template <typename Sig, typename E, typename F> auto package_with_broken_promise(E executor, F && f) -> std::pair<detail::packaged_task_from_signature_t<Sig>, future<detail::result_of_t_<Sig>>> (1) template <typename Signature, typename E, typename F> auto package_with_broken_promise(E, F &&) -> std::pair<detail::packaged_task_from_signature_t<Signature>, future<detail::result_of_t_<Signature>>> (2) (1) template <typename Sig, typename E, typename F> auto package_with_broken_promise(E executor, F && f) -> std::pair<detail::packaged_task_from_signature_t<Sig>, future<detail::result_of_t_<Sig>>> MISSING Parameters E executor F && f (2) template <typename Signature, typename E, typename F> auto package_with_broken_promise(E, F &&) -> std::pair<detail::packaged_task_from_signature_t<Signature>, future<detail::result_of_t_<Signature>>> MISSING Parameters E unnamed F && unnamed