X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=ocaml%2Fnum.ml;h=66bdd8598f0d3ced253a46bce4d66ac2088080bd;hb=9ad3734756bdab9ea23884a7bddbfaa599dbd3ae;hp=d59d07f49f529f40eb39160acd2d5c313427c8cf;hpb=6895644003c1c199f1a43d300b04a975959024e8;p=fireball-separation.git

diff --git a/ocaml/num.ml b/ocaml/num.ml
index d59d07f..66bdd85 100644
--- a/ocaml/num.ml
+++ b/ocaml/num.ml
@@ -2,6 +2,9 @@ open Util
 open Util.Vars
 open Pure
 
+(* debug options *)
+let debug_display_arities = false;;
+
 (************ Syntax ************************************)
 
 (* Normal forms*)
@@ -70,12 +73,12 @@ let rec make_lams t =
  | n when n > 0 -> `Lam (false, lift 1 (make_lams t (n-1)))
  | _ -> assert false
 
-let free_vars =
+let free_vars' =
  let rec aux n = function
     `N _ -> []
-  | `Var(x,_) -> if x < n then [] else [x-n]
-  | `I((x,_),args) ->
-      (if x < n then [] else [x-n]) @
+  | `Var(x,ar) -> if x < n then [] else [(x-n,ar)]
+  | `I((x,ar),args) ->
+      (if x < n then [] else [(x-n,ar)]) @
       List.concat (List.map (aux n) (Listx.to_list args))
   | `Lam(_,t) -> aux (n+1) t
   | `Match(t,_,liftno,bs,args) ->
@@ -84,6 +87,7 @@ let free_vars =
       List.concat (List.map (aux n) args)
   in aux 0
 ;;
+let free_vars = (List.map fst) ++ free_vars';;
 
 module ToScott =
 struct
@@ -108,27 +112,34 @@ end
 
 (************ Pretty-printing ************************************)
 
-let rec string_of_term l =
- let rec string_of_term_w_pars l = function
-  | `Var(n,ar) -> print_name l n ^ ":" ^ string_of_int ar
+(* let rec string_of_term l  = fun _ -> "";; *)
+
+let rec string_of_term =
+ let boundvar x = "v" ^ string_of_int x in
+ let varname lev l n =
+  if n < lev then boundvar (lev-n-1)
+   else if n < List.length l then List.nth l (n-lev)
+    else "`" ^ string_of_int (n-lev) in
+ let rec string_of_term_w_pars lev l  = function
+  | `Var(n,ar) -> varname lev l n ^ (if debug_display_arities then ":" ^ string_of_int ar else "")
   | `N n -> string_of_int n
-  | `I _ as t -> "(" ^ string_of_term_no_pars_app l (t :> nf) ^ ")"
-  | `Lam _ as t -> "(" ^ string_of_term_no_pars_lam l t ^ ")"
-  | `Match(t,_,bs_lift,bs,args) ->
-     "(match " ^ string_of_term_no_pars l (t :> nf) ^
-     " with " ^ String.concat " | " (List.map (fun (n,t) -> string_of_int n ^ " => " ^ string_of_term l (lift bs_lift t)) !bs) ^ "] " ^
-     String.concat " " (List.map (string_of_term l) args) ^ ")"
- and string_of_term_no_pars_app l = function
-  | `I((n,ar), args) -> print_name l n  ^ ":" ^ string_of_int ar ^ " " ^ String.concat " " (List.map (string_of_term_w_pars l) (Listx.to_list args))
-  | #nf as t -> string_of_term_w_pars l t
- and string_of_term_no_pars_lam l  = function
-  | `Lam(_,t) -> let name = string_of_var (List.length l) in
-   "λ" ^ name ^ ". " ^ (string_of_term_no_pars_lam (name::l) t)
-  | _ as t -> string_of_term_no_pars l t
- and string_of_term_no_pars l : nf -> string = function
-  | `Lam _ as t -> string_of_term_no_pars_lam l t
-  | #nf as t -> string_of_term_no_pars_app l t
- in string_of_term_no_pars l
+  | `I _ as t -> "(" ^ string_of_term_no_pars_app lev l t ^ ")"
+  | `Lam _ as t -> "(" ^ string_of_term_no_pars_lam lev l t ^ ")"
+  | `Match(t,(v,ar),bs_lift,bs,args) ->
+      (* assert (bs_lift = lev); *)
+     "(["^ varname 0 l v ^ (if debug_display_arities then ":"^ string_of_int ar else "") ^",match " ^ string_of_term_no_pars lev l (t :> nf) ^
+     " with " ^ String.concat " | " (List.map (fun (n,t) -> string_of_int n ^ " => " ^ string_of_term l (t :> nf)) !bs) ^ "] " ^
+     String.concat " " (List.map (string_of_term l) (args :> nf list)) ^ ")"
+ and string_of_term_no_pars_app lev l  = function
+  | `I((n,ar), args) -> varname lev l n ^ (if debug_display_arities then ":" ^ string_of_int ar else "") ^ " " ^ String.concat " " (List.map (string_of_term_w_pars lev l) (Listx.to_list args :> nf list))
+  | #nf as t -> string_of_term_w_pars lev l t
+ and string_of_term_no_pars_lam lev l  = function
+  | `Lam(_,t) -> "λ" ^ boundvar lev ^ ". " ^ (string_of_term_no_pars_lam (lev+1) l t)
+  | _ as t -> string_of_term_no_pars lev l t
+ and string_of_term_no_pars lev l = function
+  | `Lam _ as t -> string_of_term_no_pars_lam lev l t
+  | #nf as t -> string_of_term_no_pars_app lev l t
+ in string_of_term_no_pars 0
 ;;
 
 let print ?(l=[]) = string_of_term l;;
@@ -157,12 +168,13 @@ let cast_to_i_num_var =
     prerr_endline (print (t :> nf));
     assert false (* algorithm failed *)
 
-let set_arity arity = function
+let rec set_arity arity = function
+(* FIXME because onlt variables should be in branches of matches, one day *)
 | `Var(n,_) -> `Var(n,arity)
-| `Lam(false, `N _)
-| `Lam(false, `Lam _) as t -> t
-| `Lam(false, `Match(t,(n,_),bs_lift,bs,args)) -> `Lam(false, `Match(t,(n,arity),bs_lift,bs,args))
-| _ -> assert false
+| `N _ as t -> t
+| `Lam(false, t) -> `Lam(false, set_arity arity t)
+| `Match(t,(n,_),bs_lift,bs,args) -> `Match(t,(n,arity),bs_lift,bs,args)
+| `I _ | `Lam _ -> assert false
 
 let minus1 n = if n = min_int then n else n - 1;;
 
@@ -197,10 +209,11 @@ and mk_match t (n,ar) bs_lift bs args =
   | `I _ | `Var _ | `Match _ -> `Match(t,(n,ar),bs_lift,bs,args)
 
 and subst truelam delift_by_one what (with_what : nf) (where : nf) =
- let aux_propagate_arity ar = function
- | `Lam(false,`Match(`I(v,args),(x,_),liftno,bs,args')) when not delift_by_one ->
-    `Lam(false,`Match(`I(v,args),(x,ar),liftno,bs,args'))
- | `Var(i,_) -> `Var(i,ar)
+ let rec aux_propagate_arity ar = function
+ | `Lam(false, t) when not delift_by_one -> `Lam(false, aux_propagate_arity ar t)
+ | `Match(`I(v,args),(x,_),liftno,bs,args') when not delift_by_one ->
+    `Match(`I(v,args),(x,ar),liftno,bs,args')
+ | `Var(i,oldar) -> `Var(i, if truelam then (assert (oldar = min_int); ar) else oldar)
  | _ as t -> t in
  let rec aux_i_num_var l =
   function
@@ -217,12 +230,16 @@ and subst truelam delift_by_one what (with_what : nf) (where : nf) =
    | `N _ as x -> x
    | `Match(t,v,bs_lift,bs,args) ->
        let bs_lift = bs_lift + if delift_by_one then -1 else 0 in
+       (* Warning! It now applies again the substitution in branches of matches.
+          But careful, it does it many times, for every occurrence of
+          the match. This is okay because what does not occur in with_what. *)
        let l' = l - bs_lift  in
-       let with_what' = lift l' with_what in
+       let with_what' = lift l' (with_what :> nf) in
        (* The following line should be the identity when delift_by_one = true because we
           are assuming the ts to not contain lambda-bound variables. *)
        bs := List.map (fun (n,t) -> n,subst truelam false what with_what' t) !bs ;
-       mk_match (cast_to_i_num_var (aux_i_num_var l t)) v bs_lift bs (List.map (aux l) args)
+       let body = cast_to_i_num_var (aux_i_num_var l t) in
+       mk_match body v bs_lift bs (List.map (aux l) (args :> nf list))
  and aux l(*lift*) =
 (*function iii -> let res = match iii with*)
   function
@@ -234,20 +251,6 @@ prerr_endline ("subst l:" ^ string_of_int l ^ " delift_by_one:" ^ string_of_bool
   aux 0 where
 ;;
 
-(************ Parsing ************************************)
-
-let parse' strs =
-  let fix_arity = function
-  | `I((n,_),args) -> `I((n,1+Listx.length args),args)
-  | _ -> assert false in
-  let rec aux = function
-  | Parser.Lam t -> `Lam (true, aux t)
-  | Parser.App (t1, t2) -> fix_arity (mk_app (aux t1) (aux t2))
-  | Parser.Var v -> `Var(v,1) in
-  let (tms, free) = Parser.parse_many strs in
-  List.map aux tms, free
-;;
-
 (************** Algorithm(s) ************************)
 
 let eta_compare x y =
@@ -292,10 +295,10 @@ let rec eta_subterm sub t =
   | `Match(u,ar,liftno,bs,args) ->
      eta_subterm sub (u :> nf)
      || List.exists (fun (_, t) -> eta_subterm sub (lift liftno t)) !bs
-     || List.exists (eta_subterm sub) args
-  | `I(v, args) -> List.exists (eta_subterm sub) (Listx.to_list args) || (match sub with
-   | `Var v' -> v = v'
-   | `I(v', args') -> v = v'
+     || List.exists (eta_subterm sub) (args :> nf list)
+  | `I((v,_), args) -> List.exists (eta_subterm sub) ((Listx.to_list args) :> nf list) || (match sub with
+   | `Var(v',_) -> v = v'
+   | `I((v',_), args') -> v = v'
     && Listx.length args' < Listx.length args
     && List.for_all (fun (x,y) -> eta_eq x y) (List.combine (Util.take (Listx.length args') (Listx.to_list args)) (Listx.to_list args'))
    | _ -> false
@@ -320,7 +323,7 @@ let max_arity_tms n =
   | `Match(u,_,_,bs,args) -> max (max (aux l (u :> nf)) (aux_tms l args)) (aux_tms l (List.map snd !bs))
   | `N _ -> None
  and aux_tms l =
-  List.fold_left (fun acc t -> Pervasives.max acc (aux l t)) None in
+  List.fold_left (fun acc t -> max acc (aux l t)) None in
  fun tms -> aux_tms 0 (tms :> nf list)
 ;;