boost::weak_ptr<Route> wr ((*x)->route());
(*x)->route()->gui_changed.connect (*this, MISSING_INVALIDATOR, boost::bind (&EditorRoutes::handle_gui_changes, this, _1, _2), gui_context());
boost::weak_ptr<Route> wr ((*x)->route());
(*x)->route()->gui_changed.connect (*this, MISSING_INVALIDATOR, boost::bind (&EditorRoutes::handle_gui_changes, this, _1, _2), gui_context());