Bug fixed: the debrujinate function (hence the one to compute objects height)

[helm.git] / helm / software / components / ng_kernel / nCicTypeChecker.ml

diff --git a/helm/software/components/ng_kernel/nCicTypeChecker.ml b/helm/software/components/ng_kernel/nCicTypeChecker.ml
index 8beca4cf0504285f32355529739aabfa73700e1a..c4c2af477d3a510e33846f2bec5f827635a16ef3 100644 (file)
--- a/helm/software/components/ng_kernel/nCicTypeChecker.ml
+++ b/helm/software/components/ng_kernel/nCicTypeChecker.ml
@@ -96,13 +96,22 @@ let fixed_args bos j n nn =
    (let rec f = function 0 -> [] | n -> true :: f (n-1) in f j) bos
 ;;
 
-let debruijn uri number_of_types context = 
+let debruijn uri number_of_types ~subst context = 
+(* manca la subst! *)
  let rec aux k t =
   match t with
-   | C.Meta (i,(s,C.Ctx l)) ->
-      let l1 = HExtlib.sharing_map (aux (k-s)) l in
-      if l1 == l then t else C.Meta (i,(s,C.Ctx l1))
-   | C.Meta _ -> t
+   | C.Meta (i,(s,l)) ->
+      (try
+        let _,_,term,_ = U.lookup_subst i subst in
+        let ts = S.subst_meta (0,l) term in
+        let ts' = aux (k-s) ts in
+         if ts == ts' then t else ts'
+       with U.Subst_not_found _ ->
+        match l with
+           C.Ctx l ->
+            let l1 = HExtlib.sharing_map (aux (k-s)) l in
+            if l1 == l then t else C.Meta (i,(s,C.Ctx l1))
+         | _ -> t)
    | C.Const (Ref.Ref (uri1,(Ref.Fix (no,_,_) | Ref.CoFix no))) 
    | C.Const (Ref.Ref (uri1,Ref.Ind (_,no,_))) when NUri.eq uri uri1 ->
       C.Rel (k + number_of_types - no)
@@ -166,7 +175,7 @@ let specialize_and_abstract_constrs ~subst r_uri r_len context ty_term =
     | _ -> assert false
   in
   context_dcl,
-  List.map (fun (_,id,ty) -> id, debruijn r_uri r_len context ty) cl,
+  List.map (fun (_,id,ty) -> id, debruijn r_uri r_len ~subst context ty) cl,
   len, len + r_len
 ;;
 
@@ -695,7 +704,7 @@ and eat_prods ~subst ~metasenv context he ty_he args_with_ty =
 
 and is_non_recursive_singleton ~subst (Ref.Ref (uri,_)) iname ity cty =
      let ctx = [iname, C.Decl ity] in
-     let cty = debruijn uri 1 [] cty in
+     let cty = debruijn uri 1 [] ~subst cty in
      let len = List.length ctx in
      let rec aux ctx n nn t =
        match R.whd ~subst ctx t with
@@ -733,7 +742,7 @@ and check_mutual_inductive_defs uri ~metasenv ~subst leftno tyl =
           let k_relev =
             try snd (HExtlib.split_nth leftno k_relev)
             with Failure _ -> k_relev in
-           let te = debruijn uri len [] te in
+           let te = debruijn uri len [] ~subst te in
            let context,te = NCicReduction.split_prods ~subst tys leftno te in
            let _,chopped_context_rev =
             HExtlib.split_nth (List.length tys) (List.rev context) in
@@ -744,13 +753,11 @@ and check_mutual_inductive_defs uri ~metasenv ~subst leftno tyl =
               (fun context item1 item2 ->
                 let convertible =
                  match item1,item2 with
-                   (n1,C.Decl ty1),(n2,C.Decl ty2) ->
-                     n1 = n2 && 
+                   (_,C.Decl ty1),(_,C.Decl ty2) ->
                      R.are_convertible ~metasenv ~subst context ty1 ty2
-                 | (n1,C.Def (bo1,ty1)),(n2,C.Def (bo2,ty2)) ->
-                     n1 = n2
-                     && R.are_convertible ~metasenv ~subst context ty1 ty2
-                     && R.are_convertible ~metasenv ~subst context bo1 bo2
+                 | (_,C.Def (bo1,ty1)),(_,C.Def (bo2,ty2)) ->
+                     R.are_convertible ~metasenv ~subst context ty1 ty2 &&
+                      R.are_convertible ~metasenv ~subst context bo1 bo2
                  | _,_ -> false
                 in
                  if not convertible then
@@ -866,7 +873,7 @@ and guarded_by_destructors r_uri r_len ~subst ~metasenv context recfuns t =
         List.split (List.map (fun (_,name,_,ty,bo) -> (name, C.Decl ty), bo) fl)
       in
       let fl_len = List.length fl in
-      let bos = List.map (debruijn uri fl_len context) bos in
+      let bos = List.map (debruijn uri fl_len context ~subst) bos in
       let j = List.fold_left min max_int (List.map (fun (_,_,i,_,_)->i) fl) in
       let ctx_len = List.length context in
         (* we may look for fixed params not only up to j ... *)
@@ -1079,8 +1086,8 @@ and type_of_constant ((Ref.Ref (uri,_)) as ref) =
       let _,_,recno1,arity,_ = List.nth fl i in
       if h1 <> h2 || recno1 <> recno2 then error ();
       arity
-  | (_,_,_,_,C.Constant (_,_,_,ty,_)), Ref.Ref (_,Ref.Decl) -> ty
-  | (_,h1,_,_,C.Constant (_,_,_,ty,_)), Ref.Ref (_,Ref.Def h2) ->
+  | (_,_,_,_,C.Constant (_,_,None,ty,_)), Ref.Ref (_,Ref.Decl) -> ty
+  | (_,h1,_,_,C.Constant (_,_,Some _,ty,_)), Ref.Ref (_,Ref.Def h2) ->
      if h1 <> h2 then error ();
      ty
   | _ ->
@@ -1183,9 +1190,52 @@ let typecheck_subst ~metasenv subst =
     ) [] subst)
 ;;
 
+let height_of_term tl =
+ let h = ref 0 in
+ let get_height (NReference.Ref (uri,_)) =
+  let _,height,_,_,_ = NCicEnvironment.get_checked_obj uri in
+   height in
+ let rec aux =
+  function
+     NCic.Meta (_,(_,NCic.Ctx l)) -> List.iter aux l
+   | NCic.Meta _ -> ()
+   | NCic.Rel _
+   | NCic.Sort _ -> ()
+   | NCic.Implicit _ -> assert false
+   | NCic.Const nref -> h := max !h (get_height nref)
+   | NCic.Prod (_,t1,t2)
+   | NCic.Lambda (_,t1,t2) -> aux t1; aux t2
+   | NCic.LetIn (_,s,ty,t) -> aux s; aux ty; aux t
+   | NCic.Appl l -> List.iter aux l
+   | NCic.Match (_,outty,t,pl) -> aux outty; aux t; List.iter aux pl
+ in
+  List.iter aux tl;
+  1 + !h
+;;
+
+let height_of_obj_kind uri ~subst =
+ function
+    NCic.Inductive _
+  | NCic.Constant (_,_,None,_,_)
+  | NCic.Fixpoint (false,_,_) -> 0
+  | NCic.Fixpoint (true,ifl,_) ->
+     let iflno = List.length ifl in
+      height_of_term
+       (List.fold_left
+        (fun l (_,_,_,ty,bo) ->
+          let bo = debruijn uri iflno [] ~subst bo in
+           ty::bo::l
+       ) [] ifl)
+  | NCic.Constant (_,_,Some bo,ty,_) -> height_of_term [bo;ty]
+;;
 
-let typecheck_obj (uri,_height,metasenv,subst,kind) =
- (* height is not checked since it is only used to implement an optimization *)
+let typecheck_obj (uri,height,metasenv,subst,kind) =
+(*height must be checked since it is not only an optimization during reduction*)
+ let iheight = height_of_obj_kind uri ~subst kind in
+ if height <> iheight then
+  raise (TypeCheckerFailure (lazy (Printf.sprintf
+   "the declared object height (%d) is not the inferred one (%d)"
+   height iheight)));
  typecheck_metasenv metasenv;
  typecheck_subst ~metasenv subst;
  match kind with
@@ -1218,7 +1268,7 @@ let typecheck_obj (uri,_height,metasenv,subst,kind) =
       let dfl, kl =   
         List.split (List.map2 
           (fun (_,_,_,_,bo) rno -> 
-             let dbo = debruijn uri len [] bo in
+             let dbo = debruijn uri len [] ~subst bo in
              dbo, Evil rno)
           fl kl)
       in