const synfig::Canvas::LooseHandle& get_canvas()const { assert(type_==TYPE_CANVAS); return data.canvas.get(); }
const etl::loose_handle<synfigapp::CanvasInterface>& get_canvas_interface()const { assert(type_==TYPE_CANVASINTERFACE); return data.canvas_interface.get(); }
const synfig::Layer::LooseHandle& get_layer()const { assert(type_==TYPE_LAYER); return data.layer.get(); }
const synfig::Canvas::LooseHandle& get_canvas()const { assert(type_==TYPE_CANVAS); return data.canvas.get(); }
const etl::loose_handle<synfigapp::CanvasInterface>& get_canvas_interface()const { assert(type_==TYPE_CANVASINTERFACE); return data.canvas_interface.get(); }
const synfig::Layer::LooseHandle& get_layer()const { assert(type_==TYPE_LAYER); return data.layer.get(); }