##// END OF EJS Templates
Minor: typos, grammar
Frank Tobia -
r25836:5b71b724
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@@ -8,7 +8,7 Asynchronous in REPL: Autoawait
8 This feature is experimental and behavior can change between python and
8 This feature is experimental and behavior can change between python and
9 IPython version without prior deprecation.
9 IPython version without prior deprecation.
10
10
11 Starting with IPython 7.0, and when user Python 3.6 and above, IPython offer the
11 Starting with IPython 7.0, and when using Python 3.6 and above, IPython offer the
12 ability to run asynchronous code from the REPL. Constructs which are
12 ability to run asynchronous code from the REPL. Constructs which are
13 :exc:`SyntaxError` s in the Python REPL can be used seamlessly in IPython.
13 :exc:`SyntaxError` s in the Python REPL can be used seamlessly in IPython.
14
14
@@ -19,7 +19,7 will differ between IPython, IPykernel and their versions.
19
19
20 When a supported library is used, IPython will automatically allow Futures and
20 When a supported library is used, IPython will automatically allow Futures and
21 Coroutines in the REPL to be ``await`` ed. This will happen if an :ref:`await
21 Coroutines in the REPL to be ``await`` ed. This will happen if an :ref:`await
22 <await>` (or any other async constructs like async-with, async-for) is use at
22 <await>` (or any other async constructs like async-with, async-for) is used at
23 top level scope, or if any structure valid only in `async def
23 top level scope, or if any structure valid only in `async def
24 <https://docs.python.org/3/reference/compound_stmts.html#async-def>`_ function
24 <https://docs.python.org/3/reference/compound_stmts.html#async-def>`_ function
25 context are present. For example, the following being a syntax error in the
25 context are present. For example, the following being a syntax error in the
@@ -73,7 +73,7 By default IPython will assume integration with Python's provided
73 :mod:`asyncio`, but integration with other libraries is provided. In particular
73 :mod:`asyncio`, but integration with other libraries is provided. In particular
74 we provide experimental integration with the ``curio`` and ``trio`` library.
74 we provide experimental integration with the ``curio`` and ``trio`` library.
75
75
76 You can switch current integration by using the
76 You can switch the current integration by using the
77 ``c.InteractiveShell.loop_runner`` option or the ``autoawait <name
77 ``c.InteractiveShell.loop_runner`` option or the ``autoawait <name
78 integration>`` magic.
78 integration>`` magic.
79
79
@@ -118,7 +118,7 to your code.
118
118
119 When using command line IPython, the default loop (or runner) does not process
119 When using command line IPython, the default loop (or runner) does not process
120 in the background, so top level asynchronous code must finish for the REPL to
120 in the background, so top level asynchronous code must finish for the REPL to
121 allow you to enter more code. As with usual Python semantic, the awaitables are
121 allow you to enter more code. As with usual Python semantics, the awaitables are
122 started only when awaited for the first time. That is to say, in first example,
122 started only when awaited for the first time. That is to say, in first example,
123 no network request is done between ``In[1]`` and ``In[2]``.
123 no network request is done between ``In[1]`` and ``In[2]``.
124
124
@@ -131,8 +131,8 a loop to run. By default IPython will use a fake coroutine runner which should
131 allow ``IPython.embed()`` to be nested. Though this will prevent usage of the
131 allow ``IPython.embed()`` to be nested. Though this will prevent usage of the
132 :magic:`%autoawait` feature when using IPython embed.
132 :magic:`%autoawait` feature when using IPython embed.
133
133
134 You can set explicitly a coroutine runner for ``embed()`` if you desire to run
134 You can set a coroutine runner explicitly for ``embed()`` if you want to run
135 asynchronous code, the exact behavior is though undefined.
135 asynchronous code, though the exact behavior is undefined.
136
136
137 Effects on Magics
137 Effects on Magics
138 -----------------
138 -----------------
@@ -140,14 +140,14 Effects on Magics
140 A couple of magics (``%%timeit``, ``%timeit``, ``%%time``, ``%%prun``) have not
140 A couple of magics (``%%timeit``, ``%timeit``, ``%%time``, ``%%prun``) have not
141 yet been updated to work with asynchronous code and will raise syntax errors
141 yet been updated to work with asynchronous code and will raise syntax errors
142 when trying to use top-level ``await``. We welcome any contribution to help fix
142 when trying to use top-level ``await``. We welcome any contribution to help fix
143 those, and extra cases we haven't caught yet. We hope for better support in Cor
143 those, and extra cases we haven't caught yet. We hope for better support in Core
144 Python for top-level Async code.
144 Python for top-level Async code.
145
145
146 Internals
146 Internals
147 ---------
147 ---------
148
148
149 As running asynchronous code is not supported in interactive REPL (as of Python
149 As running asynchronous code is not supported in interactive REPL (as of Python
150 3.7) we have to rely to a number of complex workaround and heuristic to allow
150 3.7) we have to rely to a number of complex workarounds and heuristics to allow
151 this to happen. It is interesting to understand how this works in order to
151 this to happen. It is interesting to understand how this works in order to
152 comprehend potential bugs, or provide a custom runner.
152 comprehend potential bugs, or provide a custom runner.
153
153
@@ -179,16 +179,16 significant overhead to this kind of code.
179 By default the generated coroutine function will be consumed by Asyncio's
179 By default the generated coroutine function will be consumed by Asyncio's
180 ``loop_runner = asyncio.get_evenloop().run_until_complete()`` method if
180 ``loop_runner = asyncio.get_evenloop().run_until_complete()`` method if
181 ``async`` mode is deemed necessary, otherwise the coroutine will just be
181 ``async`` mode is deemed necessary, otherwise the coroutine will just be
182 exhausted in a simple runner. It is though possible to change the default
182 exhausted in a simple runner. It is possible, though, to change the default
183 runner.
183 runner.
184
184
185 A loop runner is a *synchronous* function responsible from running a coroutine
185 A loop runner is a *synchronous* function responsible from running a coroutine
186 object.
186 object.
187
187
188 The runner is responsible from ensuring that ``coroutine`` run to completion,
188 The runner is responsible for ensuring that ``coroutine`` runs to completion,
189 and should return the result of executing the coroutine. Let's write a
189 and it should return the result of executing the coroutine. Let's write a
190 runner for ``trio`` that print a message when used as an exercise, ``trio`` is
190 runner for ``trio`` that print a message when used as an exercise, ``trio`` is
191 special as it usually prefer to run a function object and make a coroutine by
191 special as it usually prefers to run a function object and make a coroutine by
192 itself, we can get around this limitation by wrapping it in an async-def without
192 itself, we can get around this limitation by wrapping it in an async-def without
193 parameters and passing this value to ``trio``::
193 parameters and passing this value to ``trio``::
194
194
@@ -246,8 +246,8 Difference between terminal IPython and IPykernel
246 The exact asynchronous code running behavior varies between Terminal IPython and
246 The exact asynchronous code running behavior varies between Terminal IPython and
247 IPykernel. The root cause of this behavior is due to IPykernel having a
247 IPykernel. The root cause of this behavior is due to IPykernel having a
248 *persistent* `asyncio` loop running, while Terminal IPython starts and stops a
248 *persistent* `asyncio` loop running, while Terminal IPython starts and stops a
249 loop for each code block. This can lead to surprising behavior in some case if
249 loop for each code block. This can lead to surprising behavior in some cases if
250 you are used to manipulate asyncio loop yourself, see for example
250 you are used to manipulating asyncio loop yourself, see for example
251 :ghissue:`11303` for a longer discussion but here are some of the astonishing
251 :ghissue:`11303` for a longer discussion but here are some of the astonishing
252 cases.
252 cases.
253
253
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