X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Focaml%2Flibrary%2FcoercGraph.ml;h=cd958a8f62074aa5ba4ac76fb023043b2478587e;hb=771ee8b9d122fa963881c876e86f90531bb7434f;hp=d99fc6f798f67f72ccbee796adc50b8bd0db1474;hpb=727ef55d2a6202a989c274f6caa1b0e1b7307880;p=helm.git

diff --git a/helm/ocaml/library/coercGraph.ml b/helm/ocaml/library/coercGraph.ml
index d99fc6f79..cd958a8f6 100644
--- a/helm/ocaml/library/coercGraph.ml
+++ b/helm/ocaml/library/coercGraph.ml
@@ -23,6 +23,8 @@
  * http://cs.unibo.it/helm/.
  *)
 
+(* $Id$ *)
+
 open Printf;;
 
 type coercion_search_result = 
@@ -34,7 +36,6 @@ type coercion_search_result =
 let debug = false
 let debug_print s = if debug then prerr_endline (Lazy.force s) else ()
 
-
 (* searches a coercion fron src to tgt in the !coercions list *)
 let look_for_coercion src tgt =
   try 
@@ -75,136 +76,22 @@ let look_for_coercion src tgt =
   let tgt_uri = CoercDb.coerc_carr_of_term tgt in
   look_for_coercion src_uri tgt_uri
 
-(* 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]
+let is_a_coercion t = 
+  try
+    let uri = CicUtil.uri_of_term t in
+    CoercDb.is_a_coercion uri
+  with Invalid_argument _ -> false
 
-(* 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 (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
-
-let term_of_carr = function
-  | CoercDb.Uri u -> CicUtil.term_of_uri u
-  | CoercDb.Sort _ -> assert false 
-  | CoercDb.Term _ -> assert false
+let source_of t = 
+  try
+    let uri = CicUtil.uri_of_term t in
+    CoercDb.term_of_carr (fst (CoercDb.get_carr uri))
+  with Invalid_argument _ -> assert false (* t must be a coercion *)
   
-(* 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, new_coercions_obj = 
-    List.split (
-      List.map (
-        fun (src, l , tgt) ->
-          match l with
-          | [] -> assert false 
-          | he :: tl ->
-              let first_step = 
-                Cic.Constant ("", 
-                  Some (term_of_carr (CoercDb.Uri he)), Cic.Sort Cic.Prop, [], obj_attrs)
-              in
-              let o,u = 
-                List.fold_left (fun (o,univ) coer ->
-                  match o with 
-                  | Cic.Constant (_,Some c,_,[],_) ->
-                      generate_composite_closure c (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),(c_uri,named_obj,u))
-      ) todo_list)
-  in
-  List.iter CoercDb.add_coercion (new_coercions @ [src,tgt,uri]);
-  new_coercions_obj
-;;
-
+let target_of t =
+  try
+    let uri = CicUtil.uri_of_term t in
+    CoercDb.term_of_carr (snd (CoercDb.get_carr uri))
+  with Invalid_argument _ -> assert false (* t must be a coercion *)
+    
 (* EOF *)