1 (***********************************************************************)
5 (* Kim Nguyen, LRI UMR8623 *)
6 (* Université Paris-Sud & CNRS *)
8 (* Copyright 2010-2013 Université Paris-Sud and Centre National de la *)
9 (* Recherche Scientifique. All rights reserved. This file is *)
10 (* distributed under the terms of the GNU Lesser General Public *)
11 (* License, with the special exception on linking described in file *)
14 (***********************************************************************)
17 Time-stamp: <Last modified on 2013-03-04 18:18:37 CET by Kim Nguyen>
24 type move = [ `Left | `Right | `Up1 | `Up2 | `Epsilon ]
25 type state_ctx = { mutable left : StateSet.t;
26 mutable right : StateSet.t;
27 mutable up1 : StateSet.t;
28 mutable up2 : StateSet.t;
29 mutable epsilon : StateSet.t}
31 type pred_ = move * bool * State.t
33 module Move : (Formula.PREDICATE with type data = pred_ and type ctx = state_ctx ) =
38 type t = move * bool * State.t
39 let equal n1 n2 = n1 = n2
40 let hash n = Hashtbl.hash n
45 let make_ctx a b c d e =
46 { left = a; right = b; up1 = c; up2 = d; epsilon = e }
48 include Hcons.Make(Node)
49 let _pr_buff = Buffer.create 10
50 let _str_fmt = formatter_of_buffer _pr_buff
51 let _flush_str_fmt () = pp_print_flush _str_fmt ();
52 let s = Buffer.contents _pr_buff in
53 Buffer.clear _pr_buff; s
56 let _ = _flush_str_fmt () in
58 let m, b, s = a.node in
61 | `Left -> Pretty.down_arrow, Pretty.subscript 1
62 | `Right -> Pretty.down_arrow, Pretty.subscript 2
63 | `Epsilon -> Pretty.epsilon, ""
64 | `Up1 -> Pretty.up_arrow, Pretty.subscript 1
65 | `Up2 -> Pretty.up_arrow, Pretty.subscript 2
67 fprintf _str_fmt "%s%s" dir num;
68 State.print _str_fmt s;
69 let str = _flush_str_fmt () in
70 if b then fprintf ppf "%s" str
71 else Pretty.pp_overline ppf str
74 let l, b, s = p.node in
76 exception NegativeAtom of (move*State.t)
78 let l, b, s = p.node in
79 if b then raise (NegativeAtom(l,s));
86 | `Epsilon -> ctx.epsilon
90 module SFormula = Formula.Make(Move)
93 mutable states : StateSet.t;
94 (* mutable top_states : StateSet.t;
95 mutable bottom_states: StateSet.t; *)
96 mutable selection_states: StateSet.t;
97 transitions: (State.t, (QNameSet.t*SFormula.t) list) Hashtbl.t;
100 let next = Uid.make_maker ()
102 let create () = { id = next ();
103 states = StateSet.empty;
104 (* top_states = StateSet.empty;
105 bottom_states = StateSet.empty; *)
106 selection_states = StateSet.empty;
107 transitions = Hashtbl.create 17;
112 [add_trans a q labels f] adds a transition [(q,labels) -> f] to the
113 automaton [a] but ensures that transitions remains pairwise disjoint
116 let add_trans a q s f =
117 let trs = try Hashtbl.find a.transitions q with Not_found -> [] in
119 List.fold_left (fun (acup, atrs) (labs, phi) ->
120 let lab1 = QNameSet.inter labs s in
121 let lab2 = QNameSet.diff labs s in
123 if QNameSet.is_empty lab1 then []
124 else [ (lab1, SFormula.or_ phi f) ]
127 if QNameSet.is_empty lab2 then []
128 else [ (lab2, SFormula.or_ phi f) ]
130 (QNameSet.union acup labs, tr1@ tr2 @ atrs)
131 ) (QNameSet.empty, []) trs
133 let rem = QNameSet.diff s cup in
134 let ntrs = if QNameSet.is_empty rem then ntrs
135 else (rem, f) :: ntrs
137 Hashtbl.replace a.transitions q ntrs
139 let _pr_buff = Buffer.create 50
140 let _str_fmt = formatter_of_buffer _pr_buff
141 let _flush_str_fmt () = pp_print_flush _str_fmt ();
142 let s = Buffer.contents _pr_buff in
143 Buffer.clear _pr_buff; s
147 "\nInternal UID: %i@\n\
149 Selection states: %a@\n\
150 Alternating transitions:@\n"
152 StateSet.print a.states
153 StateSet.print a.selection_states;
156 (fun q t acc -> List.fold_left (fun acc (s , f) -> (q,s,f)::acc) acc t)
160 let sorted_trs = List.stable_sort (fun (q1, s1, phi1) (q2, s2, phi2) ->
161 let c = State.compare q1 q2 in - (if c == 0 then QNameSet.compare s1 s2 else c))
164 let _ = _flush_str_fmt () in
165 let strs_strings, max_pre, max_all = List.fold_left (fun (accl, accp, acca) (q, s, f) ->
166 let s1 = State.print _str_fmt q; _flush_str_fmt () in
167 let s2 = QNameSet.print _str_fmt s; _flush_str_fmt () in
168 let s3 = SFormula.print _str_fmt f; _flush_str_fmt () in
169 let pre = Pretty.length s1 + Pretty.length s2 in
170 let all = Pretty.length s3 in
171 ( (q, s1, s2, s3) :: accl, max accp pre, max acca all)
172 ) ([], 0, 0) sorted_trs
174 let line = Pretty.line (max_all + max_pre + 6) in
175 let prev_q = ref State.dummy in
176 List.iter (fun (q, s1, s2, s3) ->
177 if !prev_q != q && !prev_q != State.dummy then fprintf fmt " %s\n%!" line;
179 fprintf fmt " %s, %s" s1 s2;
180 fprintf fmt "%s" (Pretty.padding (max_pre - Pretty.length s1 - Pretty.length s2));
181 fprintf fmt " %s %s@\n%!" Pretty.right_arrow s3;
183 fprintf fmt " %s\n%!" line
186 [complete transitions a] ensures that for each state q
187 and each symbols s in the alphabet, a transition q, s exists.
188 (adding q, s -> F when necessary).
191 let complete_transitions a =
192 StateSet.iter (fun q ->
193 let qtrans = Hashtbl.find a.transitions q in
195 List.fold_left (fun rem (labels, _) ->
196 QNameSet.diff rem labels) QNameSet.any qtrans
199 if QNameSet.is_empty rem then qtrans
201 (rem, SFormula.false_) :: qtrans
203 Hashtbl.replace a.transitions q nqtrans
206 (* [normalize_negations a] removes negative atoms in the formula
207 complementing the sub-automaton in the negative states.
208 [TODO check the meaning of negative upward arrows]
210 let normalize_negations a =
211 let memo_state = Hashtbl.create 17 in
212 let todo = Queue.create () in
214 match SFormula.expr f with
215 Formula.True | Formula.False -> if b then f else SFormula.not_ f
216 | Formula.Or(f1, f2) -> (if b then SFormula.or_ else SFormula.and_)(flip b f1) (flip b f2)
217 | Formula.And(f1, f2) -> (if b then SFormula.and_ else SFormula.or_)(flip b f1) (flip b f2)
218 | Formula.Atom(a) -> begin
219 let l, b', q = Move.node a in
220 if b == b' then begin
221 (* a appears positively, either no negation or double negation *)
222 if not (Hashtbl.mem memo_state (q,b)) then Queue.add (q,true) todo;
223 SFormula.atom_ (Move.make (l, true, q))
225 (* need to reverse the atom
226 either we have a positive state deep below a negation
227 or we have a negative state in a positive formula
228 b' = sign of the state
229 b = sign of the containing formula
233 (* does the inverted state of q exist ? *)
234 Hashtbl.find memo_state (q, false)
237 (* create a new state and add it to the todo queue *)
238 let nq = State.make () in
239 Hashtbl.add memo_state (q, false) nq;
240 Queue.add (q, false) todo; nq
242 SFormula.atom_ (Move.make (l, true, not_q))
246 StateSet.iter (fun q -> Queue.add (q, true) todo) a.selection_states;
247 while not (Queue.is_empty todo) do
248 let (q, b) as key = Queue.pop todo in
251 Hashtbl.find memo_state key
254 let nq = if b then q else State.make () in
255 Hashtbl.add memo_state key nq; nq
257 let trans = Hashtbl.find a.transitions q in
258 let trans' = List.map (fun (lab, f) -> lab, flip b f) trans in
259 Hashtbl.replace a.transitions q' trans'