Function through_post

examples/example-asio/example-asio-integration.cpp:155–159

template <typename T>
auto through_post(T& postable) {
  return [&postable](auto&& work) mutable {
    asio::post(postable, std::forward<decltype(work)>(work));
  };
}

void using_strand() {
  asio::io_context ioc(1);