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# Copyright (C) 2001 Python Software Foundation
# This file is distributed under the same license as the Python package.
#
# Translators:
# Adrian Liaw <[email protected]>, 2018
# Matt Wang <mattwang44gmail.com>, 2022
msgid ""
msgstr ""
"Project-Id-Version: Python 3.14\n"
"Report-Msgid-Bugs-To: \n"
"POT-Creation-Date: 2026-03-22 00:20+0000\n"
"PO-Revision-Date: 2023-02-18 14:17+0800\n"
"Last-Translator: Matt Wang <mattwang44gmail.com>\n"
"Language-Team: Chinese - TAIWAN (https://github.com/python/python-docs-zh-"
"tw)\n"
"Language: zh_TW\n"
"MIME-Version: 1.0\n"
"Content-Type: text/plain; charset=UTF-8\n"
"Content-Transfer-Encoding: 8bit\n"
"Plural-Forms: nplurals=1; plural=0;\n"
"X-Generator: Poedit 3.2.2\n"
#: ../../library/asyncio-dev.rst:7
msgid "Developing with asyncio"
msgstr "使用 asyncio 開發"
#: ../../library/asyncio-dev.rst:9
msgid ""
"Asynchronous programming is different from classic \"sequential\" "
"programming."
msgstr ""
"非同步程式設計 (asynchronous programming) 與傳統的\"順序\"程式設計 "
"(sequential programming) 不同。"
#: ../../library/asyncio-dev.rst:12
msgid ""
"This page lists common mistakes and traps and explains how to avoid them."
msgstr "本頁列出常見的錯誤和陷阱,並解釋如何避免它們。"
#: ../../library/asyncio-dev.rst:19
msgid "Debug Mode"
msgstr "除錯模式"
#: ../../library/asyncio-dev.rst:21
msgid ""
"By default asyncio runs in production mode. In order to ease the "
"development asyncio has a *debug mode*."
msgstr ""
"在預設情況下 asyncio 以正式生產模式 (production mode) 執行。為了讓開發更輕"
"鬆,asyncio 還有一種\\ *除錯模式 (debug mode)*。"
#: ../../library/asyncio-dev.rst:24
msgid "There are several ways to enable asyncio debug mode:"
msgstr "有幾種方法可以啟用 asyncio 除錯模式:"
#: ../../library/asyncio-dev.rst:26
msgid "Setting the :envvar:`PYTHONASYNCIODEBUG` environment variable to ``1``."
msgstr "將 :envvar:`PYTHONASYNCIODEBUG` 環境變數設定為 ``1``。"
#: ../../library/asyncio-dev.rst:28
msgid "Using the :ref:`Python Development Mode <devmode>`."
msgstr "使用 :ref:`Python 開發模式 (Development Mode) <devmode>`。"
#: ../../library/asyncio-dev.rst:30
msgid "Passing ``debug=True`` to :func:`asyncio.run`."
msgstr "將 ``debug=True`` 傳遞給 :func:`asyncio.run`。"
#: ../../library/asyncio-dev.rst:32
msgid "Calling :meth:`loop.set_debug`."
msgstr "呼叫 :meth:`loop.set_debug`。"
#: ../../library/asyncio-dev.rst:34
msgid "In addition to enabling the debug mode, consider also:"
msgstr "除了啟用除錯模式外,還要考慮:"
#: ../../library/asyncio-dev.rst:36
msgid ""
"setting the log level of the :ref:`asyncio logger <asyncio-logger>` to :py:"
"const:`logging.DEBUG`, for example the following snippet of code can be run "
"at startup of the application::"
msgstr ""
"將 :ref:`asyncio logger(日誌記錄器) <asyncio-logger>`\\ 的日誌級别設置為 :"
"py:const:`logging.DEBUG`,例如下面的程式片段可以在應用程式啟動時運行: ::"
#: ../../library/asyncio-dev.rst:40
msgid "logging.basicConfig(level=logging.DEBUG)"
msgstr "logging.basicConfig(level=logging.DEBUG)"
#: ../../library/asyncio-dev.rst:42
msgid ""
"configuring the :mod:`warnings` module to display :exc:`ResourceWarning` "
"warnings. One way of doing that is by using the :option:`-W` ``default`` "
"command line option."
msgstr ""
"配置 :mod:`warnings` 模組以顯示 :exc:`ResourceWarning` 警告。一種方法是使用 :"
"option:`-W` ``default`` 命令列選項。"
#: ../../library/asyncio-dev.rst:47
msgid "When the debug mode is enabled:"
msgstr "啟用除錯模式時:"
#: ../../library/asyncio-dev.rst:49
msgid ""
"Many non-threadsafe asyncio APIs (such as :meth:`loop.call_soon` and :meth:"
"`loop.call_at` methods) raise an exception if they are called from a wrong "
"thread."
msgstr ""
"許多非執行緒安全 (non-threadsafe) 的 asyncio APIs(例如 :meth:`loop."
"call_soon` 和 :meth:`loop.call_at` 方法),如果從錯誤的執行緒呼叫就會引發例"
"外。"
#: ../../library/asyncio-dev.rst:53
msgid ""
"The execution time of the I/O selector is logged if it takes too long to "
"perform an I/O operation."
msgstr ""
"如果執行一個 I/O 操作花費的時間太長,則將 I/O 選擇器 (selector) 的執行時間記"
"錄到日誌中。"
#: ../../library/asyncio-dev.rst:56
msgid ""
"Callbacks taking longer than 100 milliseconds are logged. The :attr:`loop."
"slow_callback_duration` attribute can be used to set the minimum execution "
"duration in seconds that is considered \"slow\"."
msgstr ""
"執行時間超過 100 毫秒的回呼 (callback) 將會被記錄於日誌。屬性 :attr:`loop."
"slow_callback_duration` 可用於設定以秒為單位的最小執行持續時間,超過這個值執"
"行時間就會被視為\"緩慢\"。"
#: ../../library/asyncio-dev.rst:64
msgid "Concurrency and Multithreading"
msgstr "並行性和多執行緒 (Concurrency and Multithreading)"
#: ../../library/asyncio-dev.rst:66
msgid ""
"An event loop runs in a thread (typically the main thread) and executes all "
"callbacks and Tasks in its thread. While a Task is running in the event "
"loop, no other Tasks can run in the same thread. When a Task executes an "
"``await`` expression, the running Task gets suspended, and the event loop "
"executes the next Task."
msgstr ""
"事件迴圈在執行緒中運行(通常是主執行緒),並在其執行緒中執行所有回呼和 Tasks"
"(任務)。當一個 Task 在事件迴圈中運行時,沒有其他 Task 可以在同一個執行緒中"
"運行。當一個 Task 執行一個 ``await`` 運算式時,正在執行的 Task 會被暫停,而事"
"件迴圈會執行下一個 Task。"
#: ../../library/asyncio-dev.rst:72
msgid ""
"To schedule a :term:`callback` from another OS thread, the :meth:`loop."
"call_soon_threadsafe` method should be used. Example::"
msgstr ""
"要從不同的 OS 執行緒為一個 :term:`callback` 排程,應該使用 :meth:`loop."
"call_soon_threadsafe` 方法。例如: ::"
#: ../../library/asyncio-dev.rst:75
msgid "loop.call_soon_threadsafe(callback, *args)"
msgstr "loop.call_soon_threadsafe(callback, *args)"
#: ../../library/asyncio-dev.rst:77
msgid ""
"Almost all asyncio objects are not thread safe, which is typically not a "
"problem unless there is code that works with them from outside of a Task or "
"a callback. If there's a need for such code to call a low-level asyncio "
"API, the :meth:`loop.call_soon_threadsafe` method should be used, e.g.::"
msgstr ""
"幾乎所有 asyncio 物件都不支援執行緒安全 (thread safe),這通常不是問題,除非"
"在 Task 或回呼函式之外有程式需要和它們一起運作。如果需要這樣的程式來呼叫低階 "
"asyncio API,應該使用 :meth:`loop.call_soon_threadsafe` 方法,例如: ::"
#: ../../library/asyncio-dev.rst:83
msgid "loop.call_soon_threadsafe(fut.cancel)"
msgstr "loop.call_soon_threadsafe(fut.cancel)"
#: ../../library/asyncio-dev.rst:85
msgid ""
"To schedule a coroutine object from a different OS thread, the :func:"
"`run_coroutine_threadsafe` function should be used. It returns a :class:"
"`concurrent.futures.Future` to access the result::"
msgstr ""
"要從不同的 OS 執行緒為一個協程物件排程,應該使用 :func:"
"`run_coroutine_threadsafe` 函式。它會回傳一個 :class:`concurrent.futures."
"Future` 以存取結果: ::"
#: ../../library/asyncio-dev.rst:89
msgid ""
"async def coro_func():\n"
" return await asyncio.sleep(1, 42)\n"
"\n"
"# Later in another OS thread:\n"
"\n"
"future = asyncio.run_coroutine_threadsafe(coro_func(), loop)\n"
"# Wait for the result:\n"
"result = future.result()"
msgstr ""
"async def coro_func():\n"
" return await asyncio.sleep(1, 42)\n"
"\n"
"# 之後在另一個 OS 執行緒中:\n"
"\n"
"future = asyncio.run_coroutine_threadsafe(coro_func(), loop)\n"
"# 等待結果:\n"
"result = future.result()"
#: ../../library/asyncio-dev.rst:98
msgid "To handle signals the event loop must be run in the main thread."
msgstr "為了能夠處理訊號,事件迴圈必須於主執行緒中運行。"
#: ../../library/asyncio-dev.rst:101
msgid ""
"The :meth:`loop.run_in_executor` method can be used with a :class:"
"`concurrent.futures.ThreadPoolExecutor` or :class:`~concurrent.futures."
"InterpreterPoolExecutor` to execute blocking code in a different OS thread "
"without blocking the OS thread that the event loop runs in."
msgstr ""
":meth:`loop.run_in_executor` 方法可以和 :class:`concurrent.futures."
"ThreadPoolExecutor` 或 :class:`~concurrent.futures.InterpreterPoolExecutor` "
"一起使用,這能夠在作業系統上另一個不同的執行緒中執行阻塞程式,且避免阻塞執行"
"事件迴圈的執行緒。"
#: ../../library/asyncio-dev.rst:107
msgid ""
"There is currently no way to schedule coroutines or callbacks directly from "
"a different process (such as one started with :mod:`multiprocessing`). The :"
"ref:`asyncio-event-loop-methods` section lists APIs that can read from pipes "
"and watch file descriptors without blocking the event loop. In addition, "
"asyncio's :ref:`Subprocess <asyncio-subprocess>` APIs provide a way to start "
"a process and communicate with it from the event loop. Lastly, the "
"aforementioned :meth:`loop.run_in_executor` method can also be used with a :"
"class:`concurrent.futures.ProcessPoolExecutor` to execute code in a "
"different process."
msgstr ""
"目前沒有什麼辦法能直接從另一個行程(例如透過 :mod:`multiprocessing` 啟動的程"
"序)來為協程或回呼排程。:ref:`asyncio-event-loop-methods`\\ 小節列出了可以從 "
"pipes(管道)讀取並監視 file descriptor(檔案描述器)而不會阻塞事件迴圈的 "
"API。此外,asyncio 的\\ :ref:`子行程 <asyncio-subprocess>` API 提供了一種啟動"
"行程並從事件迴圈與其通訊的辦法。最後,之前提到的 :meth:`loop."
"run_in_executor` 方法也可和 :class:`concurrent.futures.ProcessPoolExecutor` "
"搭配使用,以在另一個行程中執行程式。"
#: ../../library/asyncio-dev.rst:121
msgid "Running Blocking Code"
msgstr "執行阻塞的程式"
#: ../../library/asyncio-dev.rst:123
msgid ""
"Blocking (CPU-bound) code should not be called directly. For example, if a "
"function performs a CPU-intensive calculation for 1 second, all concurrent "
"asyncio Tasks and IO operations would be delayed by 1 second."
msgstr ""
"不應該直接呼叫阻塞(CPU 密集型)程式。例如一個執行 1 秒 CPU 密集型計算的函"
"式,那麼所有並行非同步 Tasks 和 IO 操作都會被延遲 1 秒。"
#: ../../library/asyncio-dev.rst:128
msgid ""
"An executor can be used to run a task in a different thread, including in a "
"different interpreter, or even in a different process to avoid blocking the "
"OS thread with the event loop. See the :meth:`loop.run_in_executor` method "
"for more details."
msgstr ""
"一個 executor(執行器)可以被用來在不同的執行緒(包含不同直譯器)、或甚至不同"
"的行程中執行任務,以避免事件迴圈阻塞了 OS 執行緒。詳情請見 :meth:`loop."
"run_in_executor` 方法。"
#: ../../library/asyncio-dev.rst:138
msgid "Logging"
msgstr "日誌記錄"
#: ../../library/asyncio-dev.rst:140
msgid ""
"asyncio uses the :mod:`logging` module and all logging is performed via the "
"``\"asyncio\"`` logger."
msgstr ""
"asyncio 使用 :mod:`logging` 模組,所有日誌記錄都是透過 ``\"asyncio\"`` "
"logger 執行的。"
#: ../../library/asyncio-dev.rst:143
msgid ""
"The default log level is :py:const:`logging.INFO`, which can be easily "
"adjusted::"
msgstr "日誌級別被預設為 :py:const:`logging.INFO`,它可以很容易地被調整: ::"
#: ../../library/asyncio-dev.rst:146
msgid "logging.getLogger(\"asyncio\").setLevel(logging.WARNING)"
msgstr "logging.getLogger(\"asyncio\").setLevel(logging.WARNING)"
#: ../../library/asyncio-dev.rst:149
msgid ""
"Network logging can block the event loop. It is recommended to use a "
"separate thread for handling logs or use non-blocking IO. For example, see :"
"ref:`blocking-handlers`."
msgstr ""
"網路日誌記錄可能會阻塞事件迴圈。建議使用獨立的執行緒來處理日誌或使用非阻塞 "
"IO,範例請參見 :ref:`blocking-handlers`。"
#: ../../library/asyncio-dev.rst:157
msgid "Detect never-awaited coroutines"
msgstr "偵測從未被等待的 (never-awaited) 協程"
#: ../../library/asyncio-dev.rst:159
msgid ""
"When a coroutine function is called, but not awaited (e.g. ``coro()`` "
"instead of ``await coro()``) or the coroutine is not scheduled with :meth:"
"`asyncio.create_task`, asyncio will emit a :exc:`RuntimeWarning`::"
msgstr ""
"當協程函式被呼叫而不是被等待時(即執行 ``coro()`` 而不是 ``await coro()``)或"
"者協程沒有透過 :meth:`asyncio.create_task` 被排程,asyncio 將會發出 :exc:"
"`RuntimeWarning`: ::"
#: ../../library/asyncio-dev.rst:164
msgid ""
"import asyncio\n"
"\n"
"async def test():\n"
" print(\"never scheduled\")\n"
"\n"
"async def main():\n"
" test()\n"
"\n"
"asyncio.run(main())"
msgstr ""
"import asyncio\n"
"\n"
"async def test():\n"
" print(\"never scheduled\")\n"
"\n"
"async def main():\n"
" test()\n"
"\n"
"asyncio.run(main())"
#: ../../library/asyncio-dev.rst:174 ../../library/asyncio-dev.rst:219
#: ../../library/asyncio-dev.rst:393 ../../library/asyncio-dev.rst:450
msgid "Output::"
msgstr "輸出: ::"
#: ../../library/asyncio-dev.rst:176
msgid ""
"test.py:7: RuntimeWarning: coroutine 'test' was never awaited\n"
" test()"
msgstr ""
"test.py:7: RuntimeWarning: coroutine 'test' was never awaited\n"
" test()"
#: ../../library/asyncio-dev.rst:179 ../../library/asyncio-dev.rst:235
msgid "Output in debug mode::"
msgstr "除錯模式中的輸出: ::"
#: ../../library/asyncio-dev.rst:181
msgid ""
"test.py:7: RuntimeWarning: coroutine 'test' was never awaited\n"
"Coroutine created at (most recent call last)\n"
" File \"../t.py\", line 9, in <module>\n"
" asyncio.run(main(), debug=True)\n"
"\n"
" < .. >\n"
"\n"
" File \"../t.py\", line 7, in main\n"
" test()\n"
" test()"
msgstr ""
"test.py:7: RuntimeWarning: coroutine 'test' was never awaited\n"
"Coroutine created at (most recent call last)\n"
" File \"../t.py\", line 9, in <module>\n"
" asyncio.run(main(), debug=True)\n"
"\n"
" < .. >\n"
"\n"
" File \"../t.py\", line 7, in main\n"
" test()\n"
" test()"
#: ../../library/asyncio-dev.rst:192
msgid ""
"The usual fix is to either await the coroutine or call the :meth:`asyncio."
"create_task` function::"
msgstr ""
"常用的修復方法是去等待協程或者呼叫 :meth:`asyncio.create_task` 函式: ::"
#: ../../library/asyncio-dev.rst:195
msgid ""
"async def main():\n"
" await test()"
msgstr ""
"async def main():\n"
" await test()"
#: ../../library/asyncio-dev.rst:200
msgid "Detect never-retrieved exceptions"
msgstr "偵測從未被取得的 (never-retrieved) 例外"
#: ../../library/asyncio-dev.rst:202
msgid ""
"If a :meth:`Future.set_exception` is called but the Future object is never "
"awaited on, the exception would never be propagated to the user code. In "
"this case, asyncio would emit a log message when the Future object is "
"garbage collected."
msgstr ""
"如果呼叫 :meth:`Future.set_exception`,但 Future 物件從未被等待,例外將無法被"
"傳播 (propagate) 到使用者程式。在這種情況下,當 Future 物件被垃圾回收 "
"(garbage collected) 時,asyncio 將發出一則日誌訊息。"
#: ../../library/asyncio-dev.rst:207
msgid "Example of an unhandled exception::"
msgstr "未處理例外的例子: ::"
#: ../../library/asyncio-dev.rst:209
msgid ""
"import asyncio\n"
"\n"
"async def bug():\n"
" raise Exception(\"not consumed\")\n"
"\n"
"async def main():\n"
" asyncio.create_task(bug())\n"
"\n"
"asyncio.run(main())"
msgstr ""
"import asyncio\n"
"\n"
"async def bug():\n"
" raise Exception(\"not consumed\")\n"
"\n"
"async def main():\n"
" asyncio.create_task(bug())\n"
"\n"
"asyncio.run(main())"
#: ../../library/asyncio-dev.rst:221
msgid ""
"Task exception was never retrieved\n"
"future: <Task finished coro=<bug() done, defined at test.py:3>\n"
" exception=Exception('not consumed')>\n"
"\n"
"Traceback (most recent call last):\n"
" File \"test.py\", line 4, in bug\n"
" raise Exception(\"not consumed\")\n"
"Exception: not consumed"
msgstr ""
"Task exception was never retrieved\n"
"future: <Task finished coro=<bug() done, defined at test.py:3>\n"
" exception=Exception('not consumed')>\n"
"\n"
"Traceback (most recent call last):\n"
" File \"test.py\", line 4, in bug\n"
" raise Exception(\"not consumed\")\n"
"Exception: not consumed"
#: ../../library/asyncio-dev.rst:230
msgid ""
":ref:`Enable the debug mode <asyncio-debug-mode>` to get the traceback where "
"the task was created::"
msgstr ""
":ref:`啟用除錯模式 <asyncio-debug-mode>`\\ 以取得任務建立處的追蹤資訊 "
"(traceback): ::"
#: ../../library/asyncio-dev.rst:233
msgid "asyncio.run(main(), debug=True)"
msgstr "asyncio.run(main(), debug=True)"
#: ../../library/asyncio-dev.rst:237
msgid ""
"Task exception was never retrieved\n"
"future: <Task finished coro=<bug() done, defined at test.py:3>\n"
" exception=Exception('not consumed') created at asyncio/tasks.py:321>\n"
"\n"
"source_traceback: Object created at (most recent call last):\n"
" File \"../t.py\", line 9, in <module>\n"
" asyncio.run(main(), debug=True)\n"
"\n"
"< .. >\n"
"\n"
"Traceback (most recent call last):\n"
" File \"../t.py\", line 4, in bug\n"
" raise Exception(\"not consumed\")\n"
"Exception: not consumed"
msgstr ""
"Task exception was never retrieved\n"
"future: <Task finished coro=<bug() done, defined at test.py:3>\n"
" exception=Exception('not consumed') created at asyncio/tasks.py:321>\n"
"\n"
"source_traceback: Object created at (most recent call last):\n"
" File \"../t.py\", line 9, in <module>\n"
" asyncio.run(main(), debug=True)\n"
"\n"
"< .. >\n"
"\n"
"Traceback (most recent call last):\n"
" File \"../t.py\", line 4, in bug\n"
" raise Exception(\"not consumed\")\n"
"Exception: not consumed"
#: ../../library/asyncio-dev.rst:254
msgid "Asynchronous generators best practices"
msgstr ""
#: ../../library/asyncio-dev.rst:256
msgid ""
"Writing correct and efficient asyncio code requires awareness of certain "
"pitfalls. This section outlines essential best practices that can save you "
"hours of debugging."
msgstr ""
#: ../../library/asyncio-dev.rst:261
msgid "Close asynchronous generators explicitly"
msgstr ""
#: ../../library/asyncio-dev.rst:263
msgid ""
"It is recommended to manually close the :term:`asynchronous generator "
"<asynchronous generator iterator>`. If a generator exits early - for "
"example, due to an exception raised in the body of an ``async for`` loop - "
"its asynchronous cleanup code may run in an unexpected context. This can "
"occur after the tasks it depends on have completed, or during the event loop "
"shutdown when the async-generator's garbage collection hook is called."
msgstr ""
#: ../../library/asyncio-dev.rst:271
msgid ""
"To avoid this, explicitly close the generator by calling its :meth:`~agen."
"aclose` method, or use the :func:`contextlib.aclosing` context manager::"
msgstr ""
#: ../../library/asyncio-dev.rst:275
msgid ""
"import asyncio\n"
"import contextlib\n"
"\n"
"async def gen():\n"
" yield 1\n"
" yield 2\n"
"\n"
"async def func():\n"
" async with contextlib.aclosing(gen()) as g:\n"
" async for x in g:\n"
" break # Don't iterate until the end\n"
"\n"
"asyncio.run(func())"
msgstr ""
#: ../../library/asyncio-dev.rst:289
msgid ""
"As noted above, the cleanup code for these asynchronous generators is "
"deferred. The following example demonstrates that the finalization of an "
"asynchronous generator can occur in an unexpected order::"
msgstr ""
#: ../../library/asyncio-dev.rst:293
msgid ""
"import asyncio\n"
"work_done = False\n"
"\n"
"async def cursor():\n"
" try:\n"
" yield 1\n"
" finally:\n"
" assert work_done\n"
"\n"
"async def rows():\n"
" global work_done\n"
" try:\n"
" yield 2\n"
" finally:\n"
" await asyncio.sleep(0.1) # immitate some async work\n"
" work_done = True\n"
"\n"
"\n"
"async def main():\n"
" async for c in cursor():\n"
" async for r in rows():\n"
" break\n"
" break\n"
"\n"
"asyncio.run(main())"
msgstr ""
#: ../../library/asyncio-dev.rst:319
msgid "For this example, we get the following output::"
msgstr ""
#: ../../library/asyncio-dev.rst:321
msgid ""
"unhandled exception during asyncio.run() shutdown\n"
"task: <Task finished name='Task-3' coro=<<async_generator_athrow without "
"__name__>()> exception=AssertionError()>\n"
"Traceback (most recent call last):\n"
" File \"example.py\", line 6, in cursor\n"
" yield 1\n"
"asyncio.exceptions.CancelledError\n"
"\n"
"During handling of the above exception, another exception occurred:\n"
"\n"
"Traceback (most recent call last):\n"
" File \"example.py\", line 8, in cursor\n"
" assert work_done\n"
" ^^^^^^^^^\n"
"AssertionError"
msgstr ""
#: ../../library/asyncio-dev.rst:336
msgid ""
"The ``cursor()`` asynchronous generator was finalized before the ``rows`` "
"generator - an unexpected behavior."
msgstr ""
#: ../../library/asyncio-dev.rst:339
msgid ""
"The example can be fixed by explicitly closing the ``cursor`` and ``rows`` "
"async-generators::"
msgstr ""
#: ../../library/asyncio-dev.rst:342
msgid ""
"async def main():\n"
" async with contextlib.aclosing(cursor()) as cursor_gen:\n"
" async for c in cursor_gen:\n"
" async with contextlib.aclosing(rows()) as rows_gen:\n"
" async for r in rows_gen:\n"
" break\n"
" break"
msgstr ""
#: ../../library/asyncio-dev.rst:352
msgid "Create asynchronous generators only when the event loop is running"
msgstr ""
#: ../../library/asyncio-dev.rst:354
msgid ""
"It is recommended to create :term:`asynchronous generators <asynchronous "
"generator iterator>` only after the event loop has been created."
msgstr ""
#: ../../library/asyncio-dev.rst:358
msgid ""
"To ensure that asynchronous generators close reliably, the event loop uses "
"the :func:`sys.set_asyncgen_hooks` function to register callback functions. "
"These callbacks update the list of running asynchronous generators to keep "
"it in a consistent state."
msgstr ""
#: ../../library/asyncio-dev.rst:363
msgid ""
"When the :meth:`loop.shutdown_asyncgens() <asyncio.loop.shutdown_asyncgens>` "
"function is called, the running generators are stopped gracefully and the "
"list is cleared."
msgstr ""
#: ../../library/asyncio-dev.rst:367
msgid ""
"The asynchronous generator invokes the corresponding system hook during its "
"first iteration. At the same time, the generator records that the hook has "
"been called and does not call it again."
msgstr ""
#: ../../library/asyncio-dev.rst:371
msgid ""
"Therefore, if iteration begins before the event loop is created, the event "
"loop will not be able to add the generator to its list of active generators "
"because the hooks are set after the generator attempts to call them. "
"Consequently, the event loop will not be able to terminate the generator if "
"necessary."
msgstr ""
#: ../../library/asyncio-dev.rst:377
msgid "Consider the following example::"
msgstr ""
#: ../../library/asyncio-dev.rst:379
msgid ""
"import asyncio\n"
"\n"
"async def agenfn():\n"
" try:\n"
" yield 10\n"
" finally:\n"
" await asyncio.sleep(0)\n"
"\n"
"\n"
"with asyncio.Runner() as runner:\n"
" agen = agenfn()\n"
" print(runner.run(anext(agen)))\n"
" del agen"
msgstr ""
#: ../../library/asyncio-dev.rst:395
msgid ""
"10\n"
"Exception ignored while closing generator <async_generator object agenfn at "
"0x000002F71CD10D70>:\n"
"Traceback (most recent call last):\n"
" File \"example.py\", line 13, in <module>\n"
" del agen\n"
" ^^^^\n"
"RuntimeError: async generator ignored GeneratorExit"
msgstr ""
#: ../../library/asyncio-dev.rst:403
msgid "This example can be fixed as follows::"
msgstr ""
#: ../../library/asyncio-dev.rst:405
msgid ""
"import asyncio\n"
"\n"
"async def agenfn():\n"
" try:\n"
" yield 10\n"
" finally:\n"
" await asyncio.sleep(0)\n"
"\n"
"async def main():\n"
" agen = agenfn()\n"
" print(await anext(agen))\n"
" del agen\n"
"\n"
"asyncio.run(main())"
msgstr ""
"import asyncio\n"
"\n"
"async def agenfn():\n"
" try:\n"
" yield 10\n"
" finally:\n"
" await asyncio.sleep(0)\n"
"\n"
"async def main():\n"
" agen = agenfn()\n"
" print(await anext(agen))\n"
" del agen\n"
"\n"
"asyncio.run(main())"
#: ../../library/asyncio-dev.rst:422
msgid "Avoid concurrent iteration and closure of the same generator"
msgstr ""
#: ../../library/asyncio-dev.rst:424
msgid ""
"Async generators may be reentered while another :meth:`~agen.__anext__` / :"
"meth:`~agen.athrow` / :meth:`~agen.aclose` call is in progress. This may "
"lead to an inconsistent state of the async generator and can cause errors."
msgstr ""
#: ../../library/asyncio-dev.rst:429
msgid "Let's consider the following example::"
msgstr ""
#: ../../library/asyncio-dev.rst:431
msgid ""
"import asyncio\n"
"\n"
"async def consumer():\n"
" for idx in range(100):\n"
" await asyncio.sleep(0)\n"
" message = yield idx\n"
" print('received', message)\n"
"\n"
"async def amain():\n"
" agenerator = consumer()\n"
" await agenerator.asend(None)\n"
"\n"
" fa = asyncio.create_task(agenerator.asend('A'))\n"
" fb = asyncio.create_task(agenerator.asend('B'))\n"
" await fa\n"
" await fb\n"
"\n"
"asyncio.run(amain())"
msgstr ""
#: ../../library/asyncio-dev.rst:452
msgid ""
"received A\n"
"Traceback (most recent call last):\n"
" File \"test.py\", line 38, in <module>\n"
" asyncio.run(amain())\n"
" ~~~~~~~~~~~^^^^^^^^^\n"
" File \"Lib/asyncio/runners.py\", line 204, in run\n"
" return runner.run(main)\n"
" ~~~~~~~~~~^^^^^^\n"
" File \"Lib/asyncio/runners.py\", line 127, in run\n"
" return self._loop.run_until_complete(task)\n"
" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^\n"
" File \"Lib/asyncio/base_events.py\", line 719, in run_until_complete\n"
" return future.result()\n"
" ~~~~~~~~~~~~~^^\n"
" File \"test.py\", line 36, in amain\n"
" await fb\n"
"RuntimeError: anext(): asynchronous generator is already running"
msgstr ""
#: ../../library/asyncio-dev.rst:471
msgid ""
"Therefore, it is recommended to avoid using asynchronous generators in "
"parallel tasks or across multiple event loops."
msgstr ""