X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Fsoftware%2Fcomponents%2Fng_refiner%2FnCicMetaSubst.ml;h=421194abdb02b3a4431149b995e6b7493e104248;hb=dfee894b6cc036014bbbf1f508621840f44144d7;hp=a445d16be4cf6a99a8937c6026c322672454854c;hpb=b873fcd647e7b30e486eac5c5470762c9bc79e93;p=helm.git

diff --git a/helm/software/components/ng_refiner/nCicMetaSubst.ml b/helm/software/components/ng_refiner/nCicMetaSubst.ml
index a445d16be..421194abd 100644
--- a/helm/software/components/ng_refiner/nCicMetaSubst.ml
+++ b/helm/software/components/ng_refiner/nCicMetaSubst.ml
@@ -206,28 +206,46 @@ and restrict metasenv subst i restrictions =
     | NCicUtils.Meta_not_found _ -> assert false
 ;;
 
-let rec flexible_arg subst = function 
-  | NCic.Meta (i,_) | NCic.Appl (NCic.Meta (i,_) :: _)-> 
+let rec flexible_arg context subst = function 
+  | NCic.Meta (i,_) ->
       (try 
         let _,_,t,_ = List.assoc i subst in
-        flexible_arg subst t
+        flexible_arg context subst t
       with Not_found -> true)
+  | NCic.Appl (NCic.Meta (i,_) :: args)-> 
+      (try 
+        let _,_,t,_ = List.assoc i subst in
+        flexible_arg context subst 
+          (NCicReduction.head_beta_reduce ~delta:max_int 
+            (NCic.Appl (t :: args)))
+      with Not_found -> true)
+   (* this is a cheap whd, it only performs zeta-reduction.
+    * 
+    * it works when the **omissis** disambiguation algorithm
+    * is run on `let x := K a b in t`, K is substituted for a 
+    * ? and thus in t metavariables have a flexible Rel
+    *)
+  | NCic.Rel i ->
+      (try
+         match List.nth context (i-1)
+         with 
+         | _,NCic.Def (bo,_) ->
+               flexible_arg context subst
+                 (NCicSubstitution.lift i bo)
+         | _ -> false
+      with 
+      | Failure _ -> 
+          prerr_endline (Printf.sprintf "Rel %d inside context:\n%s" i  
+            (NCicPp.ppcontext ~subst ~metasenv:[] context));
+          assert false
+      | Invalid_argument _ -> assert false)
   | _ -> false
 ;;
 
-let flexible subst l = List.exists (flexible_arg subst) l;;
-
-let in_scope_tag  = "tag:in_scope" ;;
-let out_scope_tag_prefix = "tag:out_scope:" 
-let out_scope_tag n = out_scope_tag_prefix ^ string_of_int n ;;
-let is_out_scope_tag tag =
-   String.length tag > String.length out_scope_tag_prefix &&
-   String.sub tag 0 (String.length out_scope_tag_prefix) = out_scope_tag_prefix 
-;;
+let is_out_scope = function `OutScope _ -> true | _ -> false;;
+let is_out_scope_tag = List.exists is_out_scope;;
 let int_of_out_scope_tag tag = 
-  int_of_string
-   (String.sub tag (String.length out_scope_tag_prefix)
-     (String.length tag - (String.length out_scope_tag_prefix)))
+ match List.filter is_out_scope tag with [`OutScope n] -> n | _ -> assert false
 ;;
 
 
@@ -241,7 +259,7 @@ let delift ~unify metasenv subst context n l t =
     | NCic.Meta (i,_) ->
         (try 
            let tag, _, _, _ = NCicUtils.lookup_subst i subst in 
-           tag = Some in_scope_tag 
+            List.mem `InScope tag
         with NCicUtils.Subst_not_found _ -> false)
     | _ -> false
   in
@@ -256,38 +274,35 @@ let delift ~unify metasenv subst context n l t =
     in
     try aux () () t; false with Found -> true
   in
-  let unify_list ~alpha in_scope = 
+  let unify_list in_scope = 
     match l with
     | _, NCic.Irl _ -> fun _ _ _ _ _ -> None
     | shift, NCic.Ctx l -> fun metasenv subst context k t ->
-       if flexible_arg subst t || contains_in_scope subst t then None else
-         let lb = List.map (fun t -> t, flexible_arg subst t) l in
+       if flexible_arg context subst t || contains_in_scope subst t then None else
+         let lb = 
+           List.map (fun t -> 
+            let t = NCicSubstitution.lift (k+shift) t in
+            t, flexible_arg context subst t) 
+           l 
+         in
          HExtlib.list_findopt
           (fun (li,flexible) i ->
             if flexible || i < in_scope then None else
-             let li = NCicSubstitution.lift (k+shift) li in
-              if alpha then
-               if NCicReduction.alpha_eq metasenv subst context li t then
-                Some ((metasenv,subst), NCic.Rel (i+1+k))
-               else
-                None
-              else
-               match unify metasenv subst context li t with
-               | Some (metasenv,subst) -> 
-                   Some ((metasenv, subst), NCic.Rel (i+1+k))
-               | None -> None)
+             match unify metasenv subst context li t with
+             | Some (metasenv,subst) -> 
+                 Some ((metasenv, subst), NCic.Rel (i+1+k))
+             | None -> None)
           lb
   in
   let rec aux (context,k,in_scope) (metasenv, subst as ms) t = 
-   match unify_list ~alpha:true in_scope metasenv subst context k t with
+   match unify_list in_scope metasenv subst context k t with
    | Some x -> x
    | None -> 
-   try
     match t with 
     | NCic.Rel n as t when n <= k -> ms, t
     | NCic.Rel n -> 
         (try
-          match List.nth context (n-k-1) with
+          match List.nth context (n-1) with
           | _,NCic.Def (bo,_) -> 
                 (try ms, NCic.Rel ((position in_scope (n-k) l) + k)
                  with NotInTheList ->
@@ -307,16 +322,15 @@ let delift ~unify metasenv subst context n l t =
         (try
            let tag,c,t,ty = NCicUtils.lookup_subst i subst in
            let in_scope, clear = 
-             match tag with 
-             | Some tag when tag = in_scope_tag -> 0, true
-             | Some tag when is_out_scope_tag tag->int_of_out_scope_tag tag,true
-             | _ -> in_scope, false
+            if List.mem `InScope tag then 0, true
+            else if is_out_scope_tag tag then int_of_out_scope_tag tag,true
+            else in_scope, false
            in
            let ms = 
              if not clear then ms
              else 
                metasenv, 
-               (i,(None,c,t,ty)) :: List.filter (fun j,_ -> i <> j) subst
+               (i,([],c,t,ty)) :: List.filter (fun j,_ -> i <> j) subst
            in
            aux (context,k,in_scope) ms (NCicSubstitution.subst_meta l1 t)
          with NCicUtils.Subst_not_found _ ->
@@ -413,11 +427,16 @@ let delift ~unify metasenv subst context n l t =
     | t -> 
         NCicUntrusted.map_term_fold_a 
           (fun e (c,k,s) -> (e::c,k+1,s)) (context,k,in_scope) aux ms t
-   with NotInTheList ->
-    match unify_list ~alpha:false in_scope metasenv subst context k t with
-    | Some x -> x
-    | None -> raise NotInTheList
   in
+(*
+  prerr_endline (
+    "DELIFTO " ^ NCicPp.ppterm ~metasenv ~subst ~context t ^ " w.r.t. " ^
+    String.concat ", " (List.map (NCicPp.ppterm ~metasenv ~subst ~context) ( 
+      let shift, lc = l in
+      (List.map (NCicSubstitution.lift shift) 
+        (NCicUtils.expand_local_context lc))
+  )));
+*)
    try aux (context,0,0) (metasenv,subst) t
    with NotInTheList ->
       (* This is the case where we fail even first order unification. *)
@@ -435,33 +454,33 @@ let delift ~unify metasenv subst context n l t =
       let lc = NCicUtils.expand_local_context lc in
       let l = List.map (NCicSubstitution.lift shift) lc in
        if
-        List.exists (fun t-> NCicUntrusted.metas_of_term subst context t = []) l
+        List.exists (fun t-> NCicUntrusted.metas_of_term subst context t <> [])l
        then
         raise (Uncertain msg)
        else
         raise (MetaSubstFailure msg)
 ;;
 
-let mk_meta ?name metasenv context ty = 
-  let tyof = function Some s -> Some ("typeof_"^s) | None -> None in
-  let rec mk_meta name n metasenv context = function
+let mk_meta ?(attrs=[]) metasenv context ty = 
+  let tyof = List.map (function `Name s -> `Name ("typeof_"^s) | x -> x) in
+  let rec mk_meta attrs n metasenv context = function
   | `WithType ty ->
     let len = List.length context in
-    let menv_entry = (n, (name, context, ty)) in
+    let menv_entry = (n, (attrs, context, ty)) in
     menv_entry :: metasenv, n, NCic.Meta (n, (0,NCic.Irl len)), ty
   | `Sort ->
     let ty = NCic.Implicit (`Typeof n) in
-    mk_meta (tyof name) n metasenv [] (`WithType ty)
+    mk_meta (`IsSort::tyof attrs) n metasenv [] (`WithType ty)
   | `Type ->
     let metasenv, _, ty, _ = 
-      mk_meta (tyof name) (newmeta ()) metasenv context `Sort in
-    mk_meta name n metasenv context (`WithType ty)
+      mk_meta (tyof attrs) (newmeta ()) metasenv context `Sort in
+    mk_meta attrs n metasenv context (`WithType ty)
   | `Term ->
     let metasenv, _, ty, _ = 
-      mk_meta (tyof name) (newmeta ()) metasenv context `Type in
-    mk_meta name n metasenv context (`WithType ty)
+      mk_meta (tyof attrs) (newmeta ()) metasenv context `Type in
+    mk_meta attrs n metasenv context (`WithType ty)
   in
-    mk_meta name (newmeta ()) metasenv context ty
+    mk_meta attrs (newmeta ()) metasenv context ty
 ;;
 
 let saturate ?(delta=0) metasenv subst context ty goal_arity =
@@ -469,7 +488,7 @@ let saturate ?(delta=0) metasenv subst context ty goal_arity =
   let rec aux metasenv = function
    | NCic.Prod (name,s,t) as ty ->
        let metasenv1, _, arg,_ = 
-          mk_meta ~name:name metasenv context (`WithType s) in            
+          mk_meta ~attrs:[`Name name] metasenv context (`WithType s) in
        let t, metasenv1, args, pno = 
            aux metasenv1 (NCicSubstitution.subst arg t) 
        in