X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=ocaml%2Flambda4.ml;h=7b669ca3789880e524c6d6870d1111a64999cfba;hb=a34071ed728b8de44b198de4e73a52207557ed81;hp=e9aa59dce7094eac40af0f8373cdd7410ecfe570;hpb=b2e89f8c6a89ad675718acdf35cdd0abfafaad5a;p=fireball-separation.git

diff --git a/ocaml/lambda4.ml b/ocaml/lambda4.ml
index e9aa59d..7b669ca 100644
--- a/ocaml/lambda4.ml
+++ b/ocaml/lambda4.ml
@@ -27,15 +27,18 @@ type problem =
  ; sigma: (int * nf) list (* the computed substitution *)
  ; deltas: discriminating_set ref list (* collection of all branches *)
  ; initialSpecialK: int
+ ; label : string
+ ; var_names : string list (* names of the original free variables *)
 
  ; trail: discriminating_set list list
 };;
 
+let label_of_problem {label} = label;;
+
 (* 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
@@ -76,7 +79,7 @@ let string_of_measure = string_of_int;;
 
 let string_of_problem label ({freshno; div; conv; ps; deltas} as p) =
  Console.print_hline ();
- prerr_string ("\n(* DISPLAY PROBLEM (" ^ label ^ ") - ");
+ prerr_string ("\n(* DISPLAY PROBLEM (" ^ p.label ^ " - " ^ 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
@@ -113,7 +116,7 @@ let make_fresh_vars p arities =
 
 let simple_expand_match ps =
  let rec aux_nob level = function
-  | #i_num_var as t -> aux_i_num_var level t
+  | #i_num_var as t -> (aux_i_num_var level t :> nf)
   | `Lam(b,t) -> `Lam(b,aux (level+1) t)
   | `Pacman as t -> t
  and aux level = function
@@ -121,20 +124,20 @@ let simple_expand_match ps =
   | #nf_nob as t -> aux_nob level t
  and aux_i_num_var level = function
   | `Match(u,v,bs_lift,bs,args) as torig ->
-    let u = aux_i_num_var level u in
+    let (u : i_num_var) = aux_i_num_var level u in
     bs := List.map (fun (n, x) -> n, aux 0 x) !bs;
     (try
        (match u with
          | #i_n_var as u ->
-            let i = index_of (lift (-level) u) (ps :> nf list) (* can raise Not_found *)
-            in let t = mk_match (`N i) v bs_lift bs (args :> nf list) in
+            let i = index_of ~eq:eta_eq (lift (-level) u) (ps :> nf list) in (* can raise Not_found *)
+            let t = cast_to_i_num_var (mk_match (`N i) v bs_lift bs (args :> nf list)) in
             if t <> torig then
-            aux level (t :> nf)
-           else raise Not_found
+             aux_i_num_var level t
+            else raise Not_found
          | _ -> raise Not_found)
       with Not_found ->
-       mk_appl (`Match(cast_to_i_num_var u,v,bs_lift,bs,[])) (List.map (aux_nob level) args))
-  | `I(v,args) -> mk_appl (`Var v) (List.map (aux_nob level) (Listx.to_list args))
+       cast_to_i_num_var (mk_appl (`Match(u,v,bs_lift,bs,[])) (List.map (aux_nob level) args)))
+  | `I(v,args) -> cast_to_i_num_var (mk_appl (`Var v) (List.map (aux_nob level) (Listx.to_list args)))
   | `N _ | `Var _ as t -> t
  in aux_i_num_var 0
 ;;
@@ -144,18 +147,22 @@ let fixpoint f =
 ;;
 
 let rec super_simplify_ps ps =
+ fixpoint (List.map (fun x -> cast_to_i_n_var (simple_expand_match ps (x :> i_num_var))))
+;;
+
+let rec super_simplify_ps_with_match ps =
  fixpoint (List.map (cast_to_i_num_var ++ (simple_expand_match ps)))
 ;;
 
 let super_simplify ({div; ps; conv} as p) =
-  let ps = super_simplify_ps p.ps (p.ps :> i_num_var list) in
-  let conv = super_simplify_ps ps (p.conv :> i_num_var list) in
+  let ps = super_simplify_ps p.ps p.ps in
+  let conv = super_simplify_ps ps p.conv in
   let div = option_map (fun div ->
-   let divs = super_simplify_ps p.ps ([div] :> i_num_var list) in
+   let divs = super_simplify_ps p.ps ([div] :> i_n_var list) in
     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}
+  {p with div=option_map cast_to_i_var div; ps; conv}
 
-let cast_to_ps =
+let cast_to_ps_with_match =
  function
     #i_num_var as y -> (y : i_num_var)
   | `Bottom | `Pacman -> raise (Backtrack "BOT/PAC in ps")
@@ -201,12 +208,17 @@ prerr_endline ("# INST0: " ^ string_of_var x ^ " := " ^ print ~l inst));*)
    function
    | None -> freshno, None, acc_new_ps
    | Some t ->
+      let t = subst false false x inst (t :> nf) in
       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")
+        (* backtrack if it is a number or a variable *)
+        match new_t with
+         | `N _   -> raise (Backtrack "div=`N")
+         | `Var _
+         | `I _ as new_t -> freshno, Some(new_t), acc_new_ps
+      with
+       | Bottom -> freshno, None, acc_new_ps
+       | Pacman -> raise (Backtrack "div=PAC")
 
   and expand_match ((freshno,acc_ps,acc_new_ps) as acc) t =
    match t with
@@ -216,12 +228,12 @@ prerr_endline ("# INST0: " ^ string_of_var x ^ " := " ^ print ~l inst));*)
          match u with
          | `N i -> acc_new_ps,i
          | _ ->
-            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
+            let ps = List.map (fun t -> cast_to_ps_with_match (subst false false x inst (t:> nf))) (acc_ps@acc_new_ps) in
+            let super_simplified_ps = super_simplify_ps_with_match ps ps in
 (*prerr_endline ("CERCO u:" ^ print (fst u :> nf));
 List.iter (fun x -> prerr_endline ("IN: " ^ print (fst x :> nf))) ps;
 List.iter (fun x -> prerr_endline ("IN2: " ^ print (fst x :> nf))) super_simplified_ps;*)
-            match index_of_opt ~eq:eta_eq super_simplified_ps u with
+            match index_of_opt ~eq:eta_eq super_simplified_ps (u :> i_num_var) with
                Some i -> acc_new_ps, i
              | None -> acc_new_ps@[u], len_ps + List.length acc_new_ps
         in
@@ -241,10 +253,10 @@ List.iter (fun x -> prerr_endline ("IN2: " ^ print (fst x :> nf))) super_simplif
    | `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
+      freshno,cast_to_i_n_var x,acc_new_ps 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,old_ps,new_ps = aux_ps (freshno,[],[]) ps in
+ let freshno,conv,new_ps = aux_conv old_ps (freshno,[],new_ps) conv 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
@@ -266,7 +278,7 @@ 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
 ;;
 
@@ -480,14 +492,19 @@ List.iter (fun l -> prerr_endline (String.concat " " (List.map string_of_var l))
  else
   `Continue p
 
+
+let safe_arity_of_var p x =
+ (* Compute the minimum number of arguments when x is in head
+    position at p.div or p.ps *)
+ let aux = function
+ | `Var(y,_) -> if x = y then 0 else max_int
+ | `I((y,_),args) -> if x = y then Listx.length args else max_int
+ | _ -> max_int in
+ let tms = ((match p.div with None -> [] | Some t -> [(t :> i_n_var)]) @ p.ps) in
+ List.fold_left (fun acc t -> Pervasives.min acc (aux t)) max_int tms
+;;
+
 let instantiate p x perm n =
- 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
- (if arity_of_x = min_int then failwithProblem p "step on fake variable");
- (if arity_of_x <= 0 then failwithProblem p "step on var of non-positive arity");
- (if perm < 1 || perm > arity_of_x then
-  failwithProblem p ("Tried to permutate variable "^ string_of_var x ^" beyond its max arity"));
  let n = (prerr_endline "WARNING: using constant initialSpecialK"); p.initialSpecialK in
  let arities = Array.to_list (Array.make (n+1) min_int) in
  let p,vars = make_fresh_vars p arities in
@@ -557,7 +574,10 @@ let choose_step (n,p) =
        prerr_endline ("INSTANTIATING AND HOPING " ^ string_of_var x);
        x
   with
-   Not_found -> x in
+   Not_found ->
+    let arity_of_x = max_arity_tms x (all_terms p) in
+    assert (Util.option_get arity_of_x > 0);
+    x in
 (* Instantiate in decreasing order of compute_special_k
 1:15m14s 2:13m14s 3:4m55s 4:4m43s 5:4m34s 6:6m28s 7:3m31s
 let x =
@@ -575,7 +595,8 @@ in*)
  if special_k < n then
   prerr_endline ("@@@@ NEW INSTANTIATE PHASE (" ^ string_of_int special_k ^ ") @@@@");
  let arity_of_x = Util.option_get (max_arity_tms x (all_terms p)) in
- x,arity_of_x,special_k
+ let safe_arity_of_x = safe_arity_of_var p x in
+ x, min arity_of_x safe_arity_of_x, special_k
 
 let rec auto_eat (n,p) =
  prerr_endline "{{{{{{{{ Computing measure before auto_instantiate }}}}}}";
@@ -682,139 +703,116 @@ let env_of_sigma freshno sigma =
     Not_found -> ([],Pure.V n,[]))::e
  in aux 0
 ;;
+(* ************************************************************************** *)
+
+type response = [
+ | `CompleteSeparable of string
+ | `CompleteUnseparable of string
+ | `Uncomplete
+]
+
+type result = [
+ `Complete | `Uncomplete
+] * [
+ | `Separable of (int * Num.nf) list
+ | `Unseparable of string
+]
+
+let run p =
+ 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 ");
+ 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;
 
-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 "---------<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>---------";
-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>---------";
-  (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> --------"
- )
+ 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 "--------<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> --------";
+ 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
+let solve (p, todo) =
+ let completeness, to_run =
+  match todo with
+   | `CompleteUnseparable s -> `Complete, `False s
+   | `CompleteSeparable _ -> `Complete, `True
+   | `Uncomplete -> `Uncomplete, `True in
+  match to_run with
+   | `False s -> completeness, `Unseparable s
+   | `True ->
+       try
+        let sigma = run p in
+        completeness, `Separable sigma
+       with
+       | Backtrack _ -> completeness, `Unseparable "backtrack"
 ;;
 
-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
-    | 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; 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 =
-   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 deltas =
-   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}
+let check p =
+ (* TODO check if there are duplicates in p.ps
+     before it was: ps = sort_uniq ~compare:eta_compare (ps :> nf list) *)
+ (* 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 `CompleteUnseparable "ps contains duplicates"
+ (* check if div occurs somewhere in ps@conv *)
+ else if (match p.div with
+  | None -> true
+  | Some div -> not (List.exists (eta_subterm div) (p.ps@p.conv))
+  ) && false (* TODO no bombs && pacmans *)
+  then `CompleteSeparable "no bombs, pacmans and div"
+ else if false (* TODO bombs or div fuori da lambda in ps@conv *)
+  then `CompleteUnseparable "bombs or div fuori da lambda in ps@conv"
+ else if p.div = None
+  then `CompleteSeparable "no div"
+ else `Uncomplete
 ;;
 
-let should_fail f =
- try
-  solve (f ());
-  failwith "The problem should have failed"
- with Fail _ ->
-  prerr_endline "The problem failed, as expected"
+let problem_of (label, div, conv, ps, var_names) =
+ (* TODO: replace div with bottom in problem??? *)
+ let all_tms = (match div with None -> [] | Some div -> [(div :> i_n_var)]) @ ps @ conv in
+ if all_tms = [] then failwith "problem_of: empty problem";
+ let initialSpecialK = compute_special_k (Listx.from_list (all_tms :> nf list)) in
+ 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 trail = [] in
+ let sigma = [] in
+ let p = {freshno; div; conv; ps; sigma; deltas; initialSpecialK; trail; var_names; label} in
+ p, check p
 ;;