o,_ = CicEnvironment.get_obj CicUniv.empty_ugraph mutind in
- match o with
- C.InductiveDefinition (tl,ingredients,r,_) ->
- let (_,_,arity,_) = List.nth tl i in
- (arity,r)
- | _ -> raise WrongUriToInductiveDefinition
- in
- let ts =
- 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 (r,tl)
- in
- whdaux (ts@l) (List.nth pl (j-1))
- | C.Cast _ | C.Implicit _ ->
- raise (Impossible 2) (* we don't trust our whd ;-) *)
- | _ -> if l = [] then t else C.Appl (t::l)
- )
- | 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 ->
- if l = [] then t else C.Appl (t::l)
- in
-(*CSC
-function t ->
-prerr_endline ("PRIMA WHD" ^ CicPp.ppterm t) ; flush stderr ;
-List.iter (function (Cic.Decl t) -> prerr_endline ("Context: " ^ CicPp.ppterm t) | (Cic.Def t) -> prerr_endline ("Context:= " ^ CicPp.ppterm t)) context ; flush stderr ; prerr_endline "<PRIMA WHD" ; flush stderr ;
-let res =
-*)
- whdaux []
-(*CSC
-t in prerr_endline "DOPO WHD" ; flush stderr ; res
-*)
-;;
-
-(* t1, t2 must be well-typed *)
-let are_convertible c t1 t2 ugraph =
- let module U = UriManager in
- let rec aux test_equality_only context t1 t2 ugraph =
- let aux2 test_equality_only t1 t2 ugraph =
- (* 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,ugraph
- else
- begin
- let module C = Cic in
- match (t1,t2) with
- (C.Rel n1, C.Rel n2) -> (n1 = n2),ugraph
- | (C.Var (uri1,exp_named_subst1), C.Var (uri2,exp_named_subst2)) ->
- let b = U.eq uri1 uri2 in
- if b then
- (try
- List.fold_right2
- (fun (uri1,x) (uri2,y) (b,ugraph) ->
- (* FIXME: lazy! *)
- let b',ugraph' = aux test_equality_only context x y ugraph in
- (U.eq uri1 uri2 && b' && b),ugraph'
- ) exp_named_subst1 exp_named_subst2 (true,ugraph)
- with
- Invalid_argument _ -> false,ugraph
- )
- else
- false,ugraph
- | (C.Meta (n1,l1), C.Meta (n2,l2)) ->
- let b = n1 = n2 in
- if b then
- List.fold_left2
- (fun (b,ugraph) t1 t2 ->
- if b then
- match t1,t2 with
- None,_
- | _,None -> true,ugraph
- | Some t1',Some t2' ->
- aux test_equality_only context t1' t2' ugraph
- else
- false,ugraph
- ) (true,ugraph) l1 l2
- else
- false,ugraph
- (* TASSI: CONSTRAINTS *)
- | (C.Sort (C.Type t1), C.Sort (C.Type t2)) when test_equality_only ->
- true,(CicUniv.add_eq t2 t1 ugraph)
- (* TASSI: CONSTRAINTS *)
- | (C.Sort (C.Type t1), C.Sort (C.Type t2)) ->
- true,(CicUniv.add_ge t2 t1 ugraph)
- (* TASSI: CONSTRAINTS *)
- | (C.Sort s1, C.Sort (C.Type _)) -> (not test_equality_only),ugraph
- (* TASSI: CONSTRAINTS *)
- | (C.Sort s1, C.Sort s2) -> (s1 = s2),ugraph
- | (C.Prod (name1,s1,t1), C.Prod(_,s2,t2)) ->
- let b',ugraph' = aux true context s1 s2 ugraph in
- if b' then
- aux test_equality_only ((Some (name1, (C.Decl s1)))::context)
- t1 t2 ugraph'
- else
- false,ugraph
- | (C.Lambda (name1,s1,t1), C.Lambda(_,s2,t2)) ->
- let b',ugraph' = aux test_equality_only context s1 s2 ugraph in
- if b' then
- aux test_equality_only ((Some (name1, (C.Decl s1)))::context)
- t1 t2 ugraph'
- else
- false,ugraph
- | (C.LetIn (name1,s1,t1), C.LetIn(_,s2,t2)) ->
- let b',ugraph' = aux test_equality_only context s1 s2 ugraph in
- if b' then
- aux test_equality_only
- ((Some (name1, (C.Def (s1,None))))::context) t1 t2 ugraph'
- else
- false,ugraph
- | (C.Appl l1, C.Appl l2) ->
- (try
- List.fold_right2
- (fun x y (b,ugraph) ->
- if b then
- aux test_equality_only context x y ugraph
- else
- false,ugraph) l1 l2 (true,ugraph)
- with
- Invalid_argument _ -> false,ugraph
- )
- | (C.Const (uri1,exp_named_subst1), C.Const (uri2,exp_named_subst2)) ->
- let b' = U.eq uri1 uri2 in
- if b' then
- (try
- List.fold_right2
- (fun (uri1,x) (uri2,y) (b,ugraph) ->
- if b && U.eq uri1 uri2 then
- aux test_equality_only context x y ugraph
- else
- false,ugraph
- ) exp_named_subst1 exp_named_subst2 (true,ugraph)
- with
- Invalid_argument _ -> false,ugraph
- )
- else
- false,ugraph
- | (C.MutInd (uri1,i1,exp_named_subst1),
- C.MutInd (uri2,i2,exp_named_subst2)
- ) ->
- let b' = U.eq uri1 uri2 && i1 = i2 in
- if b' then
- (try
- List.fold_right2
- (fun (uri1,x) (uri2,y) (b,ugraph) ->
- if b && U.eq uri1 uri2 then
- aux test_equality_only context x y ugraph
- else
- false,ugraph
- ) exp_named_subst1 exp_named_subst2 (true,ugraph)
- with
- Invalid_argument _ -> false,ugraph
- )
- else
- false,ugraph
- | (C.MutConstruct (uri1,i1,j1,exp_named_subst1),
- C.MutConstruct (uri2,i2,j2,exp_named_subst2)
- ) ->
- let b' = U.eq uri1 uri2 && i1 = i2 && j1 = j2 in
- if b' then
- (try
- List.fold_right2
- (fun (uri1,x) (uri2,y) (b,ugraph) ->
- if b && U.eq uri1 uri2 then
- aux test_equality_only context x y ugraph
- else
- false,ugraph
- ) exp_named_subst1 exp_named_subst2 (true,ugraph)
- with
- Invalid_argument _ -> false,ugraph
- )
- else
- false,ugraph
- | (C.MutCase (uri1,i1,outtype1,term1,pl1),
- C.MutCase (uri2,i2,outtype2,term2,pl2)) ->
- let b' = U.eq uri1 uri2 && i1 = i2 in
- if b' then
- let b'',ugraph''=aux test_equality_only context
- outtype1 outtype2 ugraph in
- if b'' then
- let b''',ugraph'''= aux test_equality_only context
- term1 term2 ugraph'' in
- List.fold_right2
- (fun x y (b,ugraph) ->
- if b then
- aux test_equality_only context x y ugraph
- else
- false,ugraph)
- pl1 pl2 (true,ugraph''')
- else
- false,ugraph
- else
- false,ugraph
- | (C.Fix (i1,fl1), C.Fix (i2,fl2)) ->
- let tys =
- List.map (function (n,_,ty,_) -> Some (C.Name n,(C.Decl ty))) fl1
- in
- if i1 = i2 then
- List.fold_right2
- (fun (_,recindex1,ty1,bo1) (_,recindex2,ty2,bo2) (b,ugraph) ->
- if b && recindex1 = recindex2 then
- let b',ugraph' = aux test_equality_only context ty1 ty2
- ugraph in
- if b' then
- aux test_equality_only (tys@context) bo1 bo2 ugraph'
- else
- false,ugraph
- else
- false,ugraph)
- fl1 fl2 (true,ugraph)
- else
- false,ugraph
- | (C.CoFix (i1,fl1), C.CoFix (i2,fl2)) ->
- let tys =
- List.map (function (n,ty,_) -> Some (C.Name n,(C.Decl ty))) fl1
- in
- if i1 = i2 then
- List.fold_right2
- (fun (_,ty1,bo1) (_,ty2,bo2) (b,ugraph) ->
- if b then
- let b',ugraph' = aux test_equality_only context ty1 ty2
- ugraph in
- if b' then
- aux test_equality_only (tys@context) bo1 bo2 ugraph'
- else
- false,ugraph
- else
- false,ugraph)
- fl1 fl2 (true,ugraph)
- else
- false,ugraph
- | (C.Cast _, _) | (_, C.Cast _)
- | (C.Implicit _, _) | (_, C.Implicit _) ->
- assert false
- | (_,_) -> false,ugraph
- end
- in
- let b,ugraph' = aux2 test_equality_only t1 t2 ugraph in
- if b then
- b,ugraph'
- else
- begin
- debug t1 [t2] "PREWHD";
- let t1' = whd context t1 in
- let t2' = whd context t2 in
- debug t1' [t2'] "POSTWHD";
- aux2 test_equality_only t1' t2' ugraph
- end
- in
- aux false c t1 t2 ugraph
-;;