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diff --git a/helm/ocaml/library/cicCoercion.ml b/helm/ocaml/library/cicCoercion.ml
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+(* Copyright (C) 2005, 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://helm.cs.unibo.it/
+ *)
+
+(* $Id$ *)
+
+let debug = false
+let debug_print s = if debug then prerr_endline (Lazy.force s) else ()
+
+(* given the new coercion uri from src to tgt returns the list 
+ * of new coercions to create. hte list elements are
+ * (source, list of coercions to follow, target)
+ *)
+let get_closure_coercions src tgt uri coercions =
+  let eq_carr s t = 
+    try
+      CoercDb.eq_carr s t
+    with
+    | CoercDb.EqCarrNotImplemented _ | CoercDb.EqCarrOnNonMetaClosed -> false
+  in
+  match src,tgt with
+  | CoercDb.Uri _, CoercDb.Uri _ ->
+      let c_from_tgt = 
+        List.filter (fun (f,_,_) -> eq_carr f tgt) coercions 
+      in
+      let c_to_src = 
+        List.filter (fun (_,t,_) -> eq_carr t src) coercions 
+      in
+        (List.map (fun (_,t,u) -> src,[uri; u],t) c_from_tgt) @
+        (List.map (fun (s,_,u) -> s,[u; uri],tgt) c_to_src) @
+        (List.fold_left (
+          fun l (s,_,u1) ->
+            ((List.map (fun (_,t,u2) ->
+              (s,[u1;uri;u2],t)
+            )c_from_tgt)@l) )
+        [] c_to_src)
+  | _ -> [] (* do not close in case source or target is not an indty ?? *)
+;;
+
+let obj_attrs = [`Class `Coercion; `Generated]
+
+(* generate_composite_closure (c2 (c1 s)) in the universe graph univ *)
+let generate_composite_closure c1 c2 univ =
+  let c1_ty,univ = CicTypeChecker.type_of_aux' [] [] c1 univ in
+  let rec mk_rels n =
+    match n with 
+    | 0 -> []
+    | _ -> (Cic.Rel n) :: (mk_rels (n-1))
+  in
+  let rec compose k =
+    function 
+    | Cic.Prod (name,src,tgt) -> 
+        let name =
+          match name with
+          | Cic.Anonymous -> Cic.Name "x"
+          | _ -> name
+        in
+          Cic.Lambda (name,src,compose (k+1) tgt)
+    | Cic.Appl (he::tl) -> 
+        Cic.Appl (c2 :: tl @ [Cic.Appl (c1 :: (mk_rels k)) ])
+    | _ -> Cic.Appl (c2 :: [Cic.Appl (c1 :: (mk_rels k)) ])
+  in
+  let c = compose 0 c1_ty in
+  let c_ty,univ = 
+    try 
+      CicTypeChecker.type_of_aux' [] [] c univ
+    with CicTypeChecker.TypeCheckerFailure s as exn ->
+      debug_print (lazy (Printf.sprintf "Generated composite coercion:\n%s\n%s" 
+        (CicPp.ppterm c) (Lazy.force s)));
+      raise exn
+  in
+  let cleaned_ty =
+    FreshNamesGenerator.clean_dummy_dependent_types c_ty 
+  in
+  let obj = Cic.Constant ("xxxx",Some c,cleaned_ty,[],obj_attrs) in 
+    obj,univ
+;;
+
+(* removes from l the coercions that are in !coercions *)
+let filter_duplicates l coercions =
+  List.filter (
+      fun (src,_,tgt) ->
+        not (List.exists (fun (s,t,u) -> 
+          CoercDb.eq_carr s src && 
+          CoercDb.eq_carr t tgt)
+        coercions))
+  l
+
+(* given a new coercion uri from src to tgt returns 
+ * a list of (new coercion uri, coercion obj, universe graph) 
+ *)
+let close_coercion_graph src tgt uri =
+  (* check if the coercion already exists *)
+  let coercions = CoercDb.to_list () in
+  let todo_list = get_closure_coercions src tgt uri coercions in
+  let todo_list = filter_duplicates todo_list coercions in
+  let new_coercions = 
+    List.map (
+      fun (src, l , tgt) ->
+        match l with
+        | [] -> assert false 
+        | he :: tl ->
+            let first_step = 
+              Cic.Constant ("", 
+                Some (CoercDb.term_of_carr (CoercDb.Uri he)),
+                Cic.Sort Cic.Prop, [], obj_attrs)
+            in
+            let o,_ = 
+              List.fold_left (fun (o,univ) coer ->
+                match o with 
+                | Cic.Constant (_,Some c,_,[],_) ->
+                    generate_composite_closure c (CoercDb.term_of_carr (CoercDb.Uri
+                    coer)) univ
+                | _ -> assert false 
+              ) (first_step, CicUniv.empty_ugraph) tl
+            in
+            let name_src = CoercDb.name_of_carr src in
+            let name_tgt = CoercDb.name_of_carr tgt in
+            let name = name_tgt ^ "_of_" ^ name_src in
+            let buri = UriManager.buri_of_uri uri in
+            let c_uri = 
+              UriManager.uri_of_string (buri ^ "/" ^ name ^ ".con") 
+            in
+            let named_obj = 
+              match o with
+              | Cic.Constant (_,bo,ty,vl,attrs) ->
+                  Cic.Constant (name,bo,ty,vl,attrs)
+              | _ -> assert false 
+            in
+              ((src,tgt,c_uri,named_obj))
+    ) todo_list
+  in
+  new_coercions
+;;
+