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 2013-03-09 11:09:12 CET by Kim Nguyen>
25 let ( => ) a b = (a, b)
26 let ( ++ ) a b = Ata.SFormula.or_ a b
27 let ( %% ) a b = Ata.SFormula.and_ a b
28 let ( @: ) a b = StateSet.add a b
30 module F = Ata.SFormula
33 let node_set = QNameSet.remove QName.document QNameSet.any
34 let star_set = QNameSet.diff QNameSet.any (
35 List.fold_right (QNameSet.add)
36 [ QName.document; QName.text; QName.attribute_map ]
38 let attribute = QNameSet.singleton QName.attribute_map
39 let root_set = QNameSet.singleton QName.document
41 (* [compile_axis_test axis test q phi trans states] Takes an xpath
42 [axis] and node [test], a formula [phi], a list of [trans]itions
43 and a set of [states] and returns a formula [phi'], a new set of
44 transitions, and a new set of states such that [phi'] holds iff
45 there exists a node reachable through [axis]::[test] where [phi]
49 let compile_axis_test axis test phi trans states =
50 let q = State.make () in
51 let phi', trans', states' =
55 (q, [ test => phi ]) :: trans,
61 QNameSet.any => F.next_sibling q ]) :: trans,
65 ((if self then F.stay q else F.first_child q),
67 QNameSet.any => F.first_child q ++ F.next_sibling q;
72 let q' = State.make () in
73 let move = F.parent q ++ F.previous_sibling q' in
76 :: (q', [ QNameSet.any => move ]) :: trans,
80 let q' = State.make () in
81 let move = F.parent q ++ F.previous_sibling q' in
82 (if self then F.stay q else move),
84 QNameSet.any => move ])
85 :: (q', [ QNameSet.any => move ]) :: trans,
88 | FollowingSibling | PrecedingSibling ->
90 if axis = PrecedingSibling then
96 QNameSet.any => move ]) :: trans,
100 let test = if QNameSet.is_finite test then
101 QNameSet.fold (fun tag acc ->
102 QNameSet.add (QName.add_attribute_prefix tag) acc)
107 (q, [ test => phi %% F.is_attribute;
108 QNameSet.any => F.next_sibling q]) :: trans,
113 phi', trans', q @: states'
116 let compile_rev_axis_test axis test phi trans states =
118 | Attribute -> assert false
119 | _ -> compile_axis_test (invert_axis axis) test phi trans states
121 let rec compile_expr e trans states =
123 | Binop (e1, (And|Or as op), e2) ->
124 let phi1, trans1, states1 = compile_expr e1 trans states in
125 let phi2, trans2, states2 = compile_expr e2 trans1 states1 in
126 (if op = Or then phi1 ++ phi2 else phi1 %% phi2),
129 | Fun_call (f, [ e0 ]) when (QName.to_string f) = "not" ->
130 let phi, trans0, states0 = compile_expr e0 trans states in
131 (Ata.SFormula.not_ phi),
134 | Path p -> compile_path p trans states
137 and compile_path paths trans states =
138 List.fold_left (fun (aphi, atrans, astates) p ->
139 let phi, ntrans, nstates = compile_single_path p atrans astates in
140 (Ata.SFormula.or_ phi aphi),
142 nstates) (Ata.SFormula.false_,trans,states) paths
144 and compile_single_path p trans states =
148 (Ancestor false, QNameSet.singleton QName.document, [])::steps
149 | Relative steps -> steps
151 compile_step_list steps trans states
153 and compile_step_list l trans states =
155 | [] -> Ata.SFormula.true_, trans, states
156 | (axis, test, elist) :: ll ->
157 let phi0, trans0, states0 = compile_step_list ll trans states in
158 let phi1, trans1, states1 =
159 compile_axis_test axis test phi0 trans0 states0
161 List.fold_left (fun (aphi, atrans, astates) e ->
162 let ephi, etrans, estates = compile_expr e atrans astates in
163 aphi %% ephi, etrans, estates) (phi1, trans1, states1) elist
165 let compile_top_level_step_list l trans states =
166 let rec loop l trans states phi_above =
168 | (axis, test, elist) :: [] ->
169 let phi0, trans0, states0 =
170 compile_rev_axis_test axis QNameSet.any phi_above trans states
172 let phi1, trans1, states1 =
173 List.fold_left (fun (aphi, atrans, astates) e ->
174 let ephi, etrans, estates = compile_expr e atrans astates in
175 aphi %% ephi, etrans, estates) (phi0, trans0, states0) elist
177 let _, trans2, states2 =
178 compile_axis_test Self test phi1 trans1 states1
181 StateSet.choose (StateSet.diff states2 states1)
183 marking_state, trans2, states2
184 | (axis, test, elist) :: ll ->
185 let phi0, trans0, states0 =
186 compile_rev_axis_test axis QNameSet.any phi_above trans states
188 let phi1, trans1, states1 =
189 compile_axis_test Self test phi0 trans0 states0
191 let phi2, trans2, states2 =
192 List.fold_left (fun (aphi, atrans, astates) e ->
193 let ephi, etrans, estates = compile_expr e atrans astates in
194 aphi %% ephi, etrans, estates) (phi1, trans1, states1) elist
196 loop ll trans2 states2 phi2
199 let phi0, trans0, states0 =
202 (QNameSet.singleton QName.document)
207 loop l trans0 states0 phi0
212 let mstates, trans, states = List.fold_left (fun (ams, atrs, asts) p ->
213 let ms, natrs, nasts =
215 | Absolute l | Relative l -> compile_top_level_step_list l atrs asts
217 (StateSet.add ms ams), natrs, nasts) (StateSet.empty, [], StateSet.empty) p
219 let a = Ata.create () in
220 a.Ata.states <- states;
221 a.Ata.selection_states <- mstates;
222 List.iter (fun (q, l) ->
223 List.iter (fun (lab, phi) ->
224 Ata.add_trans a q lab phi
226 Ata.complete_transitions a;
227 Ata.normalize_negations a;