1/* Part of Ciao Prolog compatibility library 2 3 Author: Jan Wielemaker, Edison Mera 4 E-mail: J.Wielemaker@uva.nl, efmera@gmail.com 5 WWW: http://www.edisonm.com 6 Copyright (C): 2009, University of Amsterdam and 7 2013, Process Design Center, Breda, The Netherlands. 8 9 This program is free software; you can redistribute it and/or 10 modify it under the terms of the GNU General Public License 11 as published by the Free Software Foundation; either version 2 12 of the License, or (at your option) any later version. 13 14 This program is distributed in the hope that it will be useful, 15 but WITHOUT ANY WARRANTY; without even the implied warranty of 16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 GNU General Public License for more details. 18 19 You should have received a copy of the GNU General Public 20 License along with this library; if not, write to the Free Software 21 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 22 23 As a special exception, if you link this library with other files, 24 compiled with a Free Software compiler, to produce an executable, this 25 library does not by itself cause the resulting executable to be covered 26 by the GNU General Public License. This exception does not however 27 invalidate any other reasons why the executable file might be covered by 28 the GNU General Public License. 29*/ 30 31:- module(ciao, 32 [ 33 '$ciao_meta'/2, 34 '$ciao_meta'/3, 35 '$ciao_meta'/4, 36 '$ciao_meta'/5, 37 '$ciao_meta'/6, 38 '$ciao_meta'/7, 39 '$ciao_meta'/8, 40 op(1150, fx, data) 41 ]). 42:- use_module(library(error)). 43:- use_module(library(apply)). 44:- use_module(library(debug)).

Ciao Prolog compatibility module

This module sets up support for loading Ciao Prolog modules that start with a :- module(Name, Exports, Packages) directive. Upon encountering this directive, it is rewritten into a SWI-Prolog module declaration, followed by a series of directives to setup Ciao compatibility.

Typical usage for loading Ciao code is:

:- use_module(library(dialect/ciao)).

To be done: - Create much more of the Ciao infrastructure. */

62:- multifile 63 system:goal_expansion/2, 64 system:term_expansion/2, 65 ciao_trans/4, 66 ciao_trans_db/5, 67 ciao_goal_expansion/2, 68 ciao_term_expansion/2, 69 user:file_search_path/2. 70 71 72 /******************************* 73 * PATHS * 74 *******************************/ 75 76user:file_search_path(engine, library(dialect/ciao/engine)). 77 78 79 /******************************* 80 * MODULES & DECLARATIONS * 81 *******************************/ 82 83:- create_prolog_flag(multi_arity_warnings, off, [type(atom)]). 84:- create_prolog_flag(discontiguous_warnings, on, [type(atom)]). 85 86:- multifile 87 declaration/2, % +Head,+Module 88 declaration_hook/2. % +Head,-Exp 89 90:- dynamic 91 lock_expansion/0, 92 old_flag/3. 93 94compilation_module(CM) :- % Kludge: compilation module must be 95 % imported in a separated module and 96 % its methods invoked from there --EMM 97 '$current_source_module'(M), 98 compilation_module(M, CM). 99 100compilation_module(M, CM) :- 101 atom_concat(M, '$ciao', CM). 102 % TODO: missing support for directives 103 % add_clause_translation/1 and 104 % add_term_translation/1 --EMM 105 106call_lock(Goal) :- 107 setup_call_cleanup((\+ lock_expansion,assertz(lock_expansion)), 108 Goal, retract(lock_expansion)). 109 110system:goal_expansion(In, Out) :- 111 prolog_load_context(dialect, ciao), 112 compilation_module(CM), 113 ciao_trans(CM, goal, In, Out1), % Ciao Goal Translations 114 ( In == end_of_file % end_of_file Ciao hook 115 -> Out = true 116 ; Out = Out1 117 ). 118system:goal_expansion(In, Out) :- 119 prolog_load_context(dialect, ciao), 120 ciao_goal_expansion(In, Out). % SWI Compatibility issues 121 122system:term_expansion(In, Out) :- 123 prolog_load_context(dialect, ciao), 124 compilation_module(CM), 125 call_lock((ciao_trans(CM, sentence, In, Out1), % Sentence Translations 126 '$expand':expand_terms(call_term_expansion([system-[term_expansion/2]]), 127 Out1, _, Out2, _) % Remaining 128 )), 129 call_eof_goal_hook(In, Out2, Out). 130system:term_expansion(In, Out) :- 131 prolog_load_context(dialect, ciao), 132 ciao_term_expansion(In, Out). 133 134call_eof_goal_hook(In, Out2, Out) :- 135 '$current_source_module'(M), 136 ( In == end_of_file, 137 module_property(M, file(File)), 138 prolog_load_context(file, File) % This is the main file 139 -> ( is_list(Out2) 140 -> append(Out2, [(:- end_of_file)], Out) 141 ; Out = [Out2, (:- end_of_file)] 142 ) % (:- end_of_file) is a hook for the goal expansion 143 ; Out = Out2 144 ). 145 146package_file(F, P) :- 147 ( atom(F) -> P = library(F) 148 ; functor(F, _, 1) -> P = F 149 ). 150 151package_directive(Package, Directive) :- 152 expand_term((:- use_package(Package)), Directive). 153 154ciao_term_expansion((:- module(Name, Public, Packages)), 155 [ (:- module(Name, Public)), 156 (:- style_check(-singleton)), 157 (:- expects_dialect(ciao)), 158 (:- use_module(engine(basic_props))), 159 (:- use_module(engine(io_aux))), 160 (:- use_module(engine(exceptions))) 161 | Directives 162 ]) :- 163 maplist(package_directive, Packages, Directives). 164 165map_ciaoname_rec(Ciao, Path, Path/Ciao) :- atom(Ciao), !. 166map_ciaoname_rec(Ciao0, Path, SWI) :- 167 Ciao0 =.. [F, Ciao], 168 map_ciaoname_rec(Ciao, Path/F, SWI). 169 170map_ciaoname_(Path, Path) :- atom(Path), !. 171map_ciaoname_(Ciao0, SWI) :- 172 Ciao0 =.. [F, Ciao], 173 map_ciaoname_rec(Ciao, F, SWI). 174 175map_ciaoname(CiaoName, SWIName) :- 176 CiaoName =.. [F, C], 177 SWIName =.. [F, S], 178 map_ciaoname_(C, S). 179 180ciao_term_expansion((:- use_package(CiaoPack)), 181 (:- include(SWIName))) :- 182 package_file(CiaoPack, CiaoName), 183 map_ciaoname(CiaoName, SWIName). 184ciao_term_expansion((:- new_declaration(Name/Arity)), Exp) :- 185 '$current_source_module'(M), 186 functor(Head, Name, Arity), 187 ( ciao:declaration(Head, M) 188 -> Exp = [] 189 ; Exp = ciao:declaration(Head, M) 190 ). 191ciao_term_expansion((:- package(_Package)), []). 192ciao_term_expansion((:- Decl), Exp) :- 193 '$current_source_module'(M), 194 declaration(Decl, M), 195 ( declaration_hook(Decl, Exp) 196 -> true 197 ; functor(Decl, Name, Arity), 198 prolog_load_context(module, Module), 199 current_predicate(Module:Name/Arity) 200 -> Exp = (:- Decl) 201 ; Exp = [] 202 ).

210map_metaspecs(Var, _) --> 211 { var(Var), !, 212 instantiation_error(Var) 213 }. 214map_metaspecs((A0,B0), (A,B)) --> !, 215 map_metaspecs(A0, A), 216 map_metaspecs(B0, B). 217map_metaspecs(Head0, Head) --> 218 { functor(Head0, Name, Arity), 219 functor(Head, Name, Arity), 220 functor(HeadIn, Name, Arity), 221 HeadIn =.. [Name|ArgsIn], 222 meta_expansion(Head0, Head, HeadIn, M, RequiresModule, ArgsOut, []) 223 }, 224 ( { ArgsIn == ArgsOut } -> [] 225 ; { HeadOut =.. [Name|ArgsOut] }, 226 ( {RequiresModule==1} -> 227 [ (:- module_transparent(Name/Arity)) ], 228 { Body = (context_module(M), HeadOut) } 229 ; { Body = HeadOut } 230 ), 231 [ (HeadIn :- Body) ] 232 ). 233 234map_metaspec(Var, ?) :- 235 var(Var), !. 236map_metaspec(goal, 0). 237map_metaspec(clause, :). 238map_metaspec(fact, :). 239map_metaspec(spec, :). 240map_metaspec(pred(N), N). 241map_metaspec(?, ?). 242map_metaspec(+, +). 243map_metaspec(-, -). 244 245module_sensitive(goal). 246module_sensitive(clause). 247module_sensitive(fact). 248module_sensitive(spec). 249module_sensitive(pred(_)). 250 251meta_expansion(Head0, Head, HeadIn, M, RequiresModule) --> 252 meta_expansion_args(1, Head0, Head, HeadIn, M, RequiresModule). 253 254meta_expansion_arg(Spec, TSpec, Arg, _, _) --> 255 {map_metaspec(Spec, TSpec)}, !, 256 [Arg]. 257meta_expansion_arg(addmodule(Spec), TSpec, Arg, M, 1) --> !, 258 meta_expansion_arg(Spec, TSpec, Arg, M, _), 259 [M]. 260meta_expansion_arg(addterm(Spec), TSpec, Arg0, M, R) --> !, 261 meta_expansion_arg(Spec, TSpec, Arg0, M, R), 262 { module_sensitive(Spec) -> Arg0 = _:Arg 263 ; Arg0 = Arg 264 }, 265 [Arg]. 266meta_expansion_arg(addmodule, TSpec, Arg, M, R) --> !, 267 meta_expansion_arg(addmodule(?), TSpec, Arg, M, R). 268meta_expansion_arg(addterm, TSpec, Arg, M, R) --> !, 269 meta_expansion_arg(addterm(?), TSpec, Arg, M, R). 270meta_expansion_arg(Spec, Spec, Arg, _, _) --> [Arg]. 271 272meta_expansion_args(N, Meta, Head, HeadIn, M, R) --> 273 {arg(N, Meta, Spec)}, 274 {arg(N, Head, TSpec)}, 275 {arg(N, HeadIn, Arg)}, 276 meta_expansion_arg(Spec, TSpec, Arg, M, R), 277 {N1 is N + 1}, 278 !, 279 meta_expansion_args(N1, Meta, Head, HeadIn, M, R). 280meta_expansion_args(_, _, _, _, _, _) --> []. 281 282ciao_term_expansion((:- use_module(CiaoName)), (:- use_module(SWIName))) :- 283 map_ciaoname(CiaoName, SWIName). 284ciao_term_expansion((:- use_module(CiaoName, L)), (:- use_module(SWIName, L))) :- 285 map_ciaoname(CiaoName, SWIName). 286ciao_term_expansion((:- include(CiaoName)), (:- include(SWIName))) :- 287 map_ciaoname(CiaoName, SWIName). 288ciao_term_expansion((:- reexport(CiaoName)), (:- reexport(SWIName))) :- 289 map_ciaoname(CiaoName, SWIName). 290ciao_term_expansion((:- reexport(CiaoName, L)), (:- reexport(SWIName, L))) :- 291 map_ciaoname(CiaoName, SWIName). 292ciao_term_expansion((:- meta_predicate(CiaoSpec)), 293 [ (:- meta_predicate(SWISpec)) 294 | Wrappers 295 ]) :- 296 ( phrase(map_metaspecs(CiaoSpec, SWISpec), Wrappers) 297 -> true 298 ; debug(ciao, 'Failed to translate ~q', 299 [(:- meta_predicate(CiaoSpec))]), 300 fail 301 ). 302ciao_term_expansion((:- data(Data)), (:- dynamic(Data))). 303ciao_term_expansion((:- primitive_meta_predicate(CiaoSpec)), SWIDecl) :- 304 expand_term((:- meta_predicate(CiaoSpec)), SWIDecl). 305ciao_term_expansion((:- redefining(F/A)), (:- redefine_system_predicate(H))) :- 306 functor(H, F, A). 307ciao_term_expansion((:- load_compilation_module(CiaoName)), 308 [(:- CM:use_module(SWIName))]) :- 309 compilation_module(CM), 310 map_ciaoname(CiaoName, SWIName). 311ciao_term_expansion((:- add_sentence_trans(F/A, P)), 312 [ciao:ciao_trans_db(CM, sentence, P, F, A)|Clauses]) :- 313 '$current_source_module'(M), 314 compilation_module(M, CM), 315 ( current_predicate(CM:F/A) -> 316 functor(H, F, A), 317 arg(1, H, 0), 318 arg(2, H, CL), 319 ignore(arg(3, H, M)), 320 ignore(CM:H), 321 ( var(CL) 322 -> Clauses = [] 323 ; is_list(CL) 324 -> Clauses = CL 325 ; Clauses = [CL] 326 ) 327 ; throw(error(existence_error(add_sentence_trans, F/A), _)) 328 ). 329ciao_term_expansion((:- add_goal_trans(F/A, P)), 330 ciao:ciao_trans_db(CM, goal, P, F, A)) :- 331 compilation_module(CM), 332 ( current_predicate(CM:F/A) -> true 333 ; throw(error(existence_error(add_goal_trans, F/A), _)) 334 ). 335ciao_term_expansion((H :- B), Clause) :- 336 % In Ciao, A :- A is one of the ways 337 % to tell the system A is a built-in. 338 H == B, !, 339 functor(H, F, A), 340 Clause = (:- export(F/A)). 341ciao_term_expansion((:- impl_defined(L)), Clauses) :- 342 '$current_source_module'(M), 343 findall(H, ( sequence_contains(L, bad_spec_error(impl_defined), F, A), 344 \+ current_predicate(M:F/A), 345 functor(H, F, A) 346 ), 347 Clauses). % Define dummy implementations to the 348 % impl_defined predicates that do not have a 349 % real implementation to avoid warnings. 350 351bad_spec_error(impl_defined, Spec) :- 352 throw(error(domain_error(predname, Spec), _)). 353 354:- meta_predicate sequence_contains(+,1,-,-). 355sequence_contains(V, BadP, _, _) :- var(V), !, 356 call(BadP, V), fail. 357sequence_contains([], _, _, _) :- !, fail. 358sequence_contains([S|Ss], BadP, F, A) :- !, 359 ( sequence_contains(S, BadP, F, A) 360 ; sequence_contains(Ss, BadP, F, A) 361 ). 362sequence_contains((S,Ss), BadP, F, A) :- !, 363 ( sequence_contains(S, BadP, F, A) 364 ; sequence_contains(Ss, BadP, F, A) 365 ). 366sequence_contains(F/A, _, F, A) :- 367 atom(F), integer(A), !. 368sequence_contains(S, BadP, _, _) :- 369 call(BadP, S), fail. 370 371get_expansor(F, A, M, Dict, Term0, Term, TR) :- 372 functor(TR, F, A), 373 arg(1, TR, Term0), 374 arg(2, TR, Term), 375 ignore(arg(3, TR, M)), 376 ignore(arg(4, TR, Dict)). 377 378call_sentence_expansion([], _, _, _, Term, Pos, Term, Pos). 379call_sentence_expansion([F/A|PIs], CM, M, Dict, Term0, Pos0, Term, Pos) :- 380 ( get_expansor(F, A, M, Dict, Term0, Term1, Expansor), 381 CM:Expansor -> 382 '$expand':expand_terms(ciao:call_sentence_expansion(PIs, CM, M, Dict), 383 Term1, Pos0, Term, Pos) 384 ; call_sentence_expansion(PIs, CM, M, Dict, Term0, Pos0, Term, Pos) 385 ). 386 387call_goal_expansion([], _, _, _, Term, Term). 388call_goal_expansion([F/A|PIs], CM, M, Dict, Term0, Term) :- 389 ( get_expansor(F, A, M, Dict, Term0, Term1, Expansor), 390 CM:Expansor -> true 391 ; Term0 = Term1 392 ), 393 call_goal_expansion(PIs, CM, M, Dict, Term1, Term). 394 395call_expansion(sentence, PIs, CM, M, Dict, Term0, Term) :- 396 call_sentence_expansion(PIs, CM, M, Dict, Term0, _, Term, _). 397call_expansion(goal, PIs, CM, M, Dict, Term0, Term) :- 398 call_goal_expansion(PIs, CM, M, Dict, Term0, Term). 399 400:- use_module(library(prolog_clause), []). % read_term_at_line/6 401:- use_module(library(pairs), [pairs_values/2]). 402 403get_expansors(CM, Trans, PIs) :- 404 findall(P-(F/A), ciao_trans_db(CM, Trans, P, F, A), UKPIs), 405 keysort(UKPIs, KPIs), 406 pairs_values(KPIs, PIs). 407 408% :- meta_predicate ciao_trans(:, ?, ?, ?). 409ciao_trans(CM, Trans, Term0, Term) :- 410 get_expansors(CM, Trans, PIs), 411 PIs \= [], 412 '$current_source_module'(M), 413 b_getval('$variable_names', Dict), 414 call_expansion(Trans, PIs, CM, M, Dict, Term0, Term). 415 416swi_meta_arg(_, Arg, Arg) :- 417 (var(Arg) ; atom(Arg)), !. 418swi_meta_arg(_, M:Arg, M:Arg) :- 419 (var(M) ; atom(M)), 420 (var(Arg) ; atom(Arg)), !. 421swi_meta_arg(_, '$ciao_meta'(Arg), '$ciao_meta'(Arg)) :- !. 422swi_meta_arg(Meta, Arg, '$ciao_meta'(Arg)) :- integer(Meta), Meta > 0, !. 423swi_meta_arg(_, _, Arg, Arg). 424 425swi_meta_args(Spec, CiaoGoal, SWIGoal) :- 426 functor(CiaoGoal, F, A), 427 functor(SWIGoal, F, A), 428 swi_meta_args(1, Spec, CiaoGoal, SWIGoal). 429 430swi_meta_args(N, Spec, CiaoGoal, SWIGoal) :- 431 arg(N, Spec, Meta), 432 !, 433 arg(N, CiaoGoal, CiaoArg), 434 arg(N, SWIGoal, SWIArg), 435 swi_meta_arg(Meta, CiaoArg, SWIArg), 436 N1 is N + 1, 437 swi_meta_args(N1, Spec, CiaoGoal, SWIGoal). 438swi_meta_args(_, _, _, _).

445:- meta_predicate 446 '$ciao_meta'(1, ?), 447 '$ciao_meta'(2, ?, ?), 448 '$ciao_meta'(3, ?, ?, ?), 449 '$ciao_meta'(4, ?, ?, ?, ?), 450 '$ciao_meta'(5, ?, ?, ?, ?, ?), 451 '$ciao_meta'(6, ?, ?, ?, ?, ?, ?), 452 '$ciao_meta'(7, ?, ?, ?, ?, ?, ?, ?). 453 454'$ciao_meta'(M:P0, A1) :- 455 P0 =.. [F|Args], 456 P =.. [F, A1|Args], 457 call(M:P). 458'$ciao_meta'(M:P0, A1, A2) :- 459 P0 =.. [F|Args], 460 P =.. [F, A1|Args], 461 call(M:P, A2). 462'$ciao_meta'(M:P0, A1, A2, A3) :- 463 P0 =.. [F|Args], 464 P =.. [F, A1|Args], 465 call(M:P, A2, A3). 466'$ciao_meta'(M:P0, A1, A2, A3, A4) :- 467 P0 =.. [F|Args], 468 P =.. [F, A1|Args], 469 call(M:P, A2, A3, A4). 470'$ciao_meta'(M:P0, A1, A2, A3, A4, A5) :- 471 P0 =.. [F|Args], 472 P =.. [F, A1|Args], 473 call(M:P, A2, A3, A4, A5). 474'$ciao_meta'(M:P0, A1, A2, A3, A4, A5, A6) :- 475 P0 =.. [F|Args], 476 P =.. [F, A1|Args], 477 call(M:P, A2, A3, A4, A5, A6). 478'$ciao_meta'(M:P0, A1, A2, A3, A4, A5, A6, A7) :- 479 P0 =.. [F|Args], 480 P =.. [F, A1|Args], 481 call(M:P, A2, A3, A4, A5, A6, A7). 482 483ciao_foldl(L, S, O, R) :- foldl(O, L, S, R). 484 485ciao_goal_expansion(atom_concat(A, B), atomic_list_concat(A, B)) :- !. 486ciao_goal_expansion(asserta_fact(Fact), asserta(Fact)) :- !. 487ciao_goal_expansion(asserta_fact(Fact, Ref), asserta(Fact, Ref)) :- !. 488ciao_goal_expansion(assertz_fact(Fact), assertz(Fact)) :- !. 489ciao_goal_expansion(assertz_fact(Fact, Ref), assertz(Fact, Ref)) :- !. 490ciao_goal_expansion(retract_fact(Fact), retract(Fact)) :- !. 491ciao_goal_expansion(retract_fact_nb(Fact), retract(Fact)) :- !. 492ciao_goal_expansion(retract_fact(Fact, Ref), retract(Fact, Ref)) :- !. 493ciao_goal_expansion(retract_fact_nb(Fact, Ref), retract(Fact, Ref)) :- !. 494ciao_goal_expansion(retractall_fact(Fact), retractall(Fact)) :- !. 495ciao_goal_expansion(current_fact(Fact), clause(Fact, _)) :- !. 496ciao_goal_expansion(current_fact(Fact, Ref), clause(Fact, _, Ref)) :- !. 497ciao_goal_expansion(current_fact_nb(Fact), clause(Fact, _)) :- !. 498ciao_goal_expansion(current_fact_nb(Fact, Ref), clause(Fact, _, Ref)) :- !. 499ciao_goal_expansion('$exit'(Code), halt(Code)) :- !. 500ciao_goal_expansion('$metachoice'(Choice), prolog_current_choice(Choice)) :- !. 501ciao_goal_expansion('$metacut'(Choice), prolog_cut_to(Choice)) :- !. 502ciao_goal_expansion('$meta_call'(Goal), call(Goal)) :- !. 503ciao_goal_expansion('$setarg'(Arg, Term, Value, on), setarg(Arg, Term, Value)) :- !. 504ciao_goal_expansion('$setarg'(Arg, Term, Value, true), nb_setarg(Arg, Term, Value)) :- !. 505ciao_goal_expansion(instance(A, B), subsumes_term(B, A)) :- !. 506ciao_goal_expansion(varset(A, B), term_variables(A, B)) :- !. 507ciao_goal_expansion(foldl(L, S, O, R), ciao_foldl(L, S, O, R)) :- !. 508ciao_goal_expansion(attach_attribute(V, A), put_attr(V, attributes, A)) :- !. 509ciao_goal_expansion(detach_attribute(V), del_attr(V, attributes)) :- !. 510ciao_goal_expansion(update_attribute(V, A), put_attr(V, attributes, A)) :- !. 511ciao_goal_expansion(get_attribute(V, A), get_attr(V, attributes, A)) :- !. 512ciao_goal_expansion(mktemp_in_tmp(T, F), tmp_file(T, F)) :- !. 513 514ciao_goal_expansion(current_prolog_flag(F, V), G) :- 515 F == discontiguous_warnings, 516 !, 517 G = (style_check(?(discontiguous)) -> V = on ; v = off). 518ciao_goal_expansion(set_prolog_flag(F, V), G) :- 519 F == discontiguous_warnings, 520 !, 521 ( V == on -> G = style_check(+(discontiguous)) 522 ; V == off -> G = style_check(-(discontiguous)) 523 ). 524ciao_goal_expansion(push_prolog_flag(Flag, NewValue), G) :- !, 525 expand_push_prolog_flag(Flag, NewValue, G). 526ciao_goal_expansion(push_ciao_flag(Flag, NewValue), G) :- !, 527 expand_push_prolog_flag(Flag, NewValue, G). 528ciao_goal_expansion(pop_prolog_flag(Flag), G) :- !, 529 expand_pop_prolog_flag(Flag, G). 530ciao_goal_expansion(pop_ciao_flag(Flag), G) :- !, 531 expand_pop_prolog_flag(Flag, G). 532 533ciao_goal_expansion(CiaoGoal, SWIGoal) :- 534 CiaoGoal \= _:_, 535 \+ functor(CiaoGoal, '$ciao_meta', _), 536 '$current_source_module'(M), 537 predicate_property(M:CiaoGoal, meta_predicate(Spec)), 538 swi_meta_args(Spec, CiaoGoal, SWIGoal), 539 CiaoGoal \= SWIGoal. 540 541expand_push_prolog_flag(Flag, NewValue, G) :- 542 '$current_source_module'(M), 543 G = ( nonvar(Flag), 544 prolog_flag(Flag, OldValue, NewValue), 545 asserta(ciao:old_flag(M, Flag, OldValue))). 546 547expand_pop_prolog_flag(Flag, G) :- 548 '$current_source_module'(M), 549 G = ( nonvar(Flag), 550 once(retract(ciao:old_flag(M, Flag, OldValue))), 551 prolog_flag(Flag, _, OldValue)). 552 553 /******************************* 554 * LIBRARY SETUP * 555 *******************************/

562push_ciao_library :- 563 ( absolute_file_name(library(dialect/ciao), Dir, 564 [ file_type(directory), 565 access(read), 566 solutions(all), 567 file_errors(fail) 568 ]), 569 asserta((user:file_search_path(library, Dir) :- 570 prolog_load_context(dialect, ciao))), 571 fail 572 ; true 573 ). 574 575 576:- push_ciao_library.