X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Fsoftware%2Fcomponents%2Fng_refiner%2FnCicRefiner.ml;h=73634e7e0757e2ac3a477cfb0a1b4b092ab4544c;hb=3d16e43756f5e7c7e551e93e003a15c90627b77b;hp=a0324eab2aa0cb63fc2ae01e7ae90b0cd47d268a;hpb=8e65e5eb59904848a24506ffe55323fdcc8bf975;p=helm.git

diff --git a/helm/software/components/ng_refiner/nCicRefiner.ml b/helm/software/components/ng_refiner/nCicRefiner.ml
index a0324eab2..73634e7e0 100644
--- a/helm/software/components/ng_refiner/nCicRefiner.ml
+++ b/helm/software/components/ng_refiner/nCicRefiner.ml
@@ -22,12 +22,14 @@ let indent = ref "";;
 let inside c = indent := !indent ^ String.make 1 c;;
 let outside () = indent := String.sub !indent 0 (String.length !indent -1);;
 
+
 (*
 let pp s = 
   prerr_endline (Printf.sprintf "%-20s" !indent ^ " " ^ Lazy.force s)
 ;;  
 *)
 
+
 let pp _ = ();;
 
 let wrap_exc msg = function
@@ -46,56 +48,8 @@ let exp_implicit metasenv context expty =
   | _ -> assert false
 ;;
 
-let force_to_sort metasenv subst context orig localise t =
-  match NCicReduction.whd ~subst context t with
-  | C.Meta (_,(0,(C.Irl 0 | C.Ctx []))) as t -> 
-     metasenv, subst, t
-  | C.Meta (i,(_,(C.Irl 0 | C.Ctx []))) -> 
-     metasenv, subst, C.Meta(i,(0,C.Irl 0))
-  | C.Meta (i,(_,lc)) ->
-     let len = match lc with C.Irl len->len | C.Ctx l->List.length l in
-     let metasenv, subst, newmeta = 
-       if len > 0 then
-         NCicMetaSubst.restrict metasenv subst i (HExtlib.list_seq 1 (len+1)) 
-       else metasenv, subst, i
-     in
-     metasenv, subst, C.Meta (newmeta,(0,C.Irl 0))
-  | C.Sort _ as t -> metasenv, subst, t 
-  | t -> 
-      raise (RefineFailure (lazy 
-        (localise orig, 
-        "Not a sort: " ^ 
-        NCicPp.ppterm ~metasenv ~subst ~context t)))
-;;
-
-let sort_of_prod 
-  localise metasenv subst context orig_s orig_t (name,s) t (t1, t2) 
-=
-   let metasenv, subst, t1 = 
-     force_to_sort metasenv subst context orig_s localise t1 in
-   let metasenv, subst, t2 = 
-     force_to_sort metasenv subst ((name,C.Decl s)::context) 
-       orig_t localise t2 in
-   match t1, t2 with
-   | C.Sort _, C.Sort C.Prop -> metasenv, subst, t2
-   | C.Sort (C.Type u1), C.Sort (C.Type u2) ->
-        metasenv, subst, C.Sort (C.Type (u1@u2)) 
-   | C.Sort C.Prop,C.Sort (C.Type _) -> metasenv, subst, t2
-   | C.Meta _, C.Sort _ 
-   | C.Meta _, C.Meta (_,(_,_))
-   | C.Sort _, C.Meta (_,(_,_)) -> metasenv, subst, t2 
-   | x, (C.Sort _ | C.Meta _) | _, x -> 
-      let y, context, orig = 
-        if x == t1 then s, context, orig_s 
-        else t, ((name,C.Decl s)::context), orig_t
-      in
-      raise (RefineFailure (lazy (localise orig,Printf.sprintf
-        "%s is expected to be a type, but its type is %s that is not a sort" 
-         (NCicPp.ppterm ~subst ~metasenv ~context y) 
-         (NCicPp.ppterm ~subst ~metasenv ~context x))))
-;;
 
-let check_allowed_sort_elimination localise r orig =
+let check_allowed_sort_elimination hdb localise r orig =
    let mkapp he arg =
      match he with
      | C.Appl l -> C.Appl (l @ [arg])
@@ -113,7 +67,7 @@ let check_allowed_sort_elimination localise r orig =
           NCicMetaSubst.mk_meta metasenv ((name,C.Decl so1)::context) `Type 
         in
         let metasenv, subst = 
-          try NCicUnification.unify metasenv subst context 
+          try NCicUnification.unify hdb metasenv subst context 
                 arity2 (C.Prod (name, so1, meta)) 
           with exc -> raise (wrap_exc (lazy (localise orig, Printf.sprintf
             "expected %s, found %s" (* XXX localizzare meglio *)
@@ -125,7 +79,7 @@ let check_allowed_sort_elimination localise r orig =
      | C.Sort _ (* , t ==?== C.Prod _ *) ->
         let metasenv, meta, _ = NCicMetaSubst.mk_meta metasenv [] `Type in
         let metasenv, subst = 
-          try NCicUnification.unify metasenv subst context 
+          try NCicUnification.unify hdb metasenv subst context 
                 arity2 (C.Prod ("_", ind, meta)) 
           with exc -> raise (wrap_exc (lazy (localise orig, Printf.sprintf
             "expected %s, found %s" (* XXX localizzare meglio *)
@@ -143,29 +97,29 @@ let check_allowed_sort_elimination localise r orig =
     aux
 ;;
 
-let rec typeof 
-  ?(localise=fun _ -> Stdpp.dummy_loc) metasenv subst context term expty 
+let rec typeof hdb 
+  ?(localise=fun _ -> Stdpp.dummy_loc) 
+  ~look_for_coercion metasenv subst context term expty 
 =
-  let force_ty metasenv subst context orig t infty expty =
+  let force_ty skip_lambda metasenv subst context orig t infty expty =
     (*D*)inside 'F'; try let rc = 
     match expty with
     | Some expty ->
        (match t with
-       | C.Implicit _ 
-       | C.Lambda _ -> metasenv, subst, t, expty
+       | C.Implicit _ -> assert false
+       | C.Lambda _ when skip_lambda -> metasenv, subst, t, expty
        | _ ->
           pp (lazy (
           (NCicPp.ppterm ~metasenv ~subst ~context infty) ^  " === " ^
           (NCicPp.ppterm ~metasenv ~subst ~context expty)));
-         let metasenv, subst = 
-           try NCicUnification.unify metasenv subst context infty expty
-           with exc -> raise (wrap_exc (lazy (localise orig, Printf.sprintf
-             "The term %s has type %s but is here used with type %s"
-             (NCicPp.ppterm ~metasenv ~subst ~context t)
-             (NCicPp.ppterm ~metasenv ~subst ~context infty)
-             (NCicPp.ppterm ~metasenv ~subst ~context expty))) exc)
-         in
-         metasenv, subst, t, expty)
+           try 
+             let metasenv, subst =
+               NCicUnification.unify hdb metasenv subst context infty expty 
+             in
+             metasenv, subst, t, expty
+           with exc -> 
+             try_coercions hdb ~look_for_coercion ~localise 
+               metasenv subst context t orig infty expty true exc)
     | None -> metasenv, subst, t, infty
     (*D*)in outside(); rc with exc -> outside (); raise exc
   in
@@ -210,47 +164,58 @@ let rec typeof
        metasenv, subst, t, NCicTypeChecker.typeof ~subst ~metasenv context t
     | C.Prod (name,(s as orig_s),(t as orig_t)) ->
        let metasenv, subst, s, s1 = typeof_aux metasenv subst context None s in
+       let metasenv, subst, s, s1 = 
+         force_to_sort hdb ~look_for_coercion
+           metasenv subst context s orig_s localise s1 in
        let context1 = (name,(C.Decl s))::context in
        let metasenv, subst, t, s2 = typeof_aux metasenv subst context1 None t in
-       let metasenv, subst, ty = 
+       let metasenv, subst, t, s2 = 
+         force_to_sort hdb ~look_for_coercion
+           metasenv subst context1 t orig_t localise s2 in
+       let metasenv, subst, s, t, ty = 
          sort_of_prod localise metasenv subst 
            context orig_s orig_t (name,s) t (s1,s2)
        in
        metasenv, subst, NCic.Prod(name,s,t), ty
-    | C.Lambda (n,(s as orig_s),t) ->
-       let exp_s, exp_ty_t =
+    | C.Lambda (n,(s as orig_s),t) as orig ->
+       let exp_s, exp_ty_t, force_after =
          match expty with
-         | None -> None, None
+         | None -> None, None, false
          | Some expty -> 
              match NCicReduction.whd ~subst context expty with
-             | C.Prod (_,s,t) -> Some s, Some t
-             | _ -> None, None
+             | C.Prod (_,s,t) -> Some s, Some t, false
+             | _ -> None, None, true 
        in
        let metasenv, subst, s, ty_s = 
          typeof_aux metasenv subst context None s in
-       let metasenv, subst, _ = 
-         force_to_sort metasenv subst context orig_s localise ty_s in
+       let metasenv, subst, s, _ = 
+         force_to_sort hdb ~look_for_coercion
+           metasenv subst context s orig_s localise ty_s in
        let (metasenv,subst), exp_ty_t = 
          match exp_s with 
          | Some exp_s -> 
-             (try NCicUnification.unify metasenv subst context s exp_s,exp_ty_t
+             (try NCicUnification.unify hdb metasenv subst context s exp_s,exp_ty_t
              with exc -> raise (wrap_exc (lazy (localise orig_s, Printf.sprintf
                "Source type %s was expected to be %s" (NCicPp.ppterm ~metasenv
                ~subst ~context s) (NCicPp.ppterm ~metasenv ~subst ~context
                exp_s))) exc))
          | None -> (metasenv, subst), None
        in
-       (* XXX coerce_to_sort s *)
-       let context = (n,C.Decl s) :: context in
+       let context_for_t = (n,C.Decl s) :: context in
        let metasenv, subst, t, ty_t = 
-         typeof_aux metasenv subst context exp_ty_t t 
+         typeof_aux metasenv subst context_for_t exp_ty_t t 
        in
-       metasenv, subst, C.Lambda(n,s,t), C.Prod (n,s,ty_t)
+       if force_after then
+         force_ty false metasenv subst context orig 
+           (C.Lambda(n,s,t)) (C.Prod (n,s,ty_t)) expty
+       else 
+         metasenv, subst, C.Lambda(n,s,t), C.Prod (n,s,ty_t)
     | C.LetIn (n,(ty as orig_ty),t,bo) ->
        let metasenv, subst, ty, ty_ty = 
          typeof_aux metasenv subst context None ty in
-       let metasenv, subst, _ = 
-         force_to_sort metasenv subst context orig_ty localise ty_ty in
+       let metasenv, subst, ty, _ = 
+         force_to_sort hdb ~look_for_coercion
+           metasenv subst context ty orig_ty localise ty_ty in
        let metasenv, subst, t, _ = 
          typeof_aux metasenv subst context (Some ty) t in
        let context1 = (n, C.Def (t,ty)) :: context in
@@ -262,7 +227,8 @@ let rec typeof
     | C.Appl ((he as orig_he)::(_::_ as args)) ->
        let metasenv, subst, he, ty_he = 
          typeof_aux metasenv subst context None he in
-       eat_prods localise metasenv subst context orig_he he ty_he args
+       eat_prods hdb ~localise ~look_for_coercion 
+         metasenv subst context orig_he he ty_he args
    | C.Appl _ -> raise (AssertFailure (lazy "Appl of length < 2"))
    | C.Match (Ref.Ref (_,Ref.Ind (_,tyno,_)) as r,
           outtype,(term as orig_term),pl) as orig ->
@@ -270,7 +236,7 @@ let rec typeof
       let _, _, arity, cl = List.nth itl tyno in
       let constructorsno = List.length cl in
       let _, metasenv, args = 
-        NCicMetaSubst.saturate metasenv context arity 0 in
+        NCicMetaSubst.saturate metasenv subst context arity 0 in
       let ind = if args = [] then C.Const r else C.Appl (C.Const r::args) in
       let metasenv, subst, term, _ = 
         typeof_aux metasenv subst context (Some ind) term in
@@ -284,7 +250,7 @@ let rec typeof
       let metasenv, subst, ind, ind_ty = 
         typeof_aux metasenv subst context None ind in
       let metasenv, subst = 
-         check_allowed_sort_elimination localise r orig_term metasenv subst 
+         check_allowed_sort_elimination hdb localise r orig_term metasenv subst 
            context ind ind_ty outsort 
       in
       (* let's check if the type of branches are right *)
@@ -321,38 +287,136 @@ let rec typeof
     in
     pp (lazy (NCicPp.ppterm ~metasenv ~subst ~context t ^ " :: "^
          NCicPp.ppterm ~metasenv ~subst ~context infty ));
-      force_ty metasenv subst context orig t infty expty
+      force_ty true metasenv subst context orig t infty expty
     (*D*)in outside(); rc with exc -> outside (); raise exc
   in
     typeof_aux metasenv subst context expty term
 
-and eat_prods localise metasenv subst context orig_he he ty_he args =
+and try_coercions hdb 
+  ~localise ~look_for_coercion 
+  metasenv subst context t orig_t infty expty perform_unification exc 
+=
+  (* we try with a coercion *)
+  let rec first exc = function
+  | [] ->         
+      raise (wrap_exc (lazy (localise orig_t, Printf.sprintf
+        "The term %s has type %s but is here used with type %s"
+        (NCicPp.ppterm ~metasenv ~subst ~context t)
+        (NCicPp.ppterm ~metasenv ~subst ~context infty)
+        (NCicPp.ppterm ~metasenv ~subst ~context expty))) exc)
+  | (metasenv, newterm, newtype, meta)::tl ->
+      try 
+          pp (lazy ( "UNIFICATION in CTX:\n"^ 
+            NCicPp.ppcontext ~metasenv ~subst context
+            ^ "\nMENV: " ^
+            NCicPp.ppmetasenv metasenv ~subst
+            ^ "\nOF: " ^
+            NCicPp.ppterm ~metasenv ~subst ~context meta ^  " === " ^
+            NCicPp.ppterm ~metasenv ~subst ~context t ^ "\n"));
+        let metasenv, subst = 
+          NCicUnification.unify hdb metasenv subst context meta t
+        in
+          pp (lazy ( "UNIFICATION in CTX:\n"^ 
+            NCicPp.ppcontext ~metasenv ~subst context
+            ^ "\nMENV: " ^
+            NCicPp.ppmetasenv metasenv ~subst
+            ^ "\nOF: " ^
+            NCicPp.ppterm ~metasenv ~subst ~context newtype ^  " === " ^
+            NCicPp.ppterm ~metasenv ~subst ~context expty ^ "\n"));
+        let metasenv, subst = 
+          if perform_unification then
+            NCicUnification.unify hdb metasenv subst context newtype expty
+          else metasenv, subst
+        in
+        metasenv, subst, newterm, newtype
+      with 
+      | NCicUnification.UnificationFailure _ -> first exc tl
+      | NCicUnification.Uncertain _ as exc -> first exc tl
+  in 
+    first exc
+      (look_for_coercion metasenv subst context infty expty)
+
+and force_to_sort hdb 
+  ~look_for_coercion metasenv subst context t orig_t localise ty 
+=
+  match NCicReduction.whd ~subst context ty with
+  | C.Meta (_,(0,(C.Irl 0 | C.Ctx []))) as ty -> 
+     metasenv, subst, t, ty
+  | C.Meta (i,(_,(C.Irl 0 | C.Ctx []))) -> 
+     metasenv, subst, t, C.Meta(i,(0,C.Irl 0))
+  | C.Meta (i,(_,lc)) ->
+     let len = match lc with C.Irl len->len | C.Ctx l->List.length l in
+     let metasenv, subst, newmeta = 
+       if len > 0 then
+         NCicMetaSubst.restrict metasenv subst i (HExtlib.list_seq 1 (len+1)) 
+       else metasenv, subst, i
+     in
+     metasenv, subst, t, C.Meta (newmeta,(0,C.Irl 0))
+  | C.Sort _ as ty -> metasenv, subst, t, ty 
+  | ty -> 
+      try_coercions hdb ~localise ~look_for_coercion metasenv subst context
+        t orig_t ty (NCic.Sort (NCic.Type NCicEnvironment.type0)) false 
+         (Uncertain (lazy (localise orig_t, 
+         "The type of " ^ NCicPp.ppterm ~metasenv ~subst ~context t
+         ^ " is not a sort: " ^ NCicPp.ppterm ~metasenv ~subst ~context ty)))
+
+and sort_of_prod 
+  localise metasenv subst context orig_s orig_t (name,s) t (t1, t2) 
+=
+   (* force to sort is done in the Prod case in typeof *)
+   match t1, t2 with
+   | C.Sort _, C.Sort C.Prop -> metasenv, subst, s, t, t2
+   | C.Sort (C.Type u1), C.Sort (C.Type u2) ->
+        metasenv, subst, s, t, C.Sort (C.Type (NCicEnvironment.max u1 u2)) 
+   | C.Sort C.Prop,C.Sort (C.Type _) -> metasenv, subst, s, t, t2
+   | C.Meta _, C.Sort _ 
+   | C.Meta _, C.Meta (_,(_,_))
+   | C.Sort _, C.Meta (_,(_,_)) -> metasenv, subst, s, t, t2 
+   | x, (C.Sort _ | C.Meta _) | _, x -> 
+      let y, context, orig = 
+        if x == t1 then s, context, orig_s 
+        else t, ((name,C.Decl s)::context), orig_t
+      in
+      raise (RefineFailure (lazy (localise orig,Printf.sprintf
+        "%s is expected to be a type, but its type is %s that is not a sort" 
+         (NCicPp.ppterm ~subst ~metasenv ~context y) 
+         (NCicPp.ppterm ~subst ~metasenv ~context x))))
+
+and eat_prods hdb
+  ~localise ~look_for_coercion metasenv subst context orig_he he ty_he args 
+=
   (*D*)inside 'E'; try let rc = 
-  let rec aux metasenv subst args_so_far ty_he = function 
-  | [] -> metasenv, subst, NCic.Appl (he :: List.rev args_so_far), ty_he
+  let rec aux metasenv subst args_so_far he ty_he = function 
+  | []->metasenv, subst, NCicUntrusted.mk_appl he (List.rev args_so_far), ty_he
   | arg::tl ->
       match NCicReduction.whd ~subst context ty_he with 
       | C.Prod (_,s,t) ->
           let metasenv, subst, arg, _ = 
-            typeof ~localise metasenv subst context arg (Some s) in
+            typeof hdb ~look_for_coercion ~localise 
+              metasenv subst context arg (Some s) in
           let t = NCicSubstitution.subst ~avoid_beta_redexes:true arg t in
-          aux metasenv subst (arg :: args_so_far) t tl
+          aux metasenv subst (arg :: args_so_far) he t tl
       | C.Meta _
       | C.Appl (C.Meta _ :: _) as t ->
           let metasenv, subst, arg, ty_arg = 
-            typeof ~localise metasenv subst context arg None in
+            typeof hdb ~look_for_coercion ~localise 
+              metasenv subst context arg None in
           let metasenv, meta, _ = 
             NCicMetaSubst.mk_meta metasenv 
               (("_",C.Decl ty_arg) :: context) `Type
           in
           let flex_prod = C.Prod ("_", ty_arg, meta) in
+          (* next line grants that ty_args is a type *)
+          let metasenv,subst, flex_prod, _ =
+           typeof hdb ~look_for_coercion ~localise metasenv subst
+            context flex_prod None in
           pp (lazy ( "UNIFICATION in CTX:\n"^ 
             NCicPp.ppcontext ~metasenv ~subst context
             ^ "\nOF: " ^
             NCicPp.ppterm ~metasenv ~subst ~context t ^  " === " ^
             NCicPp.ppterm ~metasenv ~subst ~context flex_prod ^ "\n"));
           let metasenv, subst = 
-             try NCicUnification.unify metasenv subst context t flex_prod 
+             try NCicUnification.unify hdb metasenv subst context t flex_prod 
              with exc -> raise (wrap_exc (lazy (localise orig_he, Printf.sprintf
               ("The term %s has an inferred type %s, but is applied to the" ^^
                " argument %s of type %s")
@@ -363,7 +427,7 @@ and eat_prods localise metasenv subst context orig_he he ty_he args =
               (* XXX coerce to funclass *)
           in
           let meta = NCicSubstitution.subst ~avoid_beta_redexes:true arg meta in
-          aux metasenv subst (arg :: args_so_far) meta tl
+          aux metasenv subst (arg :: args_so_far) he meta tl
       | C.Match (_,_,C.Meta _,_) 
       | C.Match (_,_,C.Appl (C.Meta _ :: _),_) 
       | C.Appl (C.Const (NReference.Ref (_, NReference.Fix _)) :: _) ->
@@ -371,13 +435,20 @@ and eat_prods localise metasenv subst context orig_he he ty_he args =
             ("The term %s is here applied to %d arguments but expects " ^^
             "only %d arguments") (NCicPp.ppterm ~metasenv ~subst ~context he)
             (List.length args) (List.length args_so_far))))
-      | _ ->
-          raise (RefineFailure (lazy (localise orig_he, Printf.sprintf
-            ("The term %s is here applied to %d arguments but expects " ^^
-            "only %d arguments") (NCicPp.ppterm ~metasenv ~subst ~context he)
-            (List.length args) (List.length args_so_far))))
+      | ty ->
+          let metasenv, subst, newhead, newheadty = 
+            try_coercions hdb ~localise ~look_for_coercion metasenv subst context
+              (NCicUntrusted.mk_appl he (List.rev args_so_far)) orig_he ty
+              (NCic.Prod ("_",NCic.Implicit `Term,NCic.Implicit `Term))
+              false
+              (RefineFailure (lazy (localise orig_he, Printf.sprintf
+               ("The term %s is here applied to %d arguments but expects " ^^
+               "only %d arguments") (NCicPp.ppterm ~metasenv ~subst ~context he)
+               (List.length args) (List.length args_so_far))))
+          in
+          aux metasenv subst [] newhead newheadty (arg :: tl)
   in
-   aux metasenv subst [] ty_he args
+   aux metasenv subst [] he ty_he args
   (*D*)in outside(); rc with exc -> outside (); raise exc
 ;;
 (* vim:set foldmethod=marker: *)