1 % (c) 2009-2025 Lehrstuhl fuer Softwaretechnik und Programmiersprachen,
2 % Heinrich Heine Universitaet Duesseldorf
3 % This software is licenced under EPL 1.0 (http://www.eclipse.org/org/documents/epl-v10.html)
4
5 :- module(bsyntaxtree,
6 [is_texpr/1, % checks if the given argument is a typed expression
7
8 get_texpr_expr/2, % get the expression part of a typed expression
9 get_texpr_type/2, % get the type of a typed expression
10 get_texpr_info/2, % get the list of information of a typed expression
11 get_texpr_id/2, % get the id of a typed identifier, fails if it's not an identifier
12 def_get_texpr_id/2, % same as above, but raises error if arg1 is not an identifier
13 def_get_texpr_ids/2, % maplist of the above, i.e., translate a typed id list into a plain list of id names
14 create_typed_id/3, % create a typed identifier
15 create_typed_ids/3, % create a list of typed identifiers from list of names and types
16 same_id/3, % true if two typed identifiers have the same id
17 same_ids/2, % true if two lists of typed identifiers have the same ids
18 same_ids_and_types/2, % also check types
19 split_names_and_types/3, % split list of typed ids into ids and types
20 get_texpr_exprs/2, % list variant of the above
21 get_texpr_types/2, % list variant of the above
22 get_texpr_infos/2, % list variant of the above
23 get_texpr_ids/2, % list variant of the above
24 get_texpr_pos/2, % get the position of a typed expression
25 get_texpr_pos_infos/2, % the a list containing the position infos, sublist of get_texpr_infos
26 extract_pos_infos/2, % get the position info sub list of an info list
27 copy_pos_infos/3, % copy position infos from one typed expression to another
28 delete_pos_info/2, % delete position info from an info list
29 propagate_pos_info_if_useful/3, % propagate position info from second list if useful
30 merge_info/3, % merge two information lists as well as possible
31 update_infos/3, % provide updates to an existing info list
32 get_info_pos/2, % get the position directly from info field
33 contains_info_pos/1, % true if info field contains position infos
34
35 same_texpr/2, % check if two typed expressions are equal modulo Info fields
36 different_texpr_values/2, % check if two type expressions are WD and definitely denote different values
37
38 create_texpr/4, % creates a typed expression by giving expression, type and infos
39 add_texpr_infos/3, % adds some more information to a typed expression at front
40 add_texpr_info_if_new/3, % adds one info field to typed B expression info list at front if it is new
41 add_texpr_infos_if_new/3, % ditto but list of infos can be added
42 add_info_if_new/3, % adds to info list
43 add_infos_if_new/3, % same for list of info items
44 safe_create_texpr/3, % a version of create_texpr which extracts wd-info from sub-expressionssafe_create_texpr
45 safe_create_texpr/4,
46 texpr_contains_wd_condition/1,
47 sub_expression_contains_wd_condition/1, % utility to check if sub-expression contains wd condition
48
49 get_rodin_name/2, get_rodin_model_name/2,
50 is_rodin_label_info/1,
51 get_texpr_label/2, get_texpr_labels/2,
52 get_info_labels/2, select_info_labels/3,
53 add_labels_to_texpr/3,
54 get_texpr_description/2, % get @desc pragma for typed expression
55 add_texpr_description/3, % add an additional description by hand
56 info_has_ignore_pragma/1, % check if an info list has an ignore pragma
57 predicate_has_ignore_pragma/1, % ditto for the info list of a predicate
58 always_well_defined/1, always_well_defined_or_disprover_mode/1,
59 always_well_defined_or_wd_reorderings_allowed/1,
60 always_well_defined_or_wd_improvements_allowed/1,
61 finite_wd_set_value/1, finite_set_or_disprover_mode/1,
62 is_truth/1, is_falsity/1,
63 conjunct_predicates/2,
64 conjunct_predicates_with_pos_info/3, conjunct_predicates_with_pos_info/2,
65 is_a_conjunct/3, is_a_conjunct_without_label/3, decompose_conjunct/3,
66 is_a_disjunct/3, is_an_implication/3, is_an_equivalence/3, is_a_negation/2,
67 conjunction_to_list/2,
68 conjunction_to_list_with_rodin_labels/2, % a variation which propagates labels down to conjuncts
69 member_in_conjunction/2, select_member_in_conjunction/3,
70 flatten_conjunctions/2,
71 size_of_conjunction/2,
72 member_in_conjunction_cse/3,
73 disjunct_predicates/2,
74 disjunct_predicates_with_pos_info/3,
75 disjunction_to_list/2,
76 is_a_disjunct_or_implication/4,
77 is_a_conjunct_or_neg_disj/3,
78
79 predicate_components/2, % split a predicate into components which use distinct identifiers
80 predicate_components_in_scope/3, % ditto with an optional list of local variables
81 predicate_components_with_restriction/4,
82 predicate_identifiers/2, predicate_identifiers_in_scope/3,
83
84 project_predicate_on_identifiers/5,
85
86 find_identifier_uses_top_level/2, % not including global sets and constants
87 find_identifier_uses/3, find_identifier_uses_if_necessary/3,
88 find_identifier_uses_l/3,
89 find_typed_identifier_uses/3,
90 find_typed_identifier_uses/2, % not including global sets and constants
91 find_typed_identifier_uses_l/3,
92 find_identifier_uses_for_quantifier_body/3,
93 get_global_identifiers/1, get_global_identifiers/2,
94 occurs_in_expr/2, some_id_occurs_in_expr/2,
95 single_usage_identifier/3,
96 update_used_ids/3,
97 check_computed_used_ids/2,
98
99 create_exists/3, create_or_merge_exists/3,
100 create_exists_or_let_predicate/3,
101 create_exists_opt_liftable/3,
102 create_exists_opt/3, create_exists_opt/4, create_exists_opt/5,
103 not_generated_exists_paras/1,
104 create_forall/3,
105 create_negation/2, is_negation_of/2, get_negated_operator_expr/2,
106 create_implication/3,
107 create_equivalence/3,
108 is_equality/3,
109 create_equality/3, split_equality/3, get_texpr_couple/3,
110 create_couple/3, create_couple/2, nested_couple_to_list/2,
111 create_cartesian_product/3,
112 create_comprehension_set/4,
113 is_eventb_comprehension_set/4, is_eventb_comprehension_set/6,
114 singleton_set_extension/2,
115 is_membership/3, is_membership_or_equality/3,
116 get_lambda_equality/4,
117 is_pow_subset/2, is_pow1_subset/2,
118
119 detect_global_predicates/4,
120
121 definitely_not_empty_set/1, definitely_empty_set/1, definitely_not_empty_finite_value/1,
122 get_integer/2,
123 get_interval/3,
124
125 replace_id_by_expr/4,
126 replace_id_by_expr_with_count/5, % also count number of replacements
127 replace_ids_by_exprs/4,
128 remove_used_id_from_info/3, % remove an id from used_id info field if it exists
129 remove_used_ids_from_info/3, % remove list of ids (order of args different !)
130
131 rename_bt/3, % a simplified version of replace_ids_by_exprs, which assumes target of renamings are variables
132 rename_bt_l/3,
133 remove_bt/4,
134 syntaxtransformation/5,
135 syntaxtransformation_det/5, % faster, non-backtracking version
136 syntaxtransformation_for_renaming/5,
137
138 map_over_bexpr/2, map_over_typed_bexpr/2, map_over_typed_bexpr/3,
139 map_over_typed_bexpr_with_names/2,
140 map_over_bexpr_top_down_acc/3, map_over_typed_bexpr_top_down_acc/3,
141 reduce_over_bexpr/4,
142 transform_bexpr/3, % transform a typed B expression bottom-up
143 transform_bexpr_with_scoping/3, % ditto, but we also provide info about local ids
144 transform_bexpr_td_with_scoping/3, % top-down with scoping
145 transform_bexpr_with_bup_accs/5, transform_bexpr_with_acc/5,
146 non_det_transform_bexpr_with_acc/5, % can be used to generate several transformed expressions
147 uses_implementable_integers/1,
148 min_max_integer_value_used/3, min_max_integer_value_used/5,
149 syntaxtraversion/6,
150 safe_syntaxelement/5,
151 safe_syntaxelement_det/5, % a deterministic, non-backtracking version
152 is_subst_syntaxelement/1,
153 is_syntax_constant/1,
154
155 expand_all_lets/2,
156
157 remove_all_infos/2, extract_info/2, extract_info/3, extract_info_wo_used_ids/2,
158 bsyntax_pattern/2,
159
160 remove_all_infos_and_ground/2,
161
162 check_if_typed_predicate/1,
163 check_if_typed_expression/1,
164 check_if_typed_substitution/1,
165
166 strip_and_norm_ast/2,
167 same_norm_texpr/2,
168 get_texpr_functor/3,
169
170 is_set_type/2, get_set_type/2, get_texpr_set_type/2,
171 is_just_type/1, is_just_type/2,
172 get_texpr_boolean/2,
173
174 create_recursive_compset/6,
175 unique_typed_id/3,
176 mark_bexpr_as_symbolic/2,
177
178 identifier_sub_ast/3, exchange_ast_position/5,
179
180 has_declared_identifier/2, add_declaration_for_identifier/3,
181 check_ast/1, check_ast/2,
182 repair_used_ids/3,
183 print_ast/1,
184 rewrite_if_then_else_expr_to_b/2,
185 normalise_bexpr_for_ml/2
186 ]).
187
188 % meta_predicate annotations should appear before loading any code:
189
190 :- meta_predicate map_over_full_bexpr_no_fail(1,?).
191
192 :- meta_predicate map_over_bexpr(1,?).
193 :- meta_predicate map_over_typed_bexpr(1,?).
194 :- meta_predicate map_over_typed_bexpr(2,?,?).
195 :- meta_predicate map_over_bexpr_top_down_acc(3,?,?).
196 :- meta_predicate map_over_typed_bexpr_top_down_acc(3,?,?).
197
198 :- meta_predicate reduce_over_bexpr(3,?,?,?).
199 :- meta_predicate transform_bexpr(2,?,?).
200 :- meta_predicate l_transform_bexpr(?,2,?).
201 :- meta_predicate transform_bexpr_with_scoping(3,?,?).
202 :- meta_predicate transform_bexpr_td_with_scoping(3,?,?).
203 :- meta_predicate transform_bexpr_with_scoping2(3,?,?,?).
204 :- meta_predicate l_transform_bexpr_with_scoping(?,3,?,?).
205 :- meta_predicate transform_bexpr_with_bup_accs(4,?,?,?,?).
206 :- meta_predicate l_transform_bexpr_with_bup_accs(?,4,?,?,?).
207 :- meta_predicate transform_bexpr_with_acc(4,?,?,?,?).
208 :- meta_predicate l_transform_bexpr_with_acc(?,4,?,?,?).
209 :- meta_predicate non_det_transform_bexpr_with_acc(4,?,?,?,?).
210 :- meta_predicate l_nd_transform_bexpr_with_acc(?,4,?,?,?).
211
212 % -----------
213
214
215 :- use_module(tools).
216
217 :- use_module(module_information,[module_info/2]).
218 :- module_info(group,typechecker).
219 :- module_info(description,'This module provides operations on the type-checked AST.').
220
221 :- use_module(library(lists)).
222 :- use_module(library(ordsets)).
223 :- use_module(library(avl)).
224 :- use_module(library(terms)).
225
226 :- use_module(self_check).
227 :- use_module(error_manager).
228 :- use_module(translate,[print_bexpr/1,translate_bexpression/2]).
229 :- use_module(gensym,[gensym/2]).
230 :- use_module(preferences,[get_preference/2,preference/2]).
231 :- use_module(debug,[debug_mode/1,debug_format/3]).
232
233 :- use_module(typing_tools,[is_finite_type_in_context/2,normalize_type/2]).
234 :- use_module(tools_lists,[convlist_max/4]).
235
236 :- set_prolog_flag(double_quotes, codes).
237
238 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
239 % basic access to enriched syntax tree
240
241 is_texpr(b(_,_,_)).
242
243 get_texpr_expr(b(Name,_,_),R) :- !,R=Name.
244 get_texpr_expr(E,_) :- add_error_fail(get_texpr_expr,'B Expression not properly wrapped: ',E).
245
246 get_texpr_type(b(_,Type,_),R) :- !, R=Type.
247 get_texpr_type(E,_) :- add_error_fail(get_texpr_type,'B Expression not properly wrapped: ',E).
248 get_texpr_info(b(_,_,Info),R) :- !, R=Info.
249 get_texpr_info(E,_) :- add_error_fail(get_texpr_info,'B Expression not properly wrapped: ',E).
250
251 %! get_texpr_id(+Texpr,-Id)
252 get_texpr_id(b(N,_,_),Id) :- !, N=identifier(Id).
253 get_texpr_id(E,_) :- add_error_fail(get_texpr_id,'B Expression not properly wrapped: ',E).
254 /* same as above: but must succeed */
255 def_get_texpr_id(b(identifier(Id),_,_),R) :- !,R=Id.
256 def_get_texpr_id(b(E,_,_),_) :- !,
257 add_error_fail(def_get_texpr_id,'Could not extract identifier from typed expression: ',E).
258 def_get_texpr_id(ID,_) :- add_error_fail(def_get_texpr_id,'Could not extract identifier, not properly wrapped: ',ID).
259
260 % translate a list of ids with the b/3 wrapper into a plain id list; throw error if not an identifier
261 % used to also be called get_texpr_id_names
262 def_get_texpr_ids(L,Ids) :- maplist(def_get_texpr_id,L,Ids).
263
264 create_typed_id(IDName,Type,b(identifier(IDName),Type,[])).
265
266 create_typed_ids([],[],[]).
267 create_typed_ids([ID|TI],[Type|TT],[TID| TRes]) :-
268 create_typed_id(ID,Type,TID),
269 create_typed_ids(TI,TT,TRes).
270
271 same_id(X,Y,ID) :- get_texpr_id(X,ID), get_texpr_id(Y,ID).
272
273 same_ids([],[]).
274 same_ids([X|Xs],[Y|Ys]) :- same_id(X,Y,_), same_ids(Xs,Ys).
275
276 % check if two lists of identifiers have the same name and types
277 same_ids_and_types([],[]).
278 same_ids_and_types([b(identifier(Id),T1,_)|Xs],[b(identifier(Id),T2,_)|Ys]) :- unify_types_strict(T1,T2),
279 same_ids_and_types(Xs,Ys).
280
281 % split a list of typed identifiers into atomic ids and types
282 split_names_and_types([],N,T) :- !, N=[], T=[].
283 split_names_and_types([Identifier|IdRest],[Name|NRest],[Type|TRest]) :- !,
284 def_get_texpr_id(Identifier,Name),
285 get_texpr_type(Identifier,Type),
286 split_names_and_types(IdRest,NRest,TRest).
287 split_names_and_types(TIDS,N,R) :-
288 add_internal_error('Illegal call to:',split_names_and_types(TIDS,N,R)),fail.
289
290
291
292 % check if two wrapped expressions are equal (modulo associated Info, e.g. source loc info)
293 same_texpr(b(E1,Type,_),b(E2,Type,_)) :- % should we do a == check first ?? probably not as it may traverse the entire structure (see email exchange with SICStus 28.1.2015)
294 same_functor(E1,E2),
295 safe_syntaxelement_det(E1,Subs1,_Names1,_List1,Constant),
296 safe_syntaxelement_det(E2,Subs2,_Names2,_List2,Constant2),
297 Constant==Constant2, % in case we have values with variables inside !
298 same_sub_expressions(Subs1,Subs2).
299
300 same_sub_expressions([],[]).
301 same_sub_expressions([H1|T1],[H2|T2]) :- same_texpr(H1,H2), same_sub_expressions(T1,T2).
302
303 % check if two wrapped expressions definitely denote a different value (and are well-defined)
304 % only detects certain cases !
305 different_texpr_values(b(E1,Type,I1),b(E2,Type,I2)) :-
306 different_value(E1,E2,CheckWD),
307 (CheckWD=false -> true
308 ; always_well_defined_or_wd_improvements_allowed(b(E1,Type,I1)),
309 always_well_defined_or_wd_improvements_allowed(b(E2,Type,I2))).
310 different_value(boolean_false,boolean_true,false) :- !.
311 different_value(boolean_true,boolean_false,false) :- !.
312 different_value(integer(X),IY,false) :- get_integer_aux(IY,Y),!, X\=Y.
313 different_value(string(X),string(Y),false) :- !, X\=Y.
314 different_value(value(VX),Y,false) :- !, different_val_from(VX,Y).
315 different_value(empty_set,S,check_wd) :- !, non_empty_set(S).
316 different_value(S,empty_set,check_wd) :- !, non_empty_set(S).
317 % should we compare two set_extensions ? couples ? records ? reals/floats?
318
319 different_val_from(Var,_) :- var(Var),!,fail.
320 different_val_from(int(X),IY) :- integer(X), get_integer_aux(IY,Y), X\=Y.
321 different_val_from(fd(X,Gs),value(FY)) :- nonvar(X), nonvar(FY), FY=fd(Y,Gs), nonvar(Y), X\=Y.
322 different_val_from(pred_false,boolean_true).
323 different_val_from(pred_false,value(BY)) :- BY==pred_true.
324 different_val_from(pred_true,boolean_false).
325 different_val_from(pred_true,value(BY)) :- BY==pred_false.
326 different_val_from(string(X),string(Y)) :- !, X\=Y.
327 different_val_from(string(X),value(VY)) :- nonvar(VY), VY=string(Y), nonvar(Y), !, X\=Y.
328 different_val_from(avl_set(node(_,_,_,_,_)),empty_set).
329
330 non_empty_set(set_extension([_|_])).
331 non_empty_set(sequence_extension([_|_])).
332
333
334 get_texpr_exprs([],[]).
335 get_texpr_exprs([E|Rest],[N|NRest]) :- get_texpr_expr(E,N),get_texpr_exprs(Rest,NRest).
336 get_texpr_exprs(b(E,_,_),Res) :- add_internal_error('Illegal call:',get_texpr_infos(b(E,_,_),Res)), Res=[E].
337 get_texpr_types([],[]).
338 get_texpr_types([E|Rest],[T|TRest]) :- get_texpr_type(E,T),get_texpr_types(Rest,TRest).
339 get_texpr_types(b(_,T,_),Res) :- add_internal_error('Illegal call:',get_texpr_infos(b(_,T,_),Res)), Res=[T].
340 get_texpr_infos([],[]).
341 get_texpr_infos([E|Rest],[I|IRest]) :- get_texpr_info(E,I),get_texpr_infos(Rest,IRest).
342 get_texpr_infos(b(_,_,I),Res) :- add_internal_error('Illegal call:',get_texpr_infos(b(_,_,I),Res)), Res=[I].
343 get_texpr_ids([],[]).
344 get_texpr_ids([E|Rest],[I|IRest]) :- get_texpr_id(E,I),get_texpr_ids(Rest,IRest).
345
346 get_texpr_pos(TExpr,Pos) :-
347 get_texpr_info(TExpr,Infos),
348 ? ( member(nodeid(Pos1),Infos) -> !,Pos=Pos1
349 ; Pos = none).
350
351 get_texpr_pos_infos(b(_,_,Infos),PosInfos) :- extract_pos_infos(Infos,PosInfos).
352
353 % similar to get_texpr_pos, but returns sub-list of infos relating to position
354 extract_pos_infos(Infos,InfoRes) :-
355 ? ( member(nodeid(Pos1),Infos) -> !,InfoRes=[nodeid(Pos1)]
356 ; InfoRes = []).
357
358 % copy position info from first arg to second argument
359 copy_pos_infos(b(_,_,Infos1),Arg2,Res) :-
360 member(nodeid(Pos1),Infos1),!,
361 Arg2 = b(E,T,Infos2), Res = b(E,T,Infos3),
362 delete_pos_info(Infos2,Infos2d),
363 Infos3 = [nodeid(Pos1)|Infos2d].
364 copy_pos_infos(_,TE,TE).
365
366 delete_pos_info(Infos1,Infos2) :-
367 select(nodeid(_),Infos1,D),!, Infos2=D.
368 %delete(Infos1,nodeid(_),Infos2).
369 delete_pos_info(I,I).
370
371 % propagate position info from second list to first one if it has better position info
372 propagate_pos_info_if_useful(Infos,AuxInfos,NewInfos) :-
373 member(nodeid(Pos2),AuxInfos),
374 \+ derived_pos(Pos2),!, % potentially useful position info to propagate
375 (select(nodeid(Pos1),Infos,Infos2)
376 -> (derived_pos(Pos1)
377 -> NewInfos = [nodeid(Pos2)|Infos2] % we have better position info now
378 ; NewInfos = Infos % we already have a position info
379 )
380 ; NewInfos = [nodeid(Pos2)|Infos]
381 ).
382 propagate_pos_info_if_useful(Infos,_,Infos).
383
384 % derived position; not precise instrinsic label at top-level
385 derived_pos(rodin_derived_context_pos(_,_,_)).
386
387
388 get_info_pos(Infos,Pos) :- (member(nodeid(Pos1),Infos) -> Pos=Pos1 ; Pos=none).
389 contains_info_pos(Infos) :- (member(nodeid(NI),Infos) -> NI \= none).
390
391 create_texpr(Expr,Type,Info,b(Expr,Type,Info)).
392
393 add_texpr_infos(b(Expr,Type,Old),Infos,b(Expr,Type,New)) :- !,
394 append(Infos,Old,New).
395 add_texpr_infos(Other,Infos,Res) :-
396 add_internal_error('Illegal call, not BExpr:',add_texpr_infos(Other,Infos,Res)),fail.
397
398 add_texpr_info_if_new(b(Expr,Type,Old),Info,b(Expr,Type,New)) :- !,
399 add_info_if_new(Old,Info,New).
400 add_texpr_info_if_new(Other,Infos,Res) :-
401 add_internal_error('Illegal call, not BExpr:',add_texpr_info_if_new(Other,Infos,Res)),fail.
402 % add multiple infos:
403 add_texpr_infos_if_new(b(Expr,Type,Old),Infos,b(Expr,Type,New)) :-
404 add_infos_if_new(Infos,Old,New).
405
406 % add to info list:
407 add_info_if_new(Old,Info,New) :-
408 (member(Info,Old) -> New=Old ; New = [Info|Old]).
409
410 add_infos_if_new([]) --> [].
411 add_infos_if_new([Info|T]) --> add_info(Info), add_infos_if_new(T).
412 add_info(Info,Old,New) :-
413 (member(Info,Old) -> New=Old ; New = [Info|Old]).
414
415
416 % try and extract the Rodin name of a predicate or expression
417 get_rodin_name(Expression,Name) :- get_texpr_pos(Expression,rodinpos(Name,_)), Name \= [].
418 get_rodin_name(Expression,Name) :- get_texpr_pos(Expression,rodinpos(_Model,Name,_)), Name \= []. % new rodinpos
419
420 get_rodin_model_name(Expression,Model) :-
421 get_texpr_pos(Expression,rodinpos(Model,Name,_)), Name \= []. % new rodinpos
422 % Note: only precise position label, not rodin_derived_context_pos
423
424 % try and extract the Rodin name or label pragma of a predicate or expression
425 get_texpr_labels(TExpr,Label) :-
426 get_texpr_info(TExpr,Infos),
427 member(I,Infos), info_label(I,Label).
428 get_info_labels(Infos,LabelList) :-
429 ? member(I,Infos), info_label(I,LabelList).
430 select_info_labels(LabelList,Infos,Rest) :-
431 select(I,Infos,Rest), info_label(I,LabelList).
432 info_label(nodeid(NodeID),[Name]) :- nodeid_info_label(NodeID,Name).
433 info_label(label(LabelList),LabelList).
434
435 nodeid_info_label(rodinpos(Name,_),Name) :- Name \= [].
436 nodeid_info_label(rodinpos(Model,Name,_),FullName) :- Name \= [], % new rodinpos
437 ajoin([Model,':',Name], FullName). % TO DO: if only one level; don't do this
438 % TODO: provide separate way to access this derived information:
439 %nodeid_info_label(rodin_derived_context_pos(Model,Context,Label),FullName) :-
440 % ajoin([Model,'.',Context,':',Label], FullName).
441
442
443 add_labels_to_texpr(E,[],R) :- !, R=E. % no labels to add
444 add_labels_to_texpr(b(E,T,I),Labels,b(E,T,NewI)) :-
445 (select(label(OldList),I,Rest)
446 -> append(Labels,OldList,NewList), NewI=[label(NewList)|Rest]
447 % TO DO: what if we have Rodin labels
448 ; NewI = [label(Labels)|I]
449 ).
450
451 get_texpr_label(TExpr,Label) :- get_texpr_labels(TExpr,Labels), member(Label,Labels).
452
453 get_texpr_description(TExpr,Description) :-
454 get_texpr_info(TExpr,Infos),
455 memberchk(description(Description),Infos).
456
457 add_texpr_description(b(E,T,I),Description,b(E,T,[description(Description)|I])) :-
458 (atom(Description) -> true ;
459 add_error(add_texpr_description,'Non-atomic description:',Description)).
460
461 % check if an info list has an ignore pragma
462 info_has_ignore_pragma(Infos) :-
463 member(description('prob-ignore'),Infos).
464 % detect_prob_ignore ast_cleanup rule also generates this description annotation
465
466 predicate_has_ignore_pragma(b(_E,pred,I)) :-
467 %add_message(check_prob_ignore,'Pred: ',b(_E,pred,I),I),
468 info_has_ignore_pragma(I).
469
470 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
471
472 :- assert_must_succeed( (E = "1/2",
473 bmachine:b_parse_machine_expression_from_codes(E,ET,Type,false,Err),
474 Type==integer, Err==none, always_well_defined(ET) ) ).
475 :- assert_must_succeed( (E = "3 mod 2",
476 bmachine:b_parse_machine_expression_from_codes(E,ET,Type,false,Err),
477 Type==integer, Err==none, always_well_defined(ET) ) ).
478 :- assert_must_succeed( (E = "1/0",
479 bmachine:b_parse_machine_expression_from_codes(E,ET,Type,false,Err),
480 Type==integer, Err==none, \+ always_well_defined(ET) ) ).
481 :- assert_must_succeed( (E = "2*(3 mod card({}))",
482 bmachine:b_parse_machine_expression_from_codes(E,ET,Type,false,Err),
483 Type==integer, Err==none, \+ always_well_defined(ET) ) ).
484 :- assert_must_succeed( (E = "1/(2+1-3)",
485 bmachine:b_parse_machine_expression_from_codes(E,ET,Type,false,Err),
486 Type==integer, Err==none, \+ always_well_defined(ET) ) ).
487 :- assert_must_succeed( (E = "max({1,2,3,0})",
488 bmachine:b_parse_machine_expression_from_codes(E,ET,Type,false,Err),
489 Type==integer, Err==none, always_well_defined(ET) ) ).
490 :- assert_must_succeed( (E = "min({1,2,3,0})",
491 bmachine:b_parse_machine_expression_from_codes(E,ET,Type,false,Err),
492 Type==integer, Err==none, always_well_defined(ET) ) ).
493 :- assert_must_succeed( (E = "min({1,2,3,0}-(0..4))",
494 bmachine:b_parse_machine_expression_from_codes(E,ET,Type,false,Err),
495 Type==integer, Err==none, \+ always_well_defined(ET) ) ).
496 :- assert_must_succeed( (E = "2+max({1,2,3, 1/0})",
497 bmachine:b_parse_machine_expression_from_codes(E,ET,Type,false,Err),
498 Type==integer, Err==none,\+ always_well_defined(ET) ) ).
499 :- assert_must_succeed( (E = "2-card({1,2,3})",
500 bmachine:b_parse_machine_expression_from_codes(E,ET,Type,false,Err),
501 Type==integer, Err==none, always_well_defined(ET) ) ).
502 :- assert_must_succeed( (E = "2-card({1,2,3, 1/0})",
503 bmachine:b_parse_machine_expression_from_codes(E,ET,Type,false,Err),
504 Type==integer, Err==none,\+ always_well_defined(ET) ) ).
505 :- assert_must_succeed( (E = "bool(2-size([1,2,3, 1/0])=3)",
506 bmachine:b_parse_machine_expression_from_codes(E,ET,Type,false,Err),
507 Type==boolean, Err==none, \+ always_well_defined(ET) ) ).
508 :- assert_must_succeed( (E = "bool(2-size([1,2,3, 1/2, 3 mod 2, 3**2])=size([]))",
509 bmachine:b_parse_machine_expression_from_codes(E,ET,Type,false,Err),
510 Type==boolean, Err==none, always_well_defined(ET) ) ).
511
512 always_well_defined_or_wd_reorderings_allowed(BE) :- % allow re-ordering to improve Left-to-right WD
513 (preferences:preference(disprover_mode,true) -> true % we can assume all calls are well-defined
514 ; preferences:preference(allow_improving_wd_mode,true) -> true
515 ; preferences:preference(data_validation_mode,true) -> true
516 ; always_well_defined_or_discharged(BE)).
517 always_well_defined_or_wd_improvements_allowed(BE) :- % allow to remove useless calls which could be non-WD
518 % example #x(x = f(...)) -> btrue or f[{}] --> {}
519 always_well_defined_or_wd_reorderings_allowed(BE). % we currently use the same definition
520 always_well_defined_or_disprover_mode(BE) :-
521 (preferences:preference(disprover_mode,true) -> true % we can assume all calls are well-defined
522 ; always_well_defined_or_discharged(BE)).
523
524 always_well_defined_or_discharged(b(E,_,Infos)) :- !,
525 (nonmember(contains_wd_condition,Infos) -> true
526 ; always_wd(E) -> true % some special rules
527 ; member(discharged_wd_po,Infos) -> true
528 %; nl, functor(E,F,N), F \= function, print(non_wd(F,N)),nl,nl,fail
529 ).
530 always_well_defined_or_discharged(E) :-
531 add_error_fail(always_well_defined,'Illegal call: ',always_well_defined_or_discharged(E)).
532
533 % should ensure that there is no failure and no error raised
534 always_well_defined(b(E,_,Infos)) :- !,
535 (nonmember(contains_wd_condition,Infos) -> true
536 ; always_wd(E) -> true % some special rules
537 %; nl, functor(E,F,N), F \= function, print(non_wd(F,N)),nl,nl,fail
538 ).
539 always_well_defined(E) :- add_error_fail(always_well_defined,'Illegal call: ',always_well_defined(E)).
540
541
542 :- assert_must_succeed( always_wd(div( b(integer(2),integer,[]), b(integer(2),integer,[]) )) ).
543 :- assert_must_fail( always_wd(div( b(integer(2),integer,[]), b(integer(0),integer,[]) )) ).
544 :- assert_must_succeed( always_wd(modulo( b(integer(2),integer,[]), b(integer(2),integer,[]) )) ).
545 :- assert_must_fail( always_wd(modulo( b(integer(2),integer,[]), b(integer(0),integer,[]) )) ).
546 :- assert_must_fail( always_wd(modulo( b(integer(2),integer,[]), b(integer(-2),integer,[]) )) ).
547 :- assert_must_fail( always_wd(modulo( b(integer(-1),integer,[]), b(integer(2),integer,[]) )) ).
548 :- assert_must_succeed( always_wd(power_of( b(integer(2),integer,[]), b(integer(3),integer,[]) )) ).
549 :- assert_must_succeed( always_wd(power_of( b(integer(2),integer,[]), b(integer(0),integer,[]) )) ).
550 :- assert_must_fail( always_wd(power_of( b(integer(2),integer,[]), b(integer(-1),integer,[]) )) ).
551
552 % catch cases where the construct is currently so instantiated that we can determine that it is well-defined
553 % can happen e.g. during closure compilation
554 :- use_module(custom_explicit_sets,[check_unique_in_domain_of_avlset/2]).
555 :- use_module(kernel_tools,[ground_value/1]).
556 always_wd(power_of(X,Y)) :- get_integer(Y,Val), Val>=0,
557 (eventb_mode -> get_integer(X,ValX), ValX >=0
558 ; always_well_defined(X)).
559 always_wd(div(X,Y)) :- get_integer(Y,Val), Val\=0, always_well_defined(X).
560 always_wd(modulo(X,Y)) :- get_integer(Y,Val), Val>0, % Z Live allows negative numbers here it seems, cf modulo2
561 (z_or_tla_minor_mode -> true % in Z, TLA we can have negative numbers here
562 ; get_integer(X,ValX), ValX>=0).
563 always_wd(function(X,Y)) :- nonvar(X),
564 X= b(value(AVLSET),_,_), nonvar(AVLSET), AVLSET=avl_set(AVL),
565 always_wd_avl_function(AVL,Y).
566 always_wd(min(X)) :- non_empty_finite_wd_set_value(X).
567 always_wd(max(X)) :- non_empty_finite_wd_set_value(X).
568 always_wd(card(X)) :- finite_wd_set_value(X).
569 always_wd(size(X)) :- finite_wd_seq_value(X).
570 always_wd(first(X)) :- non_empty_wd_seq_value(X).
571 always_wd(front(X)) :- non_empty_wd_seq_value(X).
572 always_wd(last(X)) :- non_empty_wd_seq_value(X).
573 always_wd(tail(X)) :- non_empty_wd_seq_value(X). % TO DO: add restrict_front, restrict_tail ?
574 always_wd(general_intersection(X)) :- non_empty_finite_wd_set_value(X).
575 always_wd(value(_)). % we have already computed the value and will raise WD error; to be 100 % safe we could restrict this to ground values
576 % other candidates: size(_), first(_) last(_) tail(_) front(_) restrict_front(_,_) restrict_tail(_,_) rel_iterate(_,_)
577 always_wd(typeset).
578 % operators that are always wd on their own:
579 always_wd(record_field(RecEx,FieldName)) :- ground(FieldName),
580 always_well_defined(RecEx).
581 always_wd(unary_minus(A)) :- always_well_defined(A).
582 always_wd(unary_minus_real(A)) :- always_well_defined(A).
583 always_wd(first_of_pair(A)) :- always_well_defined(A).
584 always_wd(add(A,B)) :- always_well_defined(A),always_well_defined(B).
585 always_wd(add_real(A,B)) :- always_well_defined(A),always_well_defined(B).
586 always_wd(minus(A,B)) :- always_well_defined(A),always_well_defined(B).
587 always_wd(minus_real(A,B)) :- always_well_defined(A),always_well_defined(B).
588 always_wd(multiplication(A,B)) :- always_well_defined(A),always_well_defined(B).
589 always_wd(multiplication_real(A,B)) :- always_well_defined(A),always_well_defined(B).
590 always_wd(equal(A,B)) :- always_well_defined(A),always_well_defined(B).
591 always_wd(not_equal(A,B)) :- always_well_defined(A),always_well_defined(B).
592 always_wd(less_equal(A,B)) :- always_well_defined(A),always_well_defined(B).
593 always_wd(less_equal_real(A,B)) :- always_well_defined(A),always_well_defined(B).
594 always_wd(greater_equal(A,B)) :- always_well_defined(A),always_well_defined(B).
595 always_wd(less(A,B)) :- always_well_defined(A),always_well_defined(B).
596 always_wd(less_real(A,B)) :- always_well_defined(A),always_well_defined(B).
597 always_wd(greater(A,B)) :- always_well_defined(A),always_well_defined(B).
598 always_wd(couple(A,B)) :- always_well_defined(A),always_well_defined(B).
599 % TO DO: add more/all other operators ?
600
601 always_wd_avl_function(AVL,Y) :- nonvar(Y), Y= b(value(Val),_,_),
602 ground_value(Val), !,
603 % Warning: this does not check that the whole AVL is a function; just this particular lookup is ok
604 check_unique_in_domain_of_avlset(Val,AVL). % ,print(ok),nl.
605 always_wd_avl_function(AVL,Y) :- always_well_defined(Y),
606 custom_explicit_sets:quick_definitely_maximal_total_function_avl(AVL).
607
608 % non empty set with WD elements
609 non_empty_finite_wd_set_value(b(E,_,_)) :- non_empty_fin_wd_set2(E).
610 non_empty_fin_wd_set2(bool_set).
611 non_empty_fin_wd_set2(value(X)) :- definitely_not_empty_finite_value(X).
612 non_empty_fin_wd_set2(set_extension(S)) :- l_always_well_defined(S). % the set_extension could contain wd_errors !!
613 non_empty_fin_wd_set2(sequence_extension(S)) :- l_always_well_defined(S). % ditto
614 non_empty_fin_wd_set2(interval(A,B)) :- get_integer(A,IA), get_integer(B,IB), IA =< IB.
615 % see not_empty_set_aux
616 definitely_not_empty_finite_value(X) :- var(X),!,fail.
617 definitely_not_empty_finite_value(avl_set(_)).
618 definitely_not_empty_finite_value([_|_]).
619 definitely_not_empty_finite_value(closure(P,T,B)) :-
620 custom_explicit_sets:is_interval_closure(P,T,B,LOW,UP), integer(LOW),integer(UP), LOW =< UP.
621 % TODO: pow_subset of finite values
622
623 non_empty_wd_seq_value(b(E,_,_)) :- non_empty_seq2(E).
624 non_empty_seq2(value(X)) :- definitely_not_empty_seq(X).
625 non_empty_seq2(sequence_extension(S)) :- l_always_well_defined(S), S=[_|_].
626
627 definitely_not_empty_seq(X) :- var(X),!,fail.
628 definitely_not_empty_seq(avl_set(A)) :- custom_explicit_sets:is_avl_sequence(A).
629 definitely_not_empty_seq([El1|T]) :- T==[],nonvar(El1), El1=(IDX,_), IDX==int(1). % TO DO: add more cases ?
630
631
632 finite_set_or_disprover_mode(Set) :-
633 (preferences:preference(disprover_mode,true) -> true % we can assume all calls are well-defined
634 ; finite_wd_set_value(Set)).
635
636 :- use_module(typing_tools,[is_provably_finite_type/1]).
637 % we could also use is_finite_type_in_context to allow deferred sets to be counted as finite
638 finite_wd_set_value(b(E,T,_)) :- !, (finite_set2(E) -> true ; is_provably_finite_type(T)).
639 finite_wd_set_value(E) :- add_internal_error('Not a BExpr: ',E),fail.
640 finite_set2(empty_set).
641 finite_set2(empty_sequence).
642 finite_set2(value(X)) :- X==[] -> true ; definitely_not_empty_finite_value(X).
643 finite_set2(set_extension(S)) :- l_always_well_defined(S). % the set_extension could contain wd_errors !!
644 finite_set2(sequence_extension(S)) :- l_always_well_defined(S). % ditto
645
646 finite_wd_seq_value(b(E,_,_)) :- finite_seq2(E).
647 finite_seq2(empty_set).
648 finite_seq2(empty_sequence).
649 finite_seq2(value(X)) :- finite_seq_value(X).
650 finite_seq2(sequence_extension(S)) :- l_always_well_defined(S).
651
652 finite_seq_value(X) :- var(X),!,fail.
653 finite_seq_value([]).
654 finite_seq_value(avl_set(A)) :- custom_explicit_sets:is_avl_sequence(A).
655 % it could be expensive to check if non empty list is a B sequence ??
656
657 l_always_well_defined([]).
658 l_always_well_defined([H|T]) :- always_well_defined(H), l_always_well_defined(T).
659
660 is_truth(b(F,pred,_)) :- is_truth_aux(F).
661 is_truth_aux(truth).
662 is_truth_aux(value(V)) :- V==pred_true. % can occur in CSE mode
663
664 is_falsity(b(F,pred,_)) :- is_falsity_aux(F).
665 is_falsity_aux(falsity).
666 is_falsity_aux(value(V)) :- V==pred_false. % can occur in CSE mode
667
668 % conjunction of a list of predicates
669 % NOTE: bsyntaxtree:conjunct_predicates([P1,P2,P3],R). --> generates R = b(conjunct(b(conjunct(P1,P2),pred,[]),P3),pred,[])
670 conjunct_predicates(V,R) :- var(V),!, add_internal_error('Variable conjunction list: ',conjunct_predicates(V,R)),fail.
671 conjunct_predicates([],b(truth,pred,[])).
672 conjunct_predicates([P|Rest],Result) :- conjunct2(Rest,P,Result).
673 conjunct2([],P,P).
674 conjunct2([Q|Rest],P,Result) :- conjunct3(P,Q,R), conjunct2(Rest,R,Result).
675 conjunct3(b(truth,_,_),P,P) :- !.
676 conjunct3(P,b(truth,_,_),P) :- !.
677 conjunct3(A,B,b(conjunct(A,B),pred,NewInfo)) :- extract_info(A,B,NewInfo).
678
679 % disjunction of a list of predicates
680 disjunct_predicates([],b(falsity,pred,[])).
681 disjunct_predicates([P|Rest],Result) :- disjunct2(Rest,P,Result).
682 disjunct2([],P,P).
683 disjunct2([Q|Rest],P,Result) :- disjunct3(P,Q,R), disjunct2(Rest,R,Result).
684 disjunct3(b(falsity,_,_),P,R) :- !, R=P.
685 disjunct3(b(truth,T,I),_,R) :- !, R=b(truth,T,I).
686 disjunct3(P,b(falsity,_,_),R) :- !, R=P.
687 disjunct3(_,b(truth,T,I),R) :- !, R=b(truth,T,I).
688 disjunct3(A,B,b(disjunct(A,B),pred,NewInfo)) :- extract_info(A,B,NewInfo).
689
690 % conjunct two predicates and try and construct position information
691 conjunct_predicates_with_pos_info(A,B,AB) :- is_truth(B),!, AB=A.
692 conjunct_predicates_with_pos_info(A,B,AB) :- is_truth(A),!, AB=B.
693 conjunct_predicates_with_pos_info(A,B,AB) :-
694 conjunct_predicates([A,B],AB0), % this may contain position info if B is truth; hence we do check above
695 (try_get_merged_position_info(A,B,ABI)
696 -> add_texpr_infos(AB0,[ABI],AB) %,print(abi(ABI)),nl
697 ; AB=AB0).
698
699 % disjunct two predicates and try and construct position information
700 disjunct_predicates_with_pos_info(A,B,AB) :-
701 disjunct_predicates([A,B],AB0),
702 (try_get_merged_position_info(A,B,ABI)
703 -> add_texpr_infos(AB0,[ABI],AB) %,print(abi(ABI)),nl
704 ; AB=AB0).
705
706 try_get_merged_position_info(b(_,_,I1),b(_,_,I2),PosInfo) :-
707 (try_get_merged_position_info_aux(I1,I2,MergedInfo) -> PosInfo = MergedInfo
708 ; get_non_label_posinfo(Pos1,I1) -> PosInfo=nodeid(Pos1)
709 ; get_non_label_posinfo(Pos2,I2) -> PosInfo=nodeid(Pos2)
710 ).
711 try_get_merged_position_info_aux(I1,I2,nodeid(pos(C,Filenumber,Srow,Scol,Erow,Ecol))) :-
712 member(nodeid(pos(C1,Filenumber,Srow1,Scol1,Erow1,Ecol1)),I1),
713 (number(C1),number(Srow1),number(Scol1),number(Erow1),number(Ecol1)
714 -> true ; add_internal_error('Info field 1 not yet instantiated: ',try_get_merged_position_info(I1)),fail),
715 !,
716 member(nodeid(pos(C2,Filenumber,Srow2,Scol2,Erow2,Ecol2)),I2),
717 (number(C2),number(Srow2),number(Scol2),number(Erow2),number(Ecol2)
718 -> true ; add_internal_error('Info field 2 not yet instantiated: ',try_get_merged_position_info(I2)),fail),
719 !,
720 % merge position info if in same file
721 (C1 =< C2 -> C=C1, Srow=Srow1,Scol=Scol1 ; C=C2, Srow=Srow2,Scol=Scol2),
722 ((Erow1 > Erow2 ; Erow1=Erow2, Ecol1 >= Ecol2)
723 -> Erow =Erow1, Ecol=Ecol1
724 ; Erow =Erow2, Ecol=Ecol2).
725
726 % get position info which is not a label; label info should not be propagated to outer conjuncts/disjuncts/...
727 get_non_label_posinfo(Pos,Infos) :- member(nodeid(Pos),Infos),
728 \+ functor(Pos,rodinpos,_).
729
730 get_texpr_non_label_posinfo(b(_,_,Infos),nodeid(Pos)) :- get_non_label_posinfo(Pos,Infos).
731
732 % conjunct list of predicates and try and construct position information
733 conjunct_predicates_with_pos_info([H|T],Res) :- is_truth(H),!,
734 (T=[] -> Res = H ; conjunct_predicates_with_pos_info(T,Res)).
735 conjunct_predicates_with_pos_info([H|T],Res) :-
736 last_non_truth(T,none,Last), % the truth elements will be removed and are not relevant; get last relevant predicate
737 Last \= none,
738 try_get_merged_position_info(H,Last,MergedPosInfo), % try and merge position of first and last element
739 !,
740 conjunct_predicates([H|T],Res0),
741 add_texpr_infos(Res0,[MergedPosInfo],Res). % Res0 should have no nodeid field
742 conjunct_predicates_with_pos_info(L,Res) :- conjunct_predicates(L,Res).
743
744 :- assert_must_succeed((bsyntaxtree:last_non_truth([a,b,c],none,L),L==c)).
745 :- assert_must_succeed((bsyntaxtree:last_non_truth([a,b,c,b(truth,pred,[])],none,L),L==c)).
746
747 % get last non-truth element and filter out all truth elements
748 last_non_truth([],Acc,Acc).
749 last_non_truth([H|T],NonTruth,Last) :- is_truth(H),!, last_non_truth(T,NonTruth,Last).
750 last_non_truth([H|T],_,Last) :- last_non_truth(T,H,Last).
751
752
753 texpr_contains_wd_condition(b(_,_,Info)) :- !, memberchk(contains_wd_condition,Info).
754 texpr_contains_wd_condition(E) :- add_internal_error('Not a texpr: ',texpr_contains_wd_condition(E)).
755
756 % a version of create_texpr which collects automatically important infos from sub-expressions
757 safe_create_texpr(Expr,Type,b(Expr,Type,Info)) :- %
758 ? (sub_expression_contains_wd_condition(Expr) -> Info = [contains_wd_condition] ; Info=[]).
759
760 safe_create_texpr(Expr,Type,Info,b(Expr,Type,FullInfo)) :- %
761 ((sub_expression_contains_wd_condition(Expr), nonmember(contains_wd_condition, Info)) -> FullInfo = [contains_wd_condition|Info] ; FullInfo=Info).
762
763 ?sub_expression_contains_wd_condition(Expr) :- sub_expression_contains_wd_condition(Expr,_).
764 sub_expression_contains_wd_condition(Expr,Sub) :-
765 safe_syntaxelement_det(Expr,Subs,_Names,_L,_C),
766 ? member(b(Sub,_,Infos),Subs),
767 (var(Infos)
768 -> add_internal_error('Typed expression not sufficiently instantiated (variable Infos): ',sub_expression_contains_wd_condition(Expr)),
769 fail
770 ; memberchk(contains_wd_condition,Infos)).
771
772 % provide updated infos (e.g., reads(...)) and remove any old info fields with same functor
773 update_infos([],Infos,Infos).
774 update_infos([Update|T],OldInfos,NewInfos) :-
775 functor(Update,F,N),
776 functor(Old,F,N),
777 delete(OldInfos,Old,OldInfos1),
778 update_infos(T,[Update|OldInfos1],NewInfos).
779
780 % merge two info lists and try to reconcile position information:
781 merge_info(Info1,Info2,Res) :-
782 merge_imp_info2(Info2,Info1,NewInfo),
783 (try_get_merged_position_info_aux(Info1,Info2,NewPos)
784 -> delete_pos_info(NewInfo,NI2),
785 Res = [NewPos|NI2]
786 ; Res = NewInfo).
787
788 % extract important info but without used_ids:
789 extract_info_wo_used_ids(b(_,_,Info1),Info) :-
790 extract_pos_infos(Info1,PosInfos),
791 extract_just_important_info_aux(Info1,[],I1),
792 append(PosInfos,I1,Info).
793 extract_info_wo_used_ids_and_pos(b(_,_,Info1),b(_,_,Info2),Info) :-
794 extract_just_important_info_aux(Info1,[],I1),
795 extract_just_important_info_aux(Info2,I1,Info).
796
797 % extract important info from one sub-expression:
798 extract_info(b(_,_,Info1),NewInfo) :-
799 extract_imp_info1(Info1,I1),!, NewInfo = I1.
800 extract_info(A,R) :-
801 add_internal_error('Could not extract info: ',extract_info(A,R)),
802 R=[].
803 % extract imortant info fields from two (sub-)expressions
804 extract_info(b(_,_,Info1),b(_,_,Info2),NewInfo) :-
805 merge_imp_info2(Info1,Info2,II),!, NewInfo = II.
806 %:- use_module(library(ordsets),[ord_intersection/3]).
807 % ord_intersection(Info1,Info2,NewInfo),!.
808 % TO DO: should we merge nodeid position information !?
809 extract_info(A,B,R) :- add_internal_error('Could not extract info: ',extract_info(A,B,R)),
810 R=[].
811
812 % extract important info and used_ids
813 extract_imp_info1([],[]).
814 extract_imp_info1([H|T],Res) :-
815 ((important_info(H); H=used_ids(_)) -> Res=[H|ET], extract_imp_info1(T,ET)
816 ; extract_imp_info1(T,Res)
817 ).
818
819 % extract and merge important info and try to merge used_ids from two info lists
820 merge_imp_info2(Info1,Info2,ResInfos) :-
821 extract_imp_info1(Info1,I1),
822 extract_imp_info1(Info2,I2),
823 merge_aux(I1,I2,ResInfos).
824
825 merge_aux([],I2,Res) :- !, delete(I2,used_ids(_),Res). % used_ids not valid for new construct
826 merge_aux(I1,[],Res) :- !, delete(I1,used_ids(_),Res). % ditto
827 merge_aux(I1,I2,ResInfos) :-
828 ? (select(used_ids(Ids1),I1,II1)
829 ? -> (select(used_ids(Ids2),I2,II2)
830 -> ord_union(Ids1,Ids2,Ids3),
831 append(II1,[used_ids(Ids3)|II2],II)
832 ; append(II1,I2,II)
833 )
834 ; delete(I2,used_ids(_),II2),
835 append(I1,II2,II)
836 ),
837 sort(II,ResInfos). % TO DO: sort sublists ? and use ord_union?
838
839 important_info(contains_wd_condition).
840 important_info(prob_annotation(_)).
841 important_info(allow_to_lift_exists).
842 important_info(removed_typing).
843 %important_info(lambda_result(_)). % should probably not be copied
844
845 % variation of above which does not extract and merge used_ids:
846 extract_just_important_info_aux([],Acc,Acc).
847 extract_just_important_info_aux([H|T],Acc,Res) :-
848 (important_info(H), \+ member(H,Acc) -> extract_just_important_info_aux(T,[H|Acc],Res)
849 ; extract_just_important_info_aux(T,Acc,Res)).
850
851
852 is_a_conjunct(b(conjunct(A,B),pred,_),A,B).
853 % use is_a_conjunct_without_label if you want to avoid decomposing conjunction associated with a single label
854 is_a_conjunct_without_label(b(conjunct(A,B),pred,I),A,B) :- \+ get_info_labels(I,_).
855 % use decompose conjunct if you want to propagate labels down to the conjuncts
856 decompose_conjunct(b(conjunct(A,B),pred,I),ResA,ResB) :-
857 (get_info_labels(I,Labels)
858 -> add_labels_to_texpr(A,Labels,ResA), add_labels_to_texpr(B,Labels,ResB)
859 ; ResA=A, ResB=B).
860
861 size_of_conjunction(C,Size) :- size_of_conjunction(C,0,Size).
862 size_of_conjunction(C,Acc,Res) :- is_a_conjunct(C,A,B),!,
863 size_of_conjunction(B,Acc,A1),
864 size_of_conjunction(A,A1,Res).
865 size_of_conjunction(_,Acc,Size) :- Size is Acc+1.
866
867 conjunction_to_list(C,L) :- var(C),!,
868 add_error_fail(conjunction_to_list,'Internal error: var :',conjunction_to_list(C,L)).
869 conjunction_to_list(C,List) :-
870 conjunction_to_list2(C,List,[]).
871 conjunction_to_list2(X,I,O) :- X=b(E,_,_),
872 (E=conjunct(LHS,RHS) -> conjunction_to_list2(LHS,I,Inter),
873 conjunction_to_list2(RHS,Inter,O)
874 ; E = truth -> I=O
875 ; I = [X|O]).
876
877 % a variation of conjunction_to_list which propagates Rodin and pragma label infos down
878 % important for proof info; maybe we should only propagate Rodin labels ?
879 conjunction_to_list_with_rodin_labels(C,L) :- var(C),!,
880 add_error_fail(conjunction_to_list,'Internal error: var :',conjunction_to_list_with_rodin_labels(C,L)).
881 conjunction_to_list_with_rodin_labels(C,List) :-
882 conjunction_to_list_with_labels2(C,List,[]).
883 conjunction_to_list_with_labels2(b(conjunct(A,B),pred,Infos),I,O) :- !,
884 copy_rodin_label(Infos,A,B,LHS,RHS),
885 conjunction_to_list_with_labels2(LHS,I,Inter),
886 conjunction_to_list_with_labels2(RHS,Inter,O).
887 conjunction_to_list_with_labels2(X,I,O) :- X=b(E,_,_),
888 ( E = truth -> I=O
889 ; I = [X|O]).
890
891
892 copy_rodin_label(Infos,A,B,NewA,NewB) :- member(Pos,Infos), is_rodin_label_info(Pos),!,
893 add_rodin_label_info(A,Pos,NewA),
894 add_rodin_label_info(B,Pos,NewB).
895 copy_rodin_label(_,A,B,A,B).
896
897 add_rodin_label_info(b(E,T,I),Pos,b(E,T,I2)) :-
898 (member(Pos,I), is_rodin_label_info(Pos) -> I2=I
899 ; I2 = [Pos|I]).
900
901 is_rodin_label_info(nodeid(Pos)) :- functor(Pos,rodinpos,_).
902
903
904 flatten_conjunctions(List,FlattenedList) :- flatten_conj_aux(List,FlattenedList,[]).
905 flatten_conj_aux([]) --> !, [].
906 flatten_conj_aux([H|T]) --> !, flatten_conj_aux(H),flatten_conj_aux(T).
907 flatten_conj_aux(C) --> {is_a_conjunct(C,LHS,RHS)},
908 !,
909 flatten_conj_aux(LHS), flatten_conj_aux(RHS).
910 flatten_conj_aux(Truth) --> {is_truth(Truth)},!,[].
911 flatten_conj_aux(C) --> [C].
912
913 member_in_conjunction(M,Conj) :- is_a_conjunct(Conj,LHS,RHS),!,
914 ? (member_in_conjunction(M,LHS) ; member_in_conjunction(M,RHS)).
915 member_in_conjunction(M,M).
916
917 % a version of member_in_conjunction which can deal with lazy_let_pred :
918 % member_in_conjunction_cse(FullConjunctWithLets,InnerConjunctNotALet, Conjunction)
919 member_in_conjunction_cse(M,InnerConj,Conj) :- is_a_conjunct(Conj,LHS,RHS),!,
920 (member_in_conjunction_cse(M,InnerConj,LHS) ; member_in_conjunction_cse(M,InnerConj,RHS)).
921 member_in_conjunction_cse(Conj,InnerConj,b(lazy_let_pred(ID,Share,Body),pred,Info)) :-
922 Conj = b(lazy_let_pred(ID,Share,BConj),pred,Info),!,
923 member_in_conjunction_cse(BConj,InnerConj,Body).
924 member_in_conjunction_cse(M,M,M).
925
926 % not terribly efficient way to select and remove a conjunct from a predicate
927 select_member_in_conjunction(M,Conj,Rest) :- is_a_conjunct(Conj,LHS,RHS),!,
928 (select_member_in_conjunction(M,LHS,RL), conjunct_predicates([RL,RHS],Rest)
929 ; select_member_in_conjunction(M,RHS,RR), conjunct_predicates([LHS,RR],Rest)).
930 select_member_in_conjunction(M,M,b(truth,pred,[])).
931
932 is_a_disjunct(b(disjunct(A,B),pred,_),A,B).
933 is_a_negation(b(negation(A),pred,_),A).
934
935 disjunction_to_list(C,L) :- var(C),!,
936 add_error_fail(disjunction_to_list,'Internal error: var :',disjunction_to_list(C,L)).
937 disjunction_to_list(C,List) :-
938 disjunction_to_list2(C,List,[]).
939 disjunction_to_list2(C,I,O) :- is_a_disjunct(C,LHS,RHS),!,
940 disjunction_to_list2(LHS,I,Inter),
941 disjunction_to_list2(RHS,Inter,O).
942 disjunction_to_list2(X,[X|R],R).
943
944 is_an_implication(b(implication(A,B),pred,_),A,B).
945
946 is_an_equivalence(b(equivalence(A,B),pred,_),A,B).
947
948
949 is_a_disjunct_or_implication(b(DI,pred,_),Type,A,B) :- is_a_disj_or_impl_aux(DI,Type,A,B).
950 is_a_disj_or_impl_aux(disjunct(A,B),'disjunction',A,B).
951 is_a_disj_or_impl_aux(implication(A,B),'implication',NA,B) :-
952 create_negation(A,NA).
953 is_a_disj_or_impl_aux(negation(b(conjunct(A,B),pred,_)),'negated conjunction',NA,NB) :-
954 create_negation(A,NA),create_negation(B,NB).
955
956 % a more liberal version of is_a_conjunct/2 which also detects negated disjunctions/implications
957 is_a_conjunct_or_neg_disj(b(DI,pred,I),A,B) :- is_conjunct_aux(DI,I,A,B).
958
959 is_conjunct_aux(conjunct(LHS,RHS),_,LHS,RHS).
960 is_conjunct_aux(negation(DISJ),_,NegLHS,NegRHS) :-
961 is_a_disjunct_or_implication(DISJ,_Type,LHS,RHS),
962 create_negation(LHS,NegLHS),
963 create_negation(RHS,NegRHS).
964 is_conjunct_aux(equal(TA,TB),I,b(equal(TA1,TB1),pred,I),b(equal(TA2,TB2),pred,I)) :-
965 % split TA1|->TA2 = TB1|->TB2, cf, split_equality/3; useful for enumeration order analysis
966 get_texpr_couple(TA,TA1,TA2),
967 get_texpr_couple(TB,TB1,TB2).
968 % print('Splitting equality in is_a_conjunct_or_neg_disj: '), translate:print_bexpr(b(equal(TA,TB),pred,I)),nl.
969
970 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
971 % remove all info fields by fresh variables
972 % typically the result will be unified with AST terms which contain full info fields
973 remove_all_infos(TExpr,TNExpr) :-
974 var(TExpr),!,TExpr=TNExpr.
975 % in contrast to remove_all_infos_and_ground we provide no special treatment of values with closures here;
976 % there could be a problem if we unify with a free variable as value
977 remove_all_infos(TExpr,TNExpr) :-
978 get_texpr_expr(TExpr,Expr),
979 get_texpr_type(TExpr,Type),
980 syntaxtransformation(Expr,Subs,_,NSubs,NExpr),
981 create_texpr(NExpr,Type,_,TNExpr),
982 maplist(remove_all_infos,Subs,NSubs).
983
984 % replace all info fields
985 remove_all_infos_and_ground(TExpr,TNExpr) :-
986 var(TExpr),!,TExpr=TNExpr.
987 remove_all_infos_and_ground(b(value(Value),Type,_),TNExpr) :-
988 % special case for closure(_,_,_) since it is not covered by syntraxtransformation/5
989 % most useful for intervals
990 !,
991 remove_all_infos_from_bvalue(Value,NValue),
992 TNExpr = b(value(NValue),Type,[]).
993 remove_all_infos_and_ground(TExpr,TNExpr) :-
994 get_texpr_expr(TExpr,Expr),
995 get_texpr_type(TExpr,Type),
996 syntaxtransformation(Expr,Subs,_,NSubs,NExpr),
997 create_texpr(NExpr,Type,[],TNExpr),
998 maplist(remove_all_infos_and_ground,Subs,NSubs).
999
1000 remove_all_infos_from_bvalue(Var,Res) :- var(Var),!, Res=Var.
1001 remove_all_infos_from_bvalue((A,B),(RA,RB)) :- !,
1002 remove_all_infos_from_bvalue(A,RA),
1003 remove_all_infos_from_bvalue(B,RB).
1004 remove_all_infos_from_bvalue(closure(P,T,Body),Res) :- !,
1005 remove_all_infos_and_ground(Body,RBody),
1006 Res = closure(P,T,RBody).
1007 % TODO: we could provide more cases like records, sets as lists, freetype values
1008 remove_all_infos_from_bvalue(Val,Val).
1009
1010 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1011
1012 % a version of create_exists_opt which also detects top-level disjunctions
1013 % and marks the exists as generated and as allow_to_lift_exists
1014 create_exists_opt_liftable(Ids,b(disjunct(A,B),pred,Info1),NewPred) :- !,
1015 create_exists_opt_liftable(Ids,A,PA),
1016 create_exists_opt_liftable(Ids,B,PB),
1017 disjunct_predicates_with_pos_info(PA,PB,b(NP,pred,Info2)),
1018 NewPred=b(NP,pred,NewInfo),
1019 extract_just_important_info_aux(Info1,Info2,NewInfo). % copy symbolic or other relevant info
1020 create_exists_opt_liftable(Ids,Pred,NewPred) :- conjunction_to_list(Pred,L),
1021 create_exists_opt(Ids,L,[allow_to_lift_exists],NewPred,_Modified).
1022
1023 % create_exists_opt(TIds,Preds,NewPred)
1024 % creating an existential quantification with some optimisations.
1025 % TIds: The typed identifiers that are quantified
1026 % Preds: A list of predicates
1027 % NewPred: The (optimised) quantified expression
1028 % Basically two optimisations are performed:
1029 % - identifiers that are not used at all are removed from the quantifier
1030 % - predicates that do not use one of the quantified identifiers are moved
1031 % outside the quantification, resulting in a predicate of the form "P & #x.Q(x)"
1032
1033 create_exists_opt(TIds,Preds,NewPred) :-
1034 create_exists_opt(TIds,Preds,[],NewPred,_).
1035
1036 create_exists_opt(TIds,Preds,NewPred,Modified) :-
1037 create_exists_opt(TIds,Preds,[],NewPred,Modified).
1038
1039 create_exists_opt([],Preds,_,NewPred,Modified) :- !, Modified = false,
1040 conjunct_predicates(Preds,NewPred).
1041 create_exists_opt(TIds,Preds,AdditionalInfos,Res,Mod) :-
1042 get_texpr_ids(TIds,UnsortedIds), sort(UnsortedIds,Ids),
1043 (create_exists_opt1(TIds,Ids,Preds,AdditionalInfos,NewPred2,Modified) -> Res = NewPred2, Mod=Modified
1044 ; add_internal_error('Call failed:',create_exists_opt(TIds,Preds,AdditionalInfos,_,_)),fail).
1045 %create_exists_opt1(TIds,_,Preds,AdditionalInfos,NewPred,Modified) :- preference(data_validation_mode,true),
1046 % % do not lift predicates outside of existential quantifiers and change order; see rule_avec_DV.mch ClearSy example (N_ITERa_avec_DV_sans_DV) and test 1945
1047 create_exists_opt1(TIds,Ids,Preds,AdditionalInfos,NewPred2,Modified) :-
1048 create_exists_opt2(Preds,first,Ids,[],Inner,Outer,UsedIds),
1049 % Inner: quantified part, Outer: part which does not have to be quantified
1050 ( Inner = [] -> AllPreds=Outer % no exists needed
1051 ; % Inner = [_|_] ->
1052 create_filtered_exists(TIds,UsedIds,Inner,AdditionalInfos,Exists,IModified),
1053 append(Outer,[Exists],AllPreds)
1054 ),
1055 (Outer=[_|_] -> Modified=true % TO DO: check if TIds=UsedTIds
1056 ; IModified==true -> Modified=true
1057 ; UsedIds == Ids -> Modified= false
1058 ; Modified=true),
1059 conjunct_predicates(AllPreds,NewPred2).
1060
1061 % create an exists for the used Ids only
1062 create_filtered_exists(TIds,UsedIds,Inner,AdditionalInfos,Exists,_) :-
1063 ceo_filter_used_ids(TIds,UsedIds,UsedTIds), % filter out unused variables
1064 conjunct_predicates_with_pos_info(Inner,I), % we could store used_ids info
1065 create_exists_detect_tautology_aux(UsedTIds,I,AdditionalInfos,Exists).
1066 % remove_typing also added in create_exists_detect_tautology_aux
1067
1068
1069 % return Inner: predicates inside quantifier and Outer: predicates that can be moved out of the quantifier
1070 create_exists_opt2([],_,_Ids,UsedIds,[],[],UsedIds) :- !.
1071 create_exists_opt2([Pred|Prest],First,Ids,UsedIdsIn,Inner,Outer,UsedIdsOut) :- !,
1072 find_identifier_uses_if_necessary(Pred, [], LocalUses), % TODO: add used_ids(LocalUses) to Pred
1073 ord_intersection(Ids,LocalUses,ExistsIdsUsed),
1074 ( ExistsIdsUsed = [], % Pred uses none of the quantified ids: we can move it out
1075 (First==first -> true
1076 ; preference(data_validation_mode,false), % see test 1945; step 39 in trace replay
1077 always_well_defined_or_disprover_mode(Pred) % TODO: we should probably also check this !
1078 )
1079 ->
1080 Inner = Irest,
1081 Outer = [Pred|Orest], % move Pred out of existential quantifier as it does not depend on quantified variables
1082 % format('MOVED out of #(~w): ',[Ids]),translate:print_bexpr(Pred), format(' Uses ~w [~w]~n',[LocalUses,ExistsIdsUsed]),
1083 create_exists_opt2(Prest,first,Ids,UsedIdsIn,Irest,Orest,UsedIdsOut)
1084 ;
1085 update_used_ids(Pred,LocalUses,Pred2),
1086 Inner = [Pred2|Irest],
1087 Outer = Orest,
1088 ord_union(UsedIdsIn,ExistsIdsUsed,Urest),
1089 create_exists_opt2(Prest,not_first_anymore,Ids,Urest,Irest,Orest,UsedIdsOut)
1090 ).
1091 create_exists_opt2(Pred,First,Ids,UsedIdsIn,Inner,Outer,UsedIdsOut) :-
1092 add_error(create_exists_opt,'Expecting predicate list: ',Pred),
1093 create_exists_opt2([Pred],First,Ids,UsedIdsIn,Inner,Outer,UsedIdsOut).
1094
1095 % construct exists optimized: keep only used TIds
1096 ceo_filter_used_ids([],_UsedIds,[]).
1097 ceo_filter_used_ids([TId|Irest],UsedIds,Filtered) :-
1098 get_texpr_id(TId,Id),
1099 ( ord_member(Id,UsedIds) -> Filtered = [TId|Frest] % id used: keep it
1100 ; Filtered = Frest),
1101 ceo_filter_used_ids(Irest,UsedIds,Frest).
1102
1103 % a version of create_exists which also detects x=E and x:E, x>E, not(x>E) tautologies
1104 % we could replace this by a more generic prover
1105 create_exists_detect_tautology_aux([TID],b(member(LHS,RHS),pred,_),_,Truth) :-
1106 get_texpr_id(LHS,ID), get_texpr_id(TID,ID),
1107 definitely_not_empty_set(RHS),
1108 always_well_defined_or_disprover_mode(RHS),
1109 !, % replace #x.(x:RHS) by TRUTH
1110 debug_format(19,'Detected tautology exists membership over ~w~n',[ID]),
1111 Truth=b(truth,pred,[]).
1112 create_exists_detect_tautology_aux([TID],b(Pred,_,_),_,Truth) :-
1113 is_comparison(Pred,pos_neg(pos,TID),L,R), get_texpr_id(TID,ID),
1114 ((LHS,RHS)=(L,R) ; (LHS,RHS)=(R,L)),
1115 get_texpr_id(LHS,ID),
1116 \+ occurs_in_expr(ID,RHS),
1117 always_well_defined_or_disprover_mode(RHS),
1118 !, % replace #x.(x COMP E) by TRUTH
1119 debug_format(19,'Detected tautology comparison over ~w~n',[ID]),
1120 Truth=b(truth,pred,[]).
1121 %create_exists_detect_tautology_aux(Ids,b(disjunct(A,B),pred,Info1),AdditionalInfos,NewPred) :- !,
1122 % create_exists(Ids,A,PA), create_exists(Ids,B,PB),
1123 % disjunct_predicates_with_pos_info(PA,PB,b(NP,pred,Info2)),
1124 % NewPred=b(NP,pred,NewInfo),
1125 % extract_just_important_info_aux(Info1,Info2,NewInfo). % copy symbolic or other relevant info
1126 create_exists_detect_tautology_aux(Ids,Pred,AdditionalInfos,NewPred2) :-
1127 create_exists_or_let_predicate(Ids,Pred,NewPred),
1128 add_texpr_infos_if_new(NewPred,[removed_typing|AdditionalInfos],NewPred2).
1129 % removed_typing to avoid spurious exists_body_warning, see test 1681, 625
1130
1131
1132 is_eventb_comprehension_set(b(comprehension_set(TopIds,Body),_,Info),Ids,PRED,EXPR) :-
1133 is_eventb_comprehension_set(TopIds,Body,Info,Ids,PRED,EXPR).
1134 is_eventb_comprehension_set([TID1],Body,Info,Ids,PRED,EXPR) :-
1135 Body = b(exists(Ids,InnerBody),pred,_),
1136 conjunction_to_list(InnerBody,Inner),
1137 append(Inner1,[b(equal(TID2,EXPR),pred,EqInfo)],Inner),
1138 (member(was(event_b_comprehension_set),Info) -> true ;
1139 member(prob_annotation('LAMBDA-EQUALITY'),EqInfo) % relevant for TLA2B
1140 ),
1141 same_id(TID1,TID2,_),
1142 conjunct_predicates(Inner1,PRED),
1143 % we check that TID1 is not being used in P1 and not just rely on was(event_b_comprehension_set)
1144 not_occurs_in_expr(PRED,TID1).
1145
1146 % -------------------
1147
1148 is_equal(b(equal(LHS,RHS),pred,_),A,B) :-
1149 ((A,B)=(LHS,RHS) ; (A,B)=(RHS,LHS)).
1150
1151 :- use_module(typing_tools,[type_has_at_least_two_elements/1]).
1152 is_comparison(greater(A,B),_,A,B).
1153 is_comparison(less(A,B),_,A,B).
1154 is_comparison(greater_equal(A,B),_,A,B).
1155 is_comparison(less_equal(A,B),_,A,B).
1156 is_comparison(equal(A,B),pos_neg(P,TID),A,B) :-
1157 % for neg: we need to make sure there is more than one value in the type (otherwise we cannot make equal false)
1158 % for pos: assuming the RHS expression above is well-defined there must be at least one element; no need to check non_empty_type(Type)
1159 (P=pos -> true ; get_texpr_type(TID,Type),type_has_at_least_two_elements(Type)).
1160 is_comparison(not_equal(A,B),pos_neg(P,TID),A,B) :- % ditto but with pos and neg reversed
1161 (P=neg -> true ; get_texpr_type(TID,Type),type_has_at_least_two_elements(Type)).
1162 is_comparison(negation(b(Comp,pred,_)),PosNeg,A,B) :- negate(PosNeg,P2),
1163 is_comparison(Comp,P2,A,B).
1164 negate(pos_neg(pos,T),pos_neg(neg,T)).
1165 negate(pos_neg(neg,T),pos_neg(pos,T)).
1166
1167
1168
1169 % is true if a predicate Pred can be split into two parts:
1170 % Outer which does not depend on LocalIds (can be lifted out) and Inner which does
1171 detect_global_predicates(LocalIds,Pred,Outer,Inner) :-
1172 get_texpr_ids(LocalIds,UnsortedIds), sort(UnsortedIds,Ids),
1173 conjunction_to_list(Pred,Preds),
1174 split_predicate_local_global(Preds,Ids,OuterL,InnerL),
1175 OuterL \= [],
1176 conjunct_predicates(OuterL,Outer),
1177 conjunct_predicates(InnerL,Inner).
1178 split_predicate_local_global([],_Ids,[],[]).
1179 split_predicate_local_global([P|Ps],Ids,Outer,Inner) :-
1180 (is_local_predicate(Ids,P)
1181 -> Inner = [P|Is], split_predicate_local_global(Ps,Ids,Outer,Is)
1182 ; Outer = [P|Os], split_predicate_local_global(Ps,Ids,Os,Inner)).
1183 is_local_predicate(Ids,Pred) :-
1184 find_identifier_uses_if_necessary(Pred, [], LocalUses),
1185 ord_intersect(Ids,LocalUses).
1186
1187 %:- use_module(b_global_sets,[b_global_set/1]).
1188 definitely_not_empty_set(b(SET,T,_)) :- not_empty_set_aux(SET,T).
1189 not_empty_set_aux(bool_set,_).
1190 not_empty_set_aux(integer_set(_),_).
1191 not_empty_set_aux(float_set,_).
1192 not_empty_set_aux(real_set,_).
1193 not_empty_set_aux(string_set,_).
1194 not_empty_set_aux(set_extension(X),_) :- dif(X,[]).
1195 not_empty_set_aux(sequence_extension(X),_) :- dif(X,[]).
1196 not_empty_set_aux(pow_subset(_),_). % always contains at least the empty set
1197 not_empty_set_aux(fin_subset(_),_). % ditto
1198 not_empty_set_aux(seq(_),_). % ditto
1199 not_empty_set_aux(iseq(_),_). % ditto
1200 not_empty_set_aux(pow1_subset(A),_) :- definitely_not_empty_set(A).
1201 not_empty_set_aux(fin1_subset(A),_) :- definitely_not_empty_set(A).
1202 not_empty_set_aux(seq1(A),_) :- definitely_not_empty_set(A).
1203 not_empty_set_aux(iseq1(A),_) :- definitely_not_empty_set(A).
1204 not_empty_set_aux(cartesian_product(A,B),_) :- definitely_not_empty_set(A), definitely_not_empty_set(B).
1205 not_empty_set_aux(partial_function(_A,_B),_). % always contains at least the empty set
1206 not_empty_set_aux(partial_injection(_A,_B),_). % ditto
1207 not_empty_set_aux(relations(_A,_B),_). % ditto
1208 not_empty_set_aux(total_function(A,B),_) :-
1209 (definitely_not_empty_set(B) -> true
1210 ; definitely_empty_set(A)). % if A is empty, then the set of total functions is {{}}
1211 not_empty_set_aux(union(A,B),_) :- (definitely_not_empty_set(A) -> true ; definitely_not_empty_set(B)).
1212 not_empty_set_aux(overwrite(A,B),_) :- (definitely_not_empty_set(A) -> true ; definitely_not_empty_set(B)).
1213 % TODO: add a few more function rules
1214 not_empty_set_aux(value(S),_) :- not_empty_value(S).
1215 %not_empty_set_aux(identifier(X),set(global(X))) :- bmachine:b_get_machine_set(X). % what if we have a local variable ? ENSURE THAT WE DO NOT ALLOW identifier X to stand for global set X; see ExistentialGlobalSetIDTest in Tester % also: b_global_set not yet computed when ast_cleanup runs on startup !
1216 % TO DO: determine which identifier(X) refer to global set names
1217 not_empty_set_aux(interval(A,B),_) :- get_integer(A,IA), get_integer(B,IB), IA =< IB.
1218
1219 :- use_module(b_global_sets,[b_non_empty_global_set/1]).
1220 :- use_module(kernel_freetypes,[is_non_empty_freetype/1]).
1221 not_empty_value(S) :- var(S),!,fail.
1222 not_empty_value(avl_set(_)).
1223 not_empty_value([_|_]).
1224 not_empty_value(global_set(G)) :- b_non_empty_global_set(G). % always true
1225 not_empty_value(freetype(G)) :- is_non_empty_freetype(G). % always true
1226 not_empty_value(closure(P,T,B)) :-
1227 custom_explicit_sets:is_interval_closure(P,T,B,LOW,UP), integer(LOW),integer(UP), LOW =< UP.
1228 %TODO: more closures; see also definitely_not_empty_finite_value
1229
1230 definitely_empty_set(b(ES,_,_)) :- is_empty_set_aux(ES).
1231 is_empty_set_aux(empty_set).
1232 is_empty_set_aux(empty_sequence).
1233 is_empty_set_aux(domain(D)) :- definitely_empty_set(D).
1234 is_empty_set_aux(range(D)) :- definitely_empty_set(D).
1235 is_empty_set_aux(domain_subtraction(_,Rel)) :- definitely_empty_set(Rel).
1236 is_empty_set_aux(domain_restriction(Dom,Rel)) :- (definitely_empty_set(Dom) -> true ; definitely_empty_set(Rel)).
1237 is_empty_set_aux(range_restriction(Rel,Ran)) :- (definitely_empty_set(Ran) -> true ; definitely_empty_set(Rel)).
1238 is_empty_set_aux(range_subtraction(Rel,_)) :- definitely_empty_set(Rel).
1239 is_empty_set_aux(interval(A,B)) :- get_integer(A,IA), get_integer(B,IB), IA > IB.
1240 is_empty_set_aux(intersection(A,B)) :- (definitely_empty_set(A) -> true ; definitely_empty_set(B)).
1241 is_empty_set_aux(set_subtraction(A,_)) :- definitely_empty_set(A).
1242 is_empty_set_aux(union(A,B)) :- definitely_empty_set(A), definitely_empty_set(B).
1243 is_empty_set_aux(overwrite(A,B)) :- definitely_empty_set(A), definitely_empty_set(B).
1244 is_empty_set_aux(value(V)) :- V==[].
1245
1246
1247 get_integer(b(B,_,_),I) :- get_integer_aux(B,I).
1248 get_integer_aux(integer(I),I).
1249 get_integer_aux(value(V),I) :- get_integer_value(V,I).
1250 get_integer_value(V,I) :- nonvar(V),V=int(I), integer(I).
1251
1252
1253
1254 :- use_module(probsrc(custom_explicit_sets),[avl_is_interval/3]).
1255 get_interval(b(I,set(integer),_),Low,Up) :-
1256 is_interval_aux(I,Low,Up).
1257 is_interval_aux(interval(Low,Up),Low,Up).
1258 is_interval_aux(value(CS),Low,Up) :- nonvar(CS), CS=avl_set(AVL), % occurs in Leftpad_i.imp
1259 Low = b(integer(LI),integer,[]), Up = b(integer(UI),integer,[]),
1260 avl_is_interval(AVL,LI,UI).
1261 is_interval_aux(set_extension(List),Low,Up) :- print(l(List)),nl,
1262 sort(List,SList),
1263 SList = [Low|Rest], get_integer(Low,LI),
1264 last(SList,Up), get_integer(Up,UI),
1265 length(List,Len),
1266 Len is UI-LI+1,
1267 maplist(get_integer,Rest,_).
1268
1269 % a simple let-detection
1270 create_exists_or_let_predicate([H|T],b(conjunct(LHS,RHS),pred,I),NewPred) :- get_texpr_id(H,ID),
1271 ? is_equal(LHS,TID,IDEXPR), % TO DO: should we do a more complicated check here ? exist technique useful for SLOT-24 codespeed test
1272 get_texpr_id(TID,ID), \+ occurs_in_expr(ID,IDEXPR),
1273 maplist(not_occurs_in_expr(IDEXPR),T),
1274 !,
1275 NewPred = b(let_predicate([TID],[IDEXPR],Body),pred,I),
1276 %print('LET: '),translate:print_bexpr(NewPred),nl,
1277 create_exists_or_let_predicate(T,RHS,Body).
1278 create_exists_or_let_predicate(Ids,Pred,NewPred) :- create_exists(Ids,Pred,NewPred).
1279
1280 not_occurs_in_expr(IDEXPR,TID) :- get_texpr_id(TID,ID), \+ occurs_in_expr(ID,IDEXPR).
1281
1282 create_exists([],Pred,NewPred) :- !,Pred=NewPred.
1283 create_exists(Ids,Pred,NewPred) :-
1284 find_identifier_uses_for_quantifier_body(Ids,Pred, Used),
1285 extract_info_wo_used_ids(Pred,NewImportantInfo),
1286 create_texpr(exists(Ids,Pred),pred,[used_ids(Used)|NewImportantInfo],NewPred).
1287
1288 % a version of create_exists which can merge with an already present exists if possible
1289 % possibly more expensive as identfiers used are recomputed for the moment (TODO: reuse used_ids and subtract)
1290 create_or_merge_exists(IDs, Condition, Exists):-
1291 get_texpr_expr(Condition,exists(InnerVars,InnerCond)),!,
1292 % fuse two exists together
1293 append(IDs,InnerVars,Vars),
1294 create_or_merge_exists(Vars,InnerCond,Exists).
1295 create_or_merge_exists(IDs, Condition, Exists):-
1296 create_exists(IDs,Condition,Exists).
1297
1298 % see create_unsimplified_exists
1299 not_generated_exists_paras([b(_,_,Infos)|_]) :- nonmember(generated_exists_parameter,Infos).
1300
1301
1302 create_forall([],Pred,NewPred) :- !,Pred=NewPred.
1303 create_forall(Ids,Pred,NewPred) :-
1304 find_identifier_uses_for_quantifier_body(Ids,Pred, Used),
1305 split_forall_body(Pred,LHS,RHS),
1306 extract_info_wo_used_ids_and_pos(LHS,RHS,NewImportantInfo),
1307 create_texpr(forall(Ids,LHS,RHS),pred,[used_ids(Used)|NewImportantInfo],NewPred).
1308 split_forall_body(b(implication(LHS,RHS),_,_),LHS,RHS) :- !.
1309 split_forall_body(RHS,b(truth,pred,[]),RHS).
1310
1311 create_implication(b(truth,pred,_),P,Res) :- !, Res=P.
1312 create_implication(b(falsity,pred,_),P,Res) :- !, create_negation(P,Res).
1313 create_implication(Lhs,Rhs,b(implication(Lhs,Rhs),pred,NewInfo)) :-
1314 extract_info(Lhs,Rhs,NewInfo).
1315
1316 create_equivalence(Lhs,Rhs, b(equivalence(Lhs,Rhs),pred,NewInfo)) :-
1317 extract_info(Lhs,Rhs,NewInfo).
1318
1319 create_negation(b(P,pred,I),Res) :- create_negation_aux(P,I,R),!,Res=R.
1320 create_negation(Pred,b(negation(Pred),pred,NewInfo)) :-
1321 extract_info(Pred,Infos),
1322 (get_texpr_non_label_posinfo(Pred,Pos) -> NewInfo = [Pos|Infos] ; NewInfo=Infos).
1323
1324 create_negation_aux(truth,I,R) :- !, R=b(falsity,pred,I).
1325 create_negation_aux(falsity,I,R) :- !, R=b(truth,pred,I).
1326 create_negation_aux(negation(Pred),_,R) :- R=Pred. % not(not(P)) = P
1327 %create_negation_aux(equal(A,B),I,R) :- !, R=b(not_equal(A,B),pred,I).
1328 %create_negation_aux(not_equal(A,B),I,R) :- !, R=b(equal(A,B),pred,I).
1329 % we could add some rules about negating member <-> not_member, ... but be careful with effects on is_negation_of
1330
1331 % check if something is the negation of something else (quite stupid at the moment)
1332 % used, e.g., to detect IF-THEN-ELSE constructs in b_ast_cleanup
1333 is_negation_of(P,NP) :-
1334 create_negation(P,NotP), % works both with not(A),A or A,not(A)
1335 same_texpr(NotP,NP).
1336 is_negation_of(b(P,pred,_),b(NP,pred,_)) :- is_negation_aux(P,NP).
1337
1338 is_negation_aux(equal(A,B),NP) :- is_negation_of_equality(NP,A,B).
1339 is_negation_aux(not_equal(A,B),NP) :- is_negation_of_disequality(NP,A,B).
1340 is_negation_aux(subset(XA,SA),not_subset(XB,SB)) :- same_texpr(XA,XB), same_texpr(SA,SB).
1341 is_negation_aux(not_subset(XA,SA),subset(XB,SB)) :- same_texpr(XA,XB), same_texpr(SA,SB).
1342 is_negation_aux(subset_strict(XA,SA),not_subset_strict(XB,SB)) :- same_texpr(XA,XB), same_texpr(SA,SB).
1343 is_negation_aux(not_subset_strict(XA,SA),subset_strict(XB,SB)) :- same_texpr(XA,XB), same_texpr(SA,SB).
1344 is_negation_aux(member(XA,SA),not_member(XB,SB)) :- same_texpr(XA,XB), same_texpr(SA,SB).
1345 is_negation_aux(not_member(XA,SA),member(XB,SB)) :- same_texpr(XA,XB), same_texpr(SA,SB).
1346 is_negation_aux(less(A,B),greater_equal(AA,BB)) :- same_texpr(A,AA), same_texpr(B,BB).
1347 is_negation_aux(less(A,B),less_equal(BB,AA)) :- same_texpr(A,AA), same_texpr(B,BB).
1348 is_negation_aux(less_equal(B,A),less(AA,BB)) :- same_texpr(A,AA), same_texpr(B,BB).
1349 is_negation_aux(less_equal(A,B),greater(AA,BB)) :- same_texpr(A,AA), same_texpr(B,BB).
1350 is_negation_aux(greater_equal(A,B),NP) :- is_negation_aux(less_equal(B,A),NP).
1351 is_negation_aux(greater(A,B),NP) :- is_negation_aux(less(B,A),NP).
1352 is_negation_aux(less_equal_real(B,A),less_real(AA,BB)) :- same_texpr(A,AA), same_texpr(B,BB).
1353 is_negation_aux(less_real(B,A),less_equal_real(AA,BB)) :- same_texpr(A,AA), same_texpr(B,BB).
1354 is_negation_aux(negation(A),negation(B)) :- is_negation_of(A,B).
1355 is_negation_aux(truth,falsity).
1356 is_negation_aux(falsity,truth).
1357 % TO DO: detect more ?? x < y <=> not ( x > y-1 )
1358
1359 is_negation_of_equality(not_equal(AA,BB),A,B) :- same_texpr(A,AA), same_texpr(B,BB).
1360 is_negation_of_equality(equal(AA,BB),A,B) :- same_texpr(A,AA), neg_value(BB,B).
1361
1362 neg_value(b(boolean_true,_,_),b(boolean_false,_,_)).
1363 neg_value(b(boolean_false,_,_),b(boolean_true,_,_)).
1364
1365 is_negation_of_disequality(equal(AA,BB),A,B) :- same_texpr(A,AA), same_texpr(B,BB).
1366 is_negation_of_disequality(not_equal(AA,BB),A,B) :- same_texpr(A,AA), neg_value(BB,B).
1367
1368
1369 % another version which is simpler can can be used to get the negation of some operators
1370
1371 get_negated_operator_expr(b(E,pred,_),Res) :- negate_expr_aux(E,Res).
1372 negate_expr_aux(falsity,truth).
1373 negate_expr_aux(truth,falsity).
1374 negate_expr_aux(member(X,S),not_member(X,S)).
1375 negate_expr_aux(not_member(X,S),member(X,S)).
1376 negate_expr_aux(subset(X,S),not_subset(X,S)).
1377 negate_expr_aux(not_subset(X,S),subset(X,S)).
1378 negate_expr_aux(subset_strict(X,S),not_subset_strict(X,S)).
1379 negate_expr_aux(not_subset_strict(X,S),subset_strict(X,S)).
1380 negate_expr_aux(equal(X,S),not_equal(X,S)).
1381 negate_expr_aux(not_equal(X,S),equal(X,S)).
1382 negate_expr_aux(less(X,S),greater_equal(X,S)).
1383 negate_expr_aux(greater_equal(X,S),less(X,S)).
1384 negate_expr_aux(less_equal(X,S),greater(X,S)).
1385 negate_expr_aux(greater(X,S),less_equal(X,S)).
1386 negate_expr_aux(less_equal_real(X,S),less_real(S,X)).
1387 negate_expr_aux(less_real(X,S),less_equal_real(S,X)).
1388 % TO DO: negation()
1389
1390
1391 % a liberal version for finding equalities
1392 is_equality(TP,TA,TB) :- get_texpr_expr(TP,P), is_equality_aux(P,TA,TB).
1393
1394 is_equality_aux(Var,TA,TB) :- var(Var),!, add_internal_error('Illegal call: ', is_equality_aux(Var,TA,TB)),fail.
1395 is_equality_aux(equal(TA,TB),TA,TB).
1396 is_equality_aux(not_equal(TA,TB),NTA,NTB) :-
1397 (negate_boolean_value(TB,NTB) -> NTA=TA
1398 ; NTB=TB, negate_boolean_value(TA,NTA)). % TA /= TRUE ---> TA = FALSE
1399 is_equality_aux(partition(TA,[TB]),TA,TB).
1400 is_equality_aux(member(TA,TSet),TA,TB) :- singleton_set_extension(TSet,TB). % TA:{TB}
1401 is_equality_aux(negation(TExpr),TA,TB) :- get_negated_operator_expr(TExpr,NT), is_equality_aux(NT,TA,TB).
1402
1403 negate_boolean_value(b(B,T,I),b(NB,T,I)) :- neg_bool_aux(B,NB).
1404 neg_bool_aux(boolean_true,boolean_false).
1405 neg_bool_aux(boolean_false,boolean_true).
1406 % TODO: should we also detect value(pred_true), ....
1407
1408 singleton_set_extension(b(SONE,Type,_),El) :- singleton_set_extension_aux(SONE,Type,El).
1409 singleton_set_extension_aux(set_extension([El]),_,El).
1410 singleton_set_extension_aux(value(Set),set(Type),b(value(El),Type,[])) :- custom_explicit_sets:singleton_set(Set,El).
1411 singleton_set_extension_aux(sequence_extension([El]),_,Couple) :-
1412 ONE = b(integer(1),integer,[]),
1413 create_couple(ONE,El,Couple).
1414
1415
1416 % detect various forms of membership:
1417 is_membership(b(Expr,pred,_),TID,Set) :- is_membership_aux(Expr,TID,Set).
1418 is_membership_aux(member(TID,Set),TID,Set).
1419 is_membership_aux(subset(SONE,Set),TID,Set) :- singleton_set_extension(SONE,TID). % {TID} <: Set
1420
1421 % detect even more forms of membership:
1422 is_membership_or_equality(b(Expr,pred,_),TID,Set) :-
1423 (is_membership_aux(Expr,TID,Set) -> true ; is_mem_eq_aux(Expr,TID,Set)).
1424
1425 is_mem_eq_aux(equal(TID,VAL),TID,Set) :- % x=VAL <==> x:{VAL}
1426 get_texpr_type(VAL,Type),
1427 safe_create_texpr(set_extension([VAL]),set(Type),Set).
1428
1429 % extract a lambda equality from a body; we suppose the equality is the last conjunct
1430 get_lambda_equality(b(equal(TID,ResultExpr),pred,_),ID,[],ResultExpr) :- get_texpr_id(TID,ID).
1431 get_lambda_equality(b(conjunct(LHS,RHS),pred,_),ID,[LHS|T],ResultExpr) :-
1432 get_lambda_equality(RHS,ID,T,ResultExpr).
1433
1434 % ---------------------------------
1435
1436 is_pow_subset(B,Set) :-
1437 ( B = b(pow_subset(Set),_,_)
1438 ; B = b(fin_subset(Set),_,_),
1439 finite_wd_set_value(Set)
1440 ).
1441 is_pow1_subset(B,Set) :-
1442 ( B = b(pow1_subset(Set),_,_)
1443 ; B = b(fin1_subset(Set),_,_),
1444 finite_wd_set_value(Set)
1445 ).
1446
1447 % ---------------------------------
1448
1449 get_texpr_couple(b(couple(TA1,TA2),_,_),TA1,TA2).
1450
1451 % detect TA1|->TA2 = TB1|->TB2 and split into two
1452 split_equality(b(equal(TA,TB),pred,I),b(equal(TA1,TB1),pred,I),b(equal(TA2,TB2),pred,I)) :-
1453 get_texpr_couple(TA,TA1,TA2),
1454 get_texpr_couple(TB,TB1,TB2).
1455
1456 create_equality(b(_,TA,_),b(_,TB,_),_) :- TA \= TB, \+ unify_types_strict(TA,TB),!,
1457 add_internal_error('Creating equality with incompatible types:',equal(TA,TB)),fail.
1458 create_equality(A,B,Equality) :-
1459 safe_create_texpr(equal(A,B),pred,Equality).
1460
1461 create_couple(A,B,b(couple(A,B),couple(TA,TB),Infos)) :-
1462 get_texpr_type(A,TA), get_texpr_type(B,TB),
1463 extract_info(A,B,Infos).
1464
1465 % couplise_list for typed expression list
1466 create_couple([A],Couple) :- !,A=Couple.
1467 create_couple([A,B|Rest],Couple) :-
1468 create_couple(A,B,Couple1),
1469 create_couple([Couple1|Rest],Couple).
1470
1471 create_cartesian_product(A,B,CartAB) :-
1472 get_texpr_types([A,B],[STA,STB]),
1473 is_set_type(STA,TypeA), is_set_type(STB,TypeB),
1474 safe_create_texpr(cartesian_product(A,B),set(couple(TypeA,TypeB)),CartAB).
1475
1476 % derive typing from Ids
1477 create_comprehension_set(Ids,Pred,Info,CompSet) :-
1478 get_texpr_types(Ids,Types),
1479 couplise_list(Types,ElementType),
1480 create_texpr(comprehension_set(Ids,Pred),set(ElementType),Info,CompSet).
1481
1482
1483 :- assert_must_succeed(bsyntaxtree:nested_couple_to_list(b(couple(b(couple(a,b),x,[]),c),xx,[]),[a,b,c])).
1484 :- assert_must_succeed(bsyntaxtree:nested_couple_to_list(b(couple(a,c),x,[]),[a,c])).
1485 :- assert_must_succeed(bsyntaxtree:nested_couple_to_list(b(couple(a,b(couple(b,c),x,[])),xx,[]),[a,b(couple(b,c),x,[])])).
1486 nested_couple_to_list(NC,L) :- nested_couple_to_list_dcg(NC,L,[]).
1487 nested_couple_to_list_dcg(b(couple(A,B),_,_)) --> !,
1488 nested_couple_to_list_dcg(A), [B].
1489 nested_couple_to_list_dcg(E) --> [E].
1490
1491 % --------------------------------------
1492
1493
1494 % check if identifier(s) occur in typed expressions
1495
1496 occurs_in_expr(ID,TExpr) :- var(ID),!,
1497 add_internal_error('Variable id: ',occurs_in_expr(ID,TExpr)),fail.
1498 occurs_in_expr(ID,TExpr) :- ID=b(_,_,_),!, add_internal_error('Non-atomic identifier: ',occurs_in_expr(ID,TExpr)),fail.
1499 occurs_in_expr(ID,TExpr) :- ID=[_|_],!,
1500 add_internal_error('List instead of identifier: ',occurs_in_expr(ID,TExpr)),fail.
1501 occurs_in_expr(ID,TExpr) :- occurs_in_expr1(TExpr,ID).
1502
1503 % treat a few common operators here; possibly avoid traversing whole term if we find ID in a sub-tree
1504 occurs_in_expr1(TExpr,ID) :- TExpr = b(Expr,_,_),!,
1505 occurs_in_expr2(Expr,TExpr,ID).
1506 occurs_in_expr1(TExpr,ID) :- add_internal_error('Illegal typed expression:',occurs_in_expr1(TExpr,ID)).
1507
1508 occurs_in_expr2(add(A,B),_,ID) :- !,
1509 (occurs_in_expr1(A,ID) -> true ; occurs_in_expr1(B,ID)).
1510 occurs_in_expr2(conjunct(A,B),_,ID) :- !,
1511 (occurs_in_expr1(A,ID) -> true ; occurs_in_expr1(B,ID)).
1512 occurs_in_expr2(couple(A,B),_,ID) :- !,
1513 (occurs_in_expr1(A,ID) -> true ; occurs_in_expr1(B,ID)).
1514 occurs_in_expr2(member(A,B),_,ID) :- !,
1515 (occurs_in_expr1(A,ID) -> true ; occurs_in_expr1(B,ID)).
1516 occurs_in_expr2(equal(A,B),_,ID) :- !,
1517 (occurs_in_expr1(A,ID) -> true ; occurs_in_expr1(B,ID)).
1518 occurs_in_expr2(function(A,B),_,ID) :- !,
1519 (occurs_in_expr1(A,ID) -> true ; occurs_in_expr1(B,ID)).
1520 occurs_in_expr2(image(A,B),_,ID) :- !,
1521 (occurs_in_expr1(A,ID) -> true ; occurs_in_expr1(B,ID)).
1522 occurs_in_expr2(intersection(A,B),_,ID) :- !,
1523 (occurs_in_expr1(A,ID) -> true ; occurs_in_expr1(B,ID)).
1524 occurs_in_expr2(interval(A,B),_,ID) :- !,
1525 (occurs_in_expr1(A,ID) -> true ; occurs_in_expr1(B,ID)).
1526 occurs_in_expr2(not_equal(A,B),_,ID) :- !,
1527 (occurs_in_expr1(A,ID) -> true ; occurs_in_expr1(B,ID)).
1528 occurs_in_expr2(assertion_expression(A,_Msg,B),_,ID) :- !,
1529 (occurs_in_expr1(A,ID) -> true ; occurs_in_expr1(B,ID)).
1530 occurs_in_expr2(domain(A),_,ID) :- !, occurs_in_expr1(A,ID).
1531 occurs_in_expr2(range(A),_,ID) :- !, occurs_in_expr1(A,ID).
1532 occurs_in_expr2(record_field(A,_FieldName),_,ID) :- !, occurs_in_expr1(A,ID).
1533 occurs_in_expr2(identifier(ID1),_,ID) :- !,
1534 ID1 = ID.
1535 occurs_in_expr2(integer(_),_,_ID) :- !,fail.
1536 occurs_in_expr2(string(_),_,_ID) :- !,fail.
1537 occurs_in_expr2(value(_),_,_ID) :- !,fail.
1538 occurs_in_expr2(truth,_,_ID) :- !,fail.
1539 occurs_in_expr2(if_then_else(A,B,C),_,ID) :- !,
1540 (occurs_in_expr1(A,ID) -> true ; occurs_in_expr1(B,ID) -> true ; occurs_in_expr1(C,ID)).
1541 occurs_in_expr2(rec(Fields),_,ID) :- !,
1542 l_field_occurs_in_expr1(Fields,ID).
1543 occurs_in_expr2(set_extension(Elements),_,ID) :- !,
1544 l_occurs_in_expr1(Elements,ID).
1545 occurs_in_expr2(sequence_extension(Elements),_,ID) :- !,
1546 l_occurs_in_expr1(Elements,ID).
1547 occurs_in_expr2(Expr,_,ID) :-
1548 syntaxelement(Expr,List,[], [], [], _), % no bound quantifiers; TO DO: treat bound quantifiers
1549 !,
1550 l_occurs_in_expr1(List,ID).
1551 occurs_in_expr2(_E,TExpr,ID) :-
1552 %functor(_E,F,N), print(occurs_in_expr2(F,N,ID)),nl,
1553 (find_identifier_uses_if_necessary(TExpr,[],Used)
1554 -> %check_sorted(Used),
1555 %add_message(bsyntaxtree,'Occurs check: ',ID:Used,TExpr), translate:nested_print_bexpr(TExpr),nl,
1556 ord_member(ID,Used)
1557 ; add_failed_call_error(find_identifier_uses(TExpr,[],_)),fail).
1558 % TO DO: optimize so that we only look for ID; we don't have to keep track of other IDs
1559
1560 l_occurs_in_expr1([H|T],ID) :- !,
1561 (occurs_in_expr1(H,ID) -> true ; l_occurs_in_expr1(T,ID)).
1562 l_occurs_in_expr1(L,ID) :- L \= [],
1563 add_internal_error('Illegal typed expression list:',l_occurs_in_expr1(L,ID)).
1564 l_field_occurs_in_expr1([field(_,H)|T],ID) :- !,
1565 (occurs_in_expr1(H,ID) -> true ; l_field_occurs_in_expr1(T,ID)).
1566 l_field_occurs_in_expr1(L,ID) :- L \= [],
1567 add_internal_error('Illegal record field list:',l_field_occurs_in_expr1(L,ID)).
1568
1569 %check_sorted(List) :- sort(List,SL), (SL \= List -> add_internal_error('Not sorted:',List) ; true).
1570
1571 some_id_occurs_in_expr([H|T],TExpr) :- (var(H) ; \+ atomic(H) ; var(T) ; T=[H2|_], H2 @< H),
1572 add_internal_error('Must be (sorted) atomic identifiers: ',some_id_occurs_in_expr([H|T],TExpr)),
1573 fail.
1574 some_id_occurs_in_expr([Id],TExpr) :- !, % use version without complete find_identifier_uses
1575 occurs_in_expr(Id,TExpr).
1576 some_id_occurs_in_expr(SortedIDs,TExpr) :-
1577 find_identifier_uses_if_necessary(TExpr,[],Used),
1578 list_to_ord_set(Used,UsedSorted),
1579 ord_intersect(UsedSorted,SortedIDs).
1580
1581 % -----------------------------
1582
1583 % find used identifiers in typed expressions
1584
1585 % a special version for quantifier bodies, attempting to reuse used_ids info
1586 find_identifier_uses_for_quantifier_body(TIds,Body,Res) :-
1587 get_texpr_ids(TIds,Ids),
1588 list_to_ord_set(Ids,Ignore),
1589 find_identifier_uses_if_necessary(Body,Ignore,Res).
1590
1591 % only run find_identifier_uses if necessary because no used_ids Info field present
1592 % TO DO: we could consider using used_ids within find_typed_identifier_uses: drawback: we would need to store types
1593 find_identifier_uses_if_necessary(Expr,Ignore,Res) :-
1594 get_texpr_info(Expr,I),
1595 ? member(used_ids(UIds),I),!, %print('+'),nl,
1596 find_with_reuse(Expr,UIds,Ignore,Res).
1597 find_identifier_uses_if_necessary(Expr,Ignore,Res) :- find_identifier_uses(Expr,Ignore,Res).
1598
1599 find_with_reuse(Expr,UIds,Ignore,Res) :- preference(prob_safe_mode,true),
1600 !,
1601 (is_ordset(Ignore) -> true ; add_internal_error('Not ordset: ',Ignore)),
1602 (is_ordset(UIds) -> true ; add_internal_error('Not ordset: ',UIds)),
1603 ord_subtract(UIds,Ignore,Res0),
1604 find_identifier_uses(Expr,Ignore,Res1),
1605 (Res1=Res0 -> true
1606 ; ord_subtract(Res1,Res0,Miss), % missing
1607 ord_subtract(Res0,Res1,Res01), % too much
1608 (Miss=[] -> add_message(find_identifier_uses_if_necessary,'Suboptimal used_ids: ',Res01,Expr)
1609 ; add_internal_error('Incorrect used_ids:',used_ids(missing(Miss),toomuch(Res01),usedids(UIds),
1610 ignore(Ignore),real(Res1))),
1611 translate:print_bexpr(Expr),nl
1612 )
1613 ),
1614 Res=Res1.
1615 find_with_reuse(_,UIds,Ignore,Res) :-
1616 %(is_ordset(Ignore) -> true ; add_internal_error('Not ordset: ',Ignore)),
1617 ord_subtract(UIds,Ignore,Res).
1618
1619
1620 find_identifier_uses_top_level(TExpr,Ids) :-
1621 % get_global_identifiers(Ignored), % ignore all global sets and global constants;
1622 % hence find_identifier_uses_top_level/2 usually should only be called for top level expressions
1623 Ignored = [], % much more efficient to exclude afterwards for long lists of Ignored ids
1624 find_identifier_uses(TExpr,Ignored,Ids0),
1625 exclude_global_identifiers(Ids0,Ids).
1626
1627 :- use_module(tools,[safe_sort/3]).
1628 find_identifier_uses(TExpr,Ignored,Ids) :-
1629 %tools_printing:print_term_summary(find_identifier_uses(TExpr,Ignored,Ids)),nl,
1630 check_is_texpr(TExpr,find_identifier_uses),
1631 (find_typed_identifier_uses(TExpr,Ignored,TIds)
1632 -> get_texpr_ids(TIds,RIds),
1633 % in case of type errors, or when type checking is not yet complete, we can have multiple entries of the same identifier with different types !
1634 sort(RIds,Ids) % was remove_dups, but remove_dups just calls sort; TODO: implement get_sorted_texpr_ids
1635 ; add_internal_error('Call failed:',find_typed_identifier_uses(TExpr,Ignored,_)),
1636 Ids=[]
1637 ).
1638 find_identifier_uses_l(TExprs,Ignored,Ids) :-
1639 find_typed_identifier_uses_l(TExprs,Ignored,TIds),
1640 get_texpr_ids(TIds,RIds),
1641 sort(RIds,Ids). % see above
1642
1643 check_is_texpr(X,Context) :-
1644 (get_texpr_expr(X,_) -> true ; add_internal_error('Expected TExpr: ', check_is_texpr(X,Context))).
1645
1646 find_typed_identifier_uses(TExpr,Ids) :-
1647 % get_global_identifiers(Ignored), % ignore all global sets and global constants; hence find_typed_identifier_uses/2 usually should only be called for top level expressions
1648 Ignored = [],
1649 find_typed_identifier_uses(TExpr,Ignored,Ids0),
1650 exclude_global_identifiers(Ids0,Ids).
1651
1652 find_typed_identifier_uses(TExpr,Ignored,Ids) :- var(TExpr),!,
1653 add_internal_error('Variable typed expression: ', find_typed_identifier_uses(TExpr,Ignored,Ids)),
1654 Ids = [].
1655 find_typed_identifier_uses(TExpr,Ignored,Ids) :-
1656 find_typed_identifier_uses_l([TExpr],Ignored,Ids).
1657
1658 find_typed_identifier_uses2(TExpr,Ignored,Ids,Rest) :-
1659 get_texpr_expr(TExpr,Expr),
1660 safe_syntaxelement_det(Expr,Subs,TNames,_,_), % QSubs=[],
1661 ( uses_an_identifier(Expr,Id,TExpr,Ignored) ->
1662 ( ord_member(Id,Ignored) -> Ids=Rest
1663 ;
1664 get_texpr_type(TExpr,Type),
1665 normalize_type(Type,NType), % replace seq by set;
1666 % warning: when type-check not yet complete we have variables here
1667 create_texpr(identifier(Id),NType,[],TId),
1668 %print(adding(Id,NType,Ignored)),nl,
1669 Ids = [TId|Rest]
1670 )
1671 % ; (Expr = becomes_such(TIds,_)), nl,print(uses_primes(Expr)),nl,fail
1672 ; indirectly_uses_identifiers(Expr,Ignored,IndirectIds) ->
1673 add_typed_ids(IndirectIds,Ids,Rest2),
1674 find_typed_identifier_uses2_l(Subs,Ignored,Rest2,Rest)
1675 ; TNames = [] -> find_typed_identifier_uses2_l(Subs,Ignored,Ids,Rest)
1676 ;
1677 %find_typed_identifier_uses2_l(QSubs,Ignored,Ids,Ids2), % useless here as QSubs=[]
1678 get_texpr_ids(TNames,Names),
1679 list_to_ord_set(Names,SNames), ord_union(SNames,Ignored,Ignored2),
1680 find_typed_identifier_uses2_l(Subs,Ignored2,Ids,Rest)).
1681 find_typed_identifier_uses2_l([],_) --> !, [].
1682 find_typed_identifier_uses2_l([Expr|Rest],Ignored) --> !,
1683 find_typed_identifier_uses2(Expr,Ignored),
1684 find_typed_identifier_uses2_l(Rest,Ignored).
1685 find_typed_identifier_uses2_l(E,Ignored) -->
1686 {add_internal_error('Illegal arguments (not a list):',find_typed_identifier_uses2_l(E,Ignored)),fail}.
1687
1688 %Note: above we do not remap uses of Id$0 to Id in becomes_such;
1689 % this is done in find_read_vars_for_becomes_such in b_read_write_info
1690
1691
1692 uses_an_identifier(Expr,Id) :- uses_an_identifier(Expr,Id,none,[]).
1693
1694 uses_an_identifier(identifier(Id),Id,_,_).
1695 uses_an_identifier(lazy_lookup_pred(Id),Id,_,_).
1696 uses_an_identifier(lazy_lookup_expr(Id),Id,_,_).
1697 uses_an_identifier(value(_),Id,b(_,_,Info),Ignored) :- Ignored \= [],
1698 member(was_identifier(Id),Info),
1699 member('$examine_value_was_identifier_info',Ignored),!.
1700
1701 % uses multiple ids and we also need to inspect subs (operation call arguments)
1702 indirectly_uses_identifiers(operation_call_in_expr(Operation,_),Ignored,IndirectIds) :-
1703 get_texpr_info(Operation,Info),
1704 (memberchk(reads(Vars),Info)
1705 -> (var(Vars) % can happen during initial computation of read_write info for recursive operation calls in expr
1706 -> add_message(bsyntaxtree,'Operation reads info not yet computed (probably recursive call): ',Operation,Info),
1707 fail % Assume this is a direct recursive call which adds no used ids,
1708 % case happens in test 1960 for recursive call to Fact; TODO: more robust solution or disallow recursion
1709 ; true)
1710 ; add_warning(bsyntaxtree,'Operation call contains no read infos:',Operation,Info),fail),
1711 ord_subtract(Vars,Ignored,IndirectIds),
1712 IndirectIds \= [].
1713 %indirectly_uses_identifiers(external_pred_call(FunName,_),Ignored,IndirectIds) :-
1714 % expects_state(FunName), TODO: check for which external functions/predicates we need to add ids
1715
1716
1717 % this is to convert untyped ids in operation call reads infos to typed ids
1718 add_typed_ids([]) --> [].
1719 add_typed_ids([Id|T]) --> {var_cst_type(Id,Type)},!,
1720 {create_texpr(identifier(Id),Type,[],TId)}, [TId], add_typed_ids(T).
1721 add_typed_ids([Id|T]) --> {debug_println(19,ignoring_used_id(Id))}, add_typed_ids(T).
1722
1723 :- use_module(bmachine,[bmachine_is_precompiled/0, b_is_variable/2,b_is_constant/2]).
1724 var_cst_type(Name,Type) :- bmachine_is_precompiled,!,
1725 (b_is_variable(Name,Type) ; b_is_constant(Name,Type)),!.
1726 var_cst_type(_,any). % TODO: provide a better solution; maybe only allow untyped find_identifier_uses ??
1727
1728 % -------------
1729
1730 find_typed_identifier_uses_l(TExprs,Ignored,Ids) :-
1731 check_atomic_ids(Ignored),
1732 list_to_ord_set(Ignored,SIgnored),
1733 find_typed_identifier_uses2_l(TExprs,SIgnored,Unsorted,[]),!,
1734 safe_sort(find_typed_identifier_uses,Unsorted,Ids),
1735 (preference(prob_safe_mode,true) -> check_typed_ids(Ids) ; true).
1736 find_typed_identifier_uses_l(TExprs,Ignored,Ids) :-
1737 add_internal_error('Call failed:',find_typed_identifier_uses_l(TExprs,Ignored,Ids)),
1738 fail.
1739
1740 check_typed_ids([]) :- !.
1741 check_typed_ids([b(identifier(ID),T,_)|Tail]) :- !, check_ids3(Tail,ID,T).
1742 check_typed_ids(Other) :- add_internal_error('Unexpected typed id list:',check_typed_ids(Other)).
1743
1744
1745 check_atomic_ids([]) :- !.
1746 check_atomic_ids([Id|_]) :- atomic(Id),!.
1747 check_atomic_ids(Other) :- add_internal_error('Expected atomic id list:',check_atomic_ids(Other)).
1748
1749
1750 check_ids3([],_,_) :- !.
1751 check_ids3([b(identifier(ID),T,_)|Tail],ID1,T1) :- !,
1752 (ID=ID1 -> add_internal_error('Identifier appears multiple times with types:',id(ID,T1,T)) ; true),
1753 check_ids3(Tail,ID,T).
1754 check_ids3(Other,ID1,T1) :- add_internal_error('Unexpected typed id list:',check_ids3(Other,ID1,T1)).
1755
1756
1757 update_used_ids(b(Pred,T,OInfo),UsedIds,b(Pred,T,[used_ids(UsedIds)|NInfo])) :-
1758 delete(OInfo,used_ids(_),NInfo).
1759
1760 % check if some pre-computed used ids are valid wrt find_typed_identifier_uses
1761 check_computed_used_ids(TExpr,CompUsedIds) :-
1762 find_identifier_uses(TExpr,[],RealUsedIds),
1763 (RealUsedIds=CompUsedIds -> print(ok(CompUsedIds)),nl
1764 ; add_error(range,'Unexpected used ids:',CompUsedIds,TExpr),
1765 format('Real: ~w~nComp: ~w~n',[RealUsedIds,CompUsedIds]),trace
1766 ).
1767
1768 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1769 % break predicate into components with disjunct identifiers
1770 % Pred: a predicate
1771 % Components: a list of terms component/2 where the first argument
1772 % is a predicate, the second is the set of used identifiers
1773 predicate_components(Pred,Res) :- predicate_components_in_scope(Pred,[],Res).
1774 predicate_components_in_scope(Pred,LocalVars,Res) :-
1775 predicate_components_with_restriction(Pred,LocalVars,all,Res).
1776
1777 predicate_components_with_restriction(Pred,LocalVars,RestrictionList,Res) :-
1778 conjunction_to_list(Pred,Preds),
1779 l_predicate_identifiers(Preds,LocalVars,PredIds),
1780 (RestrictionList=all -> R=all ; list_to_ord_set(RestrictionList,R)),
1781 try_find_and_remove_equalities(PredIds,PredIds2),
1782 % print(find_components(R)),nl,nl,
1783 %%(member(pred(P,Ids,X),PredIds2), nl,print(pred(Ids,X)),nl,translate:print_bexpr(P),nl,fail ; true),
1784 find_components(PredIds2,R,Components),
1785 !,
1786 %maplist(print_component,Components),
1787 Components=Res.
1788 predicate_components_with_restriction(Pred,_,_,[component(Pred,[])]) :-
1789 add_internal_error('predicate_components failed: ',predicate_components_with_restriction(Pred,_,_,_)).
1790
1791 % print_component(component(Pred,Ids)) :- format('Component over ~w :~n',[Ids]), translate:print_bexpr(Pred),nl.
1792
1793 % get the list of used identifiers for each predicate
1794 l_predicate_identifiers([],_LocalVars,[]).
1795 l_predicate_identifiers([Pred|PRest],LocalVars,[pred(Pred,Ids,_Selected)|IRest]) :-
1796 predicate_identifiers_in_scope(Pred,LocalVars,Ids), % Do not ignore local variables; used instead of enumerate set elements
1797 l_predicate_identifiers(PRest,LocalVars,IRest).
1798
1799
1800 try_find_and_remove_equalities(PredAndIds,PredAndIds2) :-
1801 preferences:get_preference(partition_predicates_inline_equalities,true),
1802 \+ preferences:get_preference(use_solver_on_load,kodkod),
1803 ? find_and_remove_equalities(PredAndIds,RR),
1804 !, PredAndIds2=RR.
1805 try_find_and_remove_equalities(Ps,Ps).
1806
1807 :- use_module(debug,[debug_println/2]).
1808 % find and apply obvious equalities so that they do not interfere with partitioning into components
1809 % example: c = 1 & f: 1..c --> A & g: 1..c --> B
1810 % TO DO: preprocess and do one pass to detect potential equalities
1811 find_and_remove_equalities([],[]).
1812 find_and_remove_equalities(List,[pred(P,PIds,Sel)|FT]) :-
1813 ? select(pred(P,PIds,Sel),List,Rest),
1814 %PIds = [Id],
1815 identifier_equality(P,Id,Value),
1816 %(value_which_can_be_replaced(Value) -> true ; nl,print('Not replaced: '),translate:print_bexpr(Value),nl,fail),
1817 (get_texpr_id(Value,Id2)
1818 -> Id2 \= Id %,print(inline_id(Id,Id2)),nl
1819 % Note: this inlining does *not* help with partitioning; but does help ProB detect common predicates/expressions
1820 ; PIds=[Id],value_which_can_be_replaced(Value)),
1821 debug_println(9,replace_simple_equality(Id,PIds)),
1822 maplist(apply_to_pred(Id,Value),Rest,RT),
1823 !,
1824 ? find_and_remove_equalities(RT,FT).
1825 % TO DO: detect equalityes x = EXPR, where EXPR does not contain x and where x occurs in no other predicate
1826 % we can then annotate x as not to enumerate
1827 find_and_remove_equalities(R,R).
1828
1829 identifier_equality(b(equal(LHS,RHS),_,_),Id,EqTerm) :-
1830 (get_texpr_id(LHS,Id) -> EqTerm = RHS
1831 ; get_texpr_id(RHS,Id) -> EqTerm = LHS).
1832 % TO DO: should we detect other equalities?
1833
1834 value_which_can_be_replaced(b(E,T,_)) :- value_which_can_be_replaced2(E,T).
1835 %(value_which_can_be_replaced2(E,T) -> true ; print(not_val(E)),nl,fail).
1836 value_which_can_be_replaced2(value(_),_).
1837 value_which_can_be_replaced2(integer(_),_).
1838 %value_which_can_be_replaced2(identifier(I),global(G)) :- b_global_constant(G), id_not_used_anywhere(I).
1839 value_which_can_be_replaced2(integer_set(_),_).
1840 value_which_can_be_replaced2(unary_minus(A),_) :- value_which_can_be_replaced(A).
1841 value_which_can_be_replaced2(add(A,B),_) :- value_which_can_be_replaced(A), value_which_can_be_replaced(B).
1842 % we could compute the value
1843 value_which_can_be_replaced2(minus(A,B),_) :- value_which_can_be_replaced(A), value_which_can_be_replaced(B).
1844 value_which_can_be_replaced2(multiplication(A,B),_) :- value_which_can_be_replaced(A), value_which_can_be_replaced(B).
1845 value_which_can_be_replaced2(div(A,B),_) :-
1846 get_integer(B,IB), IB \= 0,
1847 value_which_can_be_replaced(A).
1848 value_which_can_be_replaced2(floored_div(A,B),T) :- value_which_can_be_replaced2(div(A,B),T).
1849 % should we add: with WD check: division, modulo, .... ? see also simple2 in b_ast_cleanup
1850 value_which_can_be_replaced2(max_int,_).
1851 value_which_can_be_replaced2(min_int,_).
1852 value_which_can_be_replaced2(float_set,_).
1853 value_which_can_be_replaced2(real(_),_).
1854 value_which_can_be_replaced2(real_set,_).
1855 value_which_can_be_replaced2(string(_),_).
1856 value_which_can_be_replaced2(string_set,_).
1857 value_which_can_be_replaced2(boolean_true,_).
1858 value_which_can_be_replaced2(boolean_false,_).
1859 value_which_can_be_replaced2(bool_set,_).
1860 value_which_can_be_replaced2(empty_set,_).
1861 value_which_can_be_replaced2(empty_sequence,_).
1862 value_which_can_be_replaced2(couple(A,B),_) :- value_which_can_be_replaced(A), value_which_can_be_replaced(B).
1863 value_which_can_be_replaced2(interval(A,B),_) :- value_which_can_be_replaced(A), value_which_can_be_replaced(B).
1864 value_which_can_be_replaced2(set_extension(L),_) :- maplist(value_which_can_be_replaced,L).
1865 value_which_can_be_replaced2(sequence_extension(L),_) :- maplist(value_which_can_be_replaced,L).
1866 value_which_can_be_replaced2(cartesian_product(A,B),_) :- % typing equations, like t_float = INTEGER*NATURAL1
1867 simple_value_set(A), simple_value_set(B).
1868 value_which_can_be_replaced2(pow_subset(A),_) :- simple_value_set(A).
1869 %value_which_can_be_replaced2(identifier(_),_). % TO DO: check that this is not the LHS identifier which we replace !!
1870 % identifiers can also be replaced: we check above that the only identifier in the predicate is the equality identifier
1871 % TO DO: enable this but then we need to fix replace_id_by_expr2 to updated the used_ids info ! + we can have scoping issues !?; see test 1358
1872
1873 % TO DO: also allow inlining of prj1/prj2 of simple_value_set:
1874 % not_val(comprehension_set([b(identifier(_zzzz_unary),integer,[generated(first)]),b(identifier(_zzzz_binary),integer,[generated(first)]),b(identifier(_lambda_result_),integer,[lambda_result])],b(equal(b(identifier(_lambda_result_),integer,[lambda_result]),b(identifier(_zzzz_unary),integer,[generated(first)])),pred,[prob_annotation(LAMBDA),lambda_result])))
1875 % not_val(comprehension_set([b(identifier(_zzzz_unary),integer,[generated(second)]),b(identifier(_zzzz_binary),integer,[generated(second)]),b(identifier(_lambda_result_),integer,[lambda_result])],b(equal(b(identifier(_lambda_result_),integer,[lambda_result]),b(identifier(_zzzz_binary),integer,[generated(second)])),pred,[prob_annotation(LAMBDA),lambda_result])))
1876
1877 % TO DO: maybe check if it is an infinite type which cannot be evaluated anyway
1878 simple_value_set(b(E,_,_)) :- simple_value_set2(E).
1879 %simple_value_set2(bool_set). % Warning: we could have a finite construct which gets evaluated multiple times
1880 simple_value_set2(string_set).
1881 simple_value_set2(integer_set(_)).
1882 simple_value_set2(float_set).
1883 simple_value_set2(real_set).
1884 simple_value_set2(cartesian_product(A,B)) :- simple_value_set(A), simple_value_set(B).
1885 simple_value_set2(pow_subset(A)) :- simple_value_set(A).
1886 % POW, records struct(_) set ?
1887
1888 % apply a substiution of ID/Expr on a pred(EXPR,VarList,X) term
1889 % Expr must either be a variable or contain no variables at all
1890 apply_to_pred(ID,Expr,pred(E1,PIds1,X),pred(E2,PIds3,X)) :-
1891 ? (select(ID,PIds1,PIds2)
1892 -> replace_id_by_expr(E1,ID,Expr,E2), %,print(applied(ID)),nl,translate:print_bexpr(E2),nl
1893 % TO DO: replace_id_by_expr does not seem to update used_ids info !! check_used_ids_info fails for test 1358 if we allow identifiers inside Expr
1894 (get_texpr_id(Expr,NewID)
1895 -> ord_add_element(PIds2,NewID,PIds3)
1896 ; PIds3 = PIds2)
1897 %, format('Apply ~w -> ~w : ',[ID,NewID]),translate:print_bexpr(E2),nl
1898 ; E1=E2,PIds1=PIds3).
1899
1900
1901 % project a predicate : keep only those Predicates that are directly or
1902 % indirectly relevant for Ids; FullIds are all identifiers used by ProjectedPredicate
1903 project_predicate_on_identifiers(Pred,Ids,ProjectedPredicate,FullIds, RestList) :-
1904 (debug_mode(on)
1905 -> print('project: '),print_bexpr(Pred),nl, print(' on : '), print(Ids),nl
1906 ; true),
1907 conjunction_to_list(Pred,Preds),
1908 l_predicate_identifiers(Preds,[],PredIds), % TO DO: allow LocalVariables to be passed
1909 % print(predids(PredIds)),nl,
1910 try_find_and_remove_equalities(PredIds,PredIds2),
1911 extract_all_predicates(Ids,all,Ids,PredIds2,ProjectedPredicates, RestList,FullIds),
1912 conjunct_predicates(ProjectedPredicates,ProjectedPredicate),
1913 (debug_mode(on)
1914 -> print('*result: '),print_bexpr(ProjectedPredicate),nl,
1915 print(' on : '), print(FullIds),nl
1916 ; true).
1917
1918 %print_preds([]).
1919 %print_preds([pred(P,_IDs,_)|T]) :- translate:print_bexpr(P), nl, print(' '), print_preds(T).
1920
1921 :- use_module(b_global_sets,[b_get_global_constants/1, b_get_enumerated_set_constants/1,
1922 b_get_global_sets/1, exclude_global_identifiers/2, exclude_global_identifiers/3]).
1923 predicate_identifiers(Pred,Ids) :- predicate_identifiers_in_scope(Pred,[],Ids).
1924 predicate_identifiers_in_scope(Pred,LocalVariables,Ids) :-
1925 %get_global_identifiers(IS),
1926 list_to_ord_set(LocalVariables,LV),
1927 %ord_subtract(IS,LV,Ignore2), % Do not ignore any local variable; it will be used instead of enumerate set element
1928 find_identifier_uses_if_necessary(Pred,[],Ids1), % Ignore enumerated set names
1929 exclude_global_identifiers(Ids1,LV,Ids2),
1930 list_to_ord_set(Ids2,Ids).
1931
1932 % see also b_global_constant_or_set_identifier and exclude_global_identifiers
1933 get_global_identifiers(IDs) :- get_global_identifiers(IDs,all).
1934 % get global set and constant identifiers which you usually want to exclude for find_identifier_uses
1935 get_global_identifiers(IDs,Option) :-
1936 (Option=ignore_promoted_constants
1937 % do not include those constants that have been automatically promoted as enumerated set elements
1938 -> b_get_enumerated_set_constants(EnumeratedSetCsts)
1939 ; b_get_global_constants(EnumeratedSetCsts)
1940 ),
1941 % b_global_sets:b_get_global_enumerated_sets(GSets), % is there a reason to exclude deferred sets ??; cardinality inference,... are all done before partitioning ?
1942 b_get_global_sets(GSets),
1943 append(GSets,EnumeratedSetCsts,GE),
1944 list_to_ord_set(GE,IDs).
1945
1946 % find_components(ListOf_pred, Restrict, Out:ListOfComponents)
1947 % role of Restrict: all if we do normal partition or List of VariableIDs on which we restrict our attention to (for Existential quantifier construction)
1948 find_components([],_,[]).
1949 find_components([pred(P,PIds,true)|PRest],Restrict,[component(Pred,Ids)|CRest]) :-
1950 % find all predicates which are using identifiers occuring in PIds
1951 % (and additionally those which use common identifiers )
1952 ord_restrict(Restrict,PIds,InterIDs),
1953 %format('Treating predicate with ids ~w; restr. intersect = ~w~n',[PIds,InterIDs]),
1954 ( InterIDs =[] ->
1955 % we simply copy this predicate into a single component; not with the scope of Restricted IDs
1956 % print(skip(PIds,P)),nl, %
1957 Pred=P, Ids=PIds, PRest=Rest
1958 ;
1959 extract_all_predicates(InterIDs,Restrict,PIds,PRest,Preds,Rest,Ids),
1960 %length([P|Preds],Len), format('Detected component with ~w conjuncts over ~w~n',[Len,Ids]),
1961 conjunct_predicates_with_pos_info([P|Preds],Pred)
1962 ),
1963 find_components(Rest,Restrict,CRest).
1964 extract_all_predicates([],_,_,Preds,Found,Rest,[]) :- !, % selecting done at end: keep same order of conjuncts
1965 select_predicates(Preds,Found,Rest).
1966 extract_all_predicates(Ids,Restrict,OldIds,Preds,Found,Rest,ResultIds) :-
1967 % search for all predicates that directly use one of the
1968 % identifiers in "Ids"
1969 select_all_using_preds(Preds,Ids,FoundIds),
1970 ord_subtract(FoundIds,OldIds,NewIds),
1971 ord_restrict(Restrict,NewIds,NewIdsToExtract),
1972 ord_union(OldIds,FoundIds,OldIds2),
1973 % now recursively do this which the new identifiers that we have found
1974 extract_all_predicates(NewIdsToExtract,Restrict,OldIds2,Preds,Found,Rest,RestIds),
1975 ord_union([Ids,NewIds,RestIds],ResultIds).
1976
1977 % mark all predicates which intersect with ComponentIds and compute new ids to be added to the component
1978 select_all_using_preds([],_,[]).
1979 select_all_using_preds([pred(_P,PIds,Selected)|PRest],ComponentIds,NewFoundIds) :-
1980 ( (Selected==true ; ord_disjoint(PIds,ComponentIds)) ->
1981 NewFoundIds1 = []
1982 ; % we select the predicate for the component
1983 ord_subtract(PIds,ComponentIds,NewFoundIds1),
1984 Selected=true
1985 ),
1986 select_all_using_preds(PRest,ComponentIds,NewFoundIds2),
1987 ord_union(NewFoundIds1,NewFoundIds2,NewFoundIds).
1988
1989 % ord_intersection with special case for all term
1990 ord_restrict(all,Ids,Res) :- !, Res=Ids.
1991 ord_restrict(Restrict,Ids,Res) :- ord_intersection(Ids,Restrict,Res).
1992
1993 select_predicates(Predicates,FoundPreds,OtherPreds) :-
1994 split_list(is_selected_predicate,Predicates,FoundPredIds,OtherPreds),
1995 maplist(extract_found_predicate,FoundPredIds,FoundPreds).
1996 is_selected_predicate(pred(_P,_PIds,Selected)) :- ground(Selected).
1997 extract_found_predicate(pred(P,_PIds,_Selected),P).
1998
1999 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2000 % replace (simultaneously) multiple identifiers by expressions
2001 % this could be used to replace the predicate replace_id_by_expr by mapping everything in a
2002 % singleton list. however, that would involve list operations instead of unifications
2003 parse_pred(Codes,TExpr) :- %format('Parsing ~s~n',[Codes]),
2004 bmachine:b_parse_machine_predicate_from_codes_open(no_quantifier,Codes,[],[],TExpr).
2005 parse_expr(Codes,TExpr) :- bmachine:b_parse_machine_expression_from_codes(Codes,[],TExpr,_Type,true,_Error).
2006 test_result(1,b(equal(b(comprehension_set([b(identifier(__FRESH____),integer,_)],
2007 b(greater(b(identifier(__FRESH____2),integer,_),b(identifier(x),integer,_)),pred,_)),set(integer),_),
2008 b(empty_set,set(integer),_)),pred,_)).
2009
2010 :- assert_must_succeed((bsyntaxtree:parse_pred("{x|x:INTEGER & x>y}={}",T1), replace_ids_by_exprs(T1,[],[],T1))).
2011 :- assert_must_succeed((bsyntaxtree:parse_pred("{x|x:INTEGER & x>y}={}",T1), bsyntaxtree:parse_expr("100",T2),
2012 replace_ids_by_exprs(T1,[y],[T2],R),bsyntaxtree:parse_pred("{x|x>100}={}",T3),same_texpr(R,T3) )).
2013 :- assert_must_succeed((bsyntaxtree:parse_pred("{x|x:INTEGER & x>y}={}",T1),
2014 replace_ids_by_exprs(T1,[y],[b(identifier(x),integer,[])],R),
2015 bsyntaxtree:test_result(1,R),bsyntaxtree:parse_pred("{x|x:INTEGER & x>x}={}",T3),\+ same_texpr(R,T3) )).
2016 :- assert_must_succeed((bsyntaxtree:parse_pred("{x,y|x:INTEGER & y:INTEGER & x>v & y>w}={}",T1),
2017 replace_ids_by_exprs(T1,[v,w],[b(identifier(w),integer,[]),b(identifier(v),integer,[])],R),
2018 bsyntaxtree:parse_pred("{x,y|x:INTEGER & y:INTEGER & x>w & y>v}={}",T3), same_texpr(R,T3) )).
2019 :- assert_must_succeed((gensym:reset_gensym, bsyntaxtree:parse_pred("{x,y|x:INTEGER & y:INTEGER & x>v & y>w}={}",T1),
2020 replace_ids_by_exprs(T1,[v,w],[b(identifier(w),integer,[]),b(identifier(x),integer,[])],R),
2021 translate:translate_bexpression(R,TR),
2022 TR = '{`__FRESH____1`,y|`__FRESH____1` > w & y > x} = {}')). %'{__FRESH____1,y|(__FRESH____1 : INTEGER & y : INTEGER) & (__FRESH____1 > w & y > x)} = {}' )).
2023
2024 replace_ids_by_exprs(TExpr,[TId],[Inserted],Replaced) :- !, % better, more robust and efficient version
2025 check_ids([TId],[Id]),
2026 replace_id_by_expr(TExpr,Id,Inserted,Replaced).
2027 replace_ids_by_exprs(TExpr,[],[],Replaced) :- !, Replaced=TExpr. % Nothing to do
2028 replace_ids_by_exprs(TExpr,Ids,Exprs,Replaced) :-
2029 check_ids(Ids,Ids2), % convert to atomic identifiers
2030 find_identifier_uses_l(Exprs,[],ExprsUsedIds),
2031 sort(ExprsUsedIds,SExprsUsedIds),
2032 generate_rename_list(Ids2,Exprs,RenameList),
2033 %print(replace(RenameList,SExprsUsedIds)),nl,
2034 replace_ids_by_exprs2(RenameList,SExprsUsedIds,TExpr,Replaced,_). %, nl,print(done),nl.
2035 % a version of replace_ids_by_exprs2 for maplist:
2036 %replace_ids_by_exprs1(RenameList,SExprsUsedIds,TExpr,Replaced) :-
2037 % replace_ids_by_exprs2(RenameList,SExprsUsedIds,TExpr,Replaced,_). %, print('Rep: '), translate:print_bexpr(Replaced),nl.
2038
2039 generate_rename_list([],[],[]).
2040 generate_rename_list([ID1|T],[Expr1|TE],[rename(ID1,Expr1)|RT]) :- generate_rename_list(T,TE,RT).
2041
2042 check_ids([],[]).
2043 check_ids([H|T],[ID|IT]) :- (atomic(H) -> ID=H ; def_get_texpr_id(H,ID)), check_ids(T,IT).
2044 replace_ids_by_exprs2(RenameList,ExprsUsedIds,TExpr,Replaced,WDC) :-
2045 remove_bt(TExpr,Expr,NewExpr,TNewExpr),
2046 ? ( Expr = identifier(Id), member(rename(Id,Inserted),RenameList) ->
2047 Replaced = Inserted,
2048 get_texpr_info(Inserted,Infos),
2049 (memberchk(contains_wd_condition,Infos)
2050 -> WDC = true ; WDC = false) % WDC = true means we have added a wd-condition where previously there was none
2051 ; contains_no_ids(Expr) -> Replaced=TExpr, WDC=false
2052 ;
2053 syntaxtransformation_det(Expr,Subs1,Names,NSubs,NewExpr),
2054 find_variable_clashes(Names,ExprsUsedIds,RenameNames), % check for variable caputure
2055 (RenameNames = []
2056 -> Subs = Subs1 % no variable capture occured
2057 ; %format('*** VARIABLE CAPTURE : ~w~n~n',[RenameNames]),
2058 rename_bt_l(Subs1,RenameNames,Subs) % replace affected names by fresh ids in sub arguments (will also change list of quantified variables itself)
2059 ),
2060 %l_replace_ids_by_exprs2(QSubs,RenameList,ExprsUsedIds,NQSubs,WDC1), % QSubs are like RHS of let expression, where Names are not in scope
2061 remove_hidden_names(Names,RenameList,UpdatedRenameList),
2062 ( UpdatedRenameList = [] -> % all Ids are now hidden for the inner expressions
2063 NSubs=Subs, WDC=false
2064 ;
2065 l_replace_ids_by_exprs2(Subs,UpdatedRenameList,ExprsUsedIds,NSubs,WDC)
2066 ),
2067 TNewExpr = b(E1,T1,Info1),
2068 rename_update_used_ids_info(RenameList,Info1,Info2),
2069 add_wd_if_needed(WDC,b(E1,T1,Info2),Replaced)
2070 ).
2071
2072 contains_no_ids(integer(_)).
2073 contains_no_ids(string(_)).
2074 contains_no_ids(value(_)).
2075
2076
2077 % check if we have to rename any quantified variable to avoid variable capture of RHS of renamings
2078 % example, suppose we rename x/y+1 and we enter {y|y>x} we have to generate {fresh|fresh>y+1} and *not* {y|y>y+1}
2079 find_variable_clashes([],_,[]).
2080 find_variable_clashes([Name|Names],ExprsUsedIds,[rename(ID,FRESHID)|Renaming] ) :-
2081 def_get_texpr_id(Name,ID),
2082 ord_member(ID,ExprsUsedIds), % the quantified name is also introduced by the renaming
2083 !,
2084 gensym('__FRESH__',FRESHID),
2085 find_variable_clashes(Names,ExprsUsedIds,Renaming).
2086 find_variable_clashes([_|Names],ExprsUsedIds,Renaming) :-
2087 find_variable_clashes(Names,ExprsUsedIds,Renaming).
2088
2089
2090 l_replace_ids_by_exprs2([],_,_,[],false).
2091 l_replace_ids_by_exprs2([H|T],UpdatedRenameList,ExprsUsedIds,[IH|IT],WDC) :-
2092 replace_ids_by_exprs2(UpdatedRenameList,ExprsUsedIds,H,IH,WDC1),
2093 l_replace_ids_by_exprs2(T,UpdatedRenameList,ExprsUsedIds,IT,WDC2),
2094 and_wdc(WDC1,WDC2,WDC).
2095
2096 % remove any identifiers that are now "invisible" because they are masked by quantified names
2097 % e.g., when we enter #x.(P) then a renaming of x will be "hidden" inside P
2098 remove_hidden_names([],RenameList,RenameList).
2099 remove_hidden_names([Name|Names],RenameList,NewRenameList) :-
2100 def_get_texpr_id(Name,ID),
2101 delete(RenameList,rename(ID,_),RenameList1),
2102 !, % only one rename should exist
2103 %print(del(ID,RenameList1)),nl,
2104 remove_hidden_names(Names,RenameList1,NewRenameList).
2105
2106 find_rhs_ids(rename(Id,TExpr),rename_ids(Id,InsUsedIds)) :- find_identifier_uses(TExpr,[],InsUsedIds).
2107
2108 % apply a rename list to the used_ids,... information fields
2109 % this is more tricky than applying a single identifier, as we first have to deleted all ids
2110 % and remember which ones were deleted, and only then insert the corresponding ids
2111 % e.g., we could have a RenameList = [rename(p,q),rename(q,p)] ; see test 1776 M1_Internal_v3.mch
2112 rename_update_used_ids_info(RenameList,IIn,IOut) :-
2113 l_find_rhs_ids(RenameList,RenameList2),
2114 %maplist(apply_rename_list(RenameList2),IIn,IOut).
2115 l_apply_rename_list(IIn,RenameList2,IOut).
2116
2117 l_find_rhs_ids([],[]).
2118 l_find_rhs_ids([R1|T],[NR1|NTR]) :-
2119 find_rhs_ids(R1,NR1),
2120 l_find_rhs_ids(T,NTR).
2121
2122 l_apply_rename_list([],_,[]).
2123 l_apply_rename_list([Info1|T],RenameList2,[NewInfo1|NTI]) :-
2124 apply_rename_list(RenameList2,Info1,NewInfo1),
2125 l_apply_rename_list(T,RenameList2,NTI).
2126
2127 apply_rename_list(RenameList,I,NI) :-
2128 apply_rename_list2(I,RenameList,NI).
2129 apply_rename_list2(used_ids(IDS),RenameList,used_ids(NewIDS)) :- !, apply_rename_list_to_ids(RenameList,IDS,[],NewIDS).
2130 apply_rename_list2(reads(IDS),RenameList,reads(NewIDS)) :- !, apply_rename_list_to_ids(RenameList,IDS,[],NewIDS).
2131 apply_rename_list2(modifies(IDS),RenameList,modifies(NewIDS)) :- !, apply_rename_list_to_ids(RenameList,IDS,[],NewIDS).
2132 apply_rename_list2(Info,_,Info).
2133
2134 % apply a rename list to a sorted list of ids
2135 apply_rename_list_to_ids([],Acc,ToInsert,Res) :- ord_union(Acc,ToInsert,Res).
2136 apply_rename_list_to_ids([rename_ids(Id,NewIds)|T],Acc,ToInsert,Res) :-
2137 (ord_delete_existing_element(Acc,Id,Acc2) % the Id occurs and is deleted
2138 -> ord_union(NewIds,ToInsert,ToInsert2),
2139 apply_rename_list_to_ids(T,Acc2,ToInsert2,Res)
2140 ; apply_rename_list_to_ids(T,Acc,ToInsert,Res)).
2141
2142 ord_delete_existing_element(List,El,ResList) :- % ord_del_element also succeeds if El is not in the list !
2143 ord_intersection([El],List,[El],ResList).
2144 % -----------------------
2145 % remove an Identifier from used_ids Info field if it exists
2146 remove_used_id_from_info(I,ID_to_remove,NI) :-
2147 update_used_ids_info(I,ID_to_remove,[],NI).
2148
2149 remove_used_ids_from_info([],I,I).
2150 remove_used_ids_from_info([ID_to_remove|T],I,NI) :- remove_used_id_from_info(I,ID_to_remove,I2),
2151 remove_used_ids_from_info(T,I2,NI).
2152
2153 % remove a single Identifier from used_ids Info field if it exists and insert sorted list of ids instead
2154 % a simpler version of rename_update_used_ids_info for a single identifier
2155 update_used_ids_info([],_,_,[]).
2156 update_used_ids_info([InfoField|T],ID_to_remove,IDsInserted,[NewInfoField|NT]) :-
2157 (update_id_from_info_field(ID_to_remove,IDsInserted,InfoField,R)
2158 -> NewInfoField=R
2159 ; NewInfoField=InfoField),
2160 update_used_ids_info(T,ID_to_remove,IDsInserted,NT).
2161
2162 update_id_from_info_field(ID_to_remove,IDsInserted,I,NI) :-
2163 update_id_from_info_field2(I,ID_to_remove,IDsInserted,NI).
2164 update_id_from_info_field2(used_ids(IDS),ID,IDsInserted,used_ids(NewIDS)) :- update_id(IDS,ID,IDsInserted,NewIDS).
2165 update_id_from_info_field2(reads(IDS),ID,IDsInserted,reads(NewIDS)) :- update_id(IDS,ID,IDsInserted,NewIDS).
2166 update_id_from_info_field2(modifies(IDS),ID,IDsInserted,modifies(NewIDS)) :- update_id(IDS,ID,IDsInserted,NewIDS).
2167
2168 update_id(IDS,ID_to_remove,IDsInserted,NewIDS) :-
2169 ord_delete_existing_element(IDS,ID_to_remove,IDS2), % the Id occurs and is deleted
2170 ord_union(IDsInserted,IDS2,NewIDS).
2171 %if ord_del_element fails we do not add IDsInserted: we assume the used_ids info is correct and ID_to_remove does not occur !
2172 % We could use this info to avoid traversing subtree !
2173 % print(projecting_away_unknown_id(ID_to_remove,IDS)),nl,
2174
2175 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2176
2177 :- assert_must_succeed((gensym:reset_gensym, bsyntaxtree:exists_ast(A), replace_id_by_expr(A,y,b(identifier(x),integer,[]),RA),translate:translate_bexpression(RA,TR),
2178 TR = 'r = {`__FRESH____1`|`__FRESH____1` : 1 .. x & `__FRESH____1` mod 2 = 1}' )).
2179 :- assert_must_succeed((bsyntaxtree:parse_pred("{x|x:INTEGER & x>y}={}",T1),
2180 replace_id_by_expr(T1,y,b(identifier(x),integer,[]),R),
2181 bsyntaxtree:test_result(1,R),bsyntaxtree:parse_pred("{x|x:INTEGER & x>x}={}",T3),
2182 \+ same_texpr(R,T3) )).
2183 :- assert_must_succeed((bsyntaxtree:parse_pred("{x|x:INTEGER & x>y}={}",T1), bsyntaxtree:parse_expr("100",T2),
2184 replace_id_by_expr(T1,y,T2,R),bsyntaxtree:parse_pred("{x|x>100}={}",T3),same_texpr(R,T3) )).
2185
2186 % replace an identifier Id by an expression Inserted
2187 replace_id_by_expr(TExpr,Id,Inserted,Replaced) :-
2188 replace_id_by_expr_with_count(TExpr,Id,Inserted,Replaced,_).
2189
2190 replace_id_by_expr_with_count(TExpr,Id,Inserted,Replaced,NrReplacements) :- \+ atomic(Id),!,
2191 add_internal_error('Id not atomic: ',replace_id_by_expr(TExpr,Id,Inserted,Replaced)),
2192 Replaced = TExpr, NrReplacements=0.
2193 replace_id_by_expr_with_count(TExpr,Id,Inserted,Replaced,NrReplacements) :-
2194 %find_all_relevant_quantified_vars(Id,TExpr,QVars),
2195 find_identifier_uses(Inserted,[],SInsUsedIds), % SInsUsedIds is sorted
2196 replace_id_by_expr2(Id,Inserted,SInsUsedIds,TExpr,Replaced,_WDC,0,NrReplacements).
2197
2198 replace_id_by_expr2(Id,Inserted,InsUsedIds,TExpr,Replaced,WDC,InR,OutR) :-
2199 remove_bt(TExpr,Expr,NewExpr,TNewExpr),
2200 ( Expr = identifier(Id) -> % TODO: count number of replacements
2201 Replaced = Inserted,
2202 OutR is InR+1,
2203 get_texpr_info(Inserted,Infos),
2204 (memberchk(contains_wd_condition,Infos)
2205 -> WDC = true ; WDC = false) % WDC = true means we have added a wd-condition where previously there was none
2206 ; contains_no_ids(Expr) -> Replaced=TExpr, WDC=false, OutR=InR
2207 ;
2208 syntaxtransformation_det(Expr,Subs,Names,NSubs,NewExpr),
2209 get_texpr_id(TId,Id),
2210 ( memberchk(TId,Names) -> % the Id is now hidden for the inner expressions
2211 NSubs=Subs, WDC=false, OutR = InR
2212 ; (InsUsedIds \= [],
2213 get_texpr_ids(Names,Ns),sort(Ns,SNs),
2214 ord_intersection(SNs,InsUsedIds,Captured),
2215 Captured \= [] %, print(inter(SNs,InsUsedIds,Captured)),nl
2216 )
2217 % The Names introduced clash with variables used in the Inserted expression
2218 -> findall(rename(X,FRESHID),(member(X,Captured),gensym:gensym('__FRESH__',FRESHID)),RenameList),
2219 %print(rename(RenameList)),nl,
2220 rename_bt_l(Subs,RenameList,RenSubs),
2221 l_replace_id_by_expr2(RenSubs,Id,Inserted,InsUsedIds,NSubs,WDC,InR,OutR)
2222 ;
2223 l_replace_id_by_expr2(Subs,Id,Inserted,InsUsedIds,NSubs,WDC,InR,OutR)
2224 ),
2225 TNewExpr = b(E1,T1,Info1),
2226 update_used_ids_info(Info1,Id,InsUsedIds,Info2),
2227 %(E1 = exists(P,_) -> print(exists(P,Id,Info1,Info2)),nl ; true),
2228 add_wd_if_needed(WDC,b(E1,T1,Info2),Replaced)
2229 ).
2230
2231 l_replace_id_by_expr2([],_,_,_,[],false,R,R).
2232 l_replace_id_by_expr2([H|T],Id,Inserted,InsUsedIds,[IH|IT],WDC,InR,OutR) :-
2233 replace_id_by_expr2(Id,Inserted,InsUsedIds,H,IH,WDC1,InR,InR2),
2234 l_replace_id_by_expr2(T,Id,Inserted,InsUsedIds,IT,WDC2,InR2,OutR),
2235 and_wdc(WDC1,WDC2,WDC).
2236
2237 % conjunct wd condition added flag
2238 and_wdc(true,_,R) :- !,R=true.
2239 and_wdc(_,true,R) :- !, R=true.
2240 and_wdc(_,_,false).
2241
2242 % add contains_wd_condition if a change occured during replacement of id by expression
2243 add_wd_if_needed(true,b(E,T,Infos),Replaced) :-
2244 nonmember(contains_wd_condition,Infos),
2245 !,
2246 Replaced = b(E,T,[contains_wd_condition|Infos]).
2247 add_wd_if_needed(_,T,T).
2248
2249
2250
2251 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2252
2253
2254 % syntaxtransformation_fixed/7 is the same as syntaxtransformation/5 with the exception
2255 % that we distinguish between subexpressions that have the newly introduced identifiers (Names)
2256 % in scope (OSubs) and those who don't (OExprs). The only expressions where the latter case is relevant
2257 % are let_expression and let_predicate.
2258 % TODO: This is a quick'n dirty fix for only some cases.
2259 % NO LONGER REQUIRED: let_expression and let_predicate now obey another semantic, not the Z semantics anymore
2260 %syntaxtransformation_fixed(OExpr,OExprs,OSubs,Names,NExprs,NSubs,NExpr) :-
2261 %syntaxtransformation_fixed(Expr,[],Subs,Names,[],NSubs,NExpr) :-
2262 % syntaxtransformation_det(Expr,Subs,Names,NSubs,NExpr).
2263
2264
2265 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2266 % rename identifier
2267
2268 % r = {x|x : 1..y & x mod 2 = 1}
2269 exists_ast(AST) :- AST =
2270 b(equal(b(identifier(r),set(integer),[nodeid(none)]),
2271 b(comprehension_set([b(identifier(x),integer,[nodeid(none)])],
2272 b(conjunct(b(member(b(identifier(x),integer,[nodeid(none)]),
2273 b(interval(b(integer(1),integer,[nodeid(none)]),b(identifier(y),integer,[nodeid(none)])),
2274 set(integer),[nodeid(none)])),pred,[nodeid(none)]),
2275 b(equal(b(modulo(b(identifier(x),integer,[nodeid(none)]),
2276 b(integer(2),integer,[nodeid(none)])),integer,[contains_wd_condition,nodeid(none)]),
2277 b(integer(1),integer,[nodeid(none)])),pred,
2278 [contains_wd_condition,nodeid(none)])),pred,[contains_wd_condition,nodeid(none)])),
2279 set(integer),[contains_wd_condition,nodeid(none)])),
2280 pred,[contains_wd_condition,nodeid(none)]).
2281
2282 :- assert_must_succeed((bsyntaxtree:exists_ast(A), rename_bt(A,[rename(x,xx)],RA), RA==A )).
2283 :- assert_must_succeed((bsyntaxtree:exists_ast(A), rename_bt(A,[rename(r,v)],RA),
2284 translate:translate_bexpression(RA,TR), TR='v = {x|x : 1 .. y & x mod 2 = 1}' )).
2285 :- assert_must_succeed((gensym:reset_gensym, bsyntaxtree:exists_ast(A), rename_bt(A,[rename(y,x)],RA), RA \= A,
2286 translate:translate_bexpression(RA,TR),
2287 TR = 'r = {`__FRESH____1`|`__FRESH____1` : 1 .. x & `__FRESH____1` mod 2 = 1}' )).
2288
2289 % a simplified version of replace_ids_by_exprs, which assumes target of renamings are variables
2290 rename_bt(Expr,[],Res) :- !,Res=Expr.
2291 rename_bt(OExpr,Renamings,NExpr) :-
2292 create_texpr(Old,Type,OInfo,OExpr),
2293 create_texpr(New,Type,NInfo,NExpr),
2294 rename_in_infos(OInfo,Renamings,NInfo),
2295 rename_bt2(Old,Renamings,New).
2296 rename_bt2(identifier(Old),Renamings,identifier(New)) :-
2297 !, rename_id(Old,Renamings,New).
2298 rename_bt2(lazy_lookup_expr(Old),Renamings,lazy_lookup_expr(New)) :-
2299 !, rename_id(Old,Renamings,New).
2300 rename_bt2(lazy_lookup_pred(Old),Renamings,lazy_lookup_pred(New)) :-
2301 !, rename_id(Old,Renamings,New).
2302 rename_bt2(OExpr,Renamings,NExpr) :-
2303 syntaxtransformation_for_renaming(OExpr,Subs,TNames,NSubs,NExpr),
2304 get_texpr_exprs(TNames,Names),
2305 remove_renamings(Names,Renamings,NRenamings),
2306 rename_bt_l(Subs,NRenamings,NSubs).
2307 rename_bt_l([],_,[]).
2308 rename_bt_l([Old|ORest],Renamings,[New|NRest]) :-
2309 rename_bt(Old,Renamings,New),
2310 rename_bt_l(ORest,Renamings,NRest).
2311
2312 % syntaxtransformation rule for operation_call_in_expr does not show Id field in sub expressions
2313 % (to avoid issues with find_identifier_uses, see below)
2314 % so here we explicitly also rename the operation name if required, relevant for bmachine_construction, test 2504
2315 % TODO: avoid this special case and fix find_identifier_uses instead
2316 syntaxtransformation_for_renaming(operation_call_in_expr(ID,Subs1),Subs,TNames,NSubs,NExpr) :- !,
2317 NExpr = operation_call_in_expr(NID,NSubs1),
2318 Subs = [ID|Subs1],
2319 NSubs = [NID|NSubs1], TNames = [].
2320 syntaxtransformation_for_renaming(OExpr,Subs,TNames,NSubs,NExpr) :-
2321 syntaxtransformation(OExpr,Subs,TNames,NSubs,NExpr).
2322
2323 remove_renamings([],Renamings,Renamings).
2324 remove_renamings([identifier(Name)|Rest],Old,New) :-
2325 ? ( select(rename(Name,_),Old,Inter1) -> true % Name no longer visible to renaming
2326 ; Old = Inter1),
2327 (member(rename(_OldName,Name),Inter1) ->
2328 gensym('__FRESH__',FRESHID),
2329 %print(variable_capture_in_rename(Name,from(OldName),FRESHID)),nl,
2330 Inter2 = [rename(Name,FRESHID)|Inter1]
2331 ; Inter2 = Inter1),
2332 remove_renamings(Rest,Inter2,New).
2333
2334 rename_in_infos(Old,Renamings,New) :-
2335 ( has_info_to_rename(Old) ->
2336 maplist(rename_in_infos2(Renamings),Old,New)
2337 ;
2338 Old = New).
2339 rename_in_infos2(Renamings,OInfo,NInfo) :-
2340 ( infos_to_rename(OInfo,OIds,SortedNIds,NInfo) ->
2341 rename_ids(OIds,Renamings,NIds),
2342 sort(NIds,SortedNIds)
2343 ;
2344 OInfo = NInfo).
2345
2346 rename_ids([],_,[]).
2347 rename_ids([OId|Orest],Renamings,[NId|Nrest]) :-
2348 rename_id(OId,Renamings,NId),
2349 rename_ids(Orest,Renamings,Nrest).
2350 rename_id(Old,Renamings,New) :-
2351 ( memberchk(rename(Old,New),Renamings) -> true % we could use ord_member if we sort !
2352 ; Old=New).
2353
2354 has_info_to_rename(Infos) :-
2355 ? member(I,Infos),infos_to_rename(I,_,_,_),!.
2356
2357 infos_to_rename(modifies(O),O,N,modifies(N)).
2358 infos_to_rename(reads(O),O,N,reads(N)).
2359 infos_to_rename(non_det_modifies(O),O,N,non_det_modifies(N)).
2360 infos_to_rename(modifies_locals(O),O,N,modifies_locals(N)).
2361 infos_to_rename(reads_locals(O),O,N,reads_locals(N)).
2362 infos_to_rename(used_ids(O),O,N,used_ids(N)).
2363 %infos_to_rename(lambda_result(O),[O],[N],lambda_result(N)). % whould we no longer assume that we have lambda result, as predicate has possibly changed!?
2364
2365
2366 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2367 % remove type information for transformations
2368
2369 remove_bt(b(Expr,Type,Infos),Expr,NExpr,b(NExpr,Type,Infos)).
2370
2371 remove_bt_and_used_ids(b(OldExpr,T,Infos),OldExpr,NewExpr,b(NewExpr,T,NewInfos)) :-
2372 delete(Infos,used_ids(_),NewInfos). % invalidate used_ids info
2373
2374 %remove_bt_l([],[],[],[]).
2375 %remove_bt_l([OT|OTRest],[O|ORest],[N|NRest],[NT|NTRest]) :-
2376 % remove_bt(OT,O,N,NT),
2377 % remove_bt_l(OTRest,ORest,NRest,NTRest).
2378
2379 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2380 % traversations
2381 % Takes a predicate or expression or substitution and extracts:
2382 % the expression itself Expr, its type Type, the syntaxnode information Infos
2383 % + the subexpressions as a list Subs and the local identifiers declared
2384 syntaxtraversion(b(Expr,Type,Infos),Expr,Type,Infos,Subs,Names) :- !,
2385 safe_syntaxelement(Expr,Subs,Names,_,_).
2386 syntaxtraversion(IExpr,Expr,Type,Infos,Subs,Names) :-
2387 add_internal_error('Not properly wrapped', syntaxtraversion(IExpr,Expr,Type,Infos,Subs,Names)),
2388 fail.
2389
2390
2391 map_over_full_bexpr_no_fail(P,BExpr) :-
2392 syntaxtraversion(BExpr,Expr,_,_,Subs,_TNames),
2393 call(P,Expr), % the predicate should not fail
2394 (Subs=[] -> true ; maplist(map_over_full_bexpr_no_fail(P),Subs)).
2395
2396 map_over_bexpr(P,BExpr) :-
2397 syntaxtraversion(BExpr,Expr,_,_,Subs,_TNames),
2398 (call(P,Expr) % should probably fail so that by backtrack we recurse
2399 ;
2400 member(Sub,Subs), map_over_bexpr(P,Sub)
2401 ).
2402 % same as above but gets typed expressions:
2403 map_over_typed_bexpr(P,BExpr) :-
2404 syntaxtraversion(BExpr,_Expr,_,_,Subs,_TNames),
2405 (call(P,BExpr)
2406 ;
2407 ? member(Sub,Subs), map_over_typed_bexpr(P,Sub)
2408 ).
2409 % same as above but returns value:
2410 map_over_typed_bexpr(P,BExpr,Result) :-
2411 syntaxtraversion(BExpr,_Expr,_,_,Subs,_TNames),
2412 (call(P,BExpr,Result)
2413 ;
2414 ? member(Sub,Subs), map_over_typed_bexpr(P,Sub,Result)
2415 ).
2416 % this one gets TNames (locally introduced variables as parameter)
2417 map_over_typed_bexpr_with_names(P,BExpr) :-
2418 syntaxtraversion(BExpr,_Expr,_,_,Subs,TNames),
2419 (call(P,BExpr,TNames)
2420 ;
2421 member(Sub,Subs), map_over_typed_bexpr_with_names(P,Sub)
2422 ).
2423
2424 % same as map_over_expr but provides an accumulator passed top-down to children; needs to be used by failure driven loop
2425
2426 map_over_bexpr_top_down_acc(P,BExpr,TDAcc) :-
2427 syntaxtraversion(BExpr,Expr,_,_,Subs,_TNames),
2428 (call(P,Expr,TDAcc,NewAcc)
2429 -> member(Sub,Subs), map_over_bexpr_top_down_acc(P,Sub,NewAcc)
2430 ; member(Sub,Subs), map_over_bexpr_top_down_acc(P,Sub,TDAcc)
2431 ).
2432 % now a version which gets the typed predicate as argument
2433
2434 map_over_typed_bexpr_top_down_acc(P,BExpr,TDAcc) :-
2435 syntaxtraversion(BExpr,_Expr,_,_,Subs,_TNames),
2436 (call(P,BExpr,TDAcc,NewAcc)
2437 -> member(Sub,Subs), map_over_typed_bexpr_top_down_acc(P,Sub,NewAcc)
2438 ; member(Sub,Subs), map_over_typed_bexpr_top_down_acc(P,Sub,TDAcc)
2439 ).
2440
2441 % predicate P has 3 arguments: (Expr,ValueSoFar,NewValue)
2442 reduce_over_bexpr(P,BExpr,InitialValue,ResultValue) :-
2443 syntaxtraversion(BExpr,Expr,_,_,Subs,_TNames),
2444 call(P,Expr,InitialValue,I1), % print(reduce(P,Expr,InitialValue,I1)),nl,
2445 scanlist(reduce_over_bexpr(P),Subs,I1,ResultValue).
2446
2447 % apply a predicate over a syntax tree (bottom-up)
2448
2449 transform_bexpr(Pred,b(Expr,Type,Info),NewBExpr) :- !,
2450 syntaxtransformation(Expr,Subs,_Names,NSubs,NewExpr1),
2451 l_transform_bexpr(Subs,Pred,NSubs),
2452 (call(Pred,b(NewExpr1,Type,Info),NewBExpr) -> true ; NewBExpr = b(NewExpr1,Type,Info)).
2453 transform_bexpr(Pred,Expr,NewBExpr) :-
2454 add_internal_error('Expression not properly wrapped:',transform_bexpr(Pred,Expr,NewBExpr)),
2455 fail.
2456
2457 l_transform_bexpr([],_,[]).
2458 l_transform_bexpr([SubH|T],Pred,[TSubH|TT]) :-
2459 transform_bexpr(Pred,SubH,TSubH),
2460 l_transform_bexpr(T,Pred,TT).
2461
2462 % apply a predicate over a syntax tree (bottom-up), and provide scoping info about local ids
2463
2464 transform_bexpr_with_scoping(Pred,BExpr,NewBExpr) :-
2465 transform_bexpr_with_scoping2(Pred,BExpr,NewBExpr,[]).
2466 transform_bexpr_with_scoping2(Pred,b(Expr,Type,Info),NewBExpr,LocalIds) :-
2467 syntaxtransformation(Expr,Subs,Names,NSubs,NewExpr1),
2468 get_texpr_ids(Names,QuantifiedNewIds), list_to_ord_set(QuantifiedNewIds,SQuantifiedNewIds),
2469 ord_union(LocalIds,SQuantifiedNewIds,NewLocalIds),
2470 l_transform_bexpr_with_scoping(Subs,Pred,NSubs,NewLocalIds),
2471 (call(Pred,b(NewExpr1,Type,Info),NewBExpr,LocalIds) -> true ; NewBExpr = b(NewExpr1,Type,Info)).
2472
2473 l_transform_bexpr_with_scoping([],_,[],_).
2474 l_transform_bexpr_with_scoping([SubH|T],Pred,[TSubH|TT],LocalIds) :-
2475 transform_bexpr_with_scoping2(Pred,SubH,TSubH,LocalIds),
2476 l_transform_bexpr_with_scoping(T,Pred,TT,LocalIds).
2477
2478 % transform a predicate top-down with scoping infos
2479 % if Pred succeeds the top-down traversal stops
2480 transform_bexpr_td_with_scoping(Pred,BExpr,NewBExpr) :-
2481 transform_bexpr_td_with_scoping2(Pred,BExpr,NewBExpr,[]).
2482 transform_bexpr_td_with_scoping2(Pred,b(Expr,Type,Info),b(NewExpr1,Type,Info),LocalIds) :-
2483 ? (call(Pred,Expr,NewExpr1,LocalIds)
2484 -> true
2485 ; syntaxtransformation(Expr,Subs,Names,NSubs,NewExpr1),
2486 get_texpr_ids(Names,QuantifiedNewIds), list_to_ord_set(QuantifiedNewIds,SQuantifiedNewIds),
2487 ord_union(LocalIds,SQuantifiedNewIds,NewLocalIds),
2488 l_transform_bexpr_td_with_scoping(Subs,Pred,NSubs,NewLocalIds)
2489 ).
2490
2491 l_transform_bexpr_td_with_scoping([],_,[],_).
2492 l_transform_bexpr_td_with_scoping([SubH|T],Pred,[TSubH|TT],LocalIds) :-
2493 transform_bexpr_td_with_scoping2(Pred,SubH,TSubH,LocalIds),
2494 l_transform_bexpr_td_with_scoping(T,Pred,TT,LocalIds).
2495
2496
2497 % apply a predicate over a syntax tree (bottom-up) with Accumulator result
2498 % Accumulator is constructed bottom up; Pred receives *all* accumulators of sub expressions
2499
2500 transform_bexpr_with_bup_accs(Pred,b(Expr,Type,Info),NewBExpr,EmptyAcc,Acc) :-
2501 syntaxtransformation(Expr,Subs,_Names,NSubs,NewExpr1),
2502 l_transform_bexpr_with_bup_accs(Subs,Pred,NSubs,EmptyAcc,SubAccs),
2503 (call(Pred,b(NewExpr1,Type,Info),NewBExpr,SubAccs,Acc) -> true
2504 ; NewBExpr = b(NewExpr1,Type,Info), Acc = EmptyAcc).
2505
2506 l_transform_bexpr_with_bup_accs([],_,[],_,[]).
2507 l_transform_bexpr_with_bup_accs([SubH|T],Pred,[TSubH|TT],EmptyAcc,[Acc1|RestAcc]) :-
2508 transform_bexpr_with_bup_accs(Pred,SubH,TSubH,EmptyAcc,Acc1),
2509 l_transform_bexpr_with_bup_accs(T,Pred,TT,EmptyAcc,RestAcc).
2510
2511 % apply a predicate over a syntax tree (bottom-up) with Accumulator result
2512 % a single Accumulator is passed along
2513
2514 transform_bexpr_with_acc(_Pred,E,NewBExpr,InAcc,Acc) :- var(E),!,
2515 NewBExpr=E, Acc=InAcc.
2516 transform_bexpr_with_acc(Pred,b(Expr,Type,Info),NewBExpr,InAcc,Acc) :-
2517 syntaxtransformation(Expr,Subs,_Names,NSubs,NewExpr1),
2518 l_transform_bexpr_with_acc(Subs,Pred,NSubs,InAcc,SubAcc),
2519 (call(Pred,b(NewExpr1,Type,Info),NewBExpr,SubAcc,Acc) -> true
2520 ; NewBExpr = b(NewExpr1,Type,Info), Acc = SubAcc).
2521
2522 l_transform_bexpr_with_acc([],_,[],Acc,Acc).
2523 l_transform_bexpr_with_acc([SubH|T],Pred,[TSubH|TT],InAcc,ResAcc) :-
2524 transform_bexpr_with_acc(Pred,SubH,TSubH,InAcc,Acc1),
2525 l_transform_bexpr_with_acc(T,Pred,TT,Acc1,ResAcc).
2526
2527 % a non-deterministic version of this
2528 non_det_transform_bexpr_with_acc(_Pred,E,NewBExpr,InAcc,Acc) :- var(E),!,
2529 NewBExpr=E, Acc=InAcc.
2530 non_det_transform_bexpr_with_acc(Pred,b(Expr,Type,Info),NewBExpr,InAcc,Acc) :-
2531 syntaxtransformation(Expr,Subs,_Names,NSubs,NewExpr1),
2532 l_nd_transform_bexpr_with_acc(Subs,Pred,NSubs,InAcc,SubAcc),
2533 if(call(Pred,b(NewExpr1,Type,Info),NewBExpr,SubAcc,Acc),
2534 true,
2535 (NewBExpr = b(NewExpr1,Type,Info), Acc = SubAcc)).
2536
2537 l_nd_transform_bexpr_with_acc([],_,[],Acc,Acc).
2538 l_nd_transform_bexpr_with_acc([SubH|T],Pred,[TSubH|TT],InAcc,ResAcc) :-
2539 non_det_transform_bexpr_with_acc(Pred,SubH,TSubH,InAcc,Acc1),
2540 l_nd_transform_bexpr_with_acc(T,Pred,TT,Acc1,ResAcc).
2541
2542
2543 % -------------------------
2544
2545 min_max_integer_value_used(BExpr,Min,Max) :-
2546 min_max_integer_value_used(BExpr,none,none,Min,Max).
2547 min_max_integer_value_used(BExpr,IMin,IMax,Min,Max) :-
2548 reduce_over_bexpr(min_max_aux,BExpr,minmax(IMin,IMax),minmax(Min,Max)).
2549
2550 min_max_aux(sequence_extension(L),minmax(Min,Max),minmax(NMin,NMax)) :- !,
2551 length(L,Len), % we use implicitly numbers from 1..Len
2552 (number(Min),1>Min -> NMin=Min ; NMin=1),
2553 (number(Max),Len<Max -> NMax=Max ; NMax=Len).
2554 min_max_aux(integer(N),minmax(Min,Max),minmax(NMin,NMax)) :- !,
2555 (number(Min),N>Min -> NMin=Min ; NMin=N),
2556 (number(Max),N<Max -> NMax=Max ; NMax=N).
2557 min_max_aux(_,V,V).
2558
2559 % check if a B expression uses something like NAT,NAT1,INT, MAXINT or MININT.
2560 uses_implementable_integers(BExpr) :-
2561 map_over_bexpr(uses_implementable_integers_aux,BExpr).
2562
2563 uses_implementable_integers_aux(maxint).
2564 uses_implementable_integers_aux(minint).
2565 uses_implementable_integers_aux(integer_set(X)) :-
2566 (X='NAT1' ; X='NAT' ; X='INT').
2567
2568 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2569 % some checks
2570 check_if_typed_predicate(b(Pred,X,_)) :- ground(X), X=pred, % at runtime there can be value(X) with variables inside !
2571 syntaxelement(Pred,_,_,_,_,TypePred), (TypePred=pred -> true ; TypePred = pred/only_typecheck).
2572 check_if_typed_expression(b(Expr,Type,_)) :-
2573 syntaxelement(Expr,_,_,_,_,TypeExpr),
2574 (TypeExpr=expr -> true ; TypeExpr = expr/only_typecheck),
2575 Type \== pred, Type \== subst, ground(Type).
2576 check_if_typed_substitution(b(Subst,X,_)) :- ground(X), X=subst,
2577 syntaxelement(Subst,_,_,_,_,subst).
2578
2579 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2580 % transformations
2581
2582 syntaxtransformation(Expr,Subs,Names,NSubs,NExpr) :-
2583 functor(Expr,F,Arity),
2584 functor(NExpr,F,Arity),
2585 safe_syntaxelement(Expr,Subs,Names,Lists,Constant),
2586 all_same_length(Lists,NLists),
2587 syntaxelement(NExpr,NSubs,_,NLists,Constant,_).
2588 % a faster non-backtracking version:
2589 syntaxtransformation_det(Expr,Subs,Names,NSubs,NExpr) :-
2590 functor(Expr,F,Arity),
2591 functor(NExpr,F,Arity),
2592 safe_syntaxelement_det(Expr,Subs,Names,Lists,Constant),
2593 all_same_length(Lists,NLists),
2594 syntaxelement(NExpr,NSubs,_,NLists,Constant,_).
2595
2596
2597 safe_syntaxelement(Expr,Subs,Names,Lists,Constant) :-
2598 ( syntaxelement(Expr,SubsX,NamesX,Lists,ConstantX,_) ->
2599 Subs=SubsX, Names=NamesX, Constant=ConstantX
2600 %(Subs,Names,Constant)=(SubsX,NamesX,ConstantX)
2601 ;
2602 functor(Expr,F,Arity),
2603 add_error_fail(bsyntaxtree,'Uncovered syntax element: ', F/Arity)
2604 ).
2605 % a faster non-backtracking version of safe_syntaxelement, assuming Subs, Names, ... are fresh vars
2606 safe_syntaxelement_det(Expr,Subs,Names,Lists,Constant) :-
2607 (syntaxelement(Expr,Subs,Names,Lists,Constant,_) -> true
2608 ; functor(Expr,F,Arity),
2609 add_error_fail(bsyntaxtree,'Uncovered syntax element: ', F/Arity)).
2610
2611 is_subst_syntaxelement(Subst) :-
2612 syntaxelement(Subst,_,_,_,_,subst).
2613
2614 % check if we have a syntax node without parameters
2615 is_syntax_constant(Expr) :- atom(Expr), syntaxelement(Expr,_,_,_,_,_).
2616
2617 % syntaxelement(Expr,SubExprs,Identifiers,Lists,Constant,Type):
2618 % Expr: the expression itself
2619 % SubExprs: a list of sub-expressions
2620 % Identifiers: a list of identifiers that are newly introduced (e.g. by a quantifier)
2621 % Lists: A list of lists in the expression, to prevent infinite loops when having variable parts
2622 % Constant: A part of the expression that is not a sub-expression (e.g. the number in integer(...))
2623 % Type: Fundamental type of the element (predicate, expression, etc)
2624
2625 % predicates
2626 syntaxelement(truth, [], [], [], [], pred).
2627 syntaxelement(falsity, [], [], [], [], pred).
2628 syntaxelement(unknown_truth_value(Msg),[], [], [], Msg, pred). % artificial, e.g., created by well_def_analyser
2629 syntaxelement(conjunct(A,B), [A,B],[], [], [], pred).
2630 %syntaxelement(conjunct(As), As, [], [], [], pred). % TO DO: support associative version of conjunct
2631 syntaxelement(negation(A), [A], [], [], [], pred).
2632 syntaxelement(disjunct(A,B), [A,B],[], [], [], pred).
2633 syntaxelement(implication(A,B), [A,B],[], [], [], pred).
2634 syntaxelement(equivalence(A,B), [A,B],[], [], [], pred).
2635 syntaxelement(equal(A,B), [A,B],[], [], [], pred).
2636 syntaxelement(not_equal(A,B), [A,B],[], [], [], pred).
2637 syntaxelement(member(A,B), [A,B],[], [], [], pred).
2638 syntaxelement(not_member(A,B), [A,B],[], [], [], pred).
2639 syntaxelement(subset(A,B), [A,B],[], [], [], pred).
2640 syntaxelement(subset_strict(A,B), [A,B],[], [], [], pred).
2641 syntaxelement(not_subset(A,B), [A,B],[], [], [], pred).
2642 syntaxelement(not_subset_strict(A,B),[A,B],[], [], [], pred).
2643 syntaxelement(less_equal(A,B), [A,B],[], [], [], pred).
2644 syntaxelement(less(A,B), [A,B],[], [], [], pred).
2645 syntaxelement(less_equal_real(A,B), [A,B],[], [], [], pred).
2646 syntaxelement(less_real(A,B), [A,B],[], [], [], pred).
2647 syntaxelement(greater_equal(A,B), [A,B],[], [], [], pred).
2648 syntaxelement(greater(A,B), [A,B],[], [], [], pred).
2649 syntaxelement(forall(Ids,D,P), [D,P|Ids],Ids,[Ids], [], pred).
2650 syntaxelement(exists(Ids,P), [P|Ids], Ids,[Ids], [], pred).
2651 syntaxelement(finite(A), [A], [], [], [], pred/only_typecheck).
2652 syntaxelement(partition(S,Es), [S|Es],[],[Es],[],pred).
2653 syntaxelement(kodkod(PId,Ids), Ids,[],[Ids],PId, pred).
2654 syntaxelement(external_pred_call(F,Args),Args,[],[Args],F,pred).
2655
2656 % expressions
2657 syntaxelement(value(V), [], [], [], V, expr).
2658 syntaxelement(operation_call_in_expr(Id,As), As, [], [As], Id, expr). % Do not treat Id as a sub-expression for find_identifier_uses, ...
2659 %syntaxelement(operation_call_in_expr(Id,As), [Id|As], [], [As], [], expr). % was like this, but changed to avoid op(.) ids in find_identifier_uses
2660 syntaxelement(boolean_true, [], [], [], [], expr).
2661 syntaxelement(boolean_false, [], [], [], [], expr).
2662 syntaxelement(max_int, [], [], [], [], expr).
2663 syntaxelement(min_int, [], [], [], [], expr).
2664 syntaxelement(empty_set, [], [], [], [], expr).
2665 syntaxelement(bool_set, [], [], [], [], expr).
2666 syntaxelement(float_set, [], [], [], [], expr).
2667 syntaxelement(real(I), [], [], [], I, expr).
2668 syntaxelement(real_set, [], [], [], [], expr).
2669 syntaxelement(string_set, [], [], [], [], expr).
2670 syntaxelement(convert_bool(A), [A], [], [], [], expr).
2671 syntaxelement(convert_real(A), [A], [], [], [], expr).
2672 syntaxelement(convert_int_floor(A), [A], [], [], [], expr).
2673 syntaxelement(convert_int_ceiling(A), [A], [], [], [], expr).
2674 syntaxelement(add(A,B), [A,B],[], [], [], expr).
2675 syntaxelement(add_real(A,B), [A,B],[], [], [], expr).
2676 syntaxelement(minus(A,B), [A,B],[], [], [], expr).
2677 syntaxelement(minus_real(A,B), [A,B],[], [], [], expr).
2678 syntaxelement(minus_or_set_subtract(A,B),[A,B],[], [], [], expr/only_typecheck).
2679 syntaxelement(unary_minus(A), [A], [], [], [], expr).
2680 syntaxelement(unary_minus_real(A), [A], [], [], [], expr).
2681 syntaxelement(multiplication(A,B), [A,B],[], [], [], expr).
2682 syntaxelement(multiplication_real(A,B),[A,B],[], [], [], expr).
2683 syntaxelement(mult_or_cart(A,B), [A,B],[], [], [], expr/only_typecheck).
2684 syntaxelement(cartesian_product(A,B), [A,B],[], [], [], expr).
2685 syntaxelement(div(A,B), [A,B],[], [], [], expr).
2686 syntaxelement(div_real(A,B), [A,B],[], [], [], expr).
2687 syntaxelement(floored_div(A,B), [A,B],[], [], [], expr).
2688 syntaxelement(modulo(A,B), [A,B],[], [], [], expr).
2689 syntaxelement(power_of(A,B), [A,B],[], [], [], expr).
2690 syntaxelement(power_of_real(A,B), [A,B],[], [], [], expr).
2691 syntaxelement(successor, [], [], [], [], expr).
2692 syntaxelement(predecessor, [], [], [], [], expr).
2693 syntaxelement(max(A), [A], [], [], [], expr).
2694 syntaxelement(max_real(A), [A], [], [], [], expr).
2695 syntaxelement(min(A), [A], [], [], [], expr).
2696 syntaxelement(min_real(A), [A], [], [], [], expr).
2697 syntaxelement(card(A), [A], [], [], [], expr).
2698 syntaxelement(couple(A,B), [A,B],[], [], [], expr).
2699 syntaxelement(pow_subset(A), [A], [], [], [], expr).
2700 syntaxelement(pow1_subset(A), [A], [], [], [], expr).
2701 syntaxelement(fin_subset(A), [A], [], [], [], expr).
2702 syntaxelement(fin1_subset(A), [A], [], [], [], expr).
2703 syntaxelement(interval(A,B), [A,B],[], [], [], expr).
2704 syntaxelement(union(A,B), [A,B],[], [], [], expr).
2705 syntaxelement(intersection(A,B), [A,B],[], [], [], expr).
2706 syntaxelement(set_subtraction(A,B), [A,B],[], [], [], expr).
2707 syntaxelement(general_union(A), [A], [], [], [], expr).
2708 syntaxelement(general_intersection(A), [A] , [], [], [], expr).
2709 syntaxelement(relations(A,B), [A,B],[], [], [], expr).
2710 syntaxelement(identity(A), [A], [], [], [], expr).
2711 syntaxelement(event_b_identity, [], [], [], [], expr). % for Rodin 1.0, TO DO: Daniel please check
2712 syntaxelement(reverse(A), [A], [], [], [], expr).
2713 syntaxelement(first_projection(A,B), [A,B],[], [], [], expr/only_typecheck).
2714 syntaxelement(first_of_pair(A), [A], [], [], [], expr).
2715 syntaxelement(event_b_first_projection(A),[A], [], [], [], expr/only_typecheck).
2716 syntaxelement(event_b_first_projection_v2,[], [], [], [], expr/only_typecheck). % for Rodin 1.0, TO DO: Daniel please check
2717 syntaxelement(second_projection(A,B), [A,B],[], [], [], expr/only_typecheck).
2718 syntaxelement(event_b_second_projection_v2,[], [], [], [], expr/only_typecheck). % for Rodin 1.0, TO DO: Daniel please check
2719 syntaxelement(second_of_pair(A), [A], [], [], [], expr).
2720 syntaxelement(event_b_second_projection(A),[A], [], [], [], expr/only_typecheck).
2721 syntaxelement(composition(A,B), [A,B],[], [], [], expr).
2722 syntaxelement(ring(A,B), [A,B],[], [], [], expr/only_typecheck).
2723 syntaxelement(direct_product(A,B), [A,B],[], [], [], expr).
2724 syntaxelement(parallel_product(A,B), [A,B],[], [], [], expr).
2725 syntaxelement(trans_function(A), [A], [], [], [], expr).
2726 syntaxelement(trans_relation(A), [A], [], [], [], expr).
2727 syntaxelement(iteration(A,B), [A,B],[], [], [], expr).
2728 syntaxelement(reflexive_closure(A), [A], [], [], [], expr).
2729 syntaxelement(closure(A), [A], [], [], [], expr).
2730 syntaxelement(domain(A), [A], [], [], [], expr).
2731 syntaxelement(range(A), [A], [], [], [], expr).
2732 syntaxelement(image(A,B), [A,B],[], [], [], expr).
2733 syntaxelement(domain_restriction(A,B), [A,B],[], [], [], expr).
2734 syntaxelement(domain_subtraction(A,B), [A,B],[], [], [], expr).
2735 syntaxelement(range_restriction(A,B), [A,B],[], [], [], expr).
2736 syntaxelement(range_subtraction(A,B), [A,B],[], [], [], expr).
2737 syntaxelement(overwrite(A,B), [A,B],[], [], [], expr).
2738 syntaxelement(partial_function(A,B), [A,B],[], [], [], expr).
2739 syntaxelement(total_function(A,B), [A,B],[], [], [], expr).
2740 syntaxelement(partial_injection(A,B), [A,B],[], [], [], expr).
2741 syntaxelement(total_injection(A,B), [A,B],[], [], [], expr).
2742 syntaxelement(partial_surjection(A,B), [A,B],[], [], [], expr).
2743 syntaxelement(total_surjection(A,B), [A,B],[], [], [], expr).
2744 syntaxelement(total_bijection(A,B), [A,B],[], [], [], expr).
2745 syntaxelement(partial_bijection(A,B), [A,B],[], [], [], expr).
2746 syntaxelement(total_relation(A,B), [A,B],[], [], [], expr).
2747 syntaxelement(surjection_relation(A,B),[A,B],[], [], [], expr).
2748 syntaxelement(total_surjection_relation(A,B),[A,B],[], [], [], expr).
2749 syntaxelement(seq(A), [A], [], [], [], expr).
2750 syntaxelement(seq1(A), [A], [], [], [], expr).
2751 syntaxelement(iseq(A), [A], [], [], [], expr).
2752 syntaxelement(iseq1(A), [A], [], [], [], expr).
2753 syntaxelement(perm(A), [A], [], [], [], expr).
2754 syntaxelement(empty_sequence, [], [], [], [], expr).
2755 syntaxelement(size(A), [A], [], [], [], expr).
2756 syntaxelement(first(A), [A], [], [], [], expr).
2757 syntaxelement(last(A), [A], [], [], [], expr).
2758 syntaxelement(front(A), [A], [], [], [], expr).
2759 syntaxelement(tail(A), [A], [], [], [], expr).
2760 syntaxelement(rev(A), [A], [], [], [], expr).
2761 syntaxelement(concat(A,B), [A,B],[], [], [], expr).
2762 syntaxelement(insert_front(A,B), [A,B],[], [], [], expr).
2763 syntaxelement(insert_tail(A,B), [A,B],[], [], [], expr).
2764 syntaxelement(restrict_front(A,B), [A,B],[], [], [], expr).
2765 syntaxelement(restrict_tail(A,B), [A,B],[], [], [], expr).
2766 syntaxelement(general_concat(A), [A], [], [], [], expr).
2767 syntaxelement(function(A,B), [A,B],[], [], [], expr).
2768 syntaxelement(external_function_call(F,Args),Args,[],[Args],F,expr).
2769 syntaxelement(identifier(I), [], [], [], I, expr).
2770 syntaxelement(lazy_lookup_expr(I), [], [], [], I, expr).
2771 syntaxelement(lazy_lookup_pred(I), [], [], [], I, pred).
2772 syntaxelement(integer(I), [], [], [], I, expr).
2773 syntaxelement(integer_set(T), [], [], [], T, expr).
2774 syntaxelement(string(S), [], [], [], S, expr).
2775 syntaxelement(set_extension(L), L, [], [L], [], expr).
2776 syntaxelement(sequence_extension(L), L, [], [L], [], expr).
2777 syntaxelement(comprehension_set(Ids,P),[P|Ids], Ids,[Ids], [], expr).
2778 syntaxelement(event_b_comprehension_set(Ids,E,P),[E,P|Ids], Ids,[Ids], [], expr/only_typecheck).
2779 syntaxelement(lambda(Ids,P,E), [P,E|Ids],Ids,[Ids], [], expr).
2780 syntaxelement(general_sum(Ids,P,E), [P,E|Ids],Ids,[Ids], [], expr).
2781 syntaxelement(general_product(Ids,P,E), [P,E|Ids],Ids,[Ids], [], expr).
2782 syntaxelement(quantified_union(Ids,P,E), [P,E|Ids],Ids,[Ids], [], expr).
2783 syntaxelement(quantified_intersection(Ids,P,E), [P,E|Ids],Ids,[Ids], [], expr).
2784 syntaxelement(struct(Rec), [Rec], [], [], [], expr).
2785 syntaxelement(rec(Fields), FContent, [], [FContent], FNames, expr) :- syntaxfields(Fields,FContent, FNames).
2786 syntaxelement(record_field(R,I), [R], [], [], I, expr).
2787 syntaxelement(assertion_expression(Cond,ErrMsg,Expr), [Cond,Expr], [], [], ErrMsg, expr).
2788 syntaxelement(typeset, [], [], [], [], expr/only_typecheck).
2789
2790 syntaxelement(tree(A), [A], [], [], [], expr).
2791 syntaxelement(btree(A), [A], [], [], [], expr).
2792 syntaxelement(const(A,B), [A,B],[], [], [], expr).
2793 syntaxelement(top(A), [A], [], [], [], expr).
2794 syntaxelement(sons(A), [A], [], [], [], expr).
2795 syntaxelement(prefix(A), [A], [], [], [], expr).
2796 syntaxelement(postfix(A), [A], [], [], [], expr).
2797 syntaxelement(sizet(A), [A], [], [], [], expr).
2798 syntaxelement(mirror(A), [A], [], [], [], expr).
2799 syntaxelement(rank(A,B), [A,B],[], [], [], expr).
2800 syntaxelement(father(A,B), [A,B],[], [], [], expr).
2801 syntaxelement(son(A,B,C), [A,B,C],[], [], [], expr).
2802 syntaxelement(subtree(A,B), [A,B],[], [], [], expr).
2803 syntaxelement(arity(A,B), [A,B],[], [], [], expr).
2804 syntaxelement(bin(A), [A],[], [], [], expr).
2805 syntaxelement(bin(A,B,C), [A,B,C],[], [], [], expr).
2806 syntaxelement(infix(A), [A], [], [], [], expr).
2807 syntaxelement(left(A), [A], [], [], [], expr).
2808 syntaxelement(right(A), [A], [], [], [], expr).
2809
2810 % substitutions
2811 syntaxelement(skip, [], [], [], [], subst).
2812 syntaxelement(precondition(A,B), [A,B],[], [], [], subst).
2813 syntaxelement(assertion(A,B), [A,B],[], [], [], subst).
2814 syntaxelement(witness_then(A,B), [A,B],[], [], [], subst).
2815 syntaxelement(if_elsif(A,B), [A,B],[], [], [], subst/elsif).
2816 syntaxelement(while(A,B,C,D), [A,B,C,D],[], [], [], subst).
2817 % used only internally in the interpreter, contains last value of variant:
2818 syntaxelement(while1(A,B,C,D,E), [A,B,C,D],[], [], E, subst).
2819 syntaxelement(select_when(A,B), [A,B],[], [], [], subst/when).
2820 syntaxelement(block(S),[S],[],[],[], subst/only_typecheck).
2821 syntaxelement(assign(Lhs,Rhs),Exprs,[],[Lhs,Rhs], [], subst) :- append(Lhs,Rhs,Exprs).
2822 syntaxelement(assign_single_id(Id,Rhs),[Id,Rhs],[],[], [], subst).
2823 syntaxelement(any(Ids,P,S),[P,S|Ids],Ids,[Ids], [], subst).
2824 syntaxelement(var(Ids,S), [S|Ids], Ids,[Ids], [], subst).
2825 syntaxelement(if(Ifs), Ifs, [], [Ifs], [], subst).
2826 syntaxelement(parallel(Ss), Ss, [], [Ss], [], subst).
2827 syntaxelement(sequence(Ss), Ss, [], [Ss], [], subst).
2828 syntaxelement(becomes_element_of(Ids,E), [E|Ids], [], [Ids], [], subst).
2829 syntaxelement(becomes_such(Ids,P), [P|Ids], [], [Ids], [], subst). % Ids are new value, Ids$0 is old value
2830 syntaxelement(evb2_becomes_such(Ids,P), [P|Ids], [], [Ids], [], subst/only_typecheck).
2831 syntaxelement(let(Ids,P,S), [P,S|Ids], Ids, [Ids], [], subst).
2832 syntaxelement(operation_call(Id,Rs,As), [Id|Exprs], [], [Rs,As], [], subst) :- append(Rs,As,Exprs).
2833 syntaxelement(case(E,Eithers,Else), [E,Else|Eithers], [], [Eithers], [], subst).
2834 syntaxelement(case_or(Es,S), [S|Es], [], [Es], [], subst/caseor).
2835 syntaxelement(choice(Ss), Ss, [], [Ss], [], subst).
2836 syntaxelement(select(Whens), Whens, [], [Whens], [], subst).
2837 syntaxelement(select(Whens,Else), [Else|Whens], [], [Whens], [], subst).
2838 syntaxelement(operation(I,Rs,As,B), [I,B|Ids], Ids, [Rs,As], [], subst) :- append(Rs,As,Ids).
2839 syntaxelement(external_subst_call(F,Args),Args,[],[Args],F,subst).
2840
2841 % elements of a VALUES clause
2842 syntaxelement(values_entry(I,E),[I,E],[],[],[],values_entry).
2843
2844 % syntax for Event-B events
2845 syntaxelement(rlevent(I,Sec,St,Ps,G,Ts,As,VWs,PWs,Ums,Rs), Subs, [], [Ps,Ts,As,VWs,PWs,Ums,Rs], [I,Sec], subst) :-
2846 append([[St],Ps,[G],Ts,As,VWs,PWs,Ums,Rs],Subs).
2847 syntaxelement(witness(I,P), [I,P], [], [], [], witness).
2848
2849 % extended syntax for Z
2850 syntaxelement(let_predicate(Ids,As,Pred), Exprs, Ids, [Ids,As], [], pred) :- append([Ids,As,[Pred]],Exprs).
2851 syntaxelement(let_expression(Ids,As,Expr), Exprs, Ids, [Ids,As], [], expr) :- append([Ids,As,[Expr]],Exprs).
2852 syntaxelement(let_expression_global(Ids,As,Expr), Exprs, Ids, [Ids,As], [], expr) :- % version used by b_compiler
2853 append([Ids,As,[Expr]],Exprs).
2854 syntaxelement(lazy_let_expr(TID,A,Expr), [TID, A, Expr], [TID], [[TID],[A]], [], expr).
2855 syntaxelement(lazy_let_pred(TID,A,Expr), [TID, A, Expr], [TID], [[TID],[A]], [], pred).
2856 syntaxelement(lazy_let_subst(TID,A,Expr), [TID, A, Expr], [TID], [[TID],[A]], [], subst).
2857 syntaxelement(if_then_else(If,Then,Else),[If,Then,Else], [], [], [], expr).
2858 syntaxelement(compaction(A), [A], [], [], [], expr).
2859 syntaxelement(mu(A), [A], [], [], [], expr).
2860 syntaxelement(bag_items(A), [A], [], [], [], expr).
2861
2862 syntaxelement(freetype_set(Id), [], [], [], Id, expr).
2863 syntaxelement(freetype_case(Type,Case,Expr), [Expr], [], [], [Type,Case], pred).
2864 syntaxelement(freetype_constructor(Type,Case,Expr), [Expr], [], [], [Type,Case], expr).
2865 syntaxelement(freetype_destructor(Type,Case,Expr), [Expr], [], [], [Type,Case], expr).
2866
2867 syntaxelement(ordinary, [], [], [], [], status).
2868 syntaxelement(anticipated(Variant), [Variant], [], [], [], status).
2869 syntaxelement(convergent(Variant), [Variant], [], [], [], status).
2870
2871 % Just one ID expected
2872 syntaxelement(recursive_let(Id,C),[Id,C],[Id],[],[], expr). % Note: Id is not really introduced !
2873
2874
2875 % fields of records
2876 %syntaxfields(Fields,C,_) :- var(Fields),var(C),var(N),!, add_internal_error('Illegal call: ',syntaxfields(Fields,C,N)),fail.
2877 syntaxfields([],[],[]).
2878 syntaxfields([field(N,C)|Rest],[C|CRest],[N|NRest]) :- syntaxfields(Rest,CRest,NRest).
2879
2880 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2881 % helper for declaration of quantified identifiers
2882
2883 % has_declared_identifier/2 returns a list of identifiers which are declared in
2884 % this AST node. The main difference to the Names variable when doing a
2885 % syntaxtraversion/6 or similiar is that the identifiers are described by
2886 % predicates.
2887 has_declared_identifier(TExpr,Ids) :-
2888 get_texpr_expr(TExpr,Expr),
2889 ( default_declaration(Expr,_,Ids,_)
2890 ; non_default_declaration(Expr,Ids)).
2891
2892 add_declaration_for_identifier(b(Expr,Type,Infos),Decl,b(NExpr,Type,NewInfos)) :-
2893 %delete(Infos,used_ids(_),NewInfos), % we cannot
2894 ( default_declaration(Expr,Predicate,Ids,Constant) ->
2895 same_functor(Expr,NExpr),
2896 conjunct_predicates([Decl,Predicate],NPredicate),
2897 default_declaration(NExpr,NPredicate,Ids,Constant)
2898 ; non_default_declaration(Expr,Ids) ->
2899 add_non_default_declaration(Expr,Decl,NExpr)
2900 ),
2901 add_used_ids(Infos,Ids,Decl,NewInfos).
2902
2903 % add used ids of a predicate within quantification of Ids to current used_ids info; if it is there
2904 add_used_ids(Infos,Ids,Pred,NewInfos) :- update_used_ids(Infos,OldUsed,NewInfos,NewUsed),
2905 !, % a field needs updating
2906 find_identifier_uses(Pred,[],NewIds), get_texpr_ids(Ids,UnsortedIds),sort(UnsortedIds,SIds),
2907 ord_subtract(NewIds,SIds,NewIds2),
2908 ord_union(NewIds2,OldUsed,NewUsed).
2909 add_used_ids(I,_,_,I).
2910
2911 % just update used_ids field (e.g., when just computed to store it for later)
2912 update_used_ids(Infos,OldUsed,NewInfos,NewUsed) :- select(OldInfo,Infos,I1),
2913 used_ids_like_info(OldInfo,F,OldUsed),!,
2914 used_ids_like_info(NewInfo,F,NewUsed),NewInfos = [NewInfo|I1].
2915
2916 % info fields which contain used_ids information
2917 used_ids_like_info(used_ids(UsedIds),used_ids,UsedIds).
2918 used_ids_like_info(reads(UsedIds),reads,UsedIds).
2919
2920 :- use_module(probsrc(btypechecker), [prime_identifiers/2]).
2921
2922 % default_declaration(Expr,Predicate,Ids,Constant)
2923 default_declaration(forall(Ids,D,P),D,Ids,P).
2924 default_declaration(exists(Ids,P),P,Ids,[]).
2925 default_declaration(comprehension_set(Ids,P),P,Ids,[]).
2926 default_declaration(event_b_comprehension_set(Ids,E,P),P,Ids,E). % translated !?
2927 default_declaration(lambda(Ids,P,E),P,Ids,E).
2928 default_declaration(general_sum(Ids,P,E),P,Ids,E).
2929 default_declaration(general_product(Ids,P,E),P,Ids,E).
2930 default_declaration(quantified_union(Ids,P,E),P,Ids,E).
2931 default_declaration(quantified_intersection(Ids,P,E),P,Ids,E).
2932 default_declaration(any(Ids,P,S),P,Ids,S).
2933 default_declaration(becomes_such(Ids,P),P,Ids,[]).
2934 default_declaration(evb2_becomes_such(Ids,P),P,Primed,[]) :-
2935 nl,print(evb2(Ids,Primed)),nl,nl, % no longer used, as it is translated to becomes_such
2936 prime_identifiers(Ids,Primed).
2937 default_declaration(rlevent(I,Sec,St,Ps,G,Ts,As,VWs,PWs,Ums,Rs),G,Ps,
2938 [I,Sec,St,Ps,Ts,As,VWs,PWs,Ums,Rs]).
2939 default_declaration(let_predicate(Ids,Ps,Body),Ps,Ids,Body) :- print(let(Ids)),nl. % TODO: check format of Ps
2940 default_declaration(let_expression(Ids,Ps,Body),Ps,Ids,Body) :- print(let(Ids)),nl. % TODO: check format of Ps
2941 default_declaration(let_expression_global(Ids,Ps,Body),Ps,Ids,Body) :- print(let(Ids)),nl. % TODO: check format of Ps
2942 % TODO: lazy let ?
2943
2944 non_default_declaration(operation(_I,Rs,As,_TBody),Ids) :-
2945 append(Rs,As,Ids).
2946
2947 add_non_default_declaration(operation(I,Rs,As,TBody),Decl,operation(I,Rs,As,NTBody)) :-
2948 ( get_guard_and_copy(TBody,P,NP,NTBody) ->
2949 conjunct_predicates([Decl,P],NP)
2950 ; create_texpr(precondition(Decl,TBody),subst,[],NTBody)).
2951
2952 get_guard_and_copy(TBody,P,NP,NTBody) :- remove_bt(TBody,Body,NBody,NTBody),
2953 get_guard_copy2(Body,P,NP,NBody).
2954
2955 get_guard_copy2(precondition(P,S),P,NP,precondition(NP,S)).
2956 get_guard_copy2(rlevent(I,Sec,St,Ps, G,Ts,As,VWs,PWs,Ums,Rs), G, NG,
2957 rlevent(I,Sec,St,Ps,NG,Ts,As,VWs,PWs,Ums,Rs)).
2958
2959 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2960 % pattern definitions (not yet finished)
2961
2962 bsyntax_pattern(Expr,TExpr) :-
2963 var(Expr),!,Expr=TExpr.
2964 bsyntax_pattern(-Expr,TExpr) :-
2965 !,remove_all_infos(Expr,TExpr).
2966 bsyntax_pattern(Expr,TExpr) :-
2967 functor(Expr,b,3),!,Expr=TExpr.
2968 bsyntax_pattern(Expr:Type/Info,TExpr) :-
2969 !,bsyntax_pattern2(Expr,Type,Info,TExpr).
2970 bsyntax_pattern(Expr:Type,TExpr) :-
2971 !,bsyntax_pattern2(Expr,Type,_Info,TExpr).
2972 bsyntax_pattern(Expr/Info,TExpr) :-
2973 !,bsyntax_pattern2(Expr,_Type,Info,TExpr).
2974 bsyntax_pattern(Expr,TExpr) :-
2975 !,bsyntax_pattern2(Expr,_Type,_Info,TExpr).
2976
2977 bsyntax_pattern2(Pattern,Type,Info,TExpr) :-
2978 functor(Pattern,Functor,Arity),
2979 functor(R,Functor,Arity),
2980 create_texpr(R,Type,Info,TExpr),
2981 syntaxelement(Pattern,PSubs,_,PLists,Const,EType),
2982 syntaxelement(R,RSubs,_,RLists,Const,EType),
2983 ( EType==pred -> Type=pred
2984 ; EType==subst -> Type=subst
2985 ; true),
2986 all_same_length(PLists,RLists),
2987 maplist(bsyntax_pattern,PSubs,RSubs).
2988
2989 all_same_length([],[]).
2990 all_same_length([A|Arest],[B|Brest]) :-
2991 ( var(A),var(B) ->
2992 add_error_fail(bsyntaxtree,'At least one list should contain nonvar elements for all_same_length',[A,B])
2993 ;
2994 same_length(A,B)),
2995 all_same_length(Arest,Brest).
2996
2997 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2998 % strip an AST into a more compact form (without b/3 terms)
2999
3000 strip_and_norm_ast(TExpr,SNExpr) :-
3001 get_texpr_expr(TExpr,Expr),
3002 strip_and_norm_ast_aux(Expr,SNExpr).
3003
3004 :- use_module(tools,[safe_univ_no_cutoff/2]).
3005 strip_and_norm_ast_aux(Expr,Res) :-
3006 comm_assoc_subs(Expr,Op,Subs,[]), !, % associative & commutative operator detected
3007 maplist(strip_and_norm_ast_aux,Subs,NSubs), % Subs are already unwrapped
3008 sort(NSubs,Sorted), % in case there are associative operators that are not commutative: insert is_commutative check
3009 safe_univ_no_cutoff(Res,[Op|Sorted]).
3010 strip_and_norm_ast_aux(Expr,Res) :-
3011 assoc_subs(Expr,Op,Subs,[]), !, % associative operator detected
3012 maplist(strip_and_norm_ast_aux,Subs,NSubs), % Subs are already unwrapped
3013 safe_univ_no_cutoff(Res,[Op|NSubs]).
3014 strip_and_norm_ast_aux(Expr,SNExpr) :-
3015 syntaxtransformation(Expr,Subs,_,NSubs,SExpr),
3016 strip_and_norm_ast_l(Subs,NSubs),
3017 norm_strip(SExpr,SNExpr).
3018
3019 strip_and_norm_ast_l([],[]).
3020 strip_and_norm_ast_l([TExpr|Trest],[NExpr|Nrest]) :-
3021 strip_and_norm_ast(TExpr,NExpr),
3022 strip_and_norm_ast_l(Trest,Nrest).
3023
3024 norm_strip(greater_equal(A,B),less_equal(B,A)) :- !.
3025 norm_strip(greater(A,B),less(B,A)) :- !.
3026 norm_strip(set_extension(NL),set_extension(SNL)) :- !,
3027 sort(NL,SNL).
3028 norm_strip(Old,New) :-
3029 functor(Old,Functor,2),
3030 is_commutative(Functor),!,
3031 arg(1,Old,OA),
3032 arg(2,Old,OB),
3033 ( OA @> OB -> New =.. [Functor,OB,OA]
3034 ; New=Old).
3035 norm_strip(Old,Old).
3036 % TO DO: flatten associative operators into lists !
3037
3038 comm_assoc_subs(conjunct(TA,TB),conjunct) --> !,
3039 {get_texpr_expr(TA,A), get_texpr_expr(TB,B)},
3040 comm_assoc_subs(A,conjunct), comm_assoc_subs(B,conjunct).
3041 comm_assoc_subs(disjunct(TA,TB),disjunct) --> !,
3042 {get_texpr_expr(TA,A), get_texpr_expr(TB,B)},
3043 comm_assoc_subs(A,disjunct), comm_assoc_subs(B,disjunct).
3044 comm_assoc_subs(add(TA,TB),add) --> !,
3045 {get_texpr_expr(TA,A), get_texpr_expr(TB,B)},
3046 comm_assoc_subs(A,add), comm_assoc_subs(B,add).
3047 comm_assoc_subs(multiplication(TA,TB),multiplication) --> !,
3048 {get_texpr_expr(TA,A), get_texpr_expr(TB,B)},
3049 comm_assoc_subs(A,multiplication), comm_assoc_subs(B,multiplication).
3050 comm_assoc_subs(union(TA,TB),union) --> !,
3051 {get_texpr_expr(TA,A), get_texpr_expr(TB,B)},
3052 comm_assoc_subs(A,union), comm_assoc_subs(B,union).
3053 comm_assoc_subs(intersection(TA,TB),intersection) --> !,
3054 {get_texpr_expr(TA,A), get_texpr_expr(TB,B)},
3055 comm_assoc_subs(A,intersection), comm_assoc_subs(B,intersection).
3056 comm_assoc_subs(Expr,Op) --> {nonvar(Op)},[Expr]. % base case for other operators
3057
3058 % detect just associative operators
3059 assoc_subs(concat(TA,TB),concat) --> !,
3060 {get_texpr_expr(TA,A), get_texpr_expr(TB,B)},
3061 assoc_subs(A,concat), assoc_subs(B,concat).
3062 assoc_subs(composition(TA,TB),composition) --> !,
3063 {get_texpr_expr(TA,A), get_texpr_expr(TB,B)},
3064 assoc_subs(A,composition), assoc_subs(B,composition).
3065 assoc_subs(Expr,Op) --> {nonvar(Op)},[Expr]. % base case for other operators
3066
3067 is_commutative(conjunct).
3068 is_commutative(disjunct).
3069 is_commutative(equivalence).
3070 is_commutative(equal).
3071 is_commutative(not_equal).
3072 is_commutative(add).
3073 is_commutative(multiplication).
3074 is_commutative(union).
3075 is_commutative(intersection).
3076
3077 % check if two type expressions are same modulo info fields and reordering of commutative operators
3078 % same_texpr does not reorder wrt commutativity.
3079 same_norm_texpr(TExpr1,TExpr2) :-
3080 strip_and_norm_ast(TExpr1,N1),
3081 strip_and_norm_ast(TExpr2,N1).
3082
3083
3084 % small utility to get functor of texpr:
3085 get_texpr_functor(b(E,_,_),F,N) :- !, functor(E,F,N).
3086 get_texpr_functor(E,_,+) :- add_error_fail(get_texpr_functor,'Not a typed expression: ',E).
3087
3088 % -------------------------
3089
3090 % check if a ProB type is a set type:
3091 is_set_type(set(Type),Type).
3092 is_set_type(seq(Type),couple(integer,Type)).
3093 % should we have a rule for any ?? : in all cases using is_set_type any seems not possible; better that we generate error message in get_set_type or get_texpr_set_type
3094 % is_set_type(any,any).
3095
3096 get_set_type(TypeX,Res) :-
3097 ? (is_set_type(TypeX,SetType) -> Res=SetType ; add_error_fail(get_set_type,'Not a set type: ',TypeX)).
3098
3099 get_texpr_set_type(X,Res) :- get_texpr_type(X,TypeX),
3100 get_set_type(TypeX,Res).
3101
3102
3103 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
3104 % check if a set contains all elements of a type, i.e., maximal type
3105 is_just_type(Expr) :- is_just_type(Expr,[]).
3106 % is_just_type(+Expr,+RTT):
3107 % like is_just_type/1 but RTT is a list of identifiers (without type information)
3108 % of variables or constants that are known to be types, too.
3109 % E.g. is_just_type(a ** INTEGER) would fail but is_just_type(a ** INTEGER,[a]) would
3110 % succeed.
3111 is_just_type(b(E,T,I),RTT) :- is_just_type3(E,T,I,RTT).
3112
3113
3114 is_just_type3(identifier(G),SType,Infos,RefsToTypes) :-
3115 nonvar(SType), SType = set(Type), nonvar(Type),
3116 ( Type = global(G),
3117 memberchk(given_set,Infos) % no accidental local variable G that hides global G
3118 ; memberchk(G,RefsToTypes) -> true
3119 %; Type = freetype(G),
3120 % memberchk(given_set,Infos) % no accidental local variable G that hides global G
3121 % TODO: we do not know if the Freetype has restrictions (which are encoded in the PROPERTIES)
3122 ),!.
3123 is_just_type3(freetype_set(_),_,_,_).
3124 is_just_type3(pow_subset(E),_,_,RTT) :- is_just_type(E,RTT).
3125 is_just_type3(fin_subset(E),T,_,RTT) :-
3126 is_finite_type_in_context(proving,T), % animation or proving
3127 is_just_type(E,RTT).
3128 is_just_type3(integer_set('INTEGER'),set(integer),_,_).
3129 is_just_type3(bool_set,set(boolean),_,_).
3130 is_just_type3(real_set,set(real),_,_).
3131 is_just_type3(string_set,set(string),_,_).
3132 is_just_type3(cartesian_product(A,B),_,_,RTT) :-
3133 is_just_type(A,RTT),is_just_type(B,RTT).
3134 is_just_type3(mult_or_cart(A,B),_,_,RTT) :- % is_just_type/1 could be called before the cleanup
3135 is_just_type(A,RTT),is_just_type(B,RTT). % of an expression has finished
3136 is_just_type3(relations(A,B),_,_,RTT) :-
3137 is_just_type(A,RTT),is_just_type(B,RTT).
3138 is_just_type3(struct(b(rec(Fields),_,_)),_,_,RTT) :-
3139 maplist(field_is_just_type(RTT),Fields).
3140 is_just_type3(typeset,_,_,_).
3141 is_just_type3(comprehension_set(_,b(truth,_,_)),_,_,_).
3142 is_just_type3(set_extension([V1,V2]),_,_,_) :- get_texpr_boolean(V1,B1), % TODO: also deal with enumerated set elems
3143 (B1=boolean_true -> get_texpr_boolean(V2,boolean_false) ; B1=boolean_false -> get_texpr_boolean(V2,boolean_true)).
3144 is_just_type3(value(Val),ST,_,_) :- % e.g., {TRUE,FALSE} would usually get translated into this
3145 is_set_type(ST,Type), is_maximal_value(Val,Type). % also see: quick_is_definitely_maximal_set(Val).
3146
3147 field_is_just_type(RTT,field(_,Set)) :- is_just_type(Set,RTT).
3148
3149
3150 get_texpr_boolean(b(X,_,_),Res) :- is_boolan_expr(X,Res).
3151 is_boolan_expr(boolean_true,boolean_true).
3152 is_boolan_expr(boolean_false,boolean_false).
3153 is_boolan_expr(value(X),Res) :- nonvar(X), conv_bool_val(X,Res).
3154 conv_bool_val(pred_true,boolean_true).
3155 conv_bool_val(pred_false,boolean_false).
3156
3157 :- use_module(probsrc(custom_explicit_sets),[quick_definitely_maximal_set_avl/1]).
3158 is_maximal_value(V,_) :- var(V),!,fail.
3159 is_maximal_value(global_set(GS),Type) :- (GS=='INTEGER' -> true ; Type==global(GS)).
3160 % we could call is_maximal_global_set(GS) or b_global_set (but requires compiled)
3161 is_maximal_value(avl_set(A),Type) :-
3162 type_finite_and_pre_compiled(Type),
3163 quick_definitely_maximal_set_avl(A). % note: affects test 2392
3164
3165 :- use_module(probsrc(b_global_sets),[b_global_sets_precompiled/0, enumerated_sets_precompiled/0, enumerated_set/1]).
3166 type_finite_and_pre_compiled(boolean).
3167 type_finite_and_pre_compiled(global(GS)) :-
3168 (enumerated_set(GS) -> true % at least added with pre_register_enumerated_set_with_elems
3169 ; b_global_sets_precompiled).
3170 type_finite_and_pre_compiled(couple(A,B)) :- type_finite_and_pre_compiled(A), type_finite_and_pre_compiled(B).
3171 type_finite_and_pre_compiled(set(A)) :- type_finite_and_pre_compiled(A).
3172 % TODO: records?? less-likely we have an exhaustive list
3173
3174 % Generate a custom matching / visitor predicate
3175 % bsyntaxtree:gen_visitor(bexpr_variables_aux,bexpr_variables)
3176 /*
3177 gen_visitor(Pred, BodyPred) :- syntaxelement(Expr,SubsX,_NamesX,_Lists,_ConstantX,_),
3178 print_clause(Pred,BodyPred,Expr,SubsX),
3179 fail.
3180 gen_visitor(Pred, BodyPred) :- nl.
3181
3182 print_clause(Pred,BodyPred,Expr,SubsX) :- E=..[Op|SubsX], format('~w(~w) :- ',[Pred,Expr]).
3183 */
3184
3185 /*
3186 * create_recursive_compset(+Ids,+Cond,+Type,+Infos,-RecId,-TCompSet)
3187 * creates a recursive comprehension set:
3188 * Ids is the list of the introduced typed identifiers
3189 * Cond is the condition (a typed predicate)
3190 * Infos are additional informations for the comprehension set syntax element
3191 * RecId is the identifier (untyped, an atom) that can be used in Cond to refer to the
3192 * comprehension set recursively. Usually RecId is used in Cond as a variable
3193 * TCompSet is the generated recursive comprehension set, the recursion parameter is introduced
3194 * by a recusive(Id,CompSet) syntax element
3195 */
3196 create_recursive_compset(Ids,Cond,Type,Infos,RecId,TCompSet) :-
3197 unique_id("recursive.",RecId),
3198 add_symbolic_annotation(Infos,RInfos),
3199 create_texpr(comprehension_set(Ids,Cond),Type,RInfos,TCompSet1),
3200 create_typed_id(RecId,Type,TRecId),
3201 create_texpr(recursive_let(TRecId,TCompSet1),Type,[],TCompSet).
3202
3203 unique_typed_id(Prefix,Type,TId) :-
3204 unique_id(Prefix,Id),
3205 create_typed_id(Id,Type,TId).
3206
3207
3208 mark_bexpr_as_symbolic(b(E,T,I),b(E2,T,RI)) :-
3209 add_symbolic_annotation(I,RI),
3210 mark_aux(E,E2).
3211 mark_aux(union(A,B),R) :- !, R=union(SA,SB),
3212 mark_bexpr_as_symbolic(A,SA), mark_bexpr_as_symbolic(B,SB).
3213 % union is currently the only operator that is kept symbolically
3214 mark_aux(A,A).
3215
3216 add_symbolic_annotation([H|I],R) :- H == prob_annotation('SYMBOLIC'),!, R=[H|I].
3217 add_symbolic_annotation(I,R) :- !, R=[prob_annotation('SYMBOLIC')|I].
3218
3219 % identifier_sub_ast(+TExpr,+Identifier,-SubPosition):
3220 % Find occurences of an identifier "Identifier" in an expression "TExpr"
3221 % Returns a list of positions (beginning with 0) that describes the position of a sub-expression
3222 % that contains all occurrences of Identifier in TExpr.
3223 % E.g. [1,0,1] means "second sub-expression of TExpr, then the first sub-expression of that,
3224 % then the second sub-expression of that".
3225 % When an identifier has multiple occurences, the position of the sub-expression is returned
3226 % where all occurences of it are located.
3227 % If the identifier is not found, the call fails.
3228 % Sub-expressions are meant like the ones syntaxtraversion or syntaxtransformation return.
3229 identifier_sub_ast(TExpr,Identifier,SubPosition) :-
3230 syntaxtraversion(TExpr,Expr,_Type,_Infos,AllSubs,Names),
3231 identifier_sub_ast_aux(Expr,AllSubs,Names,Identifier,SubPosition).
3232 identifier_sub_ast_aux(identifier(Identifier),[],[],Identifier,[]) :- !.
3233 identifier_sub_ast_aux(_Expr,AllSubs,Names,Identifier,SubPosition) :-
3234 get_texpr_id(TId,Identifier),nonmember(TId,Names),
3235 % For each sub-expression E in the list AllSubs create a term Pos-E
3236 % where Pos is E's position (starting with 0) in AllSubs
3237 foldl(annotate_pos,AllSubs,AllAnnotatedSubs,0,_),
3238 % Introduced identifiers occur alsa as sub-expressions, remove those
3239 foldl(select_sub,Names,AllAnnotatedSubs,RealAnnSubs),
3240 convlist_max(identifier_sub_ast_aux2(Identifier),2,RealAnnSubs,SubPositions), % find at most 2 sols
3241 ( SubPositions = [SubPosition] -> true
3242 ; SubPositions = [_,_|_] -> % More then one occurrences - make this the found node
3243 SubPosition = []).
3244 identifier_sub_ast_aux2(Identifier,Pos-TExpr,[Pos|SubPosition]) :-
3245 identifier_sub_ast(TExpr,Identifier,SubPosition).
3246 annotate_pos(TExpr,I-TExpr,I,I2) :- I2 is I+1.
3247 select_sub(Name,AnnotatedSubs,Result) :-
3248 selectchk(_Pos-Name,AnnotatedSubs,Result).
3249
3250
3251
3252 % exchange_ast_position(+SubPosition,+OldTExpr,-OldInner,+NewInner,-NewTExpr):
3253 % exchanges a sub-expression in the expression "OldTExpr".
3254 % SubPosition is a list of positions like identifier_sub_ast/3 returns it.
3255 % OldInner is the sub-expression found in OldTExpr.
3256 % NewInner is the new sub-expression.
3257 % NewTExpr is the new expression that originates from replacing OldInner by NewInner.
3258 exchange_ast_position([],Old,Old,New,New).
3259 exchange_ast_position([Pos|RestPos],OldTExpr,OldInner,NewInner,NewTExpr) :-
3260 remove_bt_and_used_ids(OldTExpr,OldExpr,NewExpr,NewTExpr), % also invalidates used_ids info
3261 syntaxtransformation(OldExpr,Subs,_Names,NSubs,NewExpr),
3262 nth0(Pos,Subs, OldSelected,Rest),
3263 nth0(Pos,NSubs,NewSelected,Rest),
3264 exchange_ast_position(RestPos,OldSelected,OldInner,NewInner,NewSelected).
3265
3266
3267 % -----------------------
3268 % utility to expand / inline all let expressions and let predicates:
3269 % useful for tools that cannot handle the lets
3270
3271 expand_all_lets(Expr,NewExpr) :-
3272 transform_bexpr(tl_expand_lets,Expr,NewExpr).
3273
3274 tl_expand_lets(b(E,_,_),Res) :- tl_expand_lets2(E,Res).
3275 tl_expand_lets2(let_expression(Ids,Exprs,Body),NewBody) :- % expand LET expression
3276 replace_ids_by_exprs(Body,Ids,Exprs,NewBody).
3277 tl_expand_lets2(let_predicate(Ids,Exprs,Body),NewBody) :- % expand LET predicate
3278 replace_ids_by_exprs(Body,Ids,Exprs,NewBody).
3279
3280 % -----------------------
3281
3282 :- public check_used_ids/2.
3283 % a simple checker, only checks used_ids info fields for entire typed expression:
3284 check_used_ids(TExpr,PP) :- %format('CHECK AST for ~w~n',[PP]),
3285 map_over_typed_bexpr(check_used_ids_texpr_fail(PP),TExpr).
3286 check_used_ids(_,_).
3287 check_used_ids_texpr_fail(PP,E) :- check_used_ids_texpr(PP,E),!,fail.
3288 check_used_ids_texpr(PP,b(P,T,I)) :- member(used_ids(UIds1),I),!,
3289 (find_identifier_uses(b(P,T,I),[],UIds2) -> true
3290 ; add_internal_error('find_identifier_uses failed',PP),fail),
3291 (UIds1==UIds2 -> true
3292 ; format('*** Wrong used_ids Info (~w)!!~n Used_ids: ~w~n Comp_ids: ~w~n',[PP,UIds1,UIds2]),
3293 translate:print_bexpr(b(P,T,I)),nl,
3294 add_error(check_used_ids,'Wrong used_ids: ',PP,I)
3295 ).
3296 check_used_ids_texpr(_,_).
3297
3298 % repair any broken used_ids info in typed expression TExpr and re-compute used_ids if necessary
3299 % PP is a program point, will be reported in case of an error
3300 repair_used_ids(PP,TExpr,Res) :-
3301 (transform_bexpr(bsyntaxtree:repair_used_ids_info(PP),TExpr,NewTExpr) -> Res=NewTExpr
3302 ; add_internal_error('Repairing used_ids failed:',PP),
3303 Res=TExpr).
3304
3305 % we could also simply call recompute_used_ids_inf; but it would not generate any messages
3306 repair_used_ids_info(PP,b(P,T,I),b(P,T,NI)) :- %functor(P,FF,_), print(repair(FF)),nl,
3307 select(used_ids(OldUsed),I,I2),!,
3308 (find_identifier_uses(b(P,T,I),[],NewUsed)
3309 -> (NewUsed=OldUsed -> NI=I
3310 ; NI = [used_ids(NewUsed)|I2],
3311 add_message(repair_used_ids,'Updating used_ids for: ',b(P,T,I),I2)
3312 )
3313 ; add_internal_error('find_identifier_uses failed',PP),
3314 NI=I
3315 ).
3316 repair_used_ids_info(PP,b(P,T,I),b(P,T,NI)) :-
3317 requires_used_ids(P),
3318 (find_identifier_uses(b(P,T,I),[],NewUsed) -> true
3319 ; add_internal_error('find_identifier_uses failed',PP),fail
3320 ),
3321 !,
3322 NI=[used_ids(NewUsed)|I].
3323 repair_used_ids_info(_,B,B).
3324
3325 requires_used_ids(exists(_,_)).
3326 requires_used_ids(forall(_,_,_)).
3327
3328 % a simple checker to see if an AST is well-formed:
3329 % can be tested e.g. as follows: b_get_invariant_from_machine(I), check_ast(I).
3330 % called in prob_safe_mode by clean_up_section
3331
3332 check_ast(TE) :- check_ast(false,TE).
3333 check_ast(AllowVars,TExpr) :- %nl,print('CHECK AST'),nl,
3334 map_over_typed_bexpr(check_ast_texpr(AllowVars),TExpr).
3335 check_ast(_,_).
3336
3337 :- use_module(typing_tools,[valid_ground_type/1]).
3338 %check_ast_texpr(X) :- print(check(X)),nl,fail.
3339 check_ast_texpr(AllowVars,AST) :- AST = b(E,Type,Infos),
3340 (debug:debug_level_active_for(9) -> write(' check_ast: '),print_bexpr(AST), write(' :: '), write(Type), nl ; true),
3341 (check_expr(E,Type,Infos) -> true
3342 ; add_error(check_ast_texpr,'Invalid Expr: ', AST) %, trace, check_expr(E,Type,Infos)
3343 ),
3344 (check_type(Type,AllowVars) -> true
3345 ; add_error(check_ast_texpr,'Invalid Type for: ',AST,Infos)),
3346 safe_functor(E,F),
3347 check_ast_typing(E,Type,Infos),
3348 (check_infos(Infos,F) -> true ; add_error(check_ast_texpr,'Invalid Infos: ',AST)),
3349 check_special_rules(E,Type,Infos),
3350 fail. % to force backtracking in map_over_typed_bexpr
3351
3352
3353 check_special_rules(operation_call_in_expr(Operation,_),_,OInfos) :- !,
3354 get_texpr_info(Operation,Info), % reads info important for used_ids computation
3355 (memberchk(reads(_V),Info) -> true
3356 ; add_error(check_ast_texpr,'Missing reads info: ',Operation,OInfos)).
3357
3358
3359 safe_functor(V,R) :- var(V),!,R='$VAR'.
3360 safe_functor(E,F/N) :- functor(E,F,N).
3361
3362 % check whether the type term is ok
3363 check_type(X,AllowVars) :- var(X),!,
3364 (AllowVars==true -> true ; add_error(check_type,'Variable type: ',X),fail).
3365 check_type(pred,_) :- !.
3366 check_type(subst,_) :- !.
3367 check_type(op(Paras,Returns),AllowVars) :- !,
3368 maplist(check_normal_type(AllowVars),Paras),
3369 maplist(check_normal_type(AllowVars),Returns).
3370 check_type(T,AllowVars) :- check_normal_type(AllowVars,T).
3371
3372 check_normal_type(AllowVars,T) :-
3373 (AllowVars \== true -> valid_ground_type(T)
3374 ; ground(T) -> valid_ground_type(T)
3375 ; true). % TO DO: call valid_ground_type but pass AllowVars
3376
3377 :- use_module(probsrc(btypechecker), [lookup_type_for_expr/2, unify_types_werrors/4]).
3378 % check whether type is compatible with operators
3379 check_ast_typing(member(A,B),Type,Pos) :- !,
3380 get_texpr_type(B,TB), check_set_type(TB,member,Pos),
3381 check_type(Type,pred,member),
3382 get_texpr_type(A,TA),
3383 unify_types_werrors(set(TA),TB,Pos,member).
3384 check_ast_typing(not_equal(A,B),Type,Pos) :- !, check_ast_typing(equal(A,B),Type,Pos).
3385 check_ast_typing(equal(A,B),Type,Pos) :- !,
3386 get_texpr_type(B,TB),
3387 get_texpr_type(A,TA),
3388 unify_types_werrors(TA,TB,Pos,'='),
3389 (non_value_type(TA)
3390 -> add_error(check_ast_typing,'Binary predicate has to have values as arguments:',TA,Pos)
3391 ; Type=pred -> true
3392 ; add_error(check_ast_typing,'Illegal type for binary predicate:',Type,Pos)
3393 ).
3394 check_ast_typing(greater_equal(A,B),Type,_) :- !,
3395 get_texpr_type(A,TA),check_type(TA,integer,greater_equal),
3396 get_texpr_type(B,TB),check_type(TB,integer,greater_equal), check_type(Type,pred,member).
3397 check_ast_typing(Expr,Type,Pos) :-
3398 syntaxtransformation(Expr,Subs,Names,NSubs,NewExpr),
3399 check_names(Names,Pos),
3400 (lookup_type(NewExpr,T) -> true
3401 ; add_warning(check_ast_typing,'Unable to lookup type for: ',NewExpr),
3402 fail
3403 ),
3404 !,
3405 (unify_types_werrors(Type,T,Pos,'check_ast')
3406 -> maplist(check_sub_type(Expr,Pos),Subs,NSubs)
3407 ; add_error(check_ast_typing,'Type mismatch for expression:',Expr,Pos)
3408 ).
3409 check_ast_typing(_,subst,_) :- !. % ignore subst for the moment
3410 check_ast_typing(operation(_TName,_Res,_Params,_TBody),_,_) :- !. % ignore operations for the moment
3411 check_ast_typing(Expr,_,Pos) :-
3412 syntaxtransformation(Expr,_,_Names,_,_NewExpr),!,
3413 add_message(check_ast_typing,'Cannot lookup type for expression: ',Expr,Pos).
3414 check_ast_typing(Expr,_,Pos) :-
3415 add_message(check_ast_typing,'No applicable type rule for expression: ',Expr,Pos).
3416
3417 non_value_type(X) :- var(X),!,fail.
3418 non_value_type(pred).
3419 non_value_type(subst).
3420 non_value_type(op(_)).
3421
3422
3423 check_names([],_).
3424 check_names([H|T],Pos) :-
3425 (member(H,T) -> add_error(check_ast_name,'Duplicate name:',H,Pos) ; check_names(T,Pos)).
3426
3427 check_sub_type(OuterExpr,Pos,Arg,Type) :- get_texpr_type(Arg,T),!,
3428 (unify_types_werrors(Type,T,Pos,'check_sub_type') -> true
3429 ; add_error(check_ast_typing,'Type mismatch for sub-expression:',Arg,Pos),
3430 write('Outer expression: '),translate:print_bexpr(OuterExpr),nl,
3431 write('Outer type: '),write(Type),nl,
3432 write('Arg type: '),write(T),nl,print(type(T)),nl, tools_printing:print_term_summary(Arg),nl,trace
3433 ).
3434 check_sub_type(_,Pos,Arg,_) :-
3435 add_error(check_ast_typing,'Cannot extract type: ',Arg,Pos).
3436
3437 lookup_type(identifier(_),_) :- !. % ignore typing issues for identifiers
3438 lookup_type(Expr,Type) :- lookup_type_for_expr(Expr,Type).
3439
3440 check_set_type(Var,_,_) :- var(Var),!.
3441 check_set_type(set(_),_,_) :- !.
3442 check_set_type(seq(_),_,_) :- !.
3443 check_set_type(Type,Func,Pos) :- add_error(check_ast_typing,'Invalid type for operator: ',Func:Type,Pos).
3444
3445 check_type(Type,Type,_) :- !.
3446 check_type(Type,_,Func) :- add_error(check_ast_typing,'Unexpected type for operator: ',Func:Type).
3447
3448 check_infos(X,F) :- var(X),!, add_error(check_infos,'Info field list not terminated: ',F:X),fail.
3449 check_infos([],_).
3450 check_infos([H|_],F) :- \+ ground(H),!, add_error(check_infos,'Info field not ground: ',F:H),fail.
3451 check_infos([[H|T]|_],F) :- !, add_error(check_infos,'Info field contains nested list: ',F:[H|T]),fail.
3452 check_infos([cse_used_ids(H)|T],F) :- member(cse_used_ids(H2),T),!,
3453 add_error(check_infos,'Multiple cse_used_ids entries: ',F:[H,H2]),fail.
3454 check_infos([used_ids(H)|T],F) :- member(used_ids(H2),T),!,
3455 add_error(check_infos,'Multiple used_ids entries: ',F:[H,H2]),fail.
3456 check_infos([nodeid(N1)|T],F) :- member(nodeid(N2),T),!,
3457 add_error(check_infos,'Multiple nodeid entries: ',F:[N1,N2],[nodeid(N1)]),fail.
3458 check_infos([removed_typing|T],F) :- member(removed_typing,T),!,
3459 add_error(check_infos,'Multiple removed_typing entries: ',F,T),fail.
3460 check_infos([_|T],F) :- check_infos(T,F).
3461
3462 check_expr(Expr,Type,Infos) :- nonmember(contains_wd_condition,Infos),
3463 sub_expression_contains_wd_condition(Expr,Sub),
3464 TE = b(Expr,Type,Infos),
3465 (Type = subst
3466 -> fail % AST cleanup is not called for substitutions; WD-info not available for substitutions at the moment
3467 ; translate_bexpression(TE,PS)),
3468 functor(Expr,Functor,_),
3469 functor(Sub,SubFunctor,_),
3470 tools:ajoin(['Node for AST node ',Functor,' does not contain WD info from Subexpression ',SubFunctor,' :'],Msg),
3471 add_warning(check_expr,Msg,PS,TE).
3472 % well_def_analyser:nested_print_wd_bexpr(TE),nl.
3473 % TODO: check when we have an unnecessary WD condition
3474 check_expr(Expr,Type,Infos) :- nonmember(contains_wd_condition,Infos),
3475 always_not_wd_top(Expr),
3476 add_warning(check_expr,'AST is not well-defined but does not contain WD info: ',b(Expr,Type,Infos),Infos).
3477 check_expr(member(LHS,RHS),Type,Infos) :- is_just_type(RHS),
3478 get_preference(optimize_ast,true),
3479 !,
3480 TE = b(member(LHS,RHS),Type,Infos),
3481 translate:translate_bexpression(TE,PS),
3482 add_warning(check_expr,'AST contains redundant typing predicate: ',PS,TE).
3483 check_expr(identifier(ID),_,_) :- illegal_id(ID),!,
3484 add_error(check_infos,'Illegal identifier: ', identifier(ID)).
3485 check_expr(lazy_lookup_expr(ID),_,_) :- illegal_id(ID),!,
3486 add_error(check_infos,'Illegal identifier: ', lazy_lookup_expr(ID)).
3487 check_expr(lazy_lookup_pred(ID),_,_) :- illegal_id(ID),!,
3488 add_error(check_infos,'Illegal identifier: ', lazy_lookup_pred(ID)).
3489 check_expr(exists(Parameters,Condition),pred,Infos) :- !,
3490 check_used_ids(exists,Parameters,Condition,Infos,_Used).
3491 check_expr(forall(Parameters,LHS,RHS),pred,Infos) :- !,
3492 create_implication(LHS,RHS,Condition),
3493 check_used_ids(forall,Parameters,Condition,Infos,_Used). %
3494 check_expr(value(V),Type,_) :- !, check_bvalue(V,Type).
3495 check_expr(_,_,_).
3496
3497 % will check all used_ids fields (not just for exists and forall)
3498 :- public check_used_ids_in_ast/1.
3499 check_used_ids_in_ast(closure(_,_,TExpr)) :- !, (map_over_typed_bexpr(check_used_ids_aux,TExpr) ; true).
3500 check_used_ids_in_ast(TExpr) :- map_over_typed_bexpr(check_used_ids_aux,TExpr).
3501 check_used_ids_in_ast(_).
3502
3503 check_used_ids_aux(AST) :- AST = b(_,_,Infos),
3504 member(used_ids(_),Infos),!,
3505 find_identifier_uses_if_necessary(AST,[],_), % will perform check
3506 fail.
3507
3508 % --------------------
3509
3510 :- use_module(specfile,[eventb_mode/0, z_or_tla_minor_mode/0]).
3511 % check if an expression is definitely not WD; looking at the top-level operator only
3512 always_not_wd_top(function(X,_)) :- definitely_empty_set(X). % TODO: detect a few more cases, e.g., arg not in dom
3513 always_not_wd_top(power_of(X,Y)) :- (get_integer(Y,VY), VY < 0 -> true
3514 ; eventb_mode, get_integer(X,VX), VX < 0).
3515 always_not_wd_top(div(_,Val)) :- get_integer(Val,VV), VV==0.
3516 always_not_wd_top(modulo(X,Y)) :-
3517 (get_integer(Y,VY), VY=<0
3518 -> true % there seems to be a def for Z in Z Live, cf modulo2
3519 ; get_integer(X,VX), VX<0, \+ z_or_tla_minor_mode).
3520 always_not_wd_top(min(X)) :- definitely_empty_set(X).
3521 always_not_wd_top(max(X)) :- definitely_empty_set(X).
3522 always_not_wd_top(size(X)) :- definitely_not_sequence(X). % TODO: detect infinite sets; also for card(_)
3523 always_not_wd_top(first(X)) :- definitely_not_non_empty_sequence(X).
3524 always_not_wd_top(front(X)) :- definitely_not_non_empty_sequence(X).
3525 always_not_wd_top(last(X)) :- definitely_not_non_empty_sequence(X).
3526 always_not_wd_top(tail(X)) :- definitely_not_non_empty_sequence(X).
3527 always_not_wd_top(general_intersection(X)) :- definitely_empty_set(X).
3528
3529 definitely_not_non_empty_sequence(X) :-
3530 (definitely_empty_set(X) -> true ; definitely_not_sequence(X)).
3531
3532 :- use_module(avl_tools,[avl_min_pair/3]).
3533 definitely_not_sequence(b(value(A),_,_)) :- nonvar(A), A=avl_set(AVL),
3534 avl_min_pair(AVL,int(StartIndex),_), StartIndex \= 1.
3535 % TODO: treat set_extension
3536
3537 :- use_module(b_ast_cleanup,[check_used_ids_info/4]).
3538 check_used_ids(Quantifier,Parameters,Condition,Infos,Used) :-
3539 select(used_ids(Used),Infos,Rest)
3540 -> check_used_ids_info(Parameters,Condition,Used,Quantifier), %% comment in to check used_ids field
3541 (member(used_ids(_),Rest)
3542 -> add_internal_error('Multiple used_ids info fields:',Parameters:Infos) ; true)
3543 ;
3544 add_internal_error(
3545 'Expected information of used identifiers information',Quantifier:Parameters:Infos).
3546
3547 illegal_id(ID) :- var(ID),!.
3548 illegal_id(op(ID)) :- !, \+ atom(ID).
3549 illegal_id(ID) :- \+ atom(ID).
3550
3551 :- use_module(btypechecker, [unify_types_strict/2, couplise_list/2]).
3552 :- use_module(avl_tools,[check_is_non_empty_avl/1]).
3553 % TO DO: we could check type more
3554 check_bvalue(V,_) :- var(V),!.
3555 check_bvalue(avl_set(A),Type) :- !, unify_types_strict(Type,set(_)),
3556 check_is_non_empty_avl(A).
3557 check_bvalue(closure(_,T,B),Type) :- !,
3558 couplise_list(T,CT), unify_types_strict(set(CT),Type),
3559 check_ast(B).
3560 check_bvalue(_,_).
3561
3562 % -----------------------
3563
3564
3565 indent_ws(X) :- X<1,!.
3566 indent_ws(X) :- print(' '), X1 is X-1, indent_ws(X1).
3567
3568 print_ast_td(b(E,T,I),Level,L1) :-
3569 indent_ws(Level),
3570 (E=identifier(_)
3571 -> format('~w (~w) -> ~w~n',[E,T,I])
3572 ; functor(E,F,N),
3573 format('~w/~w (~w) -> ~w~n',[F,N,T,I])
3574 ),
3575 L1 is Level+1.
3576 print_ast(TExpr) :-
3577 (map_over_typed_bexpr_top_down_acc(print_ast_td,TExpr,0),fail ; true).
3578
3579 % ---------------------
3580
3581 :- dynamic count_id_usage/2.
3582 single_usage_id_count(Expr) :- uses_an_identifier(Expr,Id),
3583 retract(count_id_usage(Id,Count)),
3584 !,
3585 Count=0,
3586 C1 is Count+1,
3587 assertz(count_id_usage(Id,C1)).
3588 single_usage_id_count(_).
3589
3590 % check if an identifier is used at most once
3591 single_usage_identifier(ID,ExprOrPredicates,Count) :-
3592 retractall(count_id_usage(_,_)),
3593 assertz(count_id_usage(ID,0)),
3594 % TO DO: take care of naming; do not count occurences when we enter scope defining ID
3595 maplist(single_usage_cnt,ExprOrPredicates),
3596 retract(count_id_usage(ID,Count)).
3597
3598 single_usage_cnt(ExprOrPredicate) :- map_over_full_bexpr_no_fail(single_usage_id_count,ExprOrPredicate).
3599
3600 gen_fresh_id_if_necessary(Default,Expr,FreshID) :-
3601 occurs_in_expr(Default,Expr),!,
3602 gensym('__FRESH_ID__',FreshID). % assumes _Fresh_XXX not used
3603 gen_fresh_id_if_necessary(Default,_,Default).
3604
3605 %% rewrite_if_then_else_expr_to_b(IfThenElseExpr, NExpr).
3606 % Rewrite if-then-else expr to B as understood by Atelier-B.
3607 % {d,x| d:BOOL & If => x=Then & not(if) => x=Else}(TRUE)
3608 rewrite_if_then_else_expr_to_b(if_then_else(If,Then,Else), NExpr) :-
3609 get_texpr_type(Then,Type),
3610 ARG = b(boolean_true,boolean,[]), AT=boolean, % we could use unit type or BOOL here
3611 gen_fresh_id_if_necessary('_zzzz_unary',b(if_then_else(If,Then,Else),Type,[]),AID1),
3612 gen_fresh_id_if_necessary('_zzzz_binary',b(if_then_else(If,Then,Else),Type,[]),AID2),
3613 safe_create_texpr(identifier(AID1), AT, [], Id1), % a dummy argument
3614 safe_create_texpr(identifier(AID2), Type, [], Id2), % The result
3615 safe_create_texpr(equal(Id2,Then), pred, [], Eq1),
3616 safe_create_texpr(equal(Id2,Else), pred, [], Eq2),
3617 safe_create_texpr(implication(If,Eq1), pred, [], Pred1),
3618 safe_create_texpr(negation(If), pred, [], NIf),
3619 safe_create_texpr(implication(NIf,Eq2), pred, [], Pred2),
3620 safe_create_texpr(conjunct(Pred1,Pred2), pred, [], Pred),
3621 safe_create_texpr(comprehension_set([Id1,Id2],Pred), set(couple(AT,Type)), [], FUN),
3622 NExpr = function(FUN,ARG).
3623
3624
3625 % --------------------
3626
3627 % apply normalisation rules from Atlier-B PP/ML provers
3628 % see chapter 3 of Atelier-B prover manual
3629
3630 normalise_bexpr_for_ml(TExpr,Res) :-
3631 transform_bexpr(normalise_bexpr,TExpr,Res).
3632
3633 normalise_bexpr(b(E,T,I),b(E2,T,I)) :- norm2(E,E2),!.
3634
3635 norm2(equivalence(A,B),conjunct(TIMP1,TIMP2)) :- !,
3636 safe_create_texpr(implication(A,B),pred,TIMP1),
3637 safe_create_texpr(implication(B,A),pred,TIMP2).
3638 norm2(subset_strict(A,B),conjunct(TMEM,TNEQ)) :- !,
3639 norm2(subset(A,B),MEM), safe_create_texpr(MEM,pred,TMEM),
3640 safe_create_not_equal(A,B,TNEQ).
3641 norm2(subset(A,B),member(A,PowB)) :- !, % A <: B <===> A:POW(B)
3642 get_texpr_type(A,TA),
3643 safe_create_texpr(pow_subset(B),TA,PowB).
3644 norm2(not_equal(A,B),negation(TEQ)) :- !,
3645 safe_create_texpr(equal(A,B),pred,TEQ).
3646 norm2(not_member(A,B),negation(TMEM)) :- !,
3647 safe_create_texpr(member(A,B),pred,TMEM).
3648 norm2(not_subset(A,B),negation(TMEM)) :- !,
3649 norm2(subset(A,B),MEM),safe_create_texpr(MEM,pred,TMEM).
3650 norm2(not_subset_strict(A,B),implication(TMEM,TEQ)) :- !, % A /<< : B <===> A:POW(B) => A=B
3651 norm2(subset(A,B),MEM),safe_create_texpr(MEM,pred,TMEM),
3652 safe_create_texpr(equal(A,B),pred,TEQ).
3653 norm2(POW1,set_subtraction(TPOW,TSEMPTY)) :- not_empty_pow(POW1,A,POW), !,
3654 % POW1(A) <===> POW(A) - {{}}, FIN1(A) <===> FIN(A) - {{}}, ...
3655 safe_create_texpr(POW,pred,TPOW),
3656 get_texpr_type(A,TA), TEMPTY = b(empty_set,TA,[]),
3657 safe_create_texpr(set_extension([TEMPTY]),set(TA),TSEMPTY).
3658 norm2(member(A,b(integer_set('NATURAL'),_,_)),conjunct(TMEM,TLEQ)) :- !, % A <: NATURAL <===> A:INTEGER & 0 <= A
3659 INTEGER = b(integer_set('INTEGER'),set(integer),[]),
3660 safe_create_texpr(member(A,INTEGER),pred,TMEM),
3661 Zero = b(integer(0),integer,[]),
3662 safe_create_texpr(less_equal(Zero,A),pred,TLEQ).
3663 norm2(set_extension(List),Union) :- List = [H|T], T=[_|_], !, % {A,B} <===> {A} \/ {B}
3664 get_texpr_type(H,Type),
3665 set_extension_to_union(H,T,set(Type),b(Union,_,_)).
3666 norm2(greater_equal(A,B),less_equal(B,A)) :- !.
3667 norm2(greater(A,B),less_equal(B1,A)) :- !, plus1(B,B1).
3668 norm2(less(A,B),less_equal(A,B1)) :- !, minus1(B,B1). % the normalisation rule in chapter 3 is actually false
3669 norm2(integer_set(NAT1),set_subtraction(TNAT,TSZero)) :- nat1(NAT1,NAT), !, % NATURAL1 <===> NATURAL - {0}
3670 TNAT = b(integer_set(NAT),set(integer),[]),
3671 set_with_zero(TSZero).
3672 norm2(empty_sequence,empty_set) :- !.
3673 norm2(perm(A),intersection(ISEQ,PSURJ)) :- !, % perm(A) <===> iseq(A) /\ (NATURAL-{0} +->> A)
3674 get_texpr_type(A,TA),
3675 safe_create_texpr(iseq(A),set(seq(TA)),ISEQ),
3676 set_with_zero(TSZero),
3677 NATURAL = b(integer_set('NATURAL'),set(integer),[]),
3678 safe_create_texpr(set_subtraction(NATURAL,TSZero),set(integer),DOM),
3679 safe_create_texpr(partial_surjection(DOM,A),set(seq(TA)),PSURJ).
3680 % TODO: total_relation, if_then_else, ...?
3681
3682 set_with_zero(TSZero) :- % {0}
3683 TZero = b(integer(0),TA,[]),
3684 safe_create_texpr(set_extension([TZero]),set(TA),TSZero).
3685
3686 % TODO: more intelligent versions like x-1 ==> x ...
3687 plus1(A,Plus1) :- One = b(integer(1),integer,[]),
3688 safe_create_texpr(add(A,One),integer,Plus1).
3689 minus1(A,Plus1) :- One = b(integer(1),integer,[]),
3690 safe_create_texpr(minus(A,One),integer,Plus1).
3691
3692 not_empty_pow(pow1_subset(A),A,pow_subset(A)).
3693 not_empty_pow(fin1_subset(A),A,fin_subset(A)).
3694 not_empty_pow(seq1(A),A,seq(A)).
3695 not_empty_pow(iseq1(A),A,iseq(A)).
3696
3697 nat1('NATURAL1','NATURAL').
3698 nat1('NAT1','NAT').
3699
3700 safe_create_not_equal(A,B,TNEQ) :-
3701 safe_create_texpr(equal(A,B),pred,TEQ),
3702 safe_create_texpr(negation(TEQ),pred,TNEQ).
3703
3704 set_extension_to_union(H,[],Type,Res) :- !,
3705 safe_create_texpr(set_extension([H]),Type,Res).
3706 set_extension_to_union(H,[H2|T],Type,Res) :-
3707 safe_create_texpr(set_extension([H]),Type,TH),
3708 set_extension_to_union(H2,T,Type,TUnion),
3709 safe_create_texpr(union(TH,TUnion),Type,Res).