X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Focaml%2Fcic_proof_checking%2FcicTypeChecker.ml;h=04b769b5c2b68366d2c1f765a39d21f7b7f43f62;hb=a21777bd2ac02fd346f168ead468405e4c300855;hp=137f786ab1fc003e7432605ee82116a0e9d6093c;hpb=b3bfd6b249600b15552c890306a635aee30c2a74;p=helm.git

diff --git a/helm/ocaml/cic_proof_checking/cicTypeChecker.ml b/helm/ocaml/cic_proof_checking/cicTypeChecker.ml
index 137f786ab..04b769b5c 100644
--- a/helm/ocaml/cic_proof_checking/cicTypeChecker.ml
+++ b/helm/ocaml/cic_proof_checking/cicTypeChecker.ml
@@ -793,11 +793,12 @@ and guarded_by_destructors context n nn kl x safes =
  let module U = UriManager in
   function
      C.Rel m when m > n && m <= nn -> false
-   | C.Rel n ->
+   | C.Rel m ->
       (match List.nth context (n-1) with
           Some (_,C.Decl _) -> true
         | Some (_,C.Def (bo,_)) ->
-           guarded_by_destructors context n nn kl x safes bo
+           guarded_by_destructors context m nn kl x safes
+            (CicSubstitution.lift m bo)
 	| None -> raise (TypeCheckerFailure "Reference to deleted hypothesis")
       )
    | C.Meta _
@@ -1370,12 +1371,19 @@ and type_of_aux' metasenv context t =
        and sort2 = type_of_aux ((Some (name,(C.Decl s)))::context) t in
         sort_of_prod context (name,s) (sort1,sort2)
    | C.Lambda (n,s,t) ->
-       let sort1 = type_of_aux context s
-       and type2 = type_of_aux ((Some (n,(C.Decl s)))::context) t in
-        let sort2 = type_of_aux ((Some (n,(C.Decl s)))::context) type2 in
-         (* only to check if the product is well-typed *)
-         let _ = sort_of_prod context (n,s) (sort1,sort2) in
-          C.Prod (n,s,type2)
+       let sort1 = type_of_aux context s in
+       (match R.whd context sort1 with
+           C.Meta _
+         | C.Sort _ -> ()
+         | _ ->
+           raise
+            (TypeCheckerFailure (sprintf
+              "Not well-typed lambda-abstraction: the source %s should be a
+               type; instead it is a term of type %s" (CicPp.ppterm s)
+                (CicPp.ppterm sort1)))
+       ) ;
+       let type2 = type_of_aux ((Some (n,(C.Decl s)))::context) t in
+        C.Prod (n,s,type2)
    | C.LetIn (n,s,t) ->
       (* only to check if s is well-typed *)
       let ty = type_of_aux context s in
@@ -1615,7 +1623,7 @@ in if not res then debug_print ("#### " ^ CicPp.ppterm (type_of_aux context p) ^
          | Cic.Variable (_,None,_,_) -> ()
          | _ ->
             raise (TypeCheckerFailure
-              ("Unknown mutual inductive definition:" ^
+              ("Unknown variable definition:" ^
               UriManager.string_of_uri uri))
        ) ;
        let typeoft = type_of_aux context t in
@@ -1657,7 +1665,7 @@ in if not res then debug_print ("#### " ^ CicPp.ppterm (type_of_aux context p) ^
    | (hete, hety)::tl ->
     (match (CicReduction.whd context hetype) with
         Cic.Prod (n,s,t) ->
-         if CicReduction.are_convertible context s hety then
+         if CicReduction.are_convertible context hety s then
           (CicReduction.fdebug := -1 ;
            eat_prods context (CicSubstitution.subst hete t) tl
           )