0;    for(const auto &step : goto_trace.steps)   {     // hide the hidden ones     if(step.hidden)       continue;      switch(step.type)     {     case goto_trace_stept::typet::ASSERT:       if(!step.cond_value)       {         out << '\n';         out << messaget::red << "Violated property:" << messaget::reset << '\n';         if(!step.pc->source_location.is_nil())         