template <typename T>
void tgroup::execute_group_actions(T& caller_widget)
{
    FOREACH(AUTO * widget, members_)
    {
        if(widget == NULL) {
            continue;
        }

        //
        // NOTE: optimally, we would use virtual functions to enforce the
        // function mame, but since this is only used by one widget so far,
        // it seems a waste to add a pure virtual method to twidget and override
        // it in every widget class save one.
        //
        // TODO: investigate cleaner usecase in future
        //
        caller_widget->group_operator(dynamic_cast<T>(widget));
    }
}