Function async_wait_twice

example/cpp14/deferred/deferred_5.cpp:17–43

template <typename CompletionToken>
auto async_wait_twice(boost::asio::steady_timer& timer, CompletionToken&& token)
{
  return timer.async_wait(
      deferred(
        [&](boost::system::error_code ec)
        {
          std::cout << "first timer wait finished: " << ec.message() << "\n";
          timer.expires_after(std::chrono::seconds(1));
          return deferred.when(!ec)
            .then(timer.async_wait(deferred))
            .otherwise(deferred.values(ec));
        }
      )
    )(
      deferred(
        [&](boost::system::error_code ec)
        {
          std::cout << "second timer wait finished: " << ec.message() << "\n";
          return deferred.when(!ec)
            .then(deferred.values(42))
            .otherwise(deferred.values(0));
        }
      )
    )(
      std::forward<CompletionToken>(token)
    );
}

int main()
{