X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Fsoftware%2Fcomponents%2Fng_kernel%2FnCicEnvironment.ml;h=f31c4e9b1ebbc71416ced0dbbc120e4bf60c7448;hb=718d9bcfb53dd76a5c0622aff9fed69a68769324;hp=0ddd3601db02f4502f0cc0d9780adaff6b74584a;hpb=1ee5193677b8e2a80d4f068ee79ecac335de1196;p=helm.git

diff --git a/helm/software/components/ng_kernel/nCicEnvironment.ml b/helm/software/components/ng_kernel/nCicEnvironment.ml
index 0ddd3601d..f31c4e9b1 100644
--- a/helm/software/components/ng_kernel/nCicEnvironment.ml
+++ b/helm/software/components/ng_kernel/nCicEnvironment.ml
@@ -16,11 +16,17 @@ module Ref = NReference
 
 exception CircularDependency of string Lazy.t;;
 exception ObjectNotFound of string Lazy.t;;
-exception BadDependency of string Lazy.t;;
+exception BadDependency of string Lazy.t * exn;;
 exception BadConstraint of string Lazy.t;;
 
 let type0 = []
 
+let max l1 l2 =
+ HExtlib.list_uniq ~eq:(fun (b1,u1) (b2,u2) -> b1=b2 && NUri.eq u1 u2)
+  (List.sort (fun (b1,u1) (b2,u2) ->
+    let res = compare b1 b2 in if res = 0 then NUri.compare u1 u2 else res)
+      (l1 @ l2))
+
 let le_constraints = ref [] (* strict,a,b *)
 
 let rec le_path_uri avoid strict a b =
@@ -41,7 +47,15 @@ let universe_leq a b =
      raise (BadConstraint
       (lazy "trying to check if a universe is less or equal than an inferred universe"))
 
-let universe_eq a b = universe_leq b a && universe_leq a b
+let universe_eq a b = 
+  match a,b with 
+  | [(false,_)], [(false,_)] -> universe_leq b a && universe_leq a b
+  | _, [(false,_)]
+  | [(false,_)],_ -> false
+  | _ ->
+     raise (BadConstraint
+      (lazy "trying to check if two inferred universes are equal"))
+;;
 
 let pp_constraint b x y =  
   NUri.name_of_uri x ^ (if b then " < " else " <= ") ^ NUri.name_of_uri y
@@ -126,11 +140,12 @@ let get_checked_obj u =
         Sys.Break as e ->
          frozen_list := saved_frozen_list;
          raise e
-      | Propagate (u',_) as e' ->
+      | Propagate (u',old_exn) as e' ->
          frozen_list := saved_frozen_list;
          let exn = `Exn (BadDependency (lazy (NUri.string_of_uri u ^
            " depends (recursively) on " ^ NUri.string_of_uri u' ^
-           " which is not well-typed"))) in
+           " which is not well-typed"), 
+           match old_exn with BadDependency (_,e) -> e | _ -> old_exn)) in
          NUri.UriHash.add cache u exn;
          if saved_frozen_list = [] then
           exn