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92f5a8d4 TL |
1 | // |
2 | // co_spawn.hpp | |
3 | // ~~~~~~~~~~~~ | |
4 | // | |
1e59de90 | 5 | // Copyright (c) 2003-2022 Christopher M. Kohlhoff (chris at kohlhoff dot com) |
92f5a8d4 TL |
6 | // |
7 | // Distributed under the Boost Software License, Version 1.0. (See accompanying | |
8 | // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) | |
9 | // | |
10 | ||
11 | #ifndef BOOST_ASIO_CO_SPAWN_HPP | |
12 | #define BOOST_ASIO_CO_SPAWN_HPP | |
13 | ||
14 | #if defined(_MSC_VER) && (_MSC_VER >= 1200) | |
15 | # pragma once | |
16 | #endif // defined(_MSC_VER) && (_MSC_VER >= 1200) | |
17 | ||
18 | #include <boost/asio/detail/config.hpp> | |
19 | ||
20 | #if defined(BOOST_ASIO_HAS_CO_AWAIT) || defined(GENERATING_DOCUMENTATION) | |
21 | ||
22 | #include <boost/asio/awaitable.hpp> | |
20effc67 | 23 | #include <boost/asio/execution/executor.hpp> |
92f5a8d4 TL |
24 | #include <boost/asio/execution_context.hpp> |
25 | #include <boost/asio/is_executor.hpp> | |
26 | ||
27 | #include <boost/asio/detail/push_options.hpp> | |
28 | ||
29 | namespace boost { | |
30 | namespace asio { | |
31 | namespace detail { | |
32 | ||
33 | template <typename T> | |
34 | struct awaitable_signature; | |
35 | ||
36 | template <typename T, typename Executor> | |
37 | struct awaitable_signature<awaitable<T, Executor>> | |
38 | { | |
39 | typedef void type(std::exception_ptr, T); | |
40 | }; | |
41 | ||
42 | template <typename Executor> | |
43 | struct awaitable_signature<awaitable<void, Executor>> | |
44 | { | |
45 | typedef void type(std::exception_ptr); | |
46 | }; | |
47 | ||
48 | } // namespace detail | |
49 | ||
20effc67 | 50 | /// Spawn a new coroutined-based thread of execution. |
92f5a8d4 | 51 | /** |
20effc67 TL |
52 | * @param ex The executor that will be used to schedule the new thread of |
53 | * execution. | |
92f5a8d4 | 54 | * |
20effc67 TL |
55 | * @param a The boost::asio::awaitable object that is the result of calling the |
56 | * coroutine's entry point function. | |
92f5a8d4 | 57 | * |
1e59de90 | 58 | * @param token The @ref completion_token that will handle the notification that |
20effc67 TL |
59 | * the thread of execution has completed. The function signature of the |
60 | * completion handler must be: | |
61 | * @code void handler(std::exception_ptr, T); @endcode | |
62 | * | |
1e59de90 TL |
63 | * @par Completion Signature |
64 | * @code void(std::exception_ptr, T) @endcode | |
65 | * | |
20effc67 TL |
66 | * @par Example |
67 | * @code | |
68 | * boost::asio::awaitable<std::size_t> echo(tcp::socket socket) | |
69 | * { | |
70 | * std::size_t bytes_transferred = 0; | |
71 | * | |
72 | * try | |
73 | * { | |
74 | * char data[1024]; | |
75 | * for (;;) | |
76 | * { | |
77 | * std::size_t n = co_await socket.async_read_some( | |
78 | * boost::asio::buffer(data), boost::asio::use_awaitable); | |
79 | * | |
80 | * co_await boost::asio::async_write(socket, | |
81 | * boost::asio::buffer(data, n), boost::asio::use_awaitable); | |
82 | * | |
83 | * bytes_transferred += n; | |
84 | * } | |
85 | * } | |
86 | * catch (const std::exception&) | |
87 | * { | |
88 | * } | |
89 | * | |
90 | * co_return bytes_transferred; | |
91 | * } | |
92 | * | |
93 | * // ... | |
94 | * | |
95 | * boost::asio::co_spawn(my_executor, | |
96 | * echo(std::move(my_tcp_socket)), | |
97 | * [](std::exception_ptr e, std::size_t n) | |
98 | * { | |
99 | * std::cout << "transferred " << n << "\n"; | |
100 | * }); | |
101 | * @endcode | |
1e59de90 TL |
102 | * |
103 | * @par Per-Operation Cancellation | |
104 | * The new thread of execution is created with a cancellation state that | |
105 | * supports @c cancellation_type::terminal values only. To change the | |
106 | * cancellation state, call boost::asio::this_coro::reset_cancellation_state. | |
20effc67 TL |
107 | */ |
108 | template <typename Executor, typename T, typename AwaitableExecutor, | |
109 | BOOST_ASIO_COMPLETION_TOKEN_FOR( | |
110 | void(std::exception_ptr, T)) CompletionToken | |
111 | BOOST_ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(Executor)> | |
112 | inline BOOST_ASIO_INITFN_AUTO_RESULT_TYPE( | |
113 | CompletionToken, void(std::exception_ptr, T)) | |
114 | co_spawn(const Executor& ex, awaitable<T, AwaitableExecutor> a, | |
115 | CompletionToken&& token | |
116 | BOOST_ASIO_DEFAULT_COMPLETION_TOKEN(Executor), | |
1e59de90 | 117 | typename constraint< |
20effc67 TL |
118 | (is_executor<Executor>::value || execution::is_executor<Executor>::value) |
119 | && is_convertible<Executor, AwaitableExecutor>::value | |
1e59de90 | 120 | >::type = 0); |
20effc67 TL |
121 | |
122 | /// Spawn a new coroutined-based thread of execution. | |
123 | /** | |
124 | * @param ex The executor that will be used to schedule the new thread of | |
125 | * execution. | |
126 | * | |
127 | * @param a The boost::asio::awaitable object that is the result of calling the | |
128 | * coroutine's entry point function. | |
129 | * | |
1e59de90 | 130 | * @param token The @ref completion_token that will handle the notification that |
20effc67 TL |
131 | * the thread of execution has completed. The function signature of the |
132 | * completion handler must be: | |
133 | * @code void handler(std::exception_ptr); @endcode | |
134 | * | |
1e59de90 TL |
135 | * @par Completion Signature |
136 | * @code void(std::exception_ptr) @endcode | |
137 | * | |
20effc67 TL |
138 | * @par Example |
139 | * @code | |
140 | * boost::asio::awaitable<void> echo(tcp::socket socket) | |
141 | * { | |
142 | * try | |
143 | * { | |
144 | * char data[1024]; | |
145 | * for (;;) | |
146 | * { | |
147 | * std::size_t n = co_await socket.async_read_some( | |
148 | * boost::asio::buffer(data), boost::asio::use_awaitable); | |
149 | * | |
150 | * co_await boost::asio::async_write(socket, | |
151 | * boost::asio::buffer(data, n), boost::asio::use_awaitable); | |
152 | * } | |
153 | * } | |
154 | * catch (const std::exception& e) | |
155 | * { | |
156 | * std::cerr << "Exception: " << e.what() << "\n"; | |
157 | * } | |
158 | * } | |
159 | * | |
160 | * // ... | |
161 | * | |
162 | * boost::asio::co_spawn(my_executor, | |
163 | * echo(std::move(my_tcp_socket)), | |
164 | * boost::asio::detached); | |
165 | * @endcode | |
1e59de90 TL |
166 | * |
167 | * @par Per-Operation Cancellation | |
168 | * The new thread of execution is created with a cancellation state that | |
169 | * supports @c cancellation_type::terminal values only. To change the | |
170 | * cancellation state, call boost::asio::this_coro::reset_cancellation_state. | |
20effc67 TL |
171 | */ |
172 | template <typename Executor, typename AwaitableExecutor, | |
173 | BOOST_ASIO_COMPLETION_TOKEN_FOR( | |
174 | void(std::exception_ptr)) CompletionToken | |
175 | BOOST_ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(Executor)> | |
176 | inline BOOST_ASIO_INITFN_AUTO_RESULT_TYPE( | |
177 | CompletionToken, void(std::exception_ptr)) | |
178 | co_spawn(const Executor& ex, awaitable<void, AwaitableExecutor> a, | |
179 | CompletionToken&& token | |
180 | BOOST_ASIO_DEFAULT_COMPLETION_TOKEN(Executor), | |
1e59de90 | 181 | typename constraint< |
20effc67 TL |
182 | (is_executor<Executor>::value || execution::is_executor<Executor>::value) |
183 | && is_convertible<Executor, AwaitableExecutor>::value | |
1e59de90 | 184 | >::type = 0); |
20effc67 TL |
185 | |
186 | /// Spawn a new coroutined-based thread of execution. | |
187 | /** | |
188 | * @param ctx An execution context that will provide the executor to be used to | |
189 | * schedule the new thread of execution. | |
190 | * | |
191 | * @param a The boost::asio::awaitable object that is the result of calling the | |
192 | * coroutine's entry point function. | |
193 | * | |
1e59de90 | 194 | * @param token The @ref completion_token that will handle the notification that |
20effc67 TL |
195 | * the thread of execution has completed. The function signature of the |
196 | * completion handler must be: | |
197 | * @code void handler(std::exception_ptr); @endcode | |
198 | * | |
1e59de90 TL |
199 | * @par Completion Signature |
200 | * @code void(std::exception_ptr, T) @endcode | |
201 | * | |
20effc67 TL |
202 | * @par Example |
203 | * @code | |
204 | * boost::asio::awaitable<std::size_t> echo(tcp::socket socket) | |
205 | * { | |
206 | * std::size_t bytes_transferred = 0; | |
207 | * | |
208 | * try | |
209 | * { | |
210 | * char data[1024]; | |
211 | * for (;;) | |
212 | * { | |
213 | * std::size_t n = co_await socket.async_read_some( | |
214 | * boost::asio::buffer(data), boost::asio::use_awaitable); | |
215 | * | |
216 | * co_await boost::asio::async_write(socket, | |
217 | * boost::asio::buffer(data, n), boost::asio::use_awaitable); | |
218 | * | |
219 | * bytes_transferred += n; | |
220 | * } | |
221 | * } | |
222 | * catch (const std::exception&) | |
223 | * { | |
224 | * } | |
225 | * | |
226 | * co_return bytes_transferred; | |
227 | * } | |
228 | * | |
229 | * // ... | |
230 | * | |
231 | * boost::asio::co_spawn(my_io_context, | |
232 | * echo(std::move(my_tcp_socket)), | |
233 | * [](std::exception_ptr e, std::size_t n) | |
234 | * { | |
235 | * std::cout << "transferred " << n << "\n"; | |
236 | * }); | |
237 | * @endcode | |
1e59de90 TL |
238 | * |
239 | * @par Per-Operation Cancellation | |
240 | * The new thread of execution is created with a cancellation state that | |
241 | * supports @c cancellation_type::terminal values only. To change the | |
242 | * cancellation state, call boost::asio::this_coro::reset_cancellation_state. | |
20effc67 TL |
243 | */ |
244 | template <typename ExecutionContext, typename T, typename AwaitableExecutor, | |
245 | BOOST_ASIO_COMPLETION_TOKEN_FOR( | |
246 | void(std::exception_ptr, T)) CompletionToken | |
247 | BOOST_ASIO_DEFAULT_COMPLETION_TOKEN_TYPE( | |
248 | typename ExecutionContext::executor_type)> | |
249 | inline BOOST_ASIO_INITFN_AUTO_RESULT_TYPE( | |
250 | CompletionToken, void(std::exception_ptr, T)) | |
251 | co_spawn(ExecutionContext& ctx, awaitable<T, AwaitableExecutor> a, | |
252 | CompletionToken&& token | |
253 | BOOST_ASIO_DEFAULT_COMPLETION_TOKEN( | |
254 | typename ExecutionContext::executor_type), | |
1e59de90 | 255 | typename constraint< |
20effc67 TL |
256 | is_convertible<ExecutionContext&, execution_context&>::value |
257 | && is_convertible<typename ExecutionContext::executor_type, | |
258 | AwaitableExecutor>::value | |
1e59de90 | 259 | >::type = 0); |
20effc67 TL |
260 | |
261 | /// Spawn a new coroutined-based thread of execution. | |
262 | /** | |
263 | * @param ctx An execution context that will provide the executor to be used to | |
264 | * schedule the new thread of execution. | |
265 | * | |
266 | * @param a The boost::asio::awaitable object that is the result of calling the | |
267 | * coroutine's entry point function. | |
268 | * | |
1e59de90 | 269 | * @param token The @ref completion_token that will handle the notification that |
20effc67 TL |
270 | * the thread of execution has completed. The function signature of the |
271 | * completion handler must be: | |
272 | * @code void handler(std::exception_ptr); @endcode | |
273 | * | |
1e59de90 TL |
274 | * @par Completion Signature |
275 | * @code void(std::exception_ptr) @endcode | |
276 | * | |
20effc67 TL |
277 | * @par Example |
278 | * @code | |
279 | * boost::asio::awaitable<void> echo(tcp::socket socket) | |
280 | * { | |
281 | * try | |
282 | * { | |
283 | * char data[1024]; | |
284 | * for (;;) | |
285 | * { | |
286 | * std::size_t n = co_await socket.async_read_some( | |
287 | * boost::asio::buffer(data), boost::asio::use_awaitable); | |
288 | * | |
289 | * co_await boost::asio::async_write(socket, | |
290 | * boost::asio::buffer(data, n), boost::asio::use_awaitable); | |
291 | * } | |
292 | * } | |
293 | * catch (const std::exception& e) | |
294 | * { | |
295 | * std::cerr << "Exception: " << e.what() << "\n"; | |
296 | * } | |
297 | * } | |
298 | * | |
299 | * // ... | |
300 | * | |
301 | * boost::asio::co_spawn(my_io_context, | |
302 | * echo(std::move(my_tcp_socket)), | |
303 | * boost::asio::detached); | |
304 | * @endcode | |
1e59de90 TL |
305 | * |
306 | * @par Per-Operation Cancellation | |
307 | * The new thread of execution is created with a cancellation state that | |
308 | * supports @c cancellation_type::terminal values only. To change the | |
309 | * cancellation state, call boost::asio::this_coro::reset_cancellation_state. | |
20effc67 TL |
310 | */ |
311 | template <typename ExecutionContext, typename AwaitableExecutor, | |
312 | BOOST_ASIO_COMPLETION_TOKEN_FOR( | |
313 | void(std::exception_ptr)) CompletionToken | |
314 | BOOST_ASIO_DEFAULT_COMPLETION_TOKEN_TYPE( | |
315 | typename ExecutionContext::executor_type)> | |
316 | inline BOOST_ASIO_INITFN_AUTO_RESULT_TYPE( | |
317 | CompletionToken, void(std::exception_ptr)) | |
318 | co_spawn(ExecutionContext& ctx, awaitable<void, AwaitableExecutor> a, | |
319 | CompletionToken&& token | |
320 | BOOST_ASIO_DEFAULT_COMPLETION_TOKEN( | |
321 | typename ExecutionContext::executor_type), | |
1e59de90 | 322 | typename constraint< |
20effc67 TL |
323 | is_convertible<ExecutionContext&, execution_context&>::value |
324 | && is_convertible<typename ExecutionContext::executor_type, | |
325 | AwaitableExecutor>::value | |
1e59de90 | 326 | >::type = 0); |
20effc67 TL |
327 | |
328 | /// Spawn a new coroutined-based thread of execution. | |
329 | /** | |
330 | * @param ex The executor that will be used to schedule the new thread of | |
331 | * execution. | |
332 | * | |
333 | * @param f A nullary function object with a return type of the form | |
334 | * @c boost::asio::awaitable<R,E> that will be used as the coroutine's entry | |
335 | * point. | |
336 | * | |
1e59de90 TL |
337 | * @param token The @ref completion_token that will handle the notification |
338 | * that the thread of execution has completed. If @c R is @c void, the function | |
20effc67 TL |
339 | * signature of the completion handler must be: |
340 | * | |
341 | * @code void handler(std::exception_ptr); @endcode | |
342 | * Otherwise, the function signature of the completion handler must be: | |
343 | * @code void handler(std::exception_ptr, R); @endcode | |
344 | * | |
1e59de90 TL |
345 | * @par Completion Signature |
346 | * @code void(std::exception_ptr, R) @endcode | |
347 | * where @c R is the first template argument to the @c awaitable returned by the | |
348 | * supplied function object @c F: | |
349 | * @code boost::asio::awaitable<R, AwaitableExecutor> F() @endcode | |
20effc67 TL |
350 | * |
351 | * @par Example | |
352 | * @code | |
353 | * boost::asio::awaitable<std::size_t> echo(tcp::socket socket) | |
354 | * { | |
355 | * std::size_t bytes_transferred = 0; | |
356 | * | |
357 | * try | |
358 | * { | |
359 | * char data[1024]; | |
360 | * for (;;) | |
361 | * { | |
362 | * std::size_t n = co_await socket.async_read_some( | |
363 | * boost::asio::buffer(data), boost::asio::use_awaitable); | |
364 | * | |
365 | * co_await boost::asio::async_write(socket, | |
366 | * boost::asio::buffer(data, n), boost::asio::use_awaitable); | |
367 | * | |
368 | * bytes_transferred += n; | |
369 | * } | |
370 | * } | |
371 | * catch (const std::exception&) | |
372 | * { | |
373 | * } | |
374 | * | |
375 | * co_return bytes_transferred; | |
376 | * } | |
377 | * | |
378 | * // ... | |
379 | * | |
380 | * boost::asio::co_spawn(my_executor, | |
381 | * [socket = std::move(my_tcp_socket)]() mutable | |
382 | * -> boost::asio::awaitable<void> | |
383 | * { | |
384 | * try | |
385 | * { | |
386 | * char data[1024]; | |
387 | * for (;;) | |
388 | * { | |
389 | * std::size_t n = co_await socket.async_read_some( | |
390 | * boost::asio::buffer(data), boost::asio::use_awaitable); | |
391 | * | |
392 | * co_await boost::asio::async_write(socket, | |
393 | * boost::asio::buffer(data, n), boost::asio::use_awaitable); | |
394 | * } | |
395 | * } | |
396 | * catch (const std::exception& e) | |
397 | * { | |
398 | * std::cerr << "Exception: " << e.what() << "\n"; | |
399 | * } | |
400 | * }, boost::asio::detached); | |
401 | * @endcode | |
1e59de90 TL |
402 | * |
403 | * @par Per-Operation Cancellation | |
404 | * The new thread of execution is created with a cancellation state that | |
405 | * supports @c cancellation_type::terminal values only. To change the | |
406 | * cancellation state, call boost::asio::this_coro::reset_cancellation_state. | |
92f5a8d4 TL |
407 | */ |
408 | template <typename Executor, typename F, | |
409 | BOOST_ASIO_COMPLETION_TOKEN_FOR(typename detail::awaitable_signature< | |
410 | typename result_of<F()>::type>::type) CompletionToken | |
411 | BOOST_ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(Executor)> | |
412 | BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, | |
413 | typename detail::awaitable_signature<typename result_of<F()>::type>::type) | |
414 | co_spawn(const Executor& ex, F&& f, | |
415 | CompletionToken&& token | |
416 | BOOST_ASIO_DEFAULT_COMPLETION_TOKEN(Executor), | |
1e59de90 | 417 | typename constraint< |
20effc67 | 418 | is_executor<Executor>::value || execution::is_executor<Executor>::value |
1e59de90 | 419 | >::type = 0); |
92f5a8d4 | 420 | |
20effc67 | 421 | /// Spawn a new coroutined-based thread of execution. |
92f5a8d4 | 422 | /** |
20effc67 TL |
423 | * @param ctx An execution context that will provide the executor to be used to |
424 | * schedule the new thread of execution. | |
425 | * | |
426 | * @param f A nullary function object with a return type of the form | |
427 | * @c boost::asio::awaitable<R,E> that will be used as the coroutine's entry | |
428 | * point. | |
429 | * | |
1e59de90 TL |
430 | * @param token The @ref completion_token that will handle the notification |
431 | * that the thread of execution has completed. If @c R is @c void, the function | |
20effc67 TL |
432 | * signature of the completion handler must be: |
433 | * | |
434 | * @code void handler(std::exception_ptr); @endcode | |
435 | * Otherwise, the function signature of the completion handler must be: | |
436 | * @code void handler(std::exception_ptr, R); @endcode | |
437 | * | |
1e59de90 TL |
438 | * @par Completion Signature |
439 | * @code void(std::exception_ptr, R) @endcode | |
440 | * where @c R is the first template argument to the @c awaitable returned by the | |
441 | * supplied function object @c F: | |
442 | * @code boost::asio::awaitable<R, AwaitableExecutor> F() @endcode | |
20effc67 TL |
443 | * |
444 | * @par Example | |
445 | * @code | |
446 | * boost::asio::awaitable<std::size_t> echo(tcp::socket socket) | |
447 | * { | |
448 | * std::size_t bytes_transferred = 0; | |
449 | * | |
450 | * try | |
451 | * { | |
452 | * char data[1024]; | |
453 | * for (;;) | |
454 | * { | |
455 | * std::size_t n = co_await socket.async_read_some( | |
456 | * boost::asio::buffer(data), boost::asio::use_awaitable); | |
457 | * | |
458 | * co_await boost::asio::async_write(socket, | |
459 | * boost::asio::buffer(data, n), boost::asio::use_awaitable); | |
460 | * | |
461 | * bytes_transferred += n; | |
462 | * } | |
463 | * } | |
464 | * catch (const std::exception&) | |
465 | * { | |
466 | * } | |
467 | * | |
468 | * co_return bytes_transferred; | |
469 | * } | |
470 | * | |
471 | * // ... | |
92f5a8d4 | 472 | * |
20effc67 TL |
473 | * boost::asio::co_spawn(my_io_context, |
474 | * [socket = std::move(my_tcp_socket)]() mutable | |
475 | * -> boost::asio::awaitable<void> | |
476 | * { | |
477 | * try | |
478 | * { | |
479 | * char data[1024]; | |
480 | * for (;;) | |
481 | * { | |
482 | * std::size_t n = co_await socket.async_read_some( | |
483 | * boost::asio::buffer(data), boost::asio::use_awaitable); | |
92f5a8d4 | 484 | * |
20effc67 TL |
485 | * co_await boost::asio::async_write(socket, |
486 | * boost::asio::buffer(data, n), boost::asio::use_awaitable); | |
487 | * } | |
488 | * } | |
489 | * catch (const std::exception& e) | |
490 | * { | |
491 | * std::cerr << "Exception: " << e.what() << "\n"; | |
492 | * } | |
493 | * }, boost::asio::detached); | |
494 | * @endcode | |
1e59de90 TL |
495 | * |
496 | * @par Per-Operation Cancellation | |
497 | * The new thread of execution is created with a cancellation state that | |
498 | * supports @c cancellation_type::terminal values only. To change the | |
499 | * cancellation state, call boost::asio::this_coro::reset_cancellation_state. | |
92f5a8d4 TL |
500 | */ |
501 | template <typename ExecutionContext, typename F, | |
502 | BOOST_ASIO_COMPLETION_TOKEN_FOR(typename detail::awaitable_signature< | |
503 | typename result_of<F()>::type>::type) CompletionToken | |
504 | BOOST_ASIO_DEFAULT_COMPLETION_TOKEN_TYPE( | |
505 | typename ExecutionContext::executor_type)> | |
506 | BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, | |
507 | typename detail::awaitable_signature<typename result_of<F()>::type>::type) | |
508 | co_spawn(ExecutionContext& ctx, F&& f, | |
509 | CompletionToken&& token | |
510 | BOOST_ASIO_DEFAULT_COMPLETION_TOKEN( | |
511 | typename ExecutionContext::executor_type), | |
1e59de90 | 512 | typename constraint< |
92f5a8d4 | 513 | is_convertible<ExecutionContext&, execution_context&>::value |
1e59de90 | 514 | >::type = 0); |
92f5a8d4 TL |
515 | |
516 | } // namespace asio | |
517 | } // namespace boost | |
518 | ||
519 | #include <boost/asio/detail/pop_options.hpp> | |
520 | ||
521 | #include <boost/asio/impl/co_spawn.hpp> | |
522 | ||
523 | #endif // defined(BOOST_ASIO_HAS_CO_AWAIT) || defined(GENERATING_DOCUMENTATION) | |
524 | ||
525 | #endif // BOOST_ASIO_CO_SPAWN_HPP |