当我打开SWI-Prolog并输入命令＆＃34; list。＆＃34;它应该只返回yes并且在咨询知识库之后，它应该只返回谓词而不是它返回：
?- listing.
:- dynamic exception/3.
:- multifile exception/3.
:- multifile prolog_clause_name/2.
:- multifile prolog_predicate_name/2.
:- dynamic library_directory/1.
:- multifile library_directory/1.
library_directory(B) :-
'$parms':
( cached_library_directory(local, A=lib, A),
B=A
).
library_directory(B) :-
'$parms':
( cached_library_directory(user,
expand_file_name('~/lib/prolog', [A]),
A),
B=A
).
library_directory(B) :-
'$parms':
( cached_library_directory(system,
absolute_file_name(swi(library), A),
A),
B=A
).
library_directory(B) :-
'$parms':
( cached_library_directory(clp,
absolute_file_name(swi('library/clp'), A),
A),
B=A
).
:- thread_local thread_message_hook/3.
:- dynamic thread_message_hook/3.
:- volatile thread_message_hook/3.
:- dynamic expand_answer/2.
:- multifile expand_answer/2.
:- dynamic file_search_path/2.
:- multifile file_search_path/2.
file_search_path(library, A) :-
library_directory(A).
file_search_path(swi, A) :-
system:current_prolog_flag(home, A).
file_search_path(foreign, swi(B)) :-
system:
( current_prolog_flag(arch, A),
atom_concat('lib/', A, B)
).
file_search_path(foreign, swi(A)) :-
system:
( ( current_prolog_flag(windows, true)
-> A=bin
; A=lib
)
).
file_search_path(path, C) :-
system:
( getenv('PATH', A),
( current_prolog_flag(windows, true)
-> atomic_list_concat(B, ;, A)
; atomic_list_concat(B, :, A)
),
'$member'(C, B),
'$no-null-bytes'(C)
).
file_search_path(user_profile, app_preferences('.')).
file_search_path(app_preferences, app_data('.')).
file_search_path(app_data, B) :-
'$toplevel':
( current_prolog_flag(windows, true),
catch(win_folder(appdata, A), _, fail),
atom_concat(A, '/SWI-Prolog', B),
( exists_directory(B)
-> true
; catch(make_directory(B), _, fail)
)
).
file_search_path(app_preferences, A) :-
'$toplevel':catch(expand_file_name(~, [A]), _, fail).
file_search_path(autoload, library('.')).
file_search_path(pack, app_data(pack)).
file_search_path(pack, swi(pack)).
file_search_path(library, A) :-
'$pack':pack_dir(_, prolog, A).
file_search_path(foreign, A) :-
'$pack':pack_dir(_, foreign, A).
file_search_path(pce, A) :-
link_xpce:pcehome_(A).
file_search_path(library, pce('prolog/lib')).
file_search_path(foreign, pce(B)) :-
link_xpce:
( current_prolog_flag(arch, A),
atom_concat('lib/', A, B)
).
:- dynamic message_hook/3.
:- multifile message_hook/3.
:- dynamic prolog_event_hook/1.
:- multifile prolog_event_hook/1.
:- multifile prolog_list_goal/1.
:- dynamic prolog_exception_hook/4.
:- multifile prolog_exception_hook/4.
prolog_exception_hook(error(A, context(D, B)), error(A, context(prolog_stack(J), B)), G, C) :-
prolog_stack:
( current_prolog_flag(backtrace, true),
( atom(C)
-> debug(backtrace,
'Got uncaught (guard = ~q) exception ~p (Ctx0=~p)',
[C, A, D]),
stack_guard(C)
; prolog_frame_attribute(C, predicate_indicator, E),
debug(backtrace,
'Got exception ~p (Ctx0=~p, Catcher=~p)',
[A, D, E]),
stack_guard(E)
),
( current_prolog_flag(backtrace_depth, F)
-> F>0
; F=20
),
get_prolog_backtrace(G, F, H),
debug(backtrace, 'Stack = ~p', [H]),
clean_stack(H, I),
join_stacks(D, I, J)
).
:- multifile message_property/2.
:- dynamic prolog_load_file/2.
:- multifile prolog_load_file/2.
:- dynamic portray/1.
:- multifile portray/1.
:- dynamic prolog_file_type/2.
:- multifile prolog_file_type/2.
prolog_file_type(pl, prolog).
prolog_file_type(prolog, prolog).
prolog_file_type(qlf, prolog).
prolog_file_type(qlf, qlf).
prolog_file_type(A, executable) :-
system:current_prolog_flag(shared_object_extension, A).
:- dynamic resource/3.
:- multifile resource/3.
:- dynamic expand_query/4.
:- multifile expand_query/4.
true.
为什么它会返回此而不是真/是？我似乎无法在网上找到答案。当我在咨询知识库之后给出列表命令时，它给出了类似的响应，除了长篇中间的谓词。还列出/ 1和列出/ 0等...只是给出错误（也是在咨询知识库之后。
克