1 (* Copyright (C) 2005, HELM Team.
3 * This file is part of HELM, an Hypertextual, Electronic
4 * Library of Mathematics, developed at the Computer Science
5 * Department, University of Bologna, Italy.
7 * HELM is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version 2
10 * of the License, or (at your option) any later version.
12 * HELM is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with HELM; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place - Suite 330, Boston,
22 * For details, see the HELM World-Wide-Web page,
23 * http://helm.cs.unibo.it/
29 let debug_print s = if debug then prerr_endline (Lazy.force s) else ()
31 exception Error of string lazy_t
32 let fail msg = raise (Error msg)
34 type goal = ProofEngineTypes.goal
38 type switch = Open of goal | Closed of goal
39 type locator = int * switch
40 type tag = [ `BranchTag | `FocusTag | `NoTag ]
41 type entry = locator list * locator list * locator list * tag
44 let empty = [ [], [], [], `NoTag ]
46 let fold ~env ~cont ~todo init stack =
47 let rec aux acc depth =
50 | (locs, todos, conts, tag) :: tl ->
51 let acc = List.fold_left (fun acc -> env acc depth tag) acc locs in
52 let acc = List.fold_left (fun acc -> cont acc depth tag) acc conts in
53 let acc = List.fold_left (fun acc -> todo acc depth tag) acc todos in
54 aux acc (depth + 1) tl
59 let iter ~env ~cont ~todo =
60 fold ~env:(fun _ -> env) ~cont:(fun _ -> cont) ~todo:(fun _ -> todo) ()
62 let map ~env ~cont ~todo =
63 let depth = ref ~-1 in
65 (fun (s, t, c, tag) ->
68 env d tag s, todo d tag t, cont d tag c, tag)
70 let is_open = function _, Open _ -> true | _ -> false
71 let close = function n, Open g -> n, Closed g | l -> l
72 let filter_open = List.filter is_open
73 let is_fresh = function n, Open _ when n > 0 -> true | _ -> false
74 let goal_of_loc = function _, Open g | _, Closed g -> g
75 let goal_of_switch = function Open g | Closed g -> g
76 let switch_of_loc = snd
78 let zero_pos = List.map (fun g -> 0, Open g)
81 let pos = ref 0 in (* positions are 1-based *)
82 List.map (function _, sw -> incr pos; !pos, sw) locs
87 | [] -> fail (lazy (sprintf "relative position %d not found" i))
88 | (i', _) as loc :: tl when i = i' -> loc, (List.rev acc) @ tl
89 | hd :: tl -> aux (hd :: acc) tl
95 List.map (fun l -> if List.mem (goal_of_loc l) gs then close l else l)
97 let rm _ _ = List.filter (fun l -> not (List.mem (goal_of_loc l) gs)) in
98 map ~env:close ~cont:rm ~todo:rm
102 | [] -> raise (Failure "Continuationals.find_goal")
103 | (l :: _, _ , _ , _) :: _ -> goal_of_loc l
104 | ( _ , _ , l :: _, _) :: _ -> goal_of_loc l
105 | ( _ , l :: _, _ , _) :: _ -> goal_of_loc l
106 | _ :: tl -> find_goal tl
111 | [ [], [], [], `NoTag ] -> true
114 let of_metasenv metasenv =
115 let goals = List.map (fun (g, _, _) -> g) metasenv in
116 [ zero_pos goals, [], [], `NoTag ]
120 | (locs, _, _, _) :: _ -> List.map switch_of_loc locs
125 | (locs, _, _, _) :: _ -> List.map goal_of_loc locs
130 | (_, _, _, tag) :: _ -> tag
135 | _ :: (locs, _, _, _) :: _ -> List.map goal_of_loc locs
139 let open_goals stack =
140 let add_open acc _ _ l = if is_open l then goal_of_loc l :: acc else acc in
141 List.rev (fold ~env:add_open ~cont:add_open ~todo:add_open [] stack)
143 let (@+) = (@) (* union *)
145 let (@-) s1 s2 = (* difference *)
147 (fun e acc -> if List.mem e s2 then acc else e :: acc)
150 let (@~-) locs gs = (* remove some goals from a locators list *)
152 (fun loc acc -> if List.mem (goal_of_loc loc) gs then acc else loc :: acc)
156 let pp_goal = string_of_int in
158 function Open g -> "o" ^ pp_goal g | Closed g -> "c" ^ pp_goal g
160 let pp_loc (i, s) = string_of_int i ^ pp_switch s in
161 let pp_env env = sprintf "[%s]" (String.concat ";" (List.map pp_loc env)) in
162 let pp_tag = function `BranchTag -> "B" | `FocusTag -> "F" | `NoTag -> "N" in
163 let pp_stack_entry (env, todo, cont, tag) =
164 sprintf "(%s, %s, %s, %s)" (pp_env env) (pp_env todo) (pp_env cont)
167 String.concat " :: " (List.map pp_stack_entry stack)
177 val id_tactic : tactic
178 val mk_tactic : (input_status -> output_status) -> tactic
179 val apply_tactic : tactic -> input_status -> output_status
181 val goals : output_status -> goal list * goal list (** opened, closed goals *)
182 val set_goals: goal list * goal list -> output_status -> output_status
183 val get_stack : input_status -> Stack.t
184 val set_stack : Stack.t -> output_status -> output_status
186 val inject : input_status -> output_status
187 val focus : goal -> output_status -> input_status
212 | Tactical of tactical
214 val eval: t -> input_status -> output_status
217 module Make (S: Status) =
221 type input_status = S.input_status
222 type output_status = S.output_status
223 type tactic = S.tactic
238 | Tactical of tactical
243 | Semicolon -> "Semicolon"
246 | Pos i -> "Pos " ^ string_of_int i
249 sprintf "Focus [%s]" (String.concat "; " (List.map string_of_int gs))
250 | Unfocus -> "Unfocus"
251 | Tactical _ -> "Tactical <abs>"
253 let eval_tactical tactical ostatus switch =
254 match tactical, switch with
255 | Tactic tac, Open n ->
256 let ostatus = S.apply_tactic tac (S.focus n ostatus) in
257 let opened, closed = S.goals ostatus in
258 ostatus, opened, closed
259 | Skip, Closed n -> ostatus, [], [n]
260 | Tactic _, Closed _ -> fail (lazy "can't apply tactic to a closed goal")
261 | Skip, Open _ -> fail (lazy "can't skip an open goal")
263 let eval cmd istatus =
264 let stack = S.get_stack istatus in
265 debug_print (lazy (sprintf "EVAL CONT %s <- %s" (pp_t cmd) (pp stack)));
266 let new_stack stack = S.inject istatus, stack in
268 match cmd, stack with
269 | _, [] -> assert false
270 | Tactical tac, (g, t, k, tag) :: s ->
271 if g = [] then fail (lazy "can't apply a tactic to zero goals");
272 debug_print (lazy ("context length " ^string_of_int (List.length g)));
273 let rec aux s go gc =
277 debug_print (lazy "inner eval tactical");
279 if List.exists ((=) (goal_of_loc loc)) gc then
282 let s, go', gc' = eval_tactical tac s (switch_of_loc loc) in
283 s, (go @- gc') @+ go', gc @+ gc'
287 let s0, go0, gc0 = S.inject istatus, [], [] in
288 let sn, gon, gcn = aux s0 go0 gc0 g in
289 debug_print (lazy ("opened: "
290 ^ String.concat " " (List.map string_of_int gon)));
291 debug_print (lazy ("closed: "
292 ^ String.concat " " (List.map string_of_int gcn)));
294 (zero_pos gon, t @~- gcn, k @~- gon, tag) :: deep_close gcn s
297 | Dot, ([], _, [], _) :: _ ->
298 (* backward compatibility: do-nothing-dot *)
300 | Dot, (g, t, k, tag) :: s ->
301 (match filter_open g, k with
302 | loc :: loc_tl, _ -> new_stack (([ loc ], t, loc_tl @+ k, tag) :: s)
304 assert (is_open loc);
305 new_stack (([ loc ], t, k, tag) :: s)
306 | _ -> fail (lazy "can't use \".\" here"))
307 | Semicolon, _ -> new_stack stack
308 | Branch, (g, t, k, tag) :: s ->
309 (match init_pos g with
310 | [] | [ _ ] -> fail (lazy "too few goals to branch");
313 (([ loc ], [], [], `BranchTag) :: (loc_tl, t, k, tag) :: s))
314 | Shift, (g, t, k, `BranchTag) :: (g', t', k', tag) :: s ->
316 | [] -> fail (lazy "no more goals to shift")
319 (([ loc ], t @+ filter_open g, [],`BranchTag)
320 :: (loc_tl, t', k', tag) :: s))
321 | Shift, _ -> fail (lazy "can't shift goals here")
322 | Pos i, ([ loc ], [], [],`BranchTag) :: (g', t', k', tag) :: s
324 let loc_i, g' = extract_pos i g' in
326 (([ loc_i ], [], [],`BranchTag)
327 :: ([ loc ] @+ g', t', k', tag) :: s)
328 | Pos i, (g, t, k,`BranchTag) :: (g', t', k', tag) :: s ->
329 let loc_i, g' = extract_pos i g' in
331 (([ loc_i ], [], [],`BranchTag)
332 :: (g', t' @+ filter_open g, k', tag) :: s)
333 | Pos _, _ -> fail (lazy "can't use relative positioning here")
334 | Merge, (g, t, k,`BranchTag) :: (g', t', k', tag) :: s ->
335 new_stack ((t @+ filter_open g @+ g' @+ k, t', k', tag) :: s)
336 | Merge, _ -> fail (lazy "can't merge goals here")
337 | Focus [], _ -> assert false
340 let add_l acc _ _ l = if is_open l then l :: acc else acc in
341 Stack.fold ~env:add_l ~cont:add_l ~todo:add_l [] s
345 if not (List.exists (fun l -> goal_of_loc l = g) stack_locs) then
346 fail (lazy (sprintf "goal %d not found (or closed)" g)))
348 new_stack ((zero_pos gs, [], [], `FocusTag) :: deep_close gs s)
349 | Unfocus, ([], [], [], `FocusTag) :: s -> new_stack s
350 | Unfocus, _ -> fail (lazy "can't unfocus, some goals are still open")
352 debug_print (lazy (sprintf "EVAL CONT %s -> %s" (pp_t cmd) (pp stack)));
353 S.set_stack stack ostatus