Changed logic of entrypoint in Lambda4

- removed exception Fail
- added "check",which checks if we are in a subproblem
  of separation on which we know to be complete
- "solve" does not raise particular exceptions anymore,
  and the program raise failure only if there is some bug

(cherry picked from commit 608c40045f651c6402b17c437f997de4d63f6afd)

diff --git a/ocaml/lambda4.ml b/ocaml/lambda4.ml
index 355380eae032401af3518c89be84acc71a67a1f5..fa9b043e4f64d1b60bed908a2893f83389d4585c 100644 (file)
--- a/ocaml/lambda4.ml
+++ b/ocaml/lambda4.ml
@@ -244,7 +244,7 @@ exception Dangerous
 
 let arity_of arities k =
  let _,pos,y = List.find (fun (v,_,_) -> v=k) arities in
- let arity = match y with `Var _ -> 0 | `I(_,args) -> Listx.length args | _ -> assert false in
+ let arity = match y with `Var _ -> 0 | `I(_,args) -> Listx.length args | `N _ -> assert false in
  arity + if pos = -1 then - 1 else 0
 ;;
 
@@ -663,33 +663,43 @@ let env_of_sigma freshno sigma should_explode =
       else ([],Pure.V n,[]))::e
  in aux 0
 ;;
+(* ************************************************************************** *)
+
+type result = [
+ | `Separable of (int * Num.nf) list
+ | `Unseparable of string
+]
+
+let check p =
+ (* check if there are duplicates in p.ps *)
+ (* FIXME what about initial fragments? *)
+ if (let rec f = function
+     | [] -> false
+     | hd::tl -> List.exists (eta_eq hd) tl || f tl in
+   f p.ps)
+  then Some "ps contains duplicate entries"
+ (* check if div occurs somewhere in ps@conv *)
+ else match p.div with
+  | None -> None
+  | Some div ->
+     if (List.exists (eta_subterm div) (p.ps@p.conv))
+      then Some "div occurs as subterm in ps or conv"
+      else None
+;;
 
-let solve p  =
+let solve p =
+ prerr_endline (string_of_problem "main" p);
+ match check p with
+ | Some s -> `Unseparable s
+ | None ->
  bomb := `Var(-1,-666);
- if List.for_all (function `N _ -> true | _ -> false) p.ps && p.div = None
-  then (prerr_endline "Initial problem is already completed, nothing to do")
-  else (
-  Console.print_hline();
-  prerr_endline (string_of_problem "main" p);
-  let p_finale = auto p p.initialSpecialK in
-  let freshno,sigma = p_finale.freshno, p_finale.sigma in
-  prerr_endline ("------- <DONE> ------ measure=. \n ");
-  (* prerr_endline (string_of_problem "Original problem" p); *)
-  (* prerr_endline "---------------------"; *)
-  let l = Array.to_list (Array.init (freshno + 1) string_of_var) in
-  (* prerr_endline "---------------------"; *)
-  List.iter (fun (x,inst) -> prerr_endline (string_of_var x ^ " := " ^ print ~l inst)) sigma;
-(*
-   prerr_endline "----------------------";
-   let ps =
-    List.fold_left (fun ps (x,inst) ->
-     (* CSC: XXXX Is the subst always sorted correctly? Otherwise, implement a recursive subst *)
-     (* In this non-recursive version, the intermediate states may containt Matchs *)
-     List.map (fun t -> let t = subst false x inst (t :> nf) in cast_to_i_num_var t) ps)
-     (p.ps :> i_num_var list) sigma in
-   prerr_endline (string_of_problem {p with ps= List.map (function t -> cast_to_i_n_var t) ps; freshno});
-   List.iteri (fun i (n,more_args) -> assert (more_args = 0 && n = `N i)) ps ;
-*)
+ Console.print_hline();
+ let p_finale = auto p p.initialSpecialK in
+ let freshno,sigma = p_finale.freshno, p_finale.sigma in
+ prerr_endline ("------- <DONE> ------ measure=. \n ");
+ let l = Array.to_list (Array.init (freshno + 1) string_of_var) in
+ List.iter (fun (x,inst) -> prerr_endline (string_of_var x ^ " := " ^ print ~l inst)) sigma;
+
   prerr_endline "---------<OPT>----------";
   let sigma = optimize_numerals p_finale in (* optimize numerals *)
   let l = Array.to_list (Array.init (freshno + 1) string_of_var) in
@@ -704,17 +714,6 @@ let solve p  =
   let sigma' = List.map (fun (x,inst) -> x, ToScott.t_of_nf inst) sigma in
   let e' = env_of_sigma freshno sigma' false (* FIXME shoudl_explode *) in
 
-(*
-   prerr_endline "---------<PPP>---------";
-let rec print_e e =
-"[" ^ String.concat ";" (List.map (fun (e,t,[]) -> print_e e ^ ":" ^ Pure.print t) e) ^ "]"
-in
-   prerr_endline (print_e e);
-   List.iter (fun (t,t_ok) ->
-    prerr_endline ("T0= " ^ Pure.print t ^ "\nTM= " ^ Pure.print (Pure.unwind (e,t,[])) ^ "\nOM= " ^ Pure.print t_ok);
-    (*assert (Pure.unwind (e,t,[]) = t_ok)*)
-   ) (List.combine ps ps_ok);
-*)
   prerr_endline "--------<REDUCE>---------";
   let pure_bomb = ToScott.t_of_nf (!bomb) in (* Pure.B *)
   (function Some div ->
@@ -735,57 +734,55 @@ in
     verbose ((string_of_int i) ^ ":: " ^ (Pure.print t));
     assert (t = Scott.mk_n i)
   ) ps ;
-  prerr_endline "-------- </DONE> --------"
- )
+  prerr_endline "-------- </DONE> --------";
+  `Separable p_finale.sigma
 ;;
 
-(********************** problems *******************)
-
 let zero = `Var(0,0);;
 
 let append_zero =
  function
   | `I _
-  | `Var _ as i ->  cast_to_i_n_var (mk_app i zero)
-  | _ -> assert false
+  | `Var _ as i -> cast_to_i_n_var (mk_app i zero)
+  | `N _ -> raise (Parser.ParsingError " numbers in ps")
 ;;
 
 let problem_of ~div ~conv ~nums =
  let all_tms = (match div with None -> [] | Some div -> [div]) @ nums @ conv in
  let all_tms, var_names = Parser.parse' all_tms in
-  let div, (tms, conv) = match div with
-    | None -> None, list_cut (List.length nums, all_tms)
-    | Some _ -> Some (List.hd all_tms), list_cut (List.length nums, List.tl all_tms) in
-
- if match div with None -> false | Some div -> List.exists (eta_subterm div) (tms@conv)
- then (
-  prerr_endline "--- TEST SKIPPED ---";
-  {freshno=0; div=None; conv=[]; ps=[]; sigma=[]; deltas=[]; initialSpecialK=0}
- ) else
-  let tms = sort_uniq ~compare:eta_compare tms in
-  let special_k = compute_special_k (Listx.from_list all_tms) in (* compute initial special K *)
-  (* casts *)
-  let div =
-   match div with
-    | None -> None
-    | Some (`I _ as t) -> Some t
-    | _ -> raise (Failure "div is not an inert or BOT in the initial problem") in
-  let conv = Util.filter_map (
-   function
-   | #i_n_var as t -> Some t
-   | `Lam _ -> None
-   | _ -> raise (Failure "A term in conv is not i_n_var")
-   ) conv in
-  let tms = List.map (
-   function
-    | #i_n_var as y -> y
-    | _ -> raise (Failure "A term in num is not i_n_var")
-   ) tms in
-
-  let ps = List.map append_zero tms in (* crea lista applicando zeri o dummies *)
-  let freshno = List.length var_names in
-  let deltas =
-   let dummy = `Var (max_int / 2, -666) in
-    [ ref (Array.to_list (Array.init (List.length ps) (fun i -> i, dummy))) ] in
-  {freshno; div; conv; ps; sigma=[] ; deltas; initialSpecialK=special_k}
+ let div, (ps, conv) = match div with
+   | None -> None, list_cut (List.length nums, all_tms)
+   | Some _ -> Some (List.hd all_tms), list_cut (List.length nums, List.tl all_tms) in
+
+ let div =
+  match div with
+   | None -> None
+   | Some (`I _ as t) -> Some t
+   | _ -> raise (Parser.ParsingError "div is not an inert or BOT in the initial problem") in
+ let conv = Util.filter_map (
+  function
+  | #i_n_var as t -> Some t
+  | `Lam _ -> None
+  | _ -> raise (Parser.ParsingError "A term in conv is not i_n_var")
+  ) conv in
+ let ps = List.map (
+  function
+   | #i_n_var as y -> y
+   | _ -> raise (Parser.ParsingError "A term in num is not i_n_var")
+  ) ps in
+ (* DA SPOSTARE NEI TEST: *)
+ let ps = List.map append_zero ps in (* crea lista applicando zeri o dummies *)
+ let ps = sort_uniq ~compare:eta_compare (ps :> nf list) in
+ let ps = List.map (cast_to_i_n_var) ps in
+
+ (* TODO: *)
+ (* replace div with bottom in problem??? *)
+
+ let special_k = compute_special_k (Listx.from_list all_tms) in (* compute initial special K *)
+ let freshno = List.length var_names in
+ let deltas =
+  let dummy = `Var (max_int / 2, -666) in
+   [ ref (Array.to_list (Array.init (List.length ps) (fun i -> i, dummy))) ] in
+ let p = {freshno; div; conv; ps; sigma=[] ; deltas; initialSpecialK=special_k} in
+ p
 ;;

diff --git a/ocaml/lambda4.mli b/ocaml/lambda4.mli
index 761bef66d19ca262975a141c82bb78f3dd297b78..d8148d5399aea9ba3d3ac582506f0dea47eace94 100644 (file)
--- a/ocaml/lambda4.mli
+++ b/ocaml/lambda4.mli
@@ -1,3 +1,9 @@
 type problem\r
+\r
+type result = [\r
+ | `Separable of (int * Num.nf) list\r
+ | `Unseparable of string\r
+]\r
+\r
 val problem_of: div:(string option) -> conv:string list -> nums:string list -> problem\r
-val solve: problem -> unit\r
+val solve: problem -> result\r

diff --git a/ocaml/num.ml b/ocaml/num.ml
index f612def74371072024552c584be261a8ff01ea69..36234ad31c7a47b15b9af578aab525c379ba5419 100644 (file)
--- a/ocaml/num.ml
+++ b/ocaml/num.ml
@@ -162,6 +162,7 @@ let cast_to_i_num_var =
     assert false (* algorithm failed *)
 
 let rec set_arity arity = function
+(* FIXME because onlt variables should be in branches of matches, one day *)
 | `Var(n,_) -> `Var(n,arity)
 | `N _ as t -> t
 | `Lam(false, t) -> `Lam(false, set_arity arity t)

diff --git a/ocaml/problems.ml b/ocaml/problems.ml
index 7cb068f72485f4e055d9578894ce10b438bcae16..e01a741339652a74cdcbe5497971090d70dc7bda 100644 (file)
--- a/ocaml/problems.ml
+++ b/ocaml/problems.ml
@@ -1,9 +1,37 @@
 open Lambda4;;
-let solve_many = List.iter solve;;
+open Util;;
+
+let assert_separable x =
+ match solve x with
+ | `Separable _ -> ()
+ | `Unseparable s ->
+   failwith ("assert_separable: unseparable because: " ^ s ^ ".")
+;;
+
+let assert_unseparable x =
+ match solve x with
+ | `Unseparable _ -> ()
+ | `Separable _ ->
+   failwith ("assert_unseparable: separable.")
+;;
+
+let solve_many = List.iter assert_separable;;
+
+(* TODO *)
+(* div under a lambda in conv *)
+(* assert_unseparable (problem_of (Some"`y y") ["x (_. y y)"] []);; *)
+
+assert_unseparable (problem_of None [] (* 32 *)
+ ["(((((a y) v) (z a)) (z (((z a) (z a)) (w. v)))) (y. (a y)))";
+ "(((((a y) v) (z a)) (z (((z a) (z a)) (w. v)))) a)";
+ "(((((z a) (z a)) b) (v. (v. (z a)))) (v. ((a y) v)))";
+ "((((a y) v) (z a)) (z (((z a) (z a)) (w. v))))";
+ "((((w (a. (z. ((z a) (z a))))) (v. ((a y) v))) (((z a) (z a)) b)) (w. (((z a) (z a)) (c. (c ((z a) (z a)))))))"
+ ]);;
 
 (* p-series problems *)
-let f x = problem_of None [] x in
-solve_many (List.map f [
+let f x = assert_separable (problem_of None [] x) in
+List.iter f [
  (* 2 *) [ "x y"; "x z" ; "x (y z)"];
  (* 4 *) [ "x y"; "x (a. a x)" ; "y (y z)" ];
  (* 5 *) ["a (x. x a) b"; "b (x. x b) a"];
@@ -70,13 +98,6 @@ solve_many (List.map f [
   "(((((b (a v)) (a. (y c))) z) (w. w)) ((a c) c))";
   "(((((v (((a v) w) (((a v) w) v))) (w. c)) (b (a v))) c) (z. a))";
   "((((a (y c)) ((y c) ((a v) (w (z. a))))) (w. c)) (x. w))"];
- (* 32 *)
-  ["(((((a y) v) (z a)) (z (((z a) (z a)) (w. v)))) (y. (a y)))";
-  "(((((a y) v) (z a)) (z (((z a) (z a)) (w. v)))) a)";
-  "(((((z a) (z a)) b) (v. (v. (z a)))) (v. ((a y) v)))";
-  "((((a y) v) (z a)) (z (((z a) (z a)) (w. v))))";
-  "((((w (a. (z. ((z a) (z a))))) (v. ((a y) v))) (((z a) (z a)) b)) (w. (((z a) (z a)) (c. (c ((z a) (z a)))))))"
-  ];
  (* 33 *)
   (* Shows an error when the strategy that minimizes special_k is NOT used *)
   [ "((((((v (y. v)) (w. (c. y))) ((((a (c. y)) (v w)) ((b (z (a (c. y)))) (b (z (a (c. y)))))) ((a (c. y)) b))) (((y (y (v w))) z) ((((a (c. y)) (v w)) ((b (z (a (c. y)))) (b (z (a (c. y)))))) ((a (c. y)) b)))) (b c)) (((v w) (z (a (c. y)))) ((y b) (b (z (a (c. y)))))))";
@@ -100,8 +121,7 @@ solve_many (List.map f [
   "(((((((z v) (y a)) (b a)) w) b) (a (((((y a) (((z v) (y a)) (b a))) ((b a) (b a))) (x a)) ((((y a) (((z v) (y a)) (b a))) z) (((z v) (y a)) (c y)))))) ((((y a) (((z v) (y a)) (b a))) ((((y a) (((z v) (y a)) (b a))) ((b a) (b a))) (x a))) x))"];
  (* 37 *) (* issue with eta-equality of terms in ps *)
   ["x (a y) z"; "x (a z. y z) w"; "a c"];
-
-]);;
+];;
 
 (* q-series problems *)
 
@@ -130,13 +150,13 @@ let q4 () = problem_of
  ;;
 
 let q5 () = problem_of
- (Some"x")
- ["(y. x)"]
+ (Some"x x")
+ ["x"]
  ["x"]
  ;;
 
 let q6 () = problem_of
- (Some"x")
+ (Some"x x")
  ["(y. x z)"]
  ["y"]
  ;;