/*************************************************************************
* *
* YAP Prolog *
* *
* Yap Prolog was developed at NCCUP - Universidade do Porto *
* *
* Copyright L.Damas, V.S.Costa and Universidade do Porto 1985-1997 *
* *
**************************************************************************
* *
* File: boot.yap *
* Last rev: 8/2/88 *
* mods: *
* comments: boot file for Prolog *
* *
*************************************************************************/
% process an input clause
% This one should come first so that disjunctions and long distance
% cuts are compiled right with co-routining.
%
true :- true.
'$live' :-
'$init_system',
'$do_live'.
'$do_live' :-
repeat,
'$set_input'(user),'$set_output'(user),
'$current_module'(Module),
( Module=user ->
'$compile_mode'(_,0)
;
format(user_error,'[~w]~n', [Module])
),
'$system_catch'('$enter_top_level',Module,Error,user:'$Error'(Error)).
'$init_system' :-
% do catch as early as possible
(
'$access_yap_flags'(15, 0), \+ '$uncaught_throw' ->
'$version'
;
true
),
'$set_yap_flags'(10,0),
set_value(fileerrors,1),
set_value('$gc',on),
set_value('$verbose',on),
('$exit_undefp' -> true ; true),
prompt(' ?- '),
(
get_value('$break',0)
->
% '$set_read_error_handler'(error), let the user do that
% after an abort, make sure all spy points are gone.
'$clean_debugging_info',
% simple trick to find out if this is we are booting from Prolog.
get_value('$user_module',V),
( V = [] ->
'$current_module'(_,prolog)
;
'$current_module'(_,V), '$compile_mode'(_,0),
('$access_yap_flags'(16,0) ->
( exists('~/.yaprc') -> [-'~/.yaprc'] ; true ),
( exists('~/.prologrc') -> [-'~/.prologrc'] ; true ),
( exists('~/prolog.ini') -> [-'~/prolog.ini'] ; true )
;
true
)
),
'$db_clean_queues'(0),
'$startup_reconsult',
'$startup_goals'
;
true
).
%
% encapsulate $cut_by because of co-routining.
%
'$cut_by'(X) :- '$$cut_by'(X).
% Start file for yap
/* I/O predicates */
/* meaning of flags for '$write' is
1 quote illegal atoms
2 ignore operator declarations
4 output '$VAR'(N) terms as A, B, C, ...
8 use portray(_)
*/
/* main execution loop */
'$read_vars'(Stream,T,Pos,V) :-
'$read'(true,T,V,Pos,Err,Stream),
(nonvar(Err) ->
'$print_message'(error,Err), fail
;
true
).
% reset alarms when entering top-level.
'$enter_top_level' :-
'$alarm'(0, _),
fail.
'$enter_top_level' :-
'$clean_up_dead_clauses',
fail.
'$enter_top_level' :-
recorded('$restore_goal',G,R),
erase(R),
prompt(_,' | '),
'$system_catch'('$do_yes_no'((G->true),user),user,Error,user:'$Error'(Error)),
fail.
'$enter_top_level' :-
( recorded('$trace',on,_) ->
format(user_error, '% trace~n', [])
;
recorded('$debug', on, _) ->
format(user_error, '% debug~n', [])
),
fail.
'$enter_top_level' :-
prompt(_,' ?- '),
prompt(' | '),
'$run_toplevel_hooks',
'$read_vars'(user_input,Command,_,Varnames),
set_value(spy_gn,1),
( recorded('$spy_skip',_,R), erase(R), fail ; true),
( recorded('$spy_stop',_,R), erase(R), fail ; true),
prompt(_,' |: '),
'$command'((?-Command),Varnames,top),
'$sync_mmapped_arrays',
set_value('$live','$false').
'$startup_goals' :-
recorded('$startup_goal',G,_),
'$current_module'(Module),
'$system_catch'('$query'((G->true), []),Module,Error,user:'$Error'(Error)),
fail.
'$startup_goals'.
'$startup_reconsult' :-
get_value('$consult_on_boot',X), X \= [], !,
set_value('$consult_on_boot',[]),
'$do_startup_reconsult'(X).
'$startup_reconsult'.
%
% remove any debugging info after an abort.
%
'$clean_debugging_info' :-
recorded('$spy',_,R),
erase(R),
fail.
'$clean_debugging_info'.
'$erase_sets' :-
eraseall('$'),
eraseall('$$set'),
eraseall('$$one'),
eraseall('$reconsulted'), fail.
'$erase_sets' :- \+ recorded('$path',_,_), recorda('$path',"",_).
'$erase_sets'.
'$version' :-
get_value('$version_name',VersionName),
'$print_message'(help, version(VersionName)),
fail.
'$version' :- recorded('$version',VersionName,_),
'$print_message'(help, VersionName),
fail.
'$version'.
repeat :- '$repeat'.
'$repeat'.
'$repeat'.
'$repeat'.
'$repeat'.
'$repeat'.
'$repeat'.
'$repeat'.
'$repeat'.
'$repeat'.
'$repeat' :- '$repeat'.
'$start_corouts' :- recorded('$corout','$corout'(Name,_,_),R), Name \= main, finish_corout(R),
fail.
'$start_corouts' :-
eraseall('$corout'),
eraseall('$result'),
eraseall('$actual'),
fail.
'$start_corouts' :- recorda('$actual',main,_),
recordz('$corout','$corout'(main,main,'$corout'([],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[])),_Ref),
recorda('$result',going,_).
'$command'(C,VL,Con) :-
'$access_yap_flags'(9,1), !,
'$execute_command'(C,VL,Con,C).
'$command'(C,VL,Con) :-
( (Con = top ; var(C) ; C = [_|_]) ->
'$execute_command'(C,VL,Con,C), ! ;
expand_term(C, EC),
'$execute_commands'(EC,VL,Con,C)
).
%
% Hack in case expand_term has created a list of commands.
%
'$execute_commands'(V,_,_,Source) :- var(V), !,
'$do_error'(instantiation_error,meta_call(Source)).
'$execute_commands'([],_,_,_) :- !, fail.
'$execute_commands'([C|Cs],VL,Con,Source) :- !,
(
'$execute_command'(C,VL,Con,Source)
;
'$execute_commands'(Cs,VL,Con,Source)
),
fail.
'$execute_commands'(C,VL,Con,Source) :-
'$execute_command'(C,VL,Con,Source).
%
%
%
'$execute_command'(C,_,top,Source) :- var(C), !,
'$do_error'(instantiation_error,meta_call(Source)).
'$execute_command'(C,_,top,Source) :- number(C), !,
'$do_error'(type_error(callable,C),meta_call(Source)).
'$execute_command'(R,_,top,Source) :- db_reference(R), !,
'$do_error'(type_error(callable,R),meta_call(Source)).
'$execute_command'(end_of_file,_,_,_) :- !.
'$execute_command'((:-G),_,Option,_) :- !,
'$current_module'(M),
'$process_directive'(G, Option, M),
fail.
'$execute_command'((?-G),V,_,Source) :- !,
'$execute_command'(G,V,top,Source).
'$execute_command'(G,V,Option,Source) :-
'$continue_with_command'(Option,V,G,Source).
%
% This command is very different depending on the language mode we are in.
%
% ISO only wants directives in files
% SICStus accepts everything in files
% YAP accepts everything everywhere
%
'$process_directive'(G, top, M) :-
'$access_yap_flags'(8, 0), !, % YAP mode, go in and do it,
'$process_directive'(G, consult, M).
'$process_directive'(G, top, _) :- !,
'$do_error'(context_error((:- G),clause),query).
%
% allow modules
%
'$process_directive'(M:G, Mode, _) :- !,
'$process_directive'(G, Mode, M).
%
% default case
%
'$process_directive'(Gs, Mode, M) :-
'$all_directives'(Gs), !,
'$exec_directives'(Gs, Mode, M).
%
% ISO does not allow goals (use initialization).
%
'$process_directive'(D, _, M) :-
'$access_yap_flags'(8, 1), !, % ISO Prolog mode, go in and do it,
'$do_error'(context_error((:- M:D),query),directive).
%
% but YAP and SICStus does.
%
'$process_directive'(G, _, M) :-
( '$do_yes_no'(G,M) -> true ; format(user_error,':- ~w:~w failed.~n',[M,G]) ),
'$do_not_creep'.
'$continue_with_command'(reconsult,V,G,Source) :-
'$go_compile_clause'(G,V,5,Source),
fail.
'$continue_with_command'(consult,V,G,Source) :-
'$go_compile_clause'(G,V,13,Source),
fail.
'$continue_with_command'(top,V,G,_) :-
'$query'(G,V),
'$do_not_creep'.
%
% not 100% compatible with SICStus Prolog, as SICStus Prolog would put
% module prefixes all over the place, although unnecessarily so.
%
'$go_compile_clause'(Mod:G,V,N,Source) :- !,
'$go_compile_clause'(G,V,N,Mod,Source).
'$go_compile_clause'((M:G :- B),V,N,Source) :- !,
'$current_module'(M1),
(M1 = M ->
NG = (G :- B)
;
'$preprocess_clause_before_mod_change'((G:-B),M1,M,NG)
),
'$go_compile_clause'(NG,V,N,M,Source).
'$go_compile_clause'(G,V,N,Source) :-
'$current_module'(Mod),
'$go_compile_clause'(G,V,N,Mod,Source).
'$go_compile_clause'(G, V, N, Mod, Source) :-
'$prepare_term'(G, V, G0, G1, Mod, Source),
'$$compile'(G1, G0, N, Mod).
'$prepare_term'(G, V, G0, G1, Mod, Source) :-
( get_value('$syntaxcheckflag',on) ->
'$check_term'(Source, V, Mod) ; true ),
'$precompile_term'(G, G0, G1, Mod).
% process an input clause
'$$compile'(G, G0, L, Mod) :-
'$head_and_body'(G,H,_),
'$flags'(H, Mod, Fl, Fl),
is(NFl, /\, Fl, 0x00002000),
( NFl \= 0 -> '$assertz_dynamic'(L,G,G0,Mod) ;
'$compile'(G, L, G0, Mod) ).
% process a clause for a static predicate
'$$compile_stat'(G,G0,L,H, Mod) :-
'$compile'(G,L,G0,Mod).
'$check_if_reconsulted'(N,A) :-
recorded('$reconsulted',X,_),
( X = N/A , !;
X = '$', !, fail;
fail
).
'$inform_as_reconsulted'(N,A) :-
recorda('$reconsulted',N/A,_).
'$clear_reconsulting' :-
recorded('$reconsulted',X,Ref),
erase(Ref),
X == '$', !,
( recorded('$reconsulting',_,R) -> erase(R) ).
/* Executing a query */
'$query'(end_of_file,_).
% ***************************
% * -------- YAPOR -------- *
% ***************************
'$query'(G,V) :-
\+ '$undefined'('$yapor_on', prolog),
'$yapor_on',
\+ '$undefined'('$start_yapor', prolog),
'$parallelizable'(G), !,
'$parallel_query'(G,V),
fail.
% end of YAPOR
'$query'(G,[]) :- !,
'$yes_no'(G,(?-)).
'$query'(G,V) :-
(
( recorded('$trace',on,_) -> '$creep' ; true),
'$execute'(G),
'$do_not_creep',
'$extract_goal_vars_for_dump'(V,LIV),
'$show_frozen'(G,LIV,LGs),
'$write_answer'(V, LGs, Written),
'$write_query_answer_true'(Written),
'$another',
!, fail ;
'$do_not_creep',
( '$undefined'('$print_message'(_,_),prolog) ->
'$present_answer'(user_error,"no~n", [])
;
print_message(help,no)
),
fail
).
'$yes_no'(G,C) :-
'$current_module'(M),
'$do_yes_no'(G,M),
'$do_not_creep',
'$show_frozen'(G, [], LGs),
'$write_answer'([], LGs, Written),
( Written = [] ->
!,'$present_answer'(C, yes);
'$another', !
),
fail.
'$yes_no'(_,_) :-
'$do_not_creep',
( '$undefined'('$print_message'(_,_),prolog) ->
'$present_answer'(user_error,"no~n", [])
;
print_message(help,no)
),
fail.
'$do_yes_no'([X|L], M) :- !, '$csult'([X|L], M).
'$do_yes_no'(G, M) :-
( recorded('$trace',on,_) -> '$creep' ; true),
'$execute'(M:G).
'$extract_goal_vars_for_dump'([],[]).
'$extract_goal_vars_for_dump'([[_|V]|VL],[V|LIV]) :-
'$extract_goal_vars_for_dump'(VL,LIV).
'$write_query_answer_true'([]) :- !,
format(user_error,'~ntrue',[]).
'$write_query_answer_true'(_).
'$show_frozen'(_,_,[]) :-
'$undefined'(all_attvars(LAV), attributes), !.
'$show_frozen'(G,V,LGs) :-
attributes:all_attvars(LAV),
LAV = [_|_], !,
'$convert_to_list_of_frozen_goals'(V,LAV,G,LGs).
'$show_frozen'(_,_,[]).
%
% present_answer has three components. First it flushes the streams,
% then it presents the goals, and last it shows any goals frozen on
% the arguments.
%
'$present_answer'(_,_):-
'$flush_all_streams',
fail.
'$present_answer'((?-), Answ) :-
get_value('$break',BL),
( BL \= 0 -> format(user_error, '[~p] ',[BL]) ;
true ),
( recorded('$print_options','$toplevel'(Opts),_) ->
write_term(user_error,Answ,Opts) ;
format(user_error,'~w',[Answ])
),
format(user_error,'~n', []).
'$another' :-
format(user_error,' ? ',[]),
'$get0'(user_input,C),
( C== 0'; -> '$skip'(user_input,10),
'$add_nl_outside_console',
fail
;
C== 10 -> '$add_nl_outside_console',
( '$undefined'('$print_message'(_,_),prolog) ->
format(user_error,'yes~n', [])
;
print_message(help,yes)
)
;
C== -1 -> halt
;
'$skip'(user_input,10), '$ask_again_for_another'
).
'$add_nl_outside_console' :-
'$is_same_tty'(user_input, user_error), !.
'$add_nl_outside_console' :-
format(user_error,'~n',[]).
'$ask_again_for_another' :-
format(user_error,'Action (\";\" for more choices, <return> for exit)', []),
'$another'.
'$write_answer'(_,_,_) :-
'$flush_all_streams',
fail.
'$write_answer'(Vs, LBlk, LAnsw) :-
'$purge_dontcares'(Vs,IVs),
'$sort'(IVs, NVs),
'$prep_answer_var_by_var'(NVs, LAnsw, LBlk),
'$name_vars_in_goals'(LAnsw, Vs, NLAnsw),
'$write_vars_and_goals'(NLAnsw).
'$purge_dontcares'([],[]).
'$purge_dontcares'([[[95|_]|_]|Vs],NVs) :- !,
'$purge_dontcares'(Vs,NVs).
'$purge_dontcares'([V|Vs],[V|NVs]) :-
'$purge_dontcares'(Vs,NVs).
'$prep_answer_var_by_var'([], L, L).
'$prep_answer_var_by_var'([[Name|Value]|L], LF, L0) :-
'$delete_identical_answers'(L, Value, NL, Names),
'$prep_answer_var'([Name|Names], Value, LF, LI),
'$prep_answer_var_by_var'(NL, LI, L0).
% fetch all cases that have the same solution.
'$delete_identical_answers'([], _, [], []).
'$delete_identical_answers'([[Name|Value]|L], Value0, FL, [Name|Names]) :-
Value == Value0, !,
'$delete_identical_answers'(L, Value0, FL, Names).
'$delete_identical_answers'([VV|L], Value0, [VV|FL], Names) :-
'$delete_identical_answers'(L, Value0, FL, Names).
% now create a list of pairs that will look like goals.
'$prep_answer_var'(Names, Value, LF, L0) :- var(Value), !,
'$prep_answer_unbound_var'(Names, LF, L0).
'$prep_answer_var'(Names, Value, [nonvar(Names,Value)|L0], L0).
% ignore unbound variables
'$prep_answer_unbound_var'([_], L, L) :- !.
'$prep_answer_unbound_var'(Names, [var(Names)|L0], L0).
'$gen_name_string'(I,L,[C|L]) :- I < 26, !, C is I+65.
'$gen_name_string'(I,L0,LF) :-
I1 is I mod 26,
I2 is I // 26,
C is I1+65,
'$gen_name_string'(I2,[C|L0],LF).
'$write_vars_and_goals'([]).
'$write_vars_and_goals'([G1|LG]) :-
'$write_goal_output'(G1),
'$write_remaining_vars_and_goals'(LG).
'$write_remaining_vars_and_goals'([]).
'$write_remaining_vars_and_goals'([G1|LG]) :-
format(user_error,',~n',[]),
'$write_goal_output'(G1),
'$write_remaining_vars_and_goals'(LG).
'$write_goal_output'(var([V|VL])) :-
format(user_error,'~s',[V]),
'$write_output_vars'(VL).
'$write_goal_output'(nonvar([V|VL],B)) :-
format(user_error,'~s',[V]),
'$write_output_vars'(VL),
format(user_error,' = ', []),
( recorded('$print_options','$toplevel'(Opts),_) ->
write_term(user_error,B,Opts) ;
format(user_error,'~w',[B])
).
'$write_goal_output'(_-G) :-
( recorded('$print_options','$toplevel'(Opts),_) ->
write_term(user_error,G,Opts) ;
format(user_error,'~w',[G])
).
'$name_vars_in_goals'(G, VL0, NG) :-
'$copy_term_but_not_constraints'(G+VL0, NG+NVL0),
'$name_well_known_vars'(NVL0),
'$variables_in_term'(NG, [], NGVL),
'$name_vars_in_goals1'(NGVL, 0, _).
'$name_well_known_vars'([]).
'$name_well_known_vars'([[Name|V]|NVL0]) :-
var(V), !,
V = '$VAR'(Name),
'$name_well_known_vars'(NVL0).
'$name_well_known_vars'([_|NVL0]) :-
'$name_well_known_vars'(NVL0).
'$name_vars_in_goals1'([], I, I).
'$name_vars_in_goals1'(['$VAR'([95|Name])|NGVL], I0, IF) :-
I is I0+1,
'$gen_name_string'(I0,[],Name), !,
'$name_vars_in_goals1'(NGVL, I, IF).
'$name_vars_in_goals1'([NV|NGVL], I0, IF) :-
nonvar(NV),
'$name_vars_in_goals1'(NGVL, I0, IF).
'$write_output_vars'([]).
'$write_output_vars'([V|VL]) :-
format(user_error,' = ~s',[V]),
'$write_output_vars'(VL).
call(G) :- '$execute'(G).
incore(G) :- '$execute'(G).
%
% standard meta-call, called if $execute could not do everything.
%
'$meta_call'(G, M) :-
'$save_current_choice_point'(CP),
'$call'(G, CP, G, M).
','(X,Y) :-
'$save_current_choice_point'(CP),
'$current_module'(M),
'$call'(X,CP,(X,Y),M),
'$call'(Y,CP,(X,Y),M).
';'(X,Y) :-
'$save_current_choice_point'(CP),
'$current_module'(M),
( '$call'(X,CP,(X;Y),M) ; '$call'(Y,CP,(X;Y),M) ).
'|'(X,Y) :-
'$save_current_choice_point'(CP),
'$current_module'(M),
( '$call'(X,CP,(X|Y),M) ; '$call'(Y,CP,(X|Y),M) ).
'->'(X,Y) :-
'$save_current_choice_point'(CP),
'$current_module'(M),
( '$call'(X,CP,G0,M) -> '$call'(Y,CP,(X->Y),M) ).
\+(G) :- \+ '$execute'(G).
not(G) :- \+ '$execute'(G).
%
% do it in ISO mode.
%
'$meta_call'(G,_ISO,M) :-
'$iso_check_goal'(G,G),
'$save_current_choice_point'(CP),
'$call'(G, CP, G, M).
'$meta_call'(G, CP, G0, M) :-
'$call'(G, CP, G0, M).
'$call'(G, CP, G0, _, M) :- /* iso version */
'$iso_check_goal'(G,G0),
'$call'(G, CP, G0, M).
'$call'(M:_,_,G0,_) :- var(M), !,
'$do_error'(instantiation_error,call(G0)).
'$call'(M:G,CP,G0,_) :- !,
'$call'(G,CP,G0,M).
'$call'((X,Y),CP,G0,M) :- !,
'$call'(X,CP,G0,M),
'$call'(Y,CP,G0,M).
'$call'((X->Y),CP,G0,M) :- !,
(
'$call'(X,CP,G0,M)
->
'$call'(Y,CP,G0,M)
).
'$call'((X->Y; Z),CP,G0,M) :- !,
(
'$call'(X,CP,G0,M)
->
'$call'(Y,CP,G0,M)
;
'$call'(Z,CP,G0,M)
).
'$call'((A;B),CP,G0,M) :- !,
(
'$call'(A,CP,G0,M)
;
'$call'(B,CP,G0,M)
).
'$call'((X->Y| Z),CP,G0,M) :- !,
(
'$call'(X,CP,G0,M)
->
'$call'(Y,CP,G0,M)
;
'$call'(Z,CP,G0,M)
).
'$call'((A|B),CP, G0,M) :- !,
(
'$call'(A,CP,G0,M)
;
'$call'(B,CP,G0,M)
).
'$call'(\+ X, CP, G0, M) :- !,
\+ '$execute'(X).
'$call'(not(X), CP, G0, M) :- !,
\+ '$execute'(X).
'$call'(!, CP, _,_) :- !,
'$$cut_by'(CP).
'$call'([A|B], _, _, M) :- !,
'$csult'([A|B], M).
'$call'(G, CP, G0, CurMod) :-
( '$is_expand_goal_or_meta_predicate'(G,CurMod) ->
(
user:goal_expansion(G, CurMod, NG) ->
'$call'(NG, CP, G0,CurMod)
;
% repeat other code.
'$is_metapredicate'(G,CurMod) ->
(
'$meta_expansion'(CurMod,CurMod,G,NG,[]) ->
'$execute0'(NG, CurMod)
;
'$execute0'(G, CurMod)
)
;
'$execute0'(G, CurMod)
)
;
'$execute0'(G, CurMod)
).
'$check_callable'(V,G) :- var(V), !,
'$current_module'(Mod),
'$do_error'(instantiation_error,Mod:G).
'$check_callable'(A,G) :- number(A), !,
'$current_module'(Mod),
'$do_error'(type_error(callable,A),Mod:G).
'$check_callable'(R,G) :- db_reference(R), !,
'$current_module'(Mod),
'$do_error'(type_error(callable,R),Mod:G).
'$check_callable'(_,_).
% Called by the abstract machine, if no clauses exist for a predicate
'$undefp'([M|G]) :-
% make sure we do not loop on undefined predicates
% for undefined_predicates.
'$enter_undefp',
'$do_undefp'(G,M).
'$do_undefp'(G,M) :-
functor(G,F,N),
recorded('$import','$import'(S,M,F,N),_),
S \= M, % can't try importing from the module itself.
!,
'$exit_undefp',
(
'$meta_expansion'(S,M,G,G1,[])
->
'$execute'(S:G1)
;
'$execute'(S:G)
).
'$do_undefp'(G,M) :-
'$is_expand_goal_or_meta_predicate'(G,M),
'$system_catch'(goal_expansion(G, M, NG), user, _, fail), !,
'$exit_undefp',
'$execute0'(NG,M).
'$do_undefp'(G,M) :-
\+ '$undefined'(unknown_predicate_handler(_,_,_), user),
'$system_catch'(unknown_predicate_handler(G,M,NG), user, Error, '$leave_undefp'(Error)),
'$exit_undefp', !,
'$execute'(user:NG).
'$do_undefp'(G,M) :-
recorded('$unknown','$unknown'(M:G,US),_), !,
'$exit_undefp',
'$execute'(user:US).
'$do_undefp'(_,_) :-
'$exit_undefp',
fail.
'$leave_undefp'(Ball) :-
'$exit_undefp',
throw(Ball).
/* This is the break predicate,
it saves the importante data about current streams and
debugger state */
break :-
( recorded('$trace',Val,R) -> Trace = Val, erase(R); true),
( recorded('$debug',Val,R1) -> Debug = Val, erase(R1); true),
get_value('$break',BL), NBL is BL+1,
get_value(spy_gn,SPY_GN),
'$access_yap_flags'(10,SPY_CREEP),
get_value(spy_cl,SPY_CL),
get_value(spy_leap,_Leap),
set_value('$break',NBL),
current_output(OutStream), current_input(InpStream),
format(user_error, '% Break (level ~w)~n', [NBL]),
'$do_live',
!,
set_value('$live','$true'),
set_value(spy_gn,SPY_GN),
'$set_yap_flags'(10,SPY_CREEP),
set_value(spy_cl,SPY_CL),
set_value(spy_leap,_Leap),
'$set_input'(InpStream), '$set_output'(OutStream),
( recorded('$trace',_,R2), erase(R2), fail; true),
( recorded('$debug',_,R3), erase(R3), fail; true),
(nonvar(Trace) -> recorda('$trace',Trace,_)),
(nonvar(Debug) -> recorda('$debug',Debug,_)),
set_value('$break',BL).
'$csult'(V, _) :- var(V), !,
'$do_error'(instantiation_error,consult(V)).
'$csult'([], _).
'$csult'([-F|L], M) :- !, '$reconsult'(F, M), '$csult'(L, M).
'$csult'([F|L], M) :- '$consult'(F, M), '$csult'(L, M).
'$consult'(V, _) :- var(V), !,
'$do_error'(instantiation_error,consult(V)).
'$consult'([], _) :- !.
'$consult'([F|Fs], M) :- !,
'$consult'(F, M),
'$consult'(Fs, M).
'$consult'(M:X, _) :- !,
( atom(M) ->
'$consult'(X, M)
;
'$do_error'(type_error(atom,M),[M:X])
).
'$consult'(X, OldModule) :-
'$find_in_path'(X,Y,consult(X)),
'$open'(Y,'$csult',Stream,0), !,
'$consult'(X,OldModule,Stream),
'$close'(Stream).
'$consult'(X, _) :-
'$do_error'(permission_error(input,stream,X),[X]).
'$consult'(_,Module,Stream) :-
'$record_loaded'(Stream,Module),
fail.
'$consult'(F,Module,Stream) :-
'$access_yap_flags'(8, 2), % SICStus Prolog compatibility
!,
'$reconsult'(F,Module,Stream).
'$consult'(F,Mod,Stream) :-
'$current_module'(OldModule, Mod),
'$getcwd'(OldD),
get_value('$consulting_file',OldF),
'$set_consulting_file'(Stream),
H0 is heapused, '$cputime'(T0,_),
'$current_stream'(File,_,Stream),
'$start_consult'(consult,File,LC),
get_value('$consulting',Old),
set_value('$consulting',true),
recorda('$initialisation','$',_),
( '$undefined'('$print_message'(_,_),prolog) ->
( get_value('$verbose',on) ->
format(user_error, '~*|% consulting ~w...~n', [LC,F])
; true )
;
'$print_message'(informational, loading(consulting, File))
),
( recorded('$trace', on, TraceR) -> erase(TraceR) ; true),
'$loop'(Stream,consult),
'$end_consult',
( nonvar(TraceR) -> recorda('$trace', on, _) ; true),
set_value('$consulting',Old),
set_value('$consulting_file',OldF),
'$current_module'(NewMod,OldModule),
'$cd'(OldD),
( LC == 0 -> prompt(_,' |: ') ; true),
H is heapused-H0, '$cputime'(TF,_), T is TF-T0,
( '$undefined'('$print_message'(_,_),prolog) ->
( get_value('$verbose',on) ->
format(user_error, '~*|% ~w consulted ~w bytes in ~d msecs~n', [LC,F,H,T])
;
true
)
;
'$print_message'(informational, loaded(consulted, File, NewMod, T, H))
),
'$exec_initialisation_goals',
!.
'$record_loaded'(user, _).
'$record_loaded'(user_input, _).
'$record_loaded'(Stream, M) :-
'$loaded'(Stream, M, _), !.
'$record_loaded'(Stream, M) :-
'$file_name'(Stream,F),
'$file_age'(F,Age),
recorda('$loaded','$loaded'(F,M,Age),_).
'$set_consulting_file'(user) :- !,
set_value('$consulting_file',user_input).
'$set_consulting_file'(user_input) :- !,
set_value('$consulting_file',user_input).
'$set_consulting_file'(Stream) :-
'$file_name'(Stream,F),
set_value('$consulting_file',F),
'$set_consulting_dir'(F).
%
% Use directory where file exists
%
'$set_consulting_dir'(F) :-
atom_codes(F,S),
'$strip_file_for_scd'(S,Dir,Unsure,Unsure),
'$cd'(Dir).
%
% The algorithm: I have two states, one for what I am sure will be an answer,
% the other for what I have found so far.
%
'$strip_file_for_scd'([], [], _, _).
'$strip_file_for_scd'([D|L], Out, Out, Cont) :-
'$dir_separator'(D), !,
'$strip_file_for_scd'(L, Cont, [D|C2], C2).
'$strip_file_for_scd'([F|L], Out, Cont, [F|C2]) :-
'$strip_file_for_scd'(L, Out, Cont, C2).
'$loop'(Stream,Status) :-
'$change_alias_to_stream'('$loop_stream',Stream),
repeat,
( '$current_stream'(_,_,Stream) -> true
; '$abort_loop'(Stream)
),
prompt('| '), prompt(_,'| '),
'$current_module'(OldModule),
'$system_catch'('$enter_command'(Stream,Status), OldModule, Error,
user:'$LoopError'(Error, Status)),
!.
'$enter_command'(Stream,Status) :-
'$read_vars'(Stream,Command,_,Vars),
'$command'(Command,Vars,Status).
'$abort_loop'(Stream) :-
'$do_error'(permission_error(input,closed_stream,Stream), loop).
/* General purpose predicates */
'$head_and_body'((H:-B),H,B) :- !.
'$head_and_body'(H,H,true).
%
% split head and body, generate an error if body is unbound.
%
'$check_head_and_body'((H:-B),H,B,P) :- !,
'$check_head'(H,P).
'$check_head_and_body'(H,H,true,P) :-
'$check_head'(H,P).
'$check_head'(H,P) :- var(H), !,
'$do_error'(instantiation_error,P).
'$check_head'(H,P) :- number(H), !,
'$do_error'(type_error(callable,H),P).
'$check_head'(H,P) :- db_reference(H), !,
'$do_error'(type_error(callable,H),P).
'$check_head'(_,_).
% Path predicates
'$exists'(F,Mode) :-
get_value(fileerrors,V),
set_value(fileerrors,0),
( '$open'(F,Mode,S,0) -> '$close'(S), set_value(fileerrors,V) ; set_value(fileerrors,V), fail).
'$find_in_path'(user,user_input, _) :- !.
'$find_in_path'(user_input,user_input, _) :- !.
'$find_in_path'(S,NewFile, _) :-
S =.. [Name,File], !,
'$dir_separator'(D),
atom_codes(A,[D]),
( user:file_search_path(Name, Dir), '$do_not_creep' ; '$do_not_creep'),
atom_concat([Dir,A,File],NFile),
'$search_in_path'(NFile, NewFile).
'$find_in_path'(File,NewFile,_) :- atom(File), !,
'$search_in_path'(File,NewFile),!.
'$find_in_path'(File,_,Call) :-
'$do_error'(domain_error(source_sink,File),Call).
'$search_in_path'(New,New) :-
'$exists'(New,'$csult'), !.
'$search_in_path'(File,New) :-
recorded('$path',Path,_),
atom_concat([Path,File],New),
'$exists'(New,'$csult').
% term expansion
%
% return two arguments: Expanded0 is the term after "USER" expansion.
% Expanded is the final expanded term.
%
'$precompile_term'(Term, Expanded0, Expanded, Mod) :-
(
'$access_yap_flags'(9,1) /* strict_iso on */
->
'$expand_term_modules'(Term, Expanded0, Expanded, Mod),
'$check_iso_strict_clause'(Expanded0)
;
'$expand_term_modules'(Term, Expanded0, ExpandedI, Mod),
'$expand_array_accesses_in_term'(ExpandedI,Expanded)
).
expand_term(Term,Expanded) :-
( \+ '$undefined'(term_expansion(_,_), user),
user:term_expansion(Term,Expanded),
'$do_not_creep'
;
'$do_not_creep',
'$expand_term_grammar'(Term,Expanded)
),
!.
%
% Grammar Rules expansion
%
'$expand_term_grammar'((A-->B), C) :-
'$translate_rule'((A-->B),C), !.
'$expand_term_grammar'(A, A).
%
% Arithmetic expansion
%
'$expand_term_arith'(G1, G2) :-
get_value('$c_arith',true),
'$c_arith'(G1, G2), !.
'$expand_term_arith'(G,G).
%
% Arithmetic expansion
%
'$expand_array_accesses_in_term'(Expanded0,ExpandedF) :-
'$array_refs_compiled',
'$c_arrays'(Expanded0,ExpandedF), !.
'$expand_array_accesses_in_term'(Expanded,Expanded).
%
% Module system expansion
%
'$expand_term_modules'(A,B,C,M) :- '$module_expansion'(A,B,C,M), !.
'$expand_term_modules'(A,A,A,_).
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% catch/throw implementation
% at each catch point I need to know:
% what is ball;
% where was the previous catch
catch(G, C, A) :-
'$catch'(C,A,_),
'$execute'(G).
% system_catch is like catch, but it avoids the overhead of a full
% meta-call by calling '$execute0' instead of $execute.
% This way it
% also avoids module preprocessing and goal_expansion
%
'$system_catch'(G, M, C, A) :-
% check current trail
'$catch'(C,A,_),
'$execute_nonstop'(G, M).
%
% throw has to be *exactly* after system catch!
%
throw(Ball) :-
% get this off the unwound computation.
copy_term(Ball,NewBall),
% get current jump point
'$jump_env_and_store_ball'(NewBall).
% just create a choice-point
'$catch'(_,_,_).
'$catch'(_,_,_) :- fail.
'$handle_throw'(_, _, _).
'$handle_throw'(C, A, Ball) :-
% reset info
(Ball \== '$abort', C = Ball ->
'$execute'(A)
;
throw(Ball)
).
'$exec_initialisation_goals' :-
recorded('$blocking_code',_,R),
erase(R),
fail.
% system goals must be performed first
'$exec_initialisation_goals' :-
recorded('$system_initialisation',G,R),
erase(R),
G \= '$',
call(G),
fail.
'$exec_initialisation_goals' :-
recorded('$initialisation',G,R),
erase(R),
G \= '$',
'$current_module'(M),
'$system_catch'(once(M:G), M, Error, user:'$LoopError'(Error, top)),
'$do_not_creep',
fail.
'$exec_initialisation_goals'.
'$run_toplevel_hooks' :-
get_value('$break',0),
recorded('$toplevel_hooks',H,_), !,
( '$execute'(H) -> true ; true),
'$do_not_creep'.
'$run_toplevel_hooks'.