must_det_ll1(P1,X):- tracing,!,must_not_error(call(P1,X)),!.
must_det_ll1(P1,once(A)):- !, once(md(P1,A)).
must_det_ll1(P1,X):-
  strip_module(X,M,P),functor(P,F,A),
  setup_call_cleanup(nop(trace(M:F/A,+fail)),(must_not_error(call(P1,X))*->true;md_failed(P1,X)),
    nop(trace(M:F/A,-fail))),!.


%must_not_error(G):- must(once(G)).

must_not_error(G):- (tracing;never_rrtrace),!,call(G).
must_not_error(G):- notrace(is_cgi),!, ncatch((G),E,((u_dmsg(E=G)))).
%must_not_error(X):- is_guitracer,!, call(X).
%must_not_error(G):- !, call(G).
must_not_error(X):- !,ncatch(X,E,(fbug(E=X),ugtrace(error(E),X))).
must_not_error(X):- ncatch(X,E,(rethrow_abort(E);(/*arcST,*/writeq(E=X),pp(etrace=X),
  trace,
  rrtrace(visible_rtrace([-all,+exception]),X)))).


always_rethrow('$aborted').
always_rethrow(md_failed(_,_,_)).
always_rethrow(return(_)).
always_rethrow(metta_return(_)).
always_rethrow(give_up(_)).
always_rethrow(time_limit_exceeded(_)).
always_rethrow(depth_limit_exceeded).
always_rethrow(restart_reading).
always_rethrow(E):- never_rrtrace,!,throw(E).

%catch_non_abort(Goal):- cant_rrtrace(Goal).
catch_non_abort(Goal):- catch(cant_rrtrace(Goal),E,rethrow_abort(E)),!.
rethrow_abort(E):- format(user_error,'~N~q~n',[catch_non_abort_or_abort(E)]),fail.
%rethrow_abort(time_limit_exceeded):-!.
rethrow_abort('$aborted'):- !, throw('$aborted'),!,forall(between(1,700,_),sleep(0.01)),writeln(timeout),!,fail.
rethrow_abort(E):- ds,!,format(user_error,'~N~q~n',[catch_non_abort(E)]),!.

cant_rrtrace(Goal):- never_rrtrace,!,call(Goal).
cant_rrtrace(Goal):- setup_call_cleanup(cant_rrtrace,Goal,can_rrtrace).

main_debug:- main_thread,current_prolog_flag(debug,true).
cant_rrtrace:- nb_setval(cant_rrtrace,t).
can_rrtrace:- nb_setval(cant_rrtrace,f).
%md_failed(P1,X):- predicate_property(X,number_of_clauses(1)),clause(X,(A,B,C,Body)), (B\==!),!,must_det_ll(A),must_det_ll((B,C,Body)).

md_failed(P1,X):- notrace((write_src_uo(failed(P1,X)),fail)).
md_failed(P1,X):- tracing,visible_rtrace([-all,+fail,+call,+exception],call(P1,X)).
md_failed(P1,X):- \+ tracing, !, visible_rtrace([-all,+fail,+exit,+call,+exception],call(P1,X)).
md_failed(P1,G):- is_cgi, \+ main_debug, !, u_dmsg(arc_html(md_failed(P1,G))),fail.
md_failed(_P1,G):- option_value(testing,true),!,
      T='FAILEDDDDDDDDDDDDDDDDDDDDDDDDDD!!!!!!!!!!!!!'(G),
      write_src_uo(T), give_up(T,G).
md_failed(P1,G):- never_rrtrace,!,notrace,/*notrace*/(u_dmsg(md_failed(P1,G))),!,throw(md_failed(P1,G,2)).
%md_failed(P1,G):- tracing,call(P1,G).
md_failed(_,_):- never_rrtrace,!,fail.
md_failed(P1,X):- notrace,is_guitracer,u_dmsg(failed(X))/*,arcST*/,nortrace,atrace,call(P1,X).
md_failed(P1,G):- main_debug,/*notrace*/(write_src_uo(md_failed(P1,G))),!,throw(md_failed(P1,G,2)).
% must_det_ll(X):- must_det_ll(X),!.

write_src_uo(G):-
 stream_property(S,file_no(1)),
    with_output_to(S,
     (format('~N~n~n',[]),
      write_src(G),