fixed coercion mechanism w.r.t. undo/require

[helm.git] / helm / software / components / ng_refiner / nCicUnifHint.ml

diff --git a/helm/software/components/ng_refiner/nCicUnifHint.ml b/helm/software/components/ng_refiner/nCicUnifHint.ml
index abca189d9665bbd66503d641298b9d4e146339be..ce88085521c2ddabda8d96069f9fba79bb90a876 100644 (file)
--- a/helm/software/components/ng_refiner/nCicUnifHint.ml
+++ b/helm/software/components/ng_refiner/nCicUnifHint.ml
@@ -11,6 +11,9 @@
 
 (* $Id: nCicRefiner.mli 9227 2008-11-21 16:00:06Z tassi $ *)
 
+let debug s = prerr_endline (Lazy.force s);;
+let debug _ = ();;
+
 module COT : Set.OrderedType with type t = int * NCic.term = 
   struct
         type t = int * NCic.term
@@ -31,13 +34,20 @@ type db =
 
 exception HintNotValid
 
+let skel_dummy = NCic.Implicit `Type;;
+
+class type g_status =
+ object
+  method uhint_db: db
+ end
+
 class status =
  object
   val db = HDB.empty, EQDB.empty
   method uhint_db = db
   method set_uhint_db v = {< db = v >}
   method set_unifhint_status
-   : 'status. < uhint_db : db; .. > as 'status -> 'self
+   : 'status. #g_status as 'status -> 'self
    = fun o -> {< db = o#uhint_db >}
  end
 
@@ -52,6 +62,8 @@ let index_hint hdb context t1 t2 precedence =
     (match t2 with
     | NCic.Meta _ | NCic.Appl (NCic.Meta _ :: _) -> false | _ -> true)
   );
+  (* here we do not use skel_dummy since it could cause an assert false in 
+   * the subst function that lives in the kernel *)
   let hole = NCic.Meta (-1,(0,NCic.Irl 0)) in
   let t1_skeleton = 
     List.fold_left (fun t _ -> NCicSubstitution.subst hole t) t1 context
@@ -59,6 +71,12 @@ let index_hint hdb context t1 t2 precedence =
   let t2_skeleton = 
     List.fold_left (fun t _ -> NCicSubstitution.subst hole t) t2 context
   in
+  let rec cleanup_skeleton () = function
+    | NCic.Meta _ -> skel_dummy 
+    | t -> NCicUtils.map (fun _ () -> ()) () cleanup_skeleton t
+  in
+  let t1_skeleton = cleanup_skeleton () t1_skeleton in
+  let t2_skeleton = cleanup_skeleton () t2_skeleton in
   let src = pair t1_skeleton t2_skeleton in
   let ctx2abstractions context t = 
     List.fold_left 
@@ -71,11 +89,11 @@ let index_hint hdb context t1 t2 precedence =
   let data_hint = ctx2abstractions context (pair t1 t2) in
   let data_t1 = t2_skeleton in
   let data_t2 = t1_skeleton in
-(*
-  prerr_endline ("INDEXING: " ^ 
+
+  debug(lazy ("INDEXING: " ^ 
     NCicPp.ppterm ~metasenv:[] ~subst:[] ~context:[] src ^ " |==> " ^
-    NCicPp.ppterm ~metasenv:[] ~subst:[] ~context:[] data);
-*)
+    NCicPp.ppterm ~metasenv:[] ~subst:[] ~context:[] data_hint));
+
   hdb#set_uhint_db (
       HDB.index (fst (hdb#uhint_db)) src (precedence, data_hint),
       EQDB.index  
@@ -138,11 +156,6 @@ let db () =
           | b1,b2 -> 
               if NCicReduction.are_convertible ~subst:[] ~metasenv:[] ctx b1 b2 
               then begin
-(*
-                prerr_endline ("hint: " ^ NCicPp.ppterm ~metasenv:[] ~subst:[]
-                  ~context:ctx b1 ^ " === " ^ NCicPp.ppterm ~metasenv:[]
-                  ~subst:[] ~context:ctx b2);
-*)
               let rec mk_rels =  
                  function 0 -> [] | n -> NCic.Rel n :: mk_rels (n-1) 
               in 
@@ -201,6 +214,7 @@ let saturate ?(delta=0) metasenv subst context ty goal_arity =
 ;;
 
 let eq_class_of hdb t1 = 
+ let eq_class =
   if NDiscriminationTree.NCicIndexable.path_string_of t1 = 
      [Discrimination_tree.Variable]
   then
@@ -209,13 +223,19 @@ let eq_class_of hdb t1 =
   else
     let candidates = EQDB.retrieve_unifiables (snd hdb#uhint_db) t1 in
     let candidates = HintSet.elements candidates in
-    List.map snd (List.sort (fun (x,_) (y,_) -> compare x y) candidates)
+    let candidates = List.sort (fun (x,_) (y,_) -> compare x y) candidates in
+    List.map snd candidates
+ in
+ debug(lazy("eq_class of: " ^ NCicPp.ppterm ~metasenv:[] ~context:[] ~subst:[]
+   t1 ^ " is\n" ^ String.concat "\n" 
+   (List.map (NCicPp.ppterm ~subst:[] ~metasenv:[] ~context:[]) eq_class)));
+ eq_class   
 ;;
 
 let look_for_hint hdb metasenv subst context t1 t2 =
+  debug(lazy ("KEY1: "^NCicPp.ppterm ~metasenv ~subst ~context t1));
+  debug(lazy ("KEY2: "^NCicPp.ppterm ~metasenv ~subst ~context t2));
 (*
-  prerr_endline ("KEY1: "^NCicPp.ppterm ~metasenv ~subst ~context (pair t1 t2));
-  prerr_endline ("KEY2: "^NCicPp.ppterm ~metasenv ~subst ~context (pair t2 t1));
   HDB.iter hdb
    (fun p ds ->
       prerr_endline ("ENTRY: " ^
@@ -263,21 +283,20 @@ let look_for_hint hdb metasenv subst context t1 t2 =
     List.sort (fun (x,_,_,_) (y,_,_,_) -> Pervasives.compare x y) rc
   in 
   let rc = List.map (fun (_,x,y,z) -> x,y,z) rc in
-(*
-    prerr_endline "Hints:";
-    List.iter 
-      (fun (metasenv, (t1, t2), premises) ->
-          prerr_endline 
-          ("\t" ^ String.concat ";  "
-                (List.map (fun (a,b) -> 
-                   NCicPp.ppterm ~margin:max_int ~metasenv ~subst ~context a ^
-                   " =?= "^
-                   NCicPp.ppterm ~margin:max_int ~metasenv ~subst ~context b)
-                premises) ^     
-              "  ==> "^
-              NCicPp.ppterm ~margin:max_int ~metasenv ~subst ~context t1 ^
-              " = "^NCicPp.ppterm ~margin:max_int ~metasenv ~subst ~context t2))
-      rc;
-*)
+
+  debug(lazy ("Hints:"^
+    String.concat "\n" (List.map 
+     (fun (metasenv, (t1, t2), premises) ->
+         ("\t" ^ String.concat ";  "
+               (List.map (fun (a,b) -> 
+                  NCicPp.ppterm ~margin:max_int ~metasenv ~subst ~context a ^
+                  " =?= "^
+                  NCicPp.ppterm ~margin:max_int ~metasenv ~subst ~context b)
+               premises) ^     
+             "  ==> "^
+             NCicPp.ppterm ~margin:max_int ~metasenv ~subst ~context t1 ^
+             " = "^NCicPp.ppterm ~margin:max_int ~metasenv ~subst ~context t2))
+    rc)));
+
   rc
 ;;