anchor.diff:                          {Predecessor, _Initial} =
                               find_preds_and_initials(Lid, ProcSI, Candidates,
                                                       I, ClockVector, Acc),
  -                        case
  -                            decide_classic(Predecessor, Backtrack, Candidates,
  -                                           PreSI)
  -                        of
  -                            {done, _} = DoneResult -> DoneResult;
  -                            continue ->
  -                                NewClockVector =
  -                                    lookup_clock(ProcSI, ClockMap),
  -                                MaxClockVector =
  -                                    max_cv(NewClockVector, ClockVector),
  -                                {continue_source, ProcSI, MaxClockVector}
  -                        end
  +                        decide_classic(Predecessor, Backtrack, Candidates,
  +                                       PreSI)
                   end
           end,
       case Action of
  
positive.code:                                                                  Backtrack)),
                                      case
                                          Flavor =:= ?FULL orelse
                                          Flavor =:= none
                                      of
                                          true -> NB;
  
negative.code:             ?debug("One pred already in backtrack.\n"),
              {done, PreSI};
          false ->
              Added =
                  case Predecessor of
                      [OneP] ->
                          ?debug(" Add as 'choose-one': ~p\n", [OneP]),
                          [{OneP, dummy, []}];
                      [] ->
                          ?debug(" Add as 'choose every': ~p\n", [Candidates]),
                          New = ordsets:subtract(Candidates, BacktrackSet),
                          [{P, dummy, []} || P <- New]
                  end,
              ?debug("    Added: ~p\n",[Added]),
              {done, PreSI#trace_state{backtrack = Backtrack ++ Added}}
      end.
  
  %% --------------------------------------
  