This repository has been archived on 2023-08-20. You can view files and clone it, but cannot push or open issues or pull requests.
yap-6.3/pl/utils.yap

854 lines
24 KiB
Plaintext
Raw Normal View History

/*************************************************************************
* *
* YAP Prolog *
* *
* Yap Prolog was developed at NCCUP - Universidade do Porto *
* *
* Copyright L.Damas, V.S.Costa and Universidade do Porto 1985-1997 *
* *
**************************************************************************
* *
* File: utils.yap *
* Last rev: 8/2/88 *
* mods: *
* comments: Some utility predicates available in yap *
* *
*************************************************************************/
once(G) :- '$execute'(G), !.
if(X,Y,Z) :-
yap_hacks:env_choice_point(CP0),
(
CP is '$last_choice_pt',
'$call'(X,CP,if(X,Y,Z),M),
'$execute'(X),
'$clean_ifcp'(CP),
'$call'(Y,CP,if(X,Y,Z),M)
;
'$call'(Z,CP,if(X,Y,Z),M)
).
call(X,A) :- '$execute'(X,A).
call(X,A1,A2) :- '$execute'(X,A1,A2).
call(X,A1,A2,A3) :- '$execute'(X,A1,A2,A3).
call(X,A1,A2,A3,A4) :- '$execute'(X,A1,A2,A3,A4).
call(X,A1,A2,A3,A4,A5) :- '$execute'(X,A1,A2,A3,A4,A5).
call(X,A1,A2,A3,A4,A5,A6) :- '$execute'(X,A1,A2,A3,A4,A5,A6).
call(X,A1,A2,A3,A4,A5,A6,A7) :- '$execute'(X,A1,A2,A3,A4,A5,A6,A7).
call(X,A1,A2,A3,A4,A5,A6,A7,A8) :- '$execute'(X,A1,A2,A3,A4,A5,A6,A7,A8).
call(X,A1,A2,A3,A4,A5,A6,A7,A8,A9) :- '$execute'(X,A1,A2,A3,A4,A5,A6,A7,A8,A9).
call(X,A1,A2,A3,A4,A5,A6,A7,A8,A9,A10) :- '$execute'(X,A1,A2,A3,A4,A5,A6,A7,A8,A9,A10).
call(X,A1,A2,A3,A4,A5,A6,A7,A8,A9,A10,A11) :- '$execute'(X,A1,A2,A3,A4,A5,A6,A7,A8,A9,A10,A11).
call_with_args(M:V) :- var(V), !,
'$do_error'(instantiation_error,call_with_args(M:V)).
call_with_args(_:M:A) :- !,
call_with_args(M:A).
call_with_args(M:A) :- !,
'$call_with_args'(A,M).
call_with_args(A) :- atom(A), !,
'$current_module'(M),
'$call_with_args'(A,M).
call_with_args(A) :-
'$do_error'(type_error(atom,A),call_with_args(A)).
call_with_args(M:V,A1) :- var(V), !,
'$do_error'(instantiation_error,call_with_args(M:V,A1)).
call_with_args(_:M:A,A1) :- !,
call_with_args(M:A,A1).
call_with_args(M:A,A1) :- !,
'$call_with_args'(A,A1,M).
call_with_args(A,A1) :- atom(A), !,
'$current_module'(M),
'$call_with_args'(A,A1,M).
call_with_args(A,A1) :-
'$do_error'(type_error(atom,A),call_with_args(A,A1)).
call_with_args(M:V,A1,A2) :- var(V), !,
'$do_error'(instantiation_error,call_with_args(M:V,A1,A2)).
call_with_args(_:M:A,A1,A2) :- !,
call_with_args(M:A,A1,A2).
call_with_args(M:A,A1,A2) :- !,
'$call_with_args'(A,A1,A2,M).
call_with_args(A,A1,A2) :- atom(A), !,
'$current_module'(M),
'$call_with_args'(A,A1,A2,M).
call_with_args(A,A1,A2) :-
'$do_error'(type_error(atom,A),call_with_args(A,A1,A2)).
call_with_args(M:V,A1,A2,A3) :- var(V), !,
'$do_error'(instantiation_error,call_with_args(M:V,A1,A2,A3)).
call_with_args(_:M:A,A1,A2,A3) :- !,
call_with_args(M:A,A1,A2,A3).
call_with_args(M:A,A1,A2,A3) :- !,
'$call_with_args'(A,A1,A2,A3,M).
call_with_args(A,A1,A2,A3) :- atom(A), !,
'$current_module'(M),
'$call_with_args'(A,A1,A2,A3,M).
call_with_args(A,A1,A2,A3) :-
'$do_error'(type_error(atom,A),call_with_args(A,A1,A2,A3)).
call_with_args(M:V,A1,A2,A3,A4) :- var(V), !,
'$do_error'(instantiation_error,call_with_args(M:V,A1,A2,A3,A4)).
call_with_args(_:M:A,A1,A2,A3,A4) :- !,
call_with_args(M:A,A1,A2,A3,A4).
call_with_args(M:A,A1,A2,A3,A4) :- !,
'$call_with_args'(A,A1,A2,A3,A4,M).
call_with_args(A,A1,A2,A3,A4) :- atom(A), !,
'$current_module'(M),
'$call_with_args'(A,A1,A2,A3,A4,M).
call_with_args(A,A1,A2,A3,A4) :-
'$do_error'(type_error(atom,A),call_with_args(A,A1,A2,A3,A4)).
call_with_args(M:V,A1,A2,A3,A4,A5) :- var(V), !,
'$do_error'(instantiation_error,call_with_args(M:V,A1,A2,A3,A4,A5)).
call_with_args(_:M:A,A1,A2,A3,A4,A5) :- !,
call_with_args(M:A,A1,A2,A3,A4,A5).
call_with_args(M:A,A1,A2,A3,A4,A5) :- !,
'$call_with_args'(A,A1,A2,A3,A4,A5,M).
call_with_args(A,A1,A2,A3,A4,A5) :- atom(A), !,
'$current_module'(M),
'$call_with_args'(A,A1,A2,A3,A4,A5,M).
call_with_args(A,A1,A2,A3,A4,A5) :-
'$do_error'(type_error(atom,A),call_with_args(A,A1,A2,A3,A4,A5)).
call_with_args(M:V,A1,A2,A3,A4,A5,A6) :- var(V), !,
'$do_error'(instantiation_error,call_with_args(M:V,A1,A2,A3,A4,A5,A6)).
call_with_args(_:M:A,A1,A2,A3,A4,A5,A6) :- !,
call_with_args(M:A,A1,A2,A3,A4,A5,A6).
call_with_args(M:A,A1,A2,A3,A4,A5,A6) :- !,
'$call_with_args'(A,A1,A2,A3,A4,A5,A6,M).
call_with_args(A,A1,A2,A3,A4,A5,A6) :- atom(A), !,
'$current_module'(M),
'$call_with_args'(A,A1,A2,A3,A4,A5,A6,M).
call_with_args(A,A1,A2,A3,A4,A5,A6) :-
'$do_error'(type_error(atom,A),call_with_args(A,A1,A2,A3,A4,A5,A6)).
call_with_args(M:V,A1,A2,A3,A4,A5,A6,A7) :- var(V), !,
'$do_error'(instantiation_error,call_with_args(M:V,A1,A2,A3,A4,A5,A6,A7)).
call_with_args(_:M:A,A1,A2,A3,A4,A5,A6,A7) :- !,
call_with_args(M:A,A1,A2,A3,A4,A5,A6,A7).
call_with_args(M:A,A1,A2,A3,A4,A5,A6,A7) :- !,
'$call_with_args'(A,A1,A2,A3,A4,A5,A6,A7,M).
call_with_args(A,A1,A2,A3,A4,A5,A6,A7) :- atom(A), !,
'$current_module'(M),
'$call_with_args'(A,A1,A2,A3,A4,A5,A6,A7,M).
call_with_args(A,A1,A2,A3,A4,A5,A6,A7) :-
'$do_error'(type_error(atom,A),call_with_args(A,A1,A2,A3,A4,A5,A6,A7)).
call_with_args(M:V,A1,A2,A3,A4,A5,A6,A7,A8) :- var(V), !,
'$do_error'(instantiation_error,call_with_args(M:V,A1,A2,A3,A4,A5,A6,A7,A8)).
call_with_args(_:M:A,A1,A2,A3,A4,A5,A6,A7,A8) :- !,
call_with_args(M:A,A1,A2,A3,A4,A5,A6,A7,A8).
call_with_args(M:A,A1,A2,A3,A4,A5,A6,A7,A8) :- !,
'$call_with_args'(A,A1,A2,A3,A4,A5,A6,A7,A8,M).
call_with_args(A,A1,A2,A3,A4,A5,A6,A7,A8) :- atom(A), !,
'$current_module'(M),
'$call_with_args'(A,A1,A2,A3,A4,A5,A6,A7,A8,M).
call_with_args(A,A1,A2,A3,A4,A5,A6,A7,A8) :-
'$do_error'(type_error(atom,A),call_with_args(A,A1,A2,A3,A4,A5,A6,A7,A8)).
call_with_args(M:V,A1,A2,A3,A4,A5,A6,A7,A8,A9) :- var(V), !,
'$do_error'(instantiation_error,call_with_args(M:V,A1,A2,A3,A4,A5,A6,A7,A8,A9)).
call_with_args(_:M:A,A1,A2,A3,A4,A5,A6,A7,A8,A9) :- !,
call_with_args(M:A,A1,A2,A3,A4,A5,A6,A7,A8,A9).
call_with_args(M:A,A1,A2,A3,A4,A5,A6,A7,A8,A9) :- !,
'$current_module'(M),
'$call_with_args'(A,A1,A2,A3,A4,A5,A6,A7,A8,A9,M).
call_with_args(A,A1,A2,A3,A4,A5,A6,A7,A8,A9) :- atom(A), !,
'$current_module'(M),
'$call_with_args'(A,A1,A2,A3,A4,A5,A6,A7,A8,A9,M).
call_with_args(A,A1,A2,A3,A4,A5,A6,A7,A8,A9) :-
'$do_error'(type_error(atom,A),call_with_args(A,A1,A2,A3,A4,A5,A6,A7,A8,A9)).
call_with_args(M:V,A1,A2,A3,A4,A5,A6,A7,A8,A9,A10) :- var(V), !,
'$do_error'(instantiation_error,call_with_args(M:V,A1,A2,A3,A4,A5,A6,A7,A8,A9,A10)).
call_with_args(_:M:A,A1,A2,A3,A4,A5,A6,A7,A8,A10) :- !,
call_with_args(M:A,A1,A2,A3,A4,A5,A6,A7,A8,A10).
call_with_args(M:A,A1,A2,A3,A4,A5,A6,A7,A8,A9,A10) :- !,
'$call_with_args'(A,A1,A2,A3,A4,A5,A6,A7,A8,A9,A10,M).
call_with_args(A,A1,A2,A3,A4,A5,A6,A7,A8,A9,A10) :- atom(A), !,
'$current_module'(M),
'$call_with_args'(A,A1,A2,A3,A4,A5,A6,A7,A8,A9,A10,M).
call_with_args(A,A1,A2,A3,A4,A5,A6,A7,A8,A9,A10) :-
'$do_error'(type_error(atom,A),call_with_args(A,A1,A2,A3,A4,A5,A6,A7,A8,A9,A10)).
call_cleanup(Goal, Cleanup) :-
call_cleanup(Goal, _Catcher, Cleanup).
call_cleanup(Goal, Catcher, Cleanup) :-
catch('$call_cleanup'(Goal,Cleanup,_),
Exception,
'$cleanup_exception'(Exception,Catcher,Cleanup)).
'$cleanup_exception'(Exception, exception(Exception), Cleanup) :- !,
'$clean_call'(Cleanup),
throw(Exception).
'$cleanup_exception'(Exception, _, _) :-
throw(Exception).
'$call_cleanup'(Goal, Cleanup, Result) :-
'$freeze_goal'(Result, '$clean_call'(Cleanup)),
yap_hacks:trail_suspension_marker(Result),
(
yap_hacks:current_choice_point(CP0),
'$execute'(Goal),
yap_hacks:current_choice_point(CPF),
(
CP0 =:= CPF ->
Result = exit,
!
;
true
)
;
Result = fail,
fail
).
'$holds_true'.
'$clean_call'(Cleanup) :-
'$execute'(Cleanup), !.
'$clean_call'(_).
op(P,T,V) :-
'$check_op'(P,T,V,op(P,T,V)),
'$op'(P, T, V).
'$check_op'(P,T,V,G) :-
(
var(P) ->
'$do_error'(instantiation_error,G)
;
var(T) ->
'$do_error'(instantiation_error,G)
;
var(V) ->
'$do_error'(instantiation_error,G)
;
\+ integer(P) ->
'$do_error'(type_error(integer,P),G)
;
\+ atom(T) ->
'$do_error'(type_error(atom,T),G)
;
P < 0 ->
'$do_error'(domain_error(out_of_range,P),G)
;
P > 1200 ->
'$do_error'(domain_error(out_of_range,P),G)
;
\+ '$associativity'(T) ->
'$do_error'(domain_error(operator_specifier,T),G)
;
'$check_op_name'(V,G)
).
'$associativity'(xfx).
'$associativity'(xfy).
'$associativity'(yfx).
'$associativity'(yfy).
'$associativity'(xf).
'$associativity'(yf).
'$associativity'(fx).
'$associativity'(fy).
'$check_op_name'(V,_) :-
atom(V), !.
'$check_op_name'(M:A, G) :-
(
var(M) ->
'$do_error'(instantiation_error,G)
;
var(A) ->
'$do_error'(instantiation_error,G)
;
\+ atom(A) ->
'$do_error'(instantiation_error,G)
;
\+ atom(M) ->
'$do_error'(instantiation_error,G)
;
true
).
'$check_op_name'([A|As], G) :-
'$check_op_name'(A, G),
'$check_op_names'(As, G).
'$check_op_names'([], _).
'$check_op_names'([A|As], G) :-
'$check_op_name'(A, G),
'$check_op_names'(As, G).
'$op'(P, T, [A|As]) :- !,
'$opl'(P, T, [A|As]).
'$op'(P, T, A) :-
'$op2'(P,T,A).
'$opl'(P, T, []).
'$opl'(P, T, [A|As]) :-
'$op2'(P, T, A),
'$opl'(P, T, As).
'$op2'(P,T,A) :-
atom(A), !,
'$opdec'(P,T,A,prolog).
'$op2'(P,T,A) :-
strip_module(A,M,N),
(M = user -> NM = prolog ; NM = M),
'$opdec'(P,T,N,NM).
current_op(X,Y,V) :- var(V), !,
'$current_module'(M),
V = M:Z,
'$do_current_op'(X,Y,Z,M).
current_op(X,Y,M:Z) :- !,
'$current_opm'(X,Y,Z,M).
current_op(X,Y,Z) :-
'$current_module'(M),
'$do_current_op'(X,Y,Z,M).
'$current_opm'(X,Y,Z,M) :-
var(Z), !,
'$do_current_op'(X,Y,Z,M).
'$current_opm'(X,Y,M:Z,_) :- !,
'$current_opm'(X,Y,Z,M).
'$current_opm'(X,Y,Z,M) :-
'$do_current_op'(X,Y,Z,M).
'$do_current_op'(X,Y,Z,M) :-
'$current_op'(X,Y,Z,M1),
( M1 = prolog -> true ; M1 = M ).
%%% Operating System utilities
unix(V) :- var(V), !,
'$do_error'(instantiation_error,unix(V)).
unix(argv(L)) :- '$is_list_of_atoms'(L,L), !, '$argv'(L).
unix(argv(V)) :-
'$do_error'(type_error(atomic,V),unix(argv(V))).
unix(cd) :- cd('~').
unix(cd(V)) :- var(V), !,
'$do_error'(instantiation_error,unix(cd(V))).
unix(cd(A)) :- atomic(A), !, cd(A).
unix(cd(V)) :-
'$do_error'(type_error(atomic,V),unix(cd(V))).
unix(environ(X,Y)) :- '$do_environ'(X,Y).
unix(getcwd(X)) :- getcwd(X).
unix(shell(V)) :- var(V), !,
'$do_error'(instantiation_error,unix(shell(V))).
unix(shell(A)) :- atom(A), !, '$shell'(A).
unix(shell(V)) :-
'$do_error'(type_error(atomic,V),unix(shell(V))).
unix(system(V)) :- var(V), !,
'$do_error'(instantiation_error,unix(system(V))).
unix(system(A)) :- atom(A), !, system(A).
unix(system(V)) :-
'$do_error'(type_error(atom,V),unix(system(V))).
unix(shell) :- sh.
unix(putenv(X,Y)) :- '$putenv'(X,Y).
'$is_list_of_atoms'(V,_) :- var(V),!.
'$is_list_of_atoms'([],_) :- !.
'$is_list_of_atoms'([H|L],L0) :- !,
'$check_if_head_may_be_atom'(H,L0),
'$is_list_of_atoms'(L,L0).
'$is_list_of_atoms'(H,L0) :-
'$do_error'(type_error(list,H),unix(argv(L0))).
'$check_if_head_may_be_atom'(H,_) :-
var(H), !.
'$check_if_head_may_be_atom'(H,_) :-
atom(H), !.
'$check_if_head_may_be_atom'(H,L0) :-
'$do_error'(type_error(atom,H),unix(argv(L0))).
'$do_environ'(X, Y) :-
var(X), !,
'$do_error'(instantiation_error,unix(environ(X,Y))).
'$do_environ'(X, Y) :- atom(X), !,
'$getenv'(X,Y).
'$do_environ'(X, Y) :-
'$do_error'(type_error(atom,X),unix(environ(X,Y))).
putenv(Na,Val) :-
'$putenv'(Na,Val).
getenv(Na,Val) :-
'$getenv'(Na,Val).
%%% Saving and restoring a computation
save(A) :- var(A), !,
'$do_error'(instantiation_error,save(A)).
save(A) :- atom(A), !, name(A,S), '$save'(S).
save(S) :- '$save'(S).
save(A,_) :- var(A), !,
'$do_error'(instantiation_error,save(A)).
save(A,OUT) :- atom(A), !, name(A,S), '$save'(S,OUT).
save(S,OUT) :- '$save'(S,OUT).
save_program(A) :- var(A), !,
'$do_error'(instantiation_error,save_program(A)).
save_program(A) :- atom(A), !, name(A,S), '$save_program'(S).
save_program(S) :- '$save_program'(S).
save_program(A, G) :- var(A), !,
'$do_error'(instantiation_error,save_program(A,G)).
save_program(A, G) :- var(G), !,
'$do_error'(instantiation_error,save_program(A,G)).
save_program(A, G) :- \+ callable(G), !,
'$do_error'(type_error(callable,G),save_program(A,G)).
save_program(A, G) :-
( atom(A) -> name(A,S) ; A = S),
recorda('$restore_goal',G,R),
'$save_program'(S),
erase(R),
fail.
save_program(_,_).
restore(A) :- var(A), !,
'$do_error'(instantiation_error,restore(A)).
restore(A) :- atom(A), !, name(A,S), '$restore'(S).
restore(S) :- '$restore'(S).
%%% current ....
recordaifnot(K,T,R) :-
recorded(K,T,R), % force non-det binding to R.
'$still_variant'(R,T),
!,
fail.
recordaifnot(K,T,R) :-
recorda(K,T,R).
recordzifnot(K,T,R) :-
recorded(K,T,R),
'$still_variant'(R,T),
!,
fail.
recordzifnot(K,T,R) :-
recordz(K,T,R).
current_atom(A) :- % check
atom(A), !.
current_atom(A) :- % generate
'$current_atom'(A).
current_atom(A) :- % generate
'$current_wide_atom'(A).
%%% The unknown predicate,
% informs about what the user wants to be done when
% there are no clauses for a certain predicate */
unknown(V0,V) :-
'$current_module'(M),
'$unknown'(V0,V,M).
% query mode
'$unknown'(V0,V,_) :- var(V), !,
'$ask_unknown_flag'(V),
V = V0.
% handle modules.
'$unknown'(V0,Mod:Handler,_) :-
'$unknown'(V0,Handler,Mod).
% check if we have one we like.
'$unknown'(_,New,Mod) :-
'$valid_unknown_handler'(New,Mod), fail.
% clean up previous unknown predicate handlers
'$unknown'(Old,New,Mod) :-
recorded('$unknown','$unknown'(_,MyOld),Ref), !,
erase(Ref),
'$cleanup_unknown_handler'(MyOld,Old),
'$new_unknown'(New, Mod).
% store the new one.
'$unknown'(fail,New,Mod) :-
'$new_unknown'(New, Mod).
'$valid_unknown_handler'(V,_) :-
var(V), !,
'$do_error'(instantiation_error,yap_flag(unknown,V)).
'$valid_unknown_handler'(fail,_) :- !.
'$valid_unknown_handler'(error,_) :- !.
'$valid_unknown_handler'(warning,_) :- !.
'$valid_unknown_handler'(S,M) :-
functor(S,_,1),
arg(1,S,A),
var(A),
\+ '$undefined'(S,M),
!.
'$valid_unknown_handler'(S,_) :-
'$do_error'(domain_error(flag_value,unknown+S),yap_flag(unknown,S)).
'$ask_unknown_flag'(Old) :-
recorded('$unknown','$unkonwn'(_,MyOld),_), !,
'$cleanup_unknwon_handler'(MyOld,Old).
'$ask_unknown_flag'(fail).
'$cleanup_unknown_handler'('$unknown_error'(_),error) :- !.
'$cleanup_unknown_handler'('$unknown_warning'(_),warning) :- !.
'$cleanup_unknown_handler'(Handler, Handler).
'$new_unknown'(fail,_) :- !.
'$new_unknown'(error,_) :- !,
recorda('$unknown','$unknown'(P,'$unknown_error'(P)),_).
'$new_unknown'(warning,_) :- !,
recorda('$unknown','$unknown'(P,'$unknown_warning'(P)),_).
'$new_unknown'(X,M) :-
arg(1,X,A),
recorda('$unknown','$unknown'(A,M:X),_).
'$unknown_error'(Mod:Goal) :-
functor(Goal,Name,Arity),
'$program_continuation'(PMod,PName,PAr),
'$do_error'(existence_error(procedure,Name/Arity),context(Mod:Goal,PMod:PName/PAr)).
'$unknown_warning'(Mod:Goal) :-
functor(Goal,Name,Arity),
'$program_continuation'(PMod,PName,PAr),
print_message(error,error(existence_error(procedure,Name/Arity), context(Mod:Goal,PMod:PName/PAr))),
fail.
%%% Some "dirty" predicates
% Only efective if yap compiled with -DDEBUG
% this predicate shows the code produced by the compiler
'$show_code' :- '$debug'(0'f). %' just make emacs happy
grow_heap(X) :- '$grow_heap'(X).
grow_stack(X) :- '$grow_stack'(X).
%
% gc() expects to be called from "call". Make sure it has an
% environment to return to.
%
%garbage_collect :- save(dump), '$gc', save(dump2).
garbage_collect :-
'$gc'.
gc :-
yap_flag(gc,on).
nogc :-
yap_flag(gc,off).
garbage_collect_atoms :-
'$atom_gc'.
'$force_environment_for_gc'.
'$good_list_of_character_codes'(V) :- var(V), !.
'$good_list_of_character_codes'([]).
'$good_list_of_character_codes'([X|L]) :-
'$good_character_code'(X),
'$good_list_of_character_codes'(L).
'$good_character_code'(X) :- var(X), !.
'$good_character_code'(X) :- integer(X), X > -2, X < 256.
atom_concat(X,Y,At) :-
(
nonvar(X), nonvar(Y)
->
atom_concat([X,Y],At)
;
atom(At) ->
atom_length(At,Len),
'$atom_contact_split'(At,0,Len,X,Y)
;
var(At) ->
'$do_error'(instantiation_error,atom_concat(X,Y,At))
;
'$do_error'(type_error(atom,At),atomic_concant(X,Y,At))
).
atomic_concat(X,Y,At) :-
(
nonvar(X), nonvar(Y)
->
atomic_concat([X,Y],At)
;
atom(At) ->
atom_length(At,Len),
'$atom_contact_split'(At,0,Len,X,Y)
;
number(At) ->
number_codes(At,Codes),
lists:append(X0,Y0,Codes),
name(X,X0),
name(Y,Y0)
;
var(At) ->
'$do_error'(instantiation_error,atomic_concat(X,Y,At))
;
'$do_error'(type_error(atomic,At),atomic_concant(X,Y,At))
).
'$atom_contact_split'(At,Len,Len,X,Y) :- !,
'$atom_split'(At,Len,X,Y).
'$atom_contact_split'(At,Len1,_,X,Y) :-
'$atom_split'(At,Len1,X,Y).
'$atom_contact_split'(At,Len1,Len,X,Y) :-
Len2 is Len1+1,
'$atom_contact_split'(At,Len2,Len,X,Y).
sub_atom(At, Bef, Size, After, SubAt) :-
% extract something from an atom
atom(At), integer(Bef), integer(Size), !,
'$sub_atom_extract'(At, Bef, Size, After, SubAt).
sub_atom(At, Bef, Size, After, SubAt) :-
atom(At), !,
atom_codes(At, Atl),
'$sub_atom2'(Bef, Atl, Size, After, SubAt, sub_atom(At, Bef, Size, After, SubAt)).
sub_atom(At, Bef, Size, After, SubAt) :-
var(At), !,
'$do_error'(instantiation_error,sub_atom(At, Bef, Size,After, SubAt)).
sub_atom(At, Bef, Size, After, SubAt) :-
\+ atom(At), !,
'$do_error'(type_error(atom,At),sub_atom(At, Bef, Size,After, SubAt)).
'$sub_atom2'(Bef, Atl, Size, After, SubAt, ErrorTerm) :-
var(Bef), !,
'$sub_atombv'(Bef, Size, After, SubAt, Atl, ErrorTerm).
'$sub_atom2'(Bef, Atl, Size, After, SubAt, ErrorTerm) :-
'$sub_atom_get_subchars'(Bef, Atl, NewAtl),
'$sub_atom3'(Size, After, SubAt, NewAtl, ErrorTerm).
% if SubAt is bound, the rest is deterministic.
'$sub_atom3'(Size, After, SubAt, Atl, ErrorTerm) :-
nonvar(SubAt), !,
'$sub_atom_needs_atom'(SubAt,ErrorTerm),
'$sub_atom_needs_int'(Size,ErrorTerm),
'$sub_atom_needs_int'(After,ErrorTerm),
atom_codes(SubAt,Atls),
'$$_length1'(Atls, 0, Size),
'$sub_atom_get_subchars_and_match'(Size, Atl, Atls, NAtl),
'$$_length1'(NAtl,0,After).
% SubAt is unbound, but Size is bound
'$sub_atom3'(Size, After, SubAt, Atl, ErrorTerm) :-
nonvar(Size), !,
'$sub_atom_needs_int'(Size,ErrorTerm),
'$sub_atom_needs_int'(After,ErrorTerm),
'$sub_atom_get_subchars_and_match'(Size, Atl, SubAts, NAtl),
'$$_length1'(NAtl,0,After),
atom_codes(SubAt,SubAts).
% SubAt and Size are unbound, but After is bound.
'$sub_atom3'(Size, After, SubAt, Atl, ErrorTerm) :-
nonvar(After), !,
'$sub_atom_needs_int'(After,ErrorTerm),
'$sub_atom_get_last_subchars'(Atl,SubAts,After,Total,Size),
Total >= After,
atom_codes(SubAt,SubAts).
% SubAt, Size, and After are unbound.
'$sub_atom3'(Size, After, SubAt, Atl, _) :-
'$$_length1'(Atl,0,Len),
'$sub_atom_split'(Atl,Len,SubAts,Size,_,After),
atom_codes(SubAt,SubAts).
% Bef is unbound, so we've got three hypothesis
% ok: in the best case we just try to find SubAt in the original atom.
'$sub_atombv'(Bef, Size, After, SubAt, Atl, ErrorTerm) :-
nonvar(SubAt), !,
'$sub_atom_needs_atom'(SubAt, ErrorTerm),
atom_codes(SubAt,SubAts),
'$sub_atom_search'(SubAts, Atl, 0, Bef, AfterS),
'$$_length1'(SubAts, 0, Size),
'$$_length1'(AfterS, 0, After).
% ok: in the second best case we just get rid of the tail
'$sub_atombv'(Bef, Size, After, SubAt, Atl, ErrorTerm) :-
nonvar(After), !,
'$sub_atom_needs_int'(After, ErrorTerm),
'$sub_atom_get_last_subchars'(Atl,SubAt0,After,Total,Size0),
Total >= After,
'$sub_atom_split'(SubAt0,Size0,_,Bef,SubAts,Size),
atom_codes(SubAt,SubAts).
% ok: just do everything
'$sub_atombv'(Bef, Size, After, SubAt, Atl, _) :-
'$$_length1'(Atl, 0, Len),
'$sub_atom_split'(Atl,Len,_,Bef,Atls2,Len2),
'$sub_atom_split'(Atls2,Len2,SubAts,Size,_,After),
atom_codes(SubAt,SubAts).
'$sub_atom_search'([], AfterS, BefSize, BefSize, AfterS).
'$sub_atom_search'([C|SubAts], [C|Atl], BefSize, BefSize, AfterS) :-
'$sub_atom_search2'(SubAts, Atl, AfterS).
'$sub_atom_search'([C|SubAts], [_|Atl], BefSize, BefSizeF, AfterS) :-
NBefSize is BefSize+1,
'$sub_atom_search'([C|SubAts], Atl, NBefSize, BefSizeF, AfterS).
'$sub_atom_search2'([], AfterS, AfterS).
'$sub_atom_search2'([C|SubAts], [C|Atl], AfterS) :-
'$sub_atom_search2'(SubAts, Atl, AfterS).
'$sub_atom_get_subchars'(0, Atl, Atl) :- !.
'$sub_atom_get_subchars'(I0, [_|Atl], NAtl) :-
I is I0-1,
'$sub_atom_get_subchars'(I, Atl, NAtl).
'$sub_atom_get_subchars'(0, Atl, [], Atl) :- !.
'$sub_atom_get_subchars'(I0, [C|Atl], [C|L], NAtl) :-
I is I0-1,
'$sub_atom_get_subchars'(I, Atl, L, NAtl).
'$sub_atom_get_subchars_and_match'(0, Atl, [], Atl) :- !.
'$sub_atom_get_subchars_and_match'(I0, [C|Atl], [C|Match], NAtl) :-
I is I0-1,
'$sub_atom_get_subchars_and_match'(I, Atl, Match, NAtl).
'$sub_atom_check_length'([],0).
'$sub_atom_check_length'([_|L],N1) :-
N1 > 0,
N is N1-1,
'$sub_atom_check_length'(L,N).
'$sub_atom_get_last_subchars'([],[],_,0,0).
'$sub_atom_get_last_subchars'([C|Atl],SubAt,After,Total,Size) :-
'$sub_atom_get_last_subchars'(Atl,SubAt0,After,Total0,Size0),
Total is Total0+1,
( Total > After ->
Size is Size0+1, SubAt = [C|SubAt0]
;
Size = Size0, SubAt = SubAt0
).
'$sub_atom_split'(Atl,After,[],0,Atl,After).
'$sub_atom_split'([C|Atl],Len,[C|Atls],Size,NAtl,After) :-
Len1 is Len-1,
'$sub_atom_split'(Atl,Len1,Atls,Size0,NAtl,After),
Size is Size0+1.
'$sub_atom_needs_int'(V,_) :- var(V), !.
'$sub_atom_needs_int'(I,_) :- integer(I), I >= 0, !.
'$sub_atom_needs_int'(I,ErrorTerm) :- integer(I), !,
'$do_error'(domain_error(not_less_than_zero,I),ErrorTerm).
'$sub_atom_needs_int'(I,ErrorTerm) :-
'$do_error'(type_error(integer,I),ErrorTerm).
'$sub_atom_needs_atom'(V,_) :- var(V), !.
'$sub_atom_needs_atom'(A,_) :- atom(A), !.
'$sub_atom_needs_atom'(A,ErrorTerm) :-
'$do_error'(type_error(atom,A),ErrorTerm).
'$singletons_in_term'(T,VL) :-
'$variables_in_term'(T,[],V10),
'$sort'(V10, V1),
'$non_singletons_in_term'(T,[],V20),
'$sort'(V20, V2),
'$subtract_lists_of_variables'(V2,V1,VL).
'$subtract_lists_of_variables'([],VL,VL).
'$subtract_lists_of_variables'([_|_],[],[]) :- !.
'$subtract_lists_of_variables'([V1|VL1],[V2|VL2],VL) :-
V1 == V2, !,
'$subtract_lists_of_variables'(VL1,VL2,VL).
'$subtract_lists_of_variables'([V1|VL1],[V2|VL2],[V2|VL]) :-
'$subtract_lists_of_variables'([V1|VL1],VL2,VL).
simple(V) :- var(V), !.
simple(A) :- atom(A), !.
simple(N) :- number(N).
callable(V) :- var(V), !, fail.
callable(V) :- atom(V), !.
callable(V) :- functor(V,_,Ar), Ar > 0.
initialization :-
'$initialisation_goals'.
prolog_initialization(G) :- var(G), !,
'$do_error'(instantiation_error,initialization(G)).
prolog_initialization(T) :- callable(T), !,
'$assert_init'(T).
prolog_initialization(T) :-
'$do_error'(type_error(callable,T),initialization(T)).
'$assert_init'(T) :- recordz('$startup_goal',T,_), fail.
'$assert_init'(_).
version :- '$version'.
version(V) :- var(V), !,
'$do_error'(instantiation_error,version(V)).
version(T) :- atom(T), !, '$assert_version'(T).
version(T) :-
'$do_error'(type_error(atom,T),version(T)).
'$assert_version'(T) :- recordz('$version',T,_), fail.
'$assert_version'(_).
'$set_toplevel_hook'(_) :-
recorded('$toplevel_hooks',_,R),
erase(R),
fail.
'$set_toplevel_hook'(H) :-
recorda('$toplevel_hooks',H,_),
fail.
'$set_toplevel_hook'(_).
halt(X) :- '$halt'(X).
halt :-
print_message(informational, halt),
'$halt'(0).
halt(X) :-
'$halt'(X).
nth_instance(X,Y,Z) :-
nonvar(X), var(Y), var(Z), !,
recorded(X,_,Z),
'$nth_instance'(_,Y,Z).
nth_instance(X,Y,Z) :-
'$nth_instance'(X,Y,Z).
'$run_atom_goal'(GA) :-
'$current_module'(Module),
atom_codes(GA,Gs0),
'$add_dot_to_atom_goal'(Gs0,Gs),
charsio:open_mem_read_stream(Gs, Stream),
( '$system_catch'(read(Stream, G),Module,_,fail) ->
close(Stream)
;
close(Stream),
fail
),
'$system_catch'('$query'(once(G), []),Module,Error,user:'$Error'(Error)).
'$add_dot_to_atom_goal'([],[0'.]) :- !.
'$add_dot_to_atom_goal'([0'.],[0'.]) :- !.
'$add_dot_to_atom_goal'([C|Gs0],[C|Gs]) :-
'$add_dot_to_atom_goal'(Gs0,Gs).
prolog_current_frame(Env) :-
Env is '$env'.
nb_current(GlobalVariable, Val) :-
var(GlobalVariable), !,
'$nb_current'(GlobalVariable),
nb_getval(GlobalVariable, Val).
nb_current(GlobalVariable, Val) :-
nb_getval(GlobalVariable, Val).