const int delta = event->pos().y() - _mouse_down_point.y();
- for (std::list<std::pair<boost::weak_ptr<Trace>,
- int> >::iterator i = _drag_traces.begin();
- i != _drag_traces.end(); i++) {
+ for (auto i = _drag_traces.begin(); i != _drag_traces.end(); i++) {
const boost::shared_ptr<Trace> trace((*i).first);
if (trace) {
const int y = (*i).second + delta;