open Pure
open Num
-let bomb = ref(`Var(-1,-666));;
-
(*
The number of arguments which can applied to numbers
safely, depending on the encoding of numbers.
For Scott's encoding, two.
*)
let num_more_args = 2;;
+let _very_verbose = false;;
+
+let verbose s =
+ if _very_verbose then prerr_endline s
+;;
+
+let convergent_dummy = `N(-1);;
type discriminating_set = (int * nf) list;;
; trail: discriminating_set list list
};;
+(* exceptions *)
+exception Pacman
+exception Bottom
exception Backtrack of string
+exception Fail of string
let first bound p var f =
let p = {p with trail = (List.map (!) p.deltas)::p.trail} in
raise (Backtrack ("no more alternatives for " ^ string_of_var var))
else
try
- f p i
- with
- Backtrack s ->
-prerr_endline ("!!BACKTRACK!! " ^ s);
+ f p i
+ with Backtrack s ->
+prerr_endline (">>>>>> BACKTRACK (reason: " ^ s ^") measure=$ ");
List.iter (fun (r,l) -> r := l) (List.combine p.deltas (List.hd p.trail)) ;
prerr_endline("Now trying var="^string_of_var var^" i="^string_of_int i);
aux (i+1)
let string_of_problem label ({freshno; div; conv; ps; deltas} as p) =
Console.print_hline ();
- prerr_endline ("\n||||| Displaying problem: " ^ label ^ " |||||");
- let nl = "\n " in
- let deltas = String.concat nl (List.map (fun r -> String.concat " <> " (List.map (fun (i,_) -> string_of_int i) !r)) deltas) in
+ prerr_string ("\n(* DISPLAY PROBLEM (" ^ label ^ ") - ");
+ let nl = "\n" in
+ let deltas = String.concat (nl^" ") (List.map (fun r -> String.concat " <> " (List.map (fun (i,_) -> string_of_int i) !r)) deltas) in
let l = Array.to_list (Array.init (freshno + 1) string_of_var) in
- nl ^ "measure="^string_of_measure(problem_measure p)^" freshno = " ^ string_of_int freshno
- ^nl^"\b> DISCRIMINATING SETS (deltas)"
- ^nl^"(*"^deltas^(if deltas = "" then "" else "*)"^nl)
- ^"\b (* DIVERGENT *)" ^ nl
- ^" "^ (match div with None -> "None" | Some div -> "(Some\""^ print ~l (div :> nf) ^"\" ") ^ nl
- ^"\b (* CONVERGENT *) [" ^ nl
- ^ String.concat "\n " (List.map (fun t -> "(* _: *) " ^ (if t = `N (-1) then "PAC;" else "\""^ print ~l (t :> nf) ^"\";")) conv) ^
+ "measure="^string_of_measure(problem_measure p) (* ^ " freshno = " ^ string_of_int freshno*)
+ ^ nl ^ " Discriminating sets (deltas):"
+ ^ nl ^ " " ^ deltas ^ (if deltas = " " then "" else nl) ^ "*)"
+ ^"(* DIVERGENT *)" ^ nl
+ ^" "^ (match div with None -> "None" | Some div -> "(Some\""^ print ~l (div :> nf) ^"\")") ^ nl
+ ^" (* CONVERGENT *) [" ^ nl ^ " "
+ ^ String.concat "\n " (List.map (fun t -> "(* _ *) " ^ (if t = convergent_dummy then "" else "\""^ print ~l (t :> nf) ^"\";")) conv) ^
(if conv = [] then "" else nl)
- ^ "\b] (* NUMERIC *) [" ^ nl
+ ^ "] (* NUMERIC *) [" ^ nl ^ " "
^ String.concat "\n " (List.mapi (fun i t -> " (* "^ string_of_int i ^" *) \"" ^ print ~l (t :> nf) ^ "\";") ps)
- ^ nl
+ ^ nl ^ "] [\"*\"];;" ^ nl
;;
List.hd divs) div in
{p with div=option_map cast_to_i_var div; ps=List.map cast_to_i_n_var ps; conv=List.map cast_to_i_n_var conv}
+let cast_to_ps =
+ function
+ #i_num_var as y -> (y : i_num_var)
+ | `Bottom | `Pacman -> raise (Backtrack "BOT/PAC in ps")
+ | t ->
+ prerr_endline (print (t :> nf));
+ assert false (* algorithm failed *)
+
let subst_in_problem x inst ({freshno; div; conv; ps; sigma} as p) =
let len_ps = List.length ps in
(*(let l = Array.to_list (Array.init (freshno + 1) string_of_var) in
prerr_endline ("# INST0: " ^ string_of_var x ^ " := " ^ print ~l inst));*)
- let rec aux ((freshno,acc_ps,acc_new_ps) as acc) =
+ let rec aux_ps ((freshno,acc_ps,acc_new_ps) as acc) =
function
| [] -> acc
| t::todo_ps ->
let t = subst false false x inst (t :> nf) in
(*prerr_endline ("SUBSTITUTED t:" ^ print (t :> nf));*)
let freshno,new_t,acc_new_ps =
- expand_match (freshno,acc_ps@`Var(max_int/3,-666)::todo_ps,acc_new_ps) t
+ try
+ expand_match (freshno,acc_ps@`Var(max_int/3,-666)::todo_ps,acc_new_ps) t
+ with Pacman | Bottom -> raise (Backtrack "Pacman/Bottom in ps")
in
- aux (freshno,acc_ps@[new_t],acc_new_ps) todo_ps
+ aux_ps (freshno,acc_ps@[new_t],acc_new_ps) todo_ps
(* cut&paste from aux above *)
- and aux' ps ((freshno,acc_conv,acc_new_ps) as acc) =
+ and aux_conv ps ((freshno,acc_conv,acc_new_ps) as acc) =
function
| [] -> acc
| t::todo_conv ->
-(*prerr_endline ("EXPAND t:" ^ print (t :> nf));*)
- let t = subst false false x inst (t :> nf) in
+ (*prerr_endline ("EXPAND t:" ^ print (t :> nf));*)
+ let t = subst false false x inst (t :> nf) in
(*prerr_endline ("SUBSTITUTED t:" ^ print (t :> nf));*)
- let freshno,new_t,acc_new_ps =
+ let freshno,new_t,acc_new_ps =
+ try
expand_match (freshno,ps,acc_new_ps) t
- in
- aux' ps (freshno,acc_conv@[new_t],acc_new_ps) todo_conv
+ with Pacman -> freshno,convergent_dummy,acc_new_ps
+ | Bottom -> raise (Backtrack "Bottom in conv") in
+ aux_conv ps (freshno,acc_conv@[new_t],acc_new_ps) todo_conv
(* cut&paste from aux' above *)
- and aux'' ps (freshno,acc_new_ps) =
+ and aux_div ps (freshno,acc_new_ps) =
function
| None -> freshno, None, acc_new_ps
| Some t ->
- let t = subst false false x inst (t :> nf) in
- let freshno,new_t,acc_new_ps =
- expand_match (freshno,ps,acc_new_ps) t
- in
- freshno,Some new_t,acc_new_ps
+ try
+ let t = subst false false x inst (t :> nf) in
+ let freshno,new_t,acc_new_ps = expand_match (freshno,ps,acc_new_ps) t in
+ freshno,Some(cast_to_i_var new_t),acc_new_ps
+ with Bottom -> freshno, None, acc_new_ps
+ | Pacman -> raise (Backtrack "Pacman in div")
and expand_match ((freshno,acc_ps,acc_new_ps) as acc) t =
match t with
match u with
| `N i -> acc_new_ps,i
| _ ->
- let ps = List.map (fun t -> cast_to_i_num_var (subst false false x inst (t:> nf))) (acc_ps@acc_new_ps) in
+ let ps = List.map (fun t -> cast_to_ps (subst false false x inst (t:> nf))) (acc_ps@acc_new_ps) in
let super_simplified_ps = super_simplify_ps ps ps in
(*prerr_endline ("CERCO u:" ^ print (fst u :> nf));
List.iter (fun x -> prerr_endline ("IN: " ^ print (fst x :> nf))) ps;
(*prerr_endline ("NUOVO t:" ^ print (fst t :> nf) ^ " more_args=" ^ string_of_int (snd t));*)
expand_match (freshno,acc_ps,acc_new_ps) t
| `Lam _ -> assert false (* algorithm invariant/loose typing *)
- | `Bottom | `Pacman -> raise (Backtrack "BOT or PAC in toplevel numeric positioon")
+ | `Bottom -> raise Bottom
+ | `Pacman -> raise Pacman
| #i_n_var as x ->
let x = simple_expand_match (acc_ps@acc_new_ps) x in
freshno,cast_to_i_num_var x,acc_new_ps in
- let freshno,old_ps,new_ps = aux (freshno,[],[]) (ps :> i_num_var list) in
- let freshno,conv,new_ps = aux' old_ps (freshno,[],new_ps) (conv :> i_num_var list) in
- let freshno,div,new_ps = aux'' old_ps (freshno,new_ps) (div :> i_num_var option) in
- let div = option_map cast_to_i_var div in
+ let freshno,old_ps,new_ps = aux_ps (freshno,[],[]) (ps :> i_num_var list) in
+ let freshno,conv,new_ps = aux_conv old_ps (freshno,[],new_ps) (conv :> i_num_var list) in
+ let freshno,div,new_ps = aux_div old_ps (freshno,new_ps) (div :> i_num_var option) in
+
let ps = List.map cast_to_i_n_var (old_ps @ new_ps) in
let conv = List.map cast_to_i_n_var conv in
(let l = Array.to_list (Array.init (freshno + 1) string_of_var) in
then p
else
let n = match div with `I(_,args) -> Listx.length args | `Var _ -> 0 in
- let p, bomb' = make_fresh_var p (-666) in
- (if !bomb <> `Var (-1,-666) then
- failwithProblem p
- ("Bomb was duplicated! It was " ^ string_of_nf !bomb ^
- ", tried to change it to " ^ string_of_nf bomb'));
- bomb := bomb';
- prerr_endline ("Just created bomb var: " ^ string_of_nf !bomb);
let x = hd_of_i_var div in
- let inst = make_lams !bomb n in
- prerr_endline ("# INST (div): " ^ string_of_var x ^ " := " ^ string_of_nf inst);
- let p = {p with div=None} in
- (* subst_in_problem (hd_of_i_var div) inst p in *)
- {p with sigma=p.sigma@[x,inst]} in
- let dangerous_conv = showstoppers_conv in
+ let inst = make_lams `Bottom n in
+ subst_in_problem x inst p in
+ let dangerous_conv = showstoppers_conv in
let _ = prerr_endline ("dangerous_conv lenght:" ^ string_of_int (List.length dangerous_conv));
List.iter (fun l -> prerr_endline (String.concat " " (List.map string_of_var l))) dangerous_conv; in
let conv =
let _ = List.find (fun h -> hd_of t = Some h) showstoppers in
t)
with Not_found -> match hd_of t with
- | None -> assert (t = `N ~-1); t
+ | None -> assert (t = convergent_dummy); t
| Some h ->
prerr_endline ("FREEZING " ^ string_of_var h);
- `N ~-1 (* convergent dummy*)
+ convergent_dummy
) (List.combine showstoppers_conv p.conv) in
List.iter
(fun bs ->
`Continue p
let instantiate p x perm n =
- (if hd_of_i_var (cast_to_i_var !bomb) = x
- then failwithProblem p ("BOMB (" ^ string_of_nf !bomb ^ ") cannot be instantiated!"));
let arity_of_x = max_arity_tms x (all_terms p) in
(if arity_of_x = None then failwithProblem p "step on var non occurring in problem");
let arity_of_x = Util.option_get(arity_of_x) in
replace_in_sigma (List.rev perm) p.sigma
;;
-let env_of_sigma freshno sigma should_explode =
+let env_of_sigma freshno sigma =
let rec aux n =
if n > freshno then
[]
(try
e,Pure.lift (-n-1) (snd (List.find (fun (i,_) -> i = n) sigma)),[]
with
- Not_found ->
- if should_explode && n = hd_of_i_var (cast_to_i_var !bomb)
- then ([], (let f t = Pure.A(t,t) in f (Pure.L (f (Pure.V 0)))), [])
- else ([],Pure.V n,[]))::e
+ Not_found -> ([],Pure.V n,[]))::e
in aux 0
;;
-prerr_endline "########## main ##########";;
-
-(* Commands:
- v ==> v := \a. a k1 .. kn \^m.0
- + ==> v := \^k. numero for every v such that ...
- * ==> tries v as long as possible and then +v as long as possible
-*)
-let main problems =
- let rec aux ({ps} as p) n l =
- if List.for_all (function `N _ -> true | _ -> false) ps && p.div = None then begin
- p
- end else
- let _ = prerr_endline (string_of_problem "main" p) in
- let x,l =
- match l with
- | cmd::l -> cmd,l
- | [] -> read_line (),[] in
- let cmd =
- if x = "+" then
- `DoneWith
- else if x = "*" then
- `Auto
- else
- `Step x in
- match cmd with
- | `DoneWith -> assert false (*aux (eat p) n l*) (* CSC: TODO *)
- | `Step x -> assert false
- (* let x = var_of_string x in
- aux (instantiate p x 1 n) n l *)
- | `Auto -> aux (auto p n) n l
- in
- List.iter
- (fun (p,n,cmds) ->
- Console.print_hline();
- bomb := `Var (-1,-666);
- let p_finale = aux p n cmds in
- let freshno,sigma = p_finale.freshno, p_finale.sigma in
- prerr_endline ("------- <DONE> ------\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 (" BOMB == " ^ print ~l !bomb);
- prerr_endline "---------------------";
- List.iter (fun (x,inst) -> prerr_endline (string_of_var x ^ " := " ^ print ~l inst)) sigma;
+let solve p =
+ 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 =
+ try
+ auto p p.initialSpecialK
+ with Backtrack _ -> raise (Fail "Unsolvable problem, apparently") 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 ;
+ 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 ;
*)
- 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
- List.iter (fun (x,inst) -> prerr_endline (string_of_var x ^ " := " ^ print ~l inst)) sigma;
- prerr_endline "---------<PURE>---------";
- let div = option_map (fun div -> ToScott.scott_of_nf (div :> nf)) p.div in
- let conv = List.map (fun t -> ToScott.scott_of_nf (t :> nf)) p.conv in
- let ps = List.map (fun t -> ToScott.scott_of_nf (t :> nf)) p.ps in
- let sigma = List.map (fun (x,inst) -> x, ToScott.scott_of_nf inst) sigma in
- (*let ps_ok = List.fold_left (fun ps (x,inst) ->
- List.map (Pure.subst false x inst) ps) ps sigma in*)
- let e = env_of_sigma freshno sigma true in
- let e' = env_of_sigma freshno sigma false in
+ 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
+ List.iter (fun (x,inst) -> prerr_endline (string_of_var x ^ " := " ^ print ~l inst)) sigma;
+
+ prerr_endline "---------<PURE>---------";
+ let scott_of_nf t = ToScott.scott_of_nf (t :> nf) in
+ let div = option_map scott_of_nf p.div in
+ let conv = List.map scott_of_nf p.conv in
+ let ps = List.map scott_of_nf p.ps in
+
+ let sigma' = List.map (fun (x,inst) -> x, ToScott.scott_of_nf inst) sigma in
+ let e' = env_of_sigma freshno sigma' in
(*
- prerr_endline "---------<PPP>---------";
+ prerr_endline "---------<PPP>---------";
let rec print_e e =
- "[" ^ String.concat ";" (List.map (fun (e,t,[]) -> print_e e ^ ":" ^ Pure.print t) 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 (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>---------";
- (function Some div ->
- print_endline (Pure.print div);
- let t = Pure.mwhd (e',div,[]) in
- prerr_endline ("*:: " ^ (Pure.print t));
- prerr_endline (print !bomb);
- assert (t = ToScott.scott_of_nf (!bomb:>nf))
- | None -> ()) div;
- List.iter (fun n ->
- prerr_endline ("_::: " ^ (Pure.print n));
- let t = Pure.mwhd (e,n,[]) in
- prerr_endline ("_:: " ^ (Pure.print t))
- ) conv ;
- List.iteri (fun i n ->
- prerr_endline ((string_of_int i) ^ "::: " ^ (Pure.print n));
- let t = Pure.mwhd (e,n,[]) in
- prerr_endline ((string_of_int i) ^ ":: " ^ (Pure.print t));
- assert (t = Scott.mk_n i)
- ) ps ;
- prerr_endline "-------- </DONE> --------"
- ) problems
+ prerr_endline "--------<REDUCE>---------";
+ (function Some div ->
+ print_endline (Pure.print div);
+ let t = Pure.mwhd (e',div,[]) in
+ prerr_endline ("*:: " ^ (Pure.print t));
+ assert (t = Pure.B)
+ | None -> ()) div;
+ List.iter (fun n ->
+ verbose ("_::: " ^ (Pure.print n));
+ let t = Pure.mwhd (e',n,[]) in
+ verbose ("_:: " ^ (Pure.print t));
+ assert (t <> Pure.B)
+ ) conv ;
+ List.iteri (fun i n ->
+ verbose ((string_of_int i) ^ "::: " ^ (Pure.print n));
+ let t = Pure.mwhd (e',n,[]) in
+ verbose ((string_of_int i) ^ ":: " ^ (Pure.print t));
+ assert (t = Scott.mk_n i)
+ ) ps ;
+ prerr_endline "-------- </DONE> --------"
+ )
+;;
(********************** problems *******************)
| _ -> assert false
;;
-type t = problem * int * string list;;
-
-let magic_conv ~div ~conv ~nums cmds =
+let problem_of ~div ~conv ~nums =
let all_tms = (match div with None -> [] | Some div -> [div]) @ nums @ conv in
let all_tms, var_names = parse' all_tms in
let div, (tms, conv) = match div with
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; trail=[]}, 0, []
+ {freshno=0; div=None; conv=[]; ps=[]; sigma=[]; deltas=[]; initialSpecialK=0; trail=[]}
) 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 = option_map cast_to_i_var div in
- let conv = Util.filter_map (function #i_n_var as t -> Some (cast_to_i_n_var t) | _ -> None) conv in
- let tms = List.map cast_to_i_n_var tms in
+ let div =
+ match div with
+ | None | Some `Bottom -> None
+ | Some (`I _ as t) -> Some t
+ | _ -> raise (Fail "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 (Fail "A term in conv is not i_n_var")
+ ) conv in
+ let tms = List.map (
+ function
+ | #i_n_var as y -> y
+ | _ -> raise (Fail "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 dummy = `Var (max_int / 2, -666) in
[ ref (Array.to_list (Array.init (List.length ps) (fun i -> i, dummy))) ] in
let trail = [] in
- {freshno; div; conv; ps; sigma=[] ; deltas; initialSpecialK=special_k; trail}, special_k, cmds
+ {freshno; div; conv; ps; sigma=[] ; deltas; initialSpecialK=special_k; trail}
;;
-let magic strings cmds = magic_conv None [] strings cmds;;
+let should_fail f =
+ try
+ solve (f ());
+ failwith "The problem should have failed"
+ with Fail _ ->
+ prerr_endline "The problem failed, as expected"
+;;