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7.x Series

IPython 7.16

The default traceback mode will now skip frames that are marked with __tracebackhide__ = True and show how many traceback frames have been skipped. This can be toggled by using xmode with the --show or --hide attribute. It will have no effect on non verbose traceback modes.

The ipython debugger also now understands __tracebackhide__ as well and will skip hidden frames when displaying. Movement up and down the stack will skip the hidden frames and will show how many frames were hidden. Internal IPython frames are also now hidden by default. The behavior can be changed with the skip_hidden while in the debugger, command and accepts "yes", "no", "true" and "false" case insensitive parameters.

Misc Noticeable changes:

  • Exceptions are now (re)raised when running notebooks via the %run, helping to catch issues in workflows and pipelines. 12301
  • Fix inputhook for qt 5.15.0 12355
  • Fix wx inputhook 12375
  • Add handling for malformed pathext env var (Windows) 12367
  • use $SHELL in system_piped 12360 for uniform behavior with ipykernel.

Reproducible Build

IPython 7.15 reproducible build did not work, so we try again this month 12358.

API Changes

Change of API and exposed objects automatically detected using frappuccino (still in beta):

The following items are new and mostly related to understanding __tracebackbhide__:

+ IPython.core.debugger.Pdb.do_down(self, arg)
+ IPython.core.debugger.Pdb.do_skip_hidden(self, arg)
+ IPython.core.debugger.Pdb.do_up(self, arg)
+ IPython.core.debugger.Pdb.hidden_frames(self, stack)
+ IPython.core.debugger.Pdb.stop_here(self, frame)

The following items have been removed:

- IPython.core.debugger.Pdb.new_do_down
- IPython.core.debugger.Pdb.new_do_up

Those were implementation details.

IPython 7.15

IPython 7.15 brings a number of bug fixes and user facing improvements.

Misc Noticeable changes:

  • Long completion name have better elision in terminal 12284
  • I've started to test on Python 3.9 12307 and fix some errors.
  • Hi DPI scaling of figures when using qt eventloop 12314
  • Document the ability to have systemwide configuration for IPython. 12328
  • Fix issues with input autoformatting 12336
  • IPython.core.debugger.Pdb is now interruptible (12168, in 7.14 but forgotten in release notes)
  • Video HTML attributes (12212, in 7.14 but forgotten in release notes)

Reproducible Build

Starting with IPython 7.15, I am attempting to provide reproducible builds, that is to say you should be able from the source tree to generate an sdist and wheel that are identical byte for byte with the publish version on PyPI.

I've only tested on a couple of machines so far and the process is relatively straightforward, so this mean that IPython not only have a deterministic build process, but also I have either removed, or put under control all effects of the build environments on the final artifact. I encourage you to attempt the build process on your machine as documented in core_developer_guide and let me know if you do not obtain an identical artifact.

While reproducible builds is critical to check that the supply chain of (open source) software has not been compromised, it can also help to speedup many of the build processes in large environment (conda, apt...) by allowing better caching of intermediate build steps.

Learn more on https://reproducible-builds.org/. Reflections on trusting trust is also one of the cornerstone and recommended reads on this subject.

Note

The build commit from which the sdist is generated is also signed, so you should be able to check it has not been compromised, and the git repository is a merkle-tree, you can check the consistency with git-fsck which you likely want to enable by default.

NEP29: Last version to support Python 3.6

IPython 7.15 will be the Last IPython version to officially support Python 3.6, as stated by NumPy Enhancement Proposal 29. Starting with next minor version of IPython I may stop testing on Python 3.6 and may stop publishing release artifacts that install on Python 3.6

Highlighted features

Highlighted features are not new, but seem to not be widely known, this section will help you discover in more narrative form what you can do with IPython.

Increase Tab Completion Menu Height

In terminal IPython it is possible to increase the hight of the tab-completion menu. To do so set the value of TerminalInteractiveShell.space_for_menu, this will reserve more space at the bottom of the screen for various kind of menus in IPython including tab completion and searching in history.

Autoformat Code in the terminal

If you have a preferred code formatter, you can configure IPython to reformat your code. Set the value of TerminalInteractiveShell.autoformatter to for example 'black' and IPython will auto format your code when possible.

IPython 7.14

IPython 7.14 is a minor release that fix a couple of bugs and prepare compatibility with new or future versions of some libraries.

Important changes:

  • Fix compatibility with Sphinx 3+ 12235
  • Remove deprecated matplotlib parameter usage, compatibility with matplotlib 3.3+ :122250

Misc Changes

  • set .py extension when editing current buffer in vi/emacs. 12167
  • support for unicode identifiers in ?/?? 12208
  • add extra options to the Video Rich objects 12212
  • add pretty-printing to SimpleNamespace 12230

IPython.core.debugger.Pdb is now interruptible

A KeyboardInterrupt will now interrupt IPython's extended debugger, in order to make Jupyter able to interrupt it. (12168)

Video HTML attributes

Add an option to IPython.display.Video to change the attributes of the HTML display of the video (12212)

Pending deprecated imports

Many object present in IPython.core.display are there for internal use only, and should already been imported from IPython.display by users and external libraries. Trying to import those from IPython.core.display is still possible but will trigger a deprecation warning in later versions of IPython and will become errors in the future.

This will simplify compatibility with other Python kernels (like Xeus-Python), and simplify code base.

IPython 7.13

IPython 7.13 is the final release of the 7.x branch since master is diverging toward an 8.0. Exiting new features have already been merged in 8.0 and will not be available on the 7.x branch. All the changes below have been backported from the master branch.

  • Fix inability to run PDB when inside an event loop 12141
  • Fix ability to interrupt some processes on windows 12137
  • Fix debugger shortcuts 12132
  • improve tab completion when inside a string by removing irrelevant elements 12128
  • Fix display of filename tab completion when the path is long 12122
  • Many removal of Python 2 specific code path 12110
  • displaying wav files do not require NumPy anymore, and is 5x to 30x faster 12113

See the list of all closed issues and pull request on github.

IPython 7.12

IPython 7.12 is a minor update that mostly brings code cleanup, removal of longtime deprecated function and a couple update to documentation cleanup as well.

Notable changes are the following:

  • Exit non-zero when ipython is given a file path to run that doesn't exist 12074
  • Test PR on ARM64 with Travis-CI 12073
  • Update CI to work with latest Pytest 12086
  • Add infrastructure to run ipykernel eventloop via trio 12097
  • Support git blame ignore revs 12091
  • Start multi-line __repr__ s on their own line 12099

IPython 7.11.1

A couple of deprecated functions (no-op) have been reintroduces in py3compat as Cython was still relying on them, and will be removed in a couple of versions.

IPython 7.11

IPython 7.11 received a couple of compatibility fixes and code cleanup.

A number of function in the py3compat have been removed; a number of types in the IPython code base are now non-ambiguous and now always unicode instead of Union[Unicode,bytes]; many of the relevant code path have thus been simplified/cleaned and types annotation added.

IPython support several verbosity level from exceptions. xmode plain now support chained exceptions. 11999

We are starting to remove shell=True in some usages of subprocess. While not directly a security issue (as IPython is made to run arbitrary code anyway) it is not good practice and we'd like to show the example. 12023. This discussion was started by @mschwager thanks to a new auditing tool they are working on with duo-labs (dlint).

Work around some bugs in Python 3.9 tokenizer 12057

IPython will now print its version after a crash. 11986

This is likely the last release from the 7.x series that will see new feature. The master branch will soon accept large code changes and thrilling new features; the 7.x branch will only start to accept critical bug fixes, and update dependencies.

IPython 7.10.2

IPython 7.10.2 fix a couple of extra incompatibility between IPython, ipdb, asyncio and Prompt Toolkit 3.

IPython 7.10.1

IPython 7.10.1 fix a couple of incompatibilities with Prompt toolkit 3 (please update Prompt toolkit to 3.0.2 at least), and fixes some interaction with headless IPython.

IPython 7.10.0

IPython 7.10 is the first double digit minor release in the last decade, and first since the release of IPython 1.0, previous double digit minor release was in August 2009.

We've been trying to give you regular release on the last Friday of every month for a guaranty of rapid access to bug fixes and new features.

Unlike the previous first few releases that have seen only a couple of code changes, 7.10 bring a number of changes, new features and bugfixes.

Stop Support for Python 3.5 – Adopt NEP 29

IPython has decided to follow the informational NEP 29 which layout a clear policy as to which version of (C)Python and NumPy are supported.

We thus dropped support for Python 3.5, and cleaned up a number of code path that were Python-version dependant. If you are on 3.5 or earlier pip should automatically give you the latest compatible version of IPython so you do not need to pin to a given version.

Support for Prompt Toolkit 3.0

Prompt Toolkit 3.0 was release a week before IPython 7.10 and introduces a few breaking changes. We believe IPython 7.10 should be compatible with both Prompt Toolkit 2.x and 3.x, though it has not been extensively tested with 3.x so please report any issues.

Prompt Rendering Performance improvements

Pull Request 11933 introduced an optimisation in the prompt rendering logic that should decrease the resource usage of IPython when using the _default configuration but could potentially introduce a regression of functionalities if you are using a custom prompt.

We know assume if you haven't changed the default keybindings that the prompt will not change during the duration of your input – which is for example not true when using vi insert mode that switches between [ins] and [nor] for the current mode.

If you are experiencing any issue let us know.

Code autoformatting

The IPython terminal can now auto format your code just before entering a new line or executing a command. To do so use the --TerminalInteractiveShell.autoformatter option and set it to 'black'; if black is installed IPython will use black to format your code when possible.

IPython cannot always properly format your code; in particular it will auto formatting with black will only work if:

  • Your code does not contains magics or special python syntax.
  • There is no code after your cursor.

The Black API is also still in motion; so this may not work with all versions of black.

It should be possible to register custom formatter, though the API is till in flux.

Arbitrary Mimetypes Handing in Terminal (Aka inline images in terminal)

When using IPython terminal it is now possible to register function to handle arbitrary mimetypes. While rendering non-text based representation was possible in many jupyter frontend; it was not possible in terminal IPython, as usually terminal are limited to displaying text. As many terminal these days provide escape sequences to display non-text; bringing this loved feature to IPython CLI made a lot of sens. This functionality will not only allow inline images; but allow opening of external program; for example mplayer to "display" sound files.

So far only the hooks necessary for this are in place, but no default mime renderers added; so inline images will only be available via extensions. We will progressively enable these features by default in the next few releases, and contribution is welcomed.

We welcome any feedback on the API. See shell_mimerenderer for more informations.

This is originally based on work form in 10610 from @stephanh42 started over two years ago, and still a lot need to be done.

MISC

  • Completions can define their own ordering 11855
  • Enable Plotting in the same cell than the one that import matplotlib 11916
  • Allow to store and restore multiple variables at once 11930

You can see all pull-requests for this release.

API Changes

Change of API and exposed objects automatically detected using frappuccino (still in beta):

The following items are new in IPython 7.10:

+ IPython.terminal.shortcuts.reformat_text_before_cursor(buffer, document, shell)
+ IPython.terminal.interactiveshell.PTK3
+ IPython.terminal.interactiveshell.black_reformat_handler(text_before_cursor)
+ IPython.terminal.prompts.RichPromptDisplayHook.write_format_data(self, format_dict, md_dict='None')

The following items have been removed in 7.10:

- IPython.lib.pretty.DICT_IS_ORDERED

The following signatures differ between versions:

- IPython.extensions.storemagic.restore_aliases(ip)
+ IPython.extensions.storemagic.restore_aliases(ip, alias='None')

Special Thanks

  • @stephanh42 who started the work on inline images in terminal 2 years ago
  • @augustogoulart who spent a lot of time triaging issues and responding to users.
  • @con-f-use who is my (@Carreau) first sponsor on GitHub, as a reminder if you like IPython, Jupyter and many other library of the SciPy stack you can donate to numfocus.org non profit

IPython 7.9.0

IPython 7.9 is a small release with a couple of improvement and bug fixes.

  • Xterm terminal title should be restored on exit 11910
  • special variables _,__, ___ are not set anymore when cache size is 0 or less. 11877
  • Autoreload should have regained some speed by using a new heuristic logic to find all objects needing reload. This should avoid large objects traversal like pandas dataframes. 11876
  • Get ready for Python 4. 11874
  • %env Magic now has heuristic to hide potentially sensitive values 11896

This is a small release despite a number of Pull Request Pending that need to be reviewed/worked on. Many of the core developers have been busy outside of IPython/Jupyter and we thanks all contributor for their patience; we'll work on these as soon as we have time.

IPython 7.8.0

IPython 7.8.0 contain a few bugfix and 2 new APIs:

  • Enable changing the font color for LaTeX rendering 11840
  • and Re-Expose some PDB API (see below)

Expose Pdb API

Expose the built-in pdb.Pdb API. Pdb constructor arguments are generically exposed, regardless of python version. Newly exposed arguments:

  • skip - Python 3.1+
  • nosiginnt - Python 3.2+
  • readrc - Python 3.6+

Try it out:

from IPython.terminal.debugger import TerminalPdb
pdb = TerminalPdb(skip=["skipthismodule"])

See 11840

IPython 7.7.0

IPython 7.7.0 contain multiple bug fixes and documentation updates; Here are a few of the outstanding issue fixed:

  • Fix a bug introduced in 7.6 where the %matplotlib magic would fail on previously acceptable arguments 11814.
  • Fix the manage location on freebsd 11808.
  • Fix error message about aliases after %reset call in ipykernel 11806
  • Fix Duplication completions in emacs 11803

We are planning to adopt NEP29 (still currently in draft) which may make this minor version of IPython the last one to support Python 3.5 and will make the code base more aggressive toward removing compatibility with older versions of Python.

GitHub now support to give only "Triage" permissions to users; if you'd like to help close stale issues and labels issues please reach to us with your GitHub Username and we'll add you to the triage team. It is a great way to start contributing and a path toward getting commit rights.

IPython 7.6.1

IPython 7.6.1 contain a critical bugfix in the %timeit magic, which would crash on some inputs as a side effect of 11716. See 11812

IPython 7.6.0

IPython 7.6.0 contains a couple of bug fixes and number of small features additions as well as some compatibility with the current development version of Python 3.8.

  • Add a -l option to psearch to list the available search types. 11672
  • Support PathLike for DisplayObject and Image. 11764
  • Configurability of timeout in the test suite for slow platforms. 11756
  • Accept any casing for matplotlib backend. 121748
  • Properly skip test that requires numpy to be installed 11723
  • More support for Python 3.8 and positional only arguments (pep570) 11720
  • Unicode names for the completion are loaded lazily on first use which should decrease startup time. 11693
  • Autoreload now update the types of reloaded objects; this for example allow pickling of reloaded objects. 11644
  • Fix a bug where %%time magic would suppress cell output. 11716

Prepare migration to pytest (instead of nose) for testing

Most of the work between 7.5 and 7.6 was to prepare the migration from our testing framework to pytest. Most of the test suite should now work by simply issuing pytest from the root of the repository.

The migration to pytest is just at its beginning. Many of our test still rely on IPython-specific plugins for nose using pytest (doctest using IPython syntax is one example of this where test appear as "passing", while no code has been ran). Many test also need to be updated like yield-test to be properly parametrized tests.

Migration to pytest allowed me to discover a number of issues in our test suite; which was hiding a number of subtle issues – or not actually running some of the tests in our test suite – I have thus corrected many of those; like improperly closed resources; or used of deprecated features. I also made use of the pytest --durations=... to find some of our slowest test and speed them up (our test suite can now be up to 10% faster). Pytest as also a variety of plugins and flags which will make the code quality of IPython and the testing experience better.

Misc

We skipped the release of 7.6 at the end of May, but will attempt to get back on schedule. We are starting to think about making introducing backward incompatible change and start the 8.0 series.

Special Thanks to Gabriel (@gpotter2 on GitHub), who among other took care many of the remaining task for 7.4 and 7.5, like updating the website.

IPython 7.5.0

IPython 7.5.0 consist mostly of bug-fixes, and documentation updates, with one minor new feature. The Audio display element can now be assigned an element id when displayed in browser. See 11670

The major outstanding bug fix correct a change of behavior that was introduce in 7.4.0 where some cell magics would not be able to access or modify global scope when using the @needs_local_scope decorator. This was typically encountered with the %%time and %%timeit magics. See 11659 and 11698.

IPython 7.4.0

Unicode name completions

Previously, we provided completion for a unicode name with its relative symbol. With this, now IPython provides complete suggestions to unicode name symbols.

As on the PR, if user types \LAT<tab>, IPython provides a list of possible completions. In this case, it would be something like:

'LATIN CAPITAL LETTER A',
'LATIN CAPITAL LETTER B',
'LATIN CAPITAL LETTER C',
'LATIN CAPITAL LETTER D',
....

This help to type unicode character that do not have short latex aliases, and have long unicode names. for example Ͱ, \GREEK CAPITAL LETTER HETA.

This feature was contributed by Luciana Marques 11583.

Make audio normalization optional

Added 'normalize' argument to IPython.display.Audio. This argument applies when audio data is given as an array of samples. The default of normalize=True preserves prior behavior of normalizing the audio to the maximum possible range. Setting to False disables normalization.

Miscellaneous

  • Fix improper acceptation of return outside of functions. 11641.
  • Fixed PyQt 5.11 backwards incompatibility causing sip import failure. 11613.
  • Fix Bug where type? would crash IPython. 1608.
  • Allow to apply @needs_local_scope to cell magics for convenience. 11542.

IPython 7.3.0

IPython 7.3.0 bring several bug fixes and small improvements that you will described bellow.

The biggest change to this release is the implementation of the %conda and %pip magics, that will attempt to install packages in the current environment. You may still need to restart your interpreter or kernel for the change to be taken into account, but it should simplify installation of packages into remote environment. Installing using pip/conda from the command line is still the prefer method.

The %pip magic was already present, but was only printing a warning; now it will actually forward commands to pip.

Misc bug fixes and improvements:

  • Compatibility with Python 3.8.
  • Do not expand shell variable in execution magics, and added the no_var_expand decorator for magic requiring a similar functionality 11516
  • Add %pip and %conda magic 11524
  • Re-initialize posix aliases after a %reset 11528
  • Allow the IPython command line to run *.ipynb files 11529

IPython 7.2.0

IPython 7.2.0 brings minor bugfixes, improvements, and new configuration options:

  • Fix a bug preventing PySide2 GUI integration from working 11464
  • Run CI on Mac OS ! 11471
  • Fix IPython "Demo" mode. 11498
  • Fix %run magic with path in name 11499
  • Fix: add CWD to sys.path after stdlib 11502
  • Better rendering of signatures, especially long ones. 11505
  • Re-enable jedi by default if it's installed 11506
  • Add New minimal exception reporting mode (useful for educational purpose). See 11509

Added ability to show subclasses when using pinfo and other utilities

When using ?/?? on a class, IPython will now list the first 10 subclasses.

Special Thanks to Chris Mentzel of the Moore Foundation for this feature. Chris is one of the people who played a critical role in IPython/Jupyter getting funding.

We are grateful for all the help Chris has given us over the years, and we're now proud to have code contributed by Chris in IPython.

OSMagics.cd_force_quiet configuration option

You can set this option to force the %cd magic to behave as if -q was passed: :

In [1]: cd /
/

In [2]: %config OSMagics.cd_force_quiet = True

In [3]: cd /tmp

In [4]:

See 11491

In vi editing mode, whether the prompt includes the current vi mode can now be configured

Set the TerminalInteractiveShell.prompt_includes_vi_mode to a boolean value (default: True) to control this feature. See 11492

IPython 7.1.0

IPython 7.1.0 is the first minor release after 7.0.0 and mostly brings fixes to new features, internal refactoring, and fixes for regressions that happened during the 6.x->7.x transition. It also brings Compatibility with Python 3.7.1, as we're unwillingly relying on a bug in CPython.

New Core Dev:

  • We welcome Jonathan Slenders to the commiters. Jonathan has done a fantastic work on prompt_toolkit, and we'd like to recognise his impact by giving him commit rights. 11397

Notable Changes

  • Major update of "latex to unicode" tab completion map (see below)

Notable New Features:

  • Restore functionality and documentation of the sphinx directive, which is now stricter (fail on error by daefault), has new configuration options, has a brand new documentation page ipython_directive (which needs some cleanup). It is also now tested so we hope to have less regressions. 11402
  • IPython.display.Video now supports width and height arguments, allowing a custom width and height to be set instead of using the video's width and height. 11353
  • Warn when using HTML('<iframe>') instead of IFrame 11350
  • Allow Dynamic switching of editing mode between vi/emacs and show normal/input mode in prompt when using vi. 11390. Use %config TerminalInteractiveShell.editing_mode = 'vi' or %config TerminalInteractiveShell.editing_mode = 'emacs' to dynamically switch between modes.

Notable Fixes:

  • Fix entering of multi-line blocks in terminal IPython, and various crashes in the new input transformation machinery 11354, 11356, 11358. These also fix a Compatibility bug with Python 3.7.1.
  • Fix moving through generator stack in ipdb 11266
  • %Magic command arguments now support quoting. 11330
  • Re-add rprint and rprinte aliases. 11331
  • Remove implicit dependency on ipython_genutils 11317
  • Make nonlocal raise SyntaxError instead of silently failing in async mode. 11382
  • Fix mishandling of magics and = ! assignment just after a dedent in nested code blocks 11418
  • Fix instructions for custom shortcuts 11426

Notable Internals improvements:

  • Use of os.scandir (Python 3 only) to speed up some file system operations. 11365
  • use perf_counter instead of clock for more precise timing results with %time 11376

Many thanks to all the contributors and in particular to bartskowron and tonyfast who handled some pretty complicated bugs in the input machinery. We had a number of first time contributors and maybe hacktoberfest participants that made significant contributions and helped us free some time to focus on more complicated bugs.

You can see all the closed issues and Merged PR, new features and fixes here.

Unicode Completion update

In IPython 7.1 the Unicode completion map has been updated and synchronized with the Julia language.

Added and removed character characters:

\jmath (ȷ), \\underleftrightarrow (U+034D, combining) have been added, while \\textasciicaron have been removed

Some sequences have seen their prefix removed:

  • 6 characters \text...<tab> should now be inputed with \...<tab> directly,
  • 45 characters \Elz...<tab> should now be inputed with \...<tab> directly,
  • 65 characters \B...<tab> should now be inputed with \...<tab> directly,
  • 450 characters \m...<tab> should now be inputed with \...<tab> directly,

Some sequences have seen their prefix shortened:

  • 5 characters \mitBbb...<tab> should now be inputed with \bbi...<tab> directly,
  • 52 characters \mit...<tab> should now be inputed with \i...<tab> directly,
  • 216 characters \mbfit...<tab> should now be inputed with \bi...<tab> directly,
  • 222 characters \mbf...<tab> should now be inputed with \b...<tab> directly,

A couple of characters had their sequence simplified:

  • ð, type \dh<tab>, instead of \eth<tab>
  • ħ, type \hbar<tab>, instead of \Elzxh<tab>
  • ɸ, type \ltphi<tab>, instead of \textphi<tab>
  • ϴ, type \varTheta<tab>, instead of \textTheta<tab>
  • , type \eulermascheroni<tab>, instead of \Eulerconst<tab>
  • , type \planck<tab>, instead of \Planckconst<tab>
  • U+0336 (COMBINING LONG STROKE OVERLAY), type \strike<tab>, instead of \Elzbar<tab>.

A couple of sequences have been updated:

  • \varepsilon now gives ɛ (GREEK SMALL LETTER EPSILON) instead of ε (GREEK LUNATE EPSILON SYMBOL),
  • \underbar now gives U+0331 (COMBINING MACRON BELOW) instead of U+0332 (COMBINING LOW LINE).

IPython 7.0.0

Released Thursday September 27th, 2018

IPython 7 includes major feature improvements. This is also the second major version of IPython to support only Python 3 – starting at Python 3.4. Python 2 is still community-supported on the bugfix only 5.x branch, but we remind you that Python 2 "end of life" is on Jan 1st 2020.

We were able to backport bug fixes to the 5.x branch thanks to our backport bot which backported more than 70 Pull-Requests, but there are still many PRs that required manual work. This is an area of the project where you can easily contribute by looking for PRs that still need manual backport

The IPython 6.x branch will likely not see any further release unless critical bugs are found.

Make sure you have pip > 9.0 before upgrading. You should be able to update by running:

pip install ipython --upgrade

ipydev

If you are trying to install or update an alpha, beta, or rc version, use pip --pre flag.

pip install ipython --upgrade --pre

Or, if you have conda installed:

conda install ipython

Prompt Toolkit 2.0

IPython 7.0+ now uses prompt_toolkit 2.0. If you still need to use an earlier prompt_toolkit version, you may need to pin IPython to <7.0.

Autowait: Asynchronous REPL

Staring with IPython 7.0 on Python 3.6+, IPython can automatically await top level code. You should not need to access an event loop or runner yourself. To learn more, read the autoawait section of our docs, see 11265, or try the following code:

Python 3.6.0
Type 'copyright', 'credits' or 'license' for more information
IPython 7.0.0 -- An enhanced Interactive Python. Type '?' for help.

In [1]: import aiohttp
   ...: result = aiohttp.get('https://api.github.com')

In [2]: response = await result
<pause for a few 100s ms>

In [3]: await response.json()
Out[3]:
{'authorizations_url': 'https://api.github.com/authorizations',
 'code_search_url': 'https://api.github.com/search/code?q={query}{&page,per_page,sort,order}',
...
}

Note

Async integration is experimental code, behavior may change or be removed between Python and IPython versions without warnings.

Integration is by default with asyncio, but other libraries can be configured --like curio or trio -- to improve concurrency in the REPL:

In [1]: %autoawait trio

In [2]: import trio

In [3]: async def child(i):
   ...:     print("   child %s goes to sleep"%i)
   ...:     await trio.sleep(2)
   ...:     print("   child %s wakes up"%i)

In [4]: print('parent start')
   ...: async with trio.open_nursery() as n:
   ...:     for i in range(3):
   ...:         n.spawn(child, i)
   ...: print('parent end')
parent start
   child 2 goes to sleep
   child 0 goes to sleep
   child 1 goes to sleep
   <about 2 seconds pause>
   child 2 wakes up
   child 1 wakes up
   child 0 wakes up
parent end

See autoawait for more information.

Asynchronous code in a Notebook interface or any other frontend using the Jupyter Protocol will require further updates to the IPykernel package.

Non-Asynchronous code

As the internal API of IPython is now asynchronous, IPython needs to run under an event loop. In order to allow many workflows, (like using the %run magic, or copy-pasting code that explicitly starts/stop event loop), when top-level code is detected as not being asynchronous, IPython code is advanced via a pseudo-synchronous runner, and may not advance pending tasks.

Change to Nested Embed

The introduction of the ability to run async code had some effect on the IPython.embed() API. By default, embed will not allow you to run asynchronous code unless an event loop is specified.

Effects on Magics

Some magics will not work with async until they're updated. Contributions welcome.

Expected Future changes

We expect more internal but public IPython functions to become async, and will likely end up having a persistent event loop while IPython is running.

Thanks

This release took more than a year in the making. The code was rebased a number of times; leading to commit authorship that may have been lost in the final Pull-Request. Huge thanks to many people for contribution, discussion, code, documentation, use-cases: dalejung, danielballan, ellisonbg, fperez, gnestor, minrk, njsmith, pganssle, tacaswell, takluyver , vidartf ... And many others.

Autoreload Improvement

The magic %autoreload 2 <autoreload> now captures new methods added to classes. Earlier, only methods existing as of the initial import were being tracked and updated.

This new feature helps dual environment development - Jupyter+IDE - where the code gradually moves from notebook cells to package files as it gets structured.

Example: An instance of the class MyClass will be able to access the method cube() after it is uncommented and the file file1.py is saved on disk.

# notebook

from mymodule import MyClass
first = MyClass(5)
# mymodule/file1.py

class MyClass:

    def __init__(self, a=10):
        self.a = a

    def square(self):
        print('compute square')
        return self.a*self.a

    # def cube(self):
    #     print('compute cube')
    #     return self.a*self.a*self.a

Misc

The autoindent feature that was deprecated in 5.x was re-enabled and un-deprecated in 11257

Make %run -n -i ... <run> work correctly. Earlier, if %run was passed both arguments, -n would be silently ignored. See 10308

The %%script (as well as %%bash, %%ruby... ) cell magics now raise by default if the return code of the given code is non-zero (thus halting execution of further cells in a notebook). The behavior can be disable by passing the --no-raise-error flag.

Deprecations

A couple of unused functions and methods have been deprecated and will be removed in future versions:

  • IPython.utils.io.raw_print_err
  • IPython.utils.io.raw_print

Backwards incompatible changes

  • The API for transforming input before it is parsed as Python code has been completely redesigned: any custom input transformations will need to be rewritten. See /config/inputtransforms for details of the new API.