bpo-42139: Update What's New 3.9 for master (#22936)
This commit is contained in:
Terry Jan Reedy
GitHub
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805ef73ad0
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@ -4,22 +4,21 @@
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:Release: |release|
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:Date: |today|
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:Editor: Łukasz Langa
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.. Rules for maintenance:
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* Anyone can add text to this document. Do not spend very much time
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on the wording of your changes, because your text will probably
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get rewritten to some degree.
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* Anyone can add text to this document. Your text might get
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rewritten to some degree.
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* The maintainer will go through Misc/NEWS periodically and add
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changes; it's therefore more important to add your changes to
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Misc/NEWS than to this file.
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* This is not a complete list of every single change; completeness
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is the purpose of Misc/NEWS. Some changes I consider too small
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is the purpose of Misc/NEWS. Some changes will be too small
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or esoteric to include. If such a change is added to the text,
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I'll just remove it. (This is another reason you shouldn't spend
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too much time on writing your addition.)
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it might get removed during final editing.
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* If you want to draw your new text to the attention of the
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maintainer, add 'XXX' to the beginning of the paragraph or
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@ -46,14 +45,13 @@
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when researching a change.
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This article explains the new features in Python 3.9, compared to 3.8.
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Python 3.9 was released on October 5th, 2020.
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For full details, see the :ref:`changelog <changelog>`.
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.. note::
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.. seealso::
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Prerelease users should be aware that this document is currently in draft
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form. It will be updated substantially as Python 3.9 moves towards release,
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so it's worth checking back even after reading earlier versions.
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:pep:`596` - Python 3.9 Release Schedule
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Summary -- Release highlights
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@ -62,27 +60,70 @@ Summary -- Release highlights
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.. This section singles out the most important changes in Python 3.9.
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Brevity is key.
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New syntax features:
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.. PEP-sized items next.
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* :pep:`584`, union operators added to ``dict``;
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* :pep:`585`, type hinting generics in standard collections;
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* :pep:`614`, relaxed grammar restrictions on decorators.
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New built-in features:
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* :pep:`616`, string methods to remove prefixes and suffixes.
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New features in the standard library:
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* :pep:`593`, flexible function and variable annotations;
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* :func:`os.pidfd_open` added that allows process management without races
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and signals.
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Interpreter improvements:
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* :pep:`573`, fast access to module state from methods of C extension
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types;
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* :pep:`617`, CPython now uses a new parser based on PEG;
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* a number of Python builtins (range, tuple, set, frozenset, list, dict) are
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now sped up using :pep:`590` vectorcall;
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* garbage collection does not block on resurrected objects;
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* a number of Python modules (:mod:`_abc`, :mod:`audioop`, :mod:`_bz2`,
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:mod:`_codecs`, :mod:`_contextvars`, :mod:`_crypt`, :mod:`_functools`,
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:mod:`_json`, :mod:`_locale`, :mod:`math`, :mod:`operator`, :mod:`resource`,
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:mod:`time`, :mod:`_weakref`) now use multiphase initialization as defined
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by PEP 489;
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* a number of standard library modules (:mod:`audioop`, :mod:`ast`, :mod:`grp`,
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:mod:`_hashlib`, :mod:`pwd`, :mod:`_posixsubprocess`, :mod:`random`,
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:mod:`select`, :mod:`struct`, :mod:`termios`, :mod:`zlib`) are now using
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the stable ABI defined by PEP 384.
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New library modules:
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* :pep:`615`, the IANA Time Zone Database is now present in the standard
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library in the :mod:`zoneinfo` module;
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* an implementation of a topological sort of a graph is now provided in
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the new :mod:`graphlib` module.
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Release process changes:
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* :pep:`602`, CPython adopts an annual release cycle.
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You should check for DeprecationWarning in your code
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====================================================
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When Python 2.7 was still supported, many functions were kept for backward
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compatibility with Python 2.7. With the end of Python 2.7 support, these
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backward compatibility layers have been removed, or will be removed soon.
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Most of them emitted a :exc:`DeprecationWarning` warning for several years. For
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example, using ``collections.Mapping`` instead of ``collections.abc.Mapping``
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emits a :exc:`DeprecationWarning` since Python 3.3, released in 2012.
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When Python 2.7 was still supported, a lot of functionality in Python 3
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was kept for backward compatibility with Python 2.7. With the end of Python
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2 support, these backward compatibility layers have been removed, or will
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be removed soon. Most of them emitted a :exc:`DeprecationWarning` warning for
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several years. For example, using ``collections.Mapping`` instead of
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``collections.abc.Mapping`` emits a :exc:`DeprecationWarning` since Python
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3.3, released in 2012.
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Test your application with the :option:`-W` ``default`` command-line option to see
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:exc:`DeprecationWarning` and :exc:`PendingDeprecationWarning`, or even with
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:option:`-W` ``error`` to treat them as errors. :ref:`Warnings Filter
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<warning-filter>` can be used to ignore warnings from third-party code.
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It has been decided to keep a few backward compatibility layers for one last
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release, to give more time to Python projects maintainers to organize the
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Python 3.9 is the last version providing those Python 2 backward compatibility
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layers, to give more time to Python projects maintainers to organize the
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removal of the Python 2 support and add support for Python 3.9.
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Aliases to :ref:`Abstract Base Classes <collections-abstract-base-classes>` in
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@ -94,6 +135,9 @@ More generally, try to run your tests in the :ref:`Python Development Mode
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<devmode>` which helps to prepare your code to make it compatible with the
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next Python version.
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Note: a number of pre-existing deprecatations were removed in this version
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of Python as well. Consult the :ref:`removed-in-python-39` section.
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New Features
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============
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@ -102,11 +146,23 @@ Dictionary Merge & Update Operators
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-----------------------------------
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Merge (``|``) and update (``|=``) operators have been added to the built-in
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:class:`dict` class. See :pep:`584` for a full description.
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:class:`dict` class. Those complement the existing ``dict.update`` and
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``{**d1, **d2}`` methods of merging dictionaries.
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Example::
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>>> x = {"key1": "value1 from x", "key2": "value2 from x"}
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>>> y = {"key2": "value2 from y", "key3": "value3 from y"}
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>>> x | y
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{'key1': 'value1 from x', 'key2': 'value2 from y', 'key3': 'value3 from y'}
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>>> y | x
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{'key2': 'value2 from x', 'key3': 'value3 from y', 'key1': 'value1 from x'}
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See :pep:`584` for a full description.
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(Contributed by Brandt Bucher in :issue:`36144`.)
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PEP 616: New removeprefix() and removesuffix() string methods
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-------------------------------------------------------------
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New String Methods to Remove Prefixes and Suffixes
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--------------------------------------------------
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:meth:`str.removeprefix(prefix)<str.removeprefix>` and
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:meth:`str.removesuffix(suffix)<str.removesuffix>` have been added
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@ -115,8 +171,8 @@ to easily remove an unneeded prefix or a suffix from a string. Corresponding
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added. See :pep:`616` for a full description. (Contributed by Dennis Sweeney in
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:issue:`39939`.)
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PEP 585: Builtin Generic Types
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------------------------------
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Type Hinting Generics in Standard Collections
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---------------------------------------------
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In type annotations you can now use built-in collection types such as
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``list`` and ``dict`` as generic types instead of importing the
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@ -135,8 +191,8 @@ Example:
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See :pep:`585` for more details. (Contributed by Guido van Rossum,
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Ethan Smith, and Batuhan Taşkaya in :issue:`39481`.)
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PEP 617: New Parser
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-------------------
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New Parser
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----------
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Python 3.9 uses a new parser, based on `PEG
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<https://en.wikipedia.org/wiki/Parsing_expression_grammar>`_ instead
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@ -167,7 +223,6 @@ Other Language Changes
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its top-level package.
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(Contributed by Ngalim Siregar in :issue:`37444`.)
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* Python now gets the absolute path of the script filename specified on
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the command line (ex: ``python3 script.py``): the ``__file__`` attribute of
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the :mod:`__main__` module became an absolute path, rather than a relative
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@ -201,6 +256,17 @@ Other Language Changes
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for the correspondent concrete type (``list`` in this case).
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(Contributed by Serhiy Storchaka in :issue:`40257`.)
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* Parallel running of :meth:`~agen.aclose` / :meth:`~agen.asend` /
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:meth:`~agen.athrow` is now prohibited, and ``ag_running`` now reflects
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the actual running status of the async generator.
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(Contributed by Yury Selivanov in :issue:`30773`.)
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* Unexpected errors in calling the ``__iter__`` method are no longer masked by
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``TypeError`` in the :keyword:`in` operator and functions
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:func:`~operator.contains`, :func:`~operator.indexOf` and
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:func:`~operator.countOf` of the :mod:`operator` module.
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(Contributed by Serhiy Storchaka in :issue:`40824`.)
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New Modules
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===========
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@ -248,9 +314,10 @@ PyPI and maintained by the CPython core team.
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graphlib
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---------
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Add the :mod:`graphlib` that contains the :class:`graphlib.TopologicalSorter` class
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to offer functionality to perform topological sorting of graphs. (Contributed by Pablo
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Galindo, Tim Peters and Larry Hastings in :issue:`17005`.)
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A new module, :mod:`graphlib`, was added that contains the
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:class:`graphlib.TopologicalSorter` class to offer functionality to perform
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topological sorting of graphs. (Contributed by Pablo Galindo, Tim Peters and
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Larry Hastings in :issue:`17005`.)
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Improved Modules
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@ -296,6 +363,15 @@ loop, and essentially works as a high-level version of
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:meth:`~asyncio.loop.run_in_executor` that can directly take keyword arguments.
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(Contributed by Kyle Stanley and Yury Selivanov in :issue:`32309`.)
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When cancelling the task due to a timeout, :meth:`asyncio.wait_for` will now
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wait until the cancellation is complete also in the case when *timeout* is
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<= 0, like it does with positive timeouts.
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(Contributed by Elvis Pranskevichus in :issue:`32751`.)
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:mod:`asyncio` now raises :exc:`TyperError` when calling incompatible
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methods with an :class:`ssl.SSLSocket` socket.
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(Contributed by Ido Michael in :issue:`37404`.)
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compileall
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----------
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@ -328,7 +404,7 @@ startup overhead and reduces the amount of lost CPU time to idle workers.
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curses
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------
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Add :func:`curses.get_escdelay`, :func:`curses.set_escdelay`,
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Added :func:`curses.get_escdelay`, :func:`curses.set_escdelay`,
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:func:`curses.get_tabsize`, and :func:`curses.set_tabsize` functions.
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(Contributed by Anthony Sottile in :issue:`38312`.)
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@ -375,12 +451,17 @@ finalized by the garbage collector. (Contributed by Pablo Galindo in
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hashlib
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-------
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The :mod:`hashlib` module can now use SHA3 hashes and SHAKE XOF from OpenSSL
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when available.
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(Contributed by Christian Heimes in :issue:`37630`.)
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Builtin hash modules can now be disabled with
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``./configure --without-builtin-hashlib-hashes`` or selectively enabled with
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e.g. ``./configure --with-builtin-hashlib-hashes=sha3,blake2`` to force use
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of OpenSSL based implementation.
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(Contributed by Christian Heimes in :issue:`40479`)
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http
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----
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@ -390,13 +471,13 @@ HTTP status codes ``103 EARLY_HINTS``, ``418 IM_A_TEAPOT`` and ``425 TOO_EARLY``
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IDLE and idlelib
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----------------
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Add option to toggle cursor blink off. (Contributed by Zackery Spytz
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Added option to toggle cursor blink off. (Contributed by Zackery Spytz
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in :issue:`4603`.)
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Escape key now closes IDLE completion windows. (Contributed by Johnny
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Najera in :issue:`38944`.)
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Add keywords to module name completion list. (Contributed by Terry J.
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Added keywords to module name completion list. (Contributed by Terry J.
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Reedy in :issue:`37765`.)
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The changes above have been backported to 3.8 maintenance releases.
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@ -426,6 +507,17 @@ now raises :exc:`ImportError` instead of :exc:`ValueError` for invalid relative
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import attempts.
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(Contributed by Ngalim Siregar in :issue:`37444`.)
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Import loaders which publish immutable module objects can now publish
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immutable packages in addition to individual modules.
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(Contributed by Dino Viehland in :issue:`39336`.)
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Added :func:`importlib.resources.files` function with support for
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subdirectories in package data, matching backport in ``importlib_resources``
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version 1.5.
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(Contributed by Jason R. Coombs in :issue:`39791`.)
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Refreshed ``importlib.metadata`` from ``importlib_metadata`` version 1.6.1.
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inspect
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-------
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@ -448,15 +540,15 @@ Expanded the :func:`math.gcd` function to handle multiple arguments.
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Formerly, it only supported two arguments.
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(Contributed by Serhiy Storchaka in :issue:`39648`.)
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Add :func:`math.lcm`: return the least common multiple of specified arguments.
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Added :func:`math.lcm`: return the least common multiple of specified arguments.
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(Contributed by Mark Dickinson, Ananthakrishnan and Serhiy Storchaka in
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:issue:`39479` and :issue:`39648`.)
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Add :func:`math.nextafter`: return the next floating-point value after *x*
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Added :func:`math.nextafter`: return the next floating-point value after *x*
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towards *y*.
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(Contributed by Victor Stinner in :issue:`39288`.)
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Add :func:`math.ulp`: return the value of the least significant bit
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Added :func:`math.ulp`: return the value of the least significant bit
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of a float.
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(Contributed by Victor Stinner in :issue:`39310`.)
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@ -492,7 +584,7 @@ The :func:`os.putenv` and :func:`os.unsetenv` functions are now always
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available.
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(Contributed by Victor Stinner in :issue:`39395`.)
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Add :func:`os.waitstatus_to_exitcode` function:
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Added :func:`os.waitstatus_to_exitcode` function:
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convert a wait status to an exit code.
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(Contributed by Victor Stinner in :issue:`40094`.)
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@ -503,6 +595,12 @@ Added :meth:`pathlib.Path.readlink()` which acts similarly to
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:func:`os.readlink`.
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(Contributed by Girts Folkmanis in :issue:`30618`)
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pdb
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---
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On Windows now :class:`~pdb.Pdb` supports ``~/.pdbrc``.
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(Contributed by Tim Hopper and Dan Lidral-Porter in :issue:`20523`.)
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poplib
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------
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@ -526,7 +624,7 @@ method etc, but for any object that has its own ``__doc__`` attribute.
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random
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------
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|
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Add a new :attr:`random.Random.randbytes` method: generate random bytes.
|
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Added a new :attr:`random.Random.randbytes` method: generate random bytes.
|
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(Contributed by Victor Stinner in :issue:`40286`.)
|
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|
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signal
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@ -555,6 +653,11 @@ constant on Linux 4.1 and greater.
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The socket module now supports the :data:`~socket.CAN_J1939` protocol on
|
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platforms that support it. (Contributed by Karl Ding in :issue:`40291`.)
|
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|
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The socket module now has the :func:`socket.send_fds` and
|
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:func:`socket.recv.fds` methods. (Contributed by Joannah Nanjekye, Shinya
|
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Okano and Victor Stinner in :issue:`28724`.)
|
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|
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|
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time
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----
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|
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|
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@ -566,7 +669,7 @@ which has nanosecond resolution, rather than
|
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sys
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---
|
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|
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Add a new :attr:`sys.platlibdir` attribute: name of the platform-specific
|
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Added a new :attr:`sys.platlibdir` attribute: name of the platform-specific
|
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library directory. It is used to build the path of standard library and the
|
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paths of installed extension modules. It is equal to ``"lib"`` on most
|
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platforms. On Fedora and SuSE, it is equal to ``"lib64"`` on 64-bit platforms.
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|
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@ -630,7 +733,7 @@ Optimizations
|
|||
|
||||
(Contributed by Serhiy Storchaka in :issue:`32856`.)
|
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|
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* Optimize signal handling in multithreaded applications. If a thread different
|
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* Optimized signal handling in multithreaded applications. If a thread different
|
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than the main thread gets a signal, the bytecode evaluation loop is no longer
|
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interrupted at each bytecode instruction to check for pending signals which
|
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cannot be handled. Only the main thread of the main interpreter can handle
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@ -640,10 +743,36 @@ Optimizations
|
|||
until the main thread handles signals.
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(Contributed by Victor Stinner in :issue:`40010`.)
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* Optimize the :mod:`subprocess` module on FreeBSD using ``closefrom()``.
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* Optimized the :mod:`subprocess` module on FreeBSD using ``closefrom()``.
|
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(Contributed by Ed Maste, Conrad Meyer, Kyle Evans, Kubilay Kocak and Victor
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Stinner in :issue:`38061`.)
|
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|
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* :c:func:`PyLong_FromDouble` is now up to 1.87x faster for values that
|
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fit into :c:type:`long`.
|
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(Contributed by Sergey Fedoseev in :issue:`37986`.)
|
||||
|
||||
* A number of Python builtins (:class:`range`, :class:`tuple`, :class:`set`,
|
||||
:class:`frozenset`, :class:`list`, :class:`dict`) are now sped up by using
|
||||
:pep:`590` vectorcall protocol.
|
||||
(Contributed by Dong-hee Na, Mark Shannon, Jeroen Demeyer and Petr Viktorin in :issue:`37207`.)
|
||||
|
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* Optimized :func:`~set.difference_update` for the case when the other set
|
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is much larger than the base set.
|
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(Suggested by Evgeny Kapun with code contributed by Michele Orrù in :issue:`8425`.)
|
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|
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* Python's small object allocator (``obmalloc.c``) now allows (no more than)
|
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one empty arena to remain available for immediate reuse, without returning
|
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it to the OS. This prevents thrashing in simple loops where an arena could
|
||||
be created and destroyed anew on each iteration.
|
||||
(Contributed by Tim Peters in :issue:`37257`.)
|
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|
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* :term:`floor division` of float operation now has a better performance. Also
|
||||
the message of :exc:`ZeroDivisionError` for this operation is updated.
|
||||
(Contributed by Dong-hee Na in :issue:`39434`.)
|
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|
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* Decoding short ASCII strings with UTF-8 and ascii codecs is now about
|
||||
15% faster. (Contributed by Inada Naoki in :issue:`37348`.)
|
||||
|
||||
Here's a summary of performance improvements from Python 3.4 through Python 3.9:
|
||||
|
||||
.. code-block:: none
|
||||
|
|
@ -699,10 +828,6 @@ in nanoseconds. The benchmarks were measured on an
|
|||
running the macOS 64-bit builds found at
|
||||
`python.org <https://www.python.org/downloads/mac-osx/>`_.
|
||||
|
||||
* A number of Python builtins (:class:`range`, :class:`tuple`, :class:`set`, :class:`frozenset`, :class:`list`, :class:`dict`)
|
||||
are now sped up by using :pep:`590` vectorcall protocol.
|
||||
(Contributed by Dong-hee Na, Mark Shannon, Jeroen Demeyer and Petr Viktorin in :issue:`37207`.)
|
||||
|
||||
|
||||
Deprecated
|
||||
==========
|
||||
|
|
@ -784,6 +909,9 @@ Deprecated
|
|||
* Passing ``None`` as the first argument to the :func:`shlex.split` function
|
||||
has been deprecated. (Contributed by Zackery Spytz in :issue:`33262`.)
|
||||
|
||||
* :func:`smtpd.MailmanProxy` is now deprecated as it is unusable without
|
||||
an external module, ``mailman``. (Contributed by Samuel Colvin in :issue:`35800`.)
|
||||
|
||||
* The :mod:`lib2to3` module now emits a :exc:`PendingDeprecationWarning`.
|
||||
Python 3.9 switched to a PEG parser (see :pep:`617`), and Python 3.10 may
|
||||
include new language syntax that is not parsable by lib2to3's LL(1) parser.
|
||||
|
|
@ -798,6 +926,8 @@ Deprecated
|
|||
.. _LibCST: https://libcst.readthedocs.io/
|
||||
.. _parso: https://parso.readthedocs.io/
|
||||
|
||||
.. _removed-in-python-39:
|
||||
|
||||
Removed
|
||||
=======
|
||||
|
||||
|
|
@ -967,6 +1097,19 @@ Changes in the Python API
|
|||
of ``wchar_t`` since Python 3.3.
|
||||
(Contributed by Inada Naoki in :issue:`34538`.)
|
||||
|
||||
* The :func:`logging.getLogger` API now returns the root logger when passed
|
||||
the name ``'root'``, whereas previously it returned a non-root logger named
|
||||
``'root'``. This could affect cases where user code explicitly wants a
|
||||
non-root logger named ``'root'``, or instantiates a logger using
|
||||
``logging.getLogger(__name__)`` in some top-level module called ``'root.py'``.
|
||||
(Contributed by Vinay Sajip in :issue:`37742`.)
|
||||
|
||||
* Division handling of :class:`~pathlib.PurePath` now returns ``NotImplemented``
|
||||
instead of raising a :exc:`TypeError` when passed something other than an
|
||||
instance of ``str`` or :class:`~pathlib.PurePath`. This allows creating
|
||||
compatible classes that don't inherit from those mentioned types.
|
||||
(Contributed by Roger Aiudi in :issue:`34775`).
|
||||
|
||||
|
||||
Changes in the C API
|
||||
--------------------
|
||||
|
|
@ -1017,6 +1160,11 @@ Changes in the C API
|
|||
|
||||
(See :issue:`35810` and :issue:`40217` for more information.)
|
||||
|
||||
* The functions ``PyEval_CallObject``, ``PyEval_CallFunction``,
|
||||
``PyEval_CallMethod`` and ``PyEval_CallObjectWithKeywords`` are deprecated.
|
||||
Use :c:func:`PyObject_Call` and its variants instead.
|
||||
(See more details in :issue:`29548`.)
|
||||
|
||||
CPython bytecode changes
|
||||
------------------------
|
||||
|
||||
|
|
@ -1025,11 +1173,21 @@ CPython bytecode changes
|
|||
correctly if the :exc:`AssertionError` exception was being shadowed.
|
||||
(Contributed by Zackery Spytz in :issue:`34880`.)
|
||||
|
||||
* The :opcode:`COMPARE_OP` opcode was split into four distinct instructions:
|
||||
|
||||
* ``COMPARE_OP`` for rich comparisons
|
||||
* ``IS_OP`` for 'is' and 'is not' tests
|
||||
* ``CONTAINS_OP`` for 'in' and 'not in' tests
|
||||
* ``JUMP_IF_NOT_EXC_MATCH`` for checking exceptions in 'try-except'
|
||||
statements.
|
||||
|
||||
(Contributed by Mark Shannon in :issue:`39156`.)
|
||||
|
||||
|
||||
Build Changes
|
||||
=============
|
||||
|
||||
* Add ``--with-platlibdir`` option to the ``configure`` script: name of the
|
||||
* Added ``--with-platlibdir`` option to the ``configure`` script: name of the
|
||||
platform-specific library directory, stored in the new :attr:`sys.platlibdir`
|
||||
attribute. See :attr:`sys.platlibdir` attribute for more information.
|
||||
(Contributed by Jan Matějek, Matěj Cepl, Charalampos Stratakis
|
||||
|
|
@ -1042,6 +1200,34 @@ Build Changes
|
|||
functions are now required to build Python.
|
||||
(Contributed by Victor Stinner in :issue:`39395`.)
|
||||
|
||||
* On non-Windows platforms, creating ``bdist_wininst`` installers is now
|
||||
officially unsupported. (See :issue:`10945` for more details.)
|
||||
|
||||
* When building Python on macOS from source, ``_tkinter`` now links with
|
||||
non-system Tcl and Tk frameworks if they are installed in
|
||||
``/Library/Frameworks``, as had been the case on older releases
|
||||
of macOS. If a macOS SDK is explicitly configured, by using
|
||||
``--enable-universalsdk=`` or ``-isysroot``, only the SDK itself is
|
||||
searched. The default behavior can still be overridden with
|
||||
``--with-tcltk-includes`` and ``--with-tcltk-libs``.
|
||||
(Contributed by Ned Deily in :issue:`34956`.)
|
||||
|
||||
* Python can now be built for Windows 10 ARM64.
|
||||
(Contributed by Steve Dower in :issue:`33125`.)
|
||||
|
||||
* Some individual tests are now skipped when ``--pgo`` is used. The tests
|
||||
in question increased the PGO task time significantly and likely
|
||||
didn't help improve optimization of the final executable. This
|
||||
speeds up the task by a factor of about 15x. Running the full unit test
|
||||
suite is slow. This change may result in a slightly less optimized build
|
||||
since not as many code branches will be executed. If you are willing to
|
||||
wait for the much slower build, the old behavior can be restored using
|
||||
``./configure [..] PROFILE_TASK="-m test --pgo-extended"``. We make no
|
||||
guarantees as to which PGO task set produces a faster build. Users who care
|
||||
should run their own relevant benchmarks as results can depend on the
|
||||
environment, workload, and compiler tool chain.
|
||||
(See :issue:`36044` and :issue:`37707` for more details.)
|
||||
|
||||
|
||||
C API Changes
|
||||
=============
|
||||
|
|
@ -1049,29 +1235,29 @@ C API Changes
|
|||
New Features
|
||||
------------
|
||||
|
||||
* :pep:`573`: Add :c:func:`PyType_FromModuleAndSpec` to associate
|
||||
* :pep:`573`: Added :c:func:`PyType_FromModuleAndSpec` to associate
|
||||
a module with a class; :c:func:`PyType_GetModule` and
|
||||
:c:func:`PyType_GetModuleState` to retrieve the module and its state; and
|
||||
:c:data:`PyCMethod` and :c:data:`METH_METHOD` to allow a method to
|
||||
access the class it was defined in.
|
||||
(Contributed by Marcel Plch and Petr Viktorin in :issue:`38787`.)
|
||||
|
||||
* Add :c:func:`PyFrame_GetCode` function: get a frame code.
|
||||
Add :c:func:`PyFrame_GetBack` function: get the frame next outer frame.
|
||||
* Added :c:func:`PyFrame_GetCode` function: get a frame code.
|
||||
Added :c:func:`PyFrame_GetBack` function: get the frame next outer frame.
|
||||
(Contributed by Victor Stinner in :issue:`40421`.)
|
||||
|
||||
* Add :c:func:`PyFrame_GetLineNumber` to the limited C API.
|
||||
* Added :c:func:`PyFrame_GetLineNumber` to the limited C API.
|
||||
(Contributed by Victor Stinner in :issue:`40421`.)
|
||||
|
||||
* Add :c:func:`PyThreadState_GetInterpreter` and
|
||||
* Added :c:func:`PyThreadState_GetInterpreter` and
|
||||
:c:func:`PyInterpreterState_Get` functions to get the interpreter.
|
||||
Add :c:func:`PyThreadState_GetFrame` function to get the current frame of a
|
||||
Added :c:func:`PyThreadState_GetFrame` function to get the current frame of a
|
||||
Python thread state.
|
||||
Add :c:func:`PyThreadState_GetID` function: get the unique identifier of a
|
||||
Added :c:func:`PyThreadState_GetID` function: get the unique identifier of a
|
||||
Python thread state.
|
||||
(Contributed by Victor Stinner in :issue:`39947`.)
|
||||
|
||||
* Add a new public :c:func:`PyObject_CallNoArgs` function to the C API, which
|
||||
* Added a new public :c:func:`PyObject_CallNoArgs` function to the C API, which
|
||||
calls a callable Python object without any arguments. It is the most efficient
|
||||
way to call a callable Python object without any argument.
|
||||
(Contributed by Victor Stinner in :issue:`37194`.)
|
||||
|
|
@ -1093,11 +1279,15 @@ New Features
|
|||
to a module.
|
||||
(Contributed by Dong-hee Na in :issue:`40024`.)
|
||||
|
||||
* Add the functions :c:func:`PyObject_GC_IsTracked` and
|
||||
* Added the functions :c:func:`PyObject_GC_IsTracked` and
|
||||
:c:func:`PyObject_GC_IsFinalized` to the public API to allow to query if
|
||||
Python objects are being currently tracked or have been already finalized by
|
||||
the garbage collector respectively. (Contributed by Pablo Galindo in
|
||||
:issue:`40241`.)
|
||||
the garbage collector respectively.
|
||||
(Contributed by Pablo Galindo Salgado in :issue:`40241`.)
|
||||
|
||||
* Added :c:func:`_PyObject_FunctionStr` to get a user-friendly string
|
||||
representation of a function-like object.
|
||||
(Patch by Jeroen Demeyer in :issue:`37645`.)
|
||||
|
||||
|
||||
Porting to Python 3.9
|
||||
|
|
@ -1144,10 +1334,44 @@ Porting to Python 3.9
|
|||
Python 3.3.
|
||||
(Contributed by Inada Naoki in :issue:`36346`.)
|
||||
|
||||
* The :c:func:`Py_FatalError` function is replaced with a macro which logs
|
||||
automatically the name of the current function, unless the
|
||||
``Py_LIMITED_API`` macro is defined.
|
||||
(Contributed by Victor Stinner in :issue:`39882`.)
|
||||
|
||||
* The vectorcall protocol now requires that the caller passes only strings as
|
||||
keyword names. (See :issue:`37540` for more information.)
|
||||
|
||||
* Implementation details of a number of macros and functions are now hidden:
|
||||
|
||||
* :c:func:`PyObject_IS_GC` macro was converted to a function.
|
||||
|
||||
* The :c:func:`PyObject_NEW` macro becomes an alias to the
|
||||
:c:func:`PyObject_New` macro, and the :c:func:`PyObject_NEW_VAR` macro
|
||||
becomes an alias to the :c:func:`PyObject_NewVar` macro. They no longer
|
||||
access directly the :c:member:`PyTypeObject.tp_basicsize` member.
|
||||
|
||||
* :c:func:`PyType_HasFeature` now always calls :c:func:`PyType_GetFlags`.
|
||||
Previously, it accessed directly the :c:member:`PyTypeObject.tp_flags`
|
||||
member when the limited C API was not used.
|
||||
|
||||
* :c:func:`PyObject_GET_WEAKREFS_LISTPTR` macro was converted to a function:
|
||||
the macro accessed directly the :c:member:`PyTypeObject.tp_weaklistoffset`
|
||||
member.
|
||||
|
||||
* :c:func:`PyObject_CheckBuffer` macro was converted to a function: the macro
|
||||
accessed directly the :c:member:`PyTypeObject.tp_as_buffer` member.
|
||||
|
||||
* :c:func:`PyIndex_Check` is now always declared as an opaque function to hide
|
||||
implementation details: removed the ``PyIndex_Check()`` macro. The macro accessed
|
||||
directly the :c:member:`PyTypeObject.tp_as_number` member.
|
||||
|
||||
(See :issue:`40170` for more details.)
|
||||
|
||||
Removed
|
||||
-------
|
||||
|
||||
* Exclude ``PyFPE_START_PROTECT()`` and ``PyFPE_END_PROTECT()`` macros of
|
||||
* Excluded ``PyFPE_START_PROTECT()`` and ``PyFPE_END_PROTECT()`` macros of
|
||||
``pyfpe.h`` from the limited C API.
|
||||
(Contributed by Victor Stinner in :issue:`38835`.)
|
||||
|
||||
|
|
@ -1158,7 +1382,7 @@ Removed
|
|||
|
||||
* Changes in the limited C API (if ``Py_LIMITED_API`` macro is defined):
|
||||
|
||||
* Exclude the following functions from the limited C API:
|
||||
* Excluded the following functions from the limited C API:
|
||||
|
||||
* ``PyThreadState_DeleteCurrent()``
|
||||
(Contributed by Joannah Nanjekye in :issue:`37878`.)
|
||||
|
|
@ -1175,7 +1399,7 @@ Removed
|
|||
* ``Py_TRASHCAN_SAFE_BEGIN``
|
||||
* ``Py_TRASHCAN_SAFE_END``
|
||||
|
||||
* Move following functions and definitions to the internal C API:
|
||||
* Moved following functions and definitions to the internal C API:
|
||||
|
||||
* ``_PyDebug_PrintTotalRefs()``
|
||||
* ``_Py_PrintReferences()``
|
||||
|
|
@ -1185,12 +1409,12 @@ Removed
|
|||
|
||||
(Contributed by Victor Stinner in :issue:`38644` and :issue:`39542`.)
|
||||
|
||||
* Remove ``_PyRuntime.getframe`` hook and remove ``_PyThreadState_GetFrame``
|
||||
* Removed ``_PyRuntime.getframe`` hook and removed ``_PyThreadState_GetFrame``
|
||||
macro which was an alias to ``_PyRuntime.getframe``. They were only exposed
|
||||
by the internal C API. Remove also ``PyThreadFrameGetter`` type.
|
||||
by the internal C API. Removed also ``PyThreadFrameGetter`` type.
|
||||
(Contributed by Victor Stinner in :issue:`39946`.)
|
||||
|
||||
* Remove the following functions from the C API. Call :c:func:`PyGC_Collect`
|
||||
* Removed the following functions from the C API. Call :c:func:`PyGC_Collect`
|
||||
explicitly to clear all free lists.
|
||||
(Contributed by Inada Naoki and Victor Stinner in :issue:`37340`,
|
||||
:issue:`38896` and :issue:`40428`.)
|
||||
|
|
@ -1209,10 +1433,20 @@ Removed
|
|||
* ``PyUnicode_ClearFreeList()``: the Unicode free list has been removed in
|
||||
Python 3.3.
|
||||
|
||||
* Remove ``_PyUnicode_ClearStaticStrings()`` function.
|
||||
* Removed ``_PyUnicode_ClearStaticStrings()`` function.
|
||||
(Contributed by Victor Stinner in :issue:`39465`.)
|
||||
|
||||
* Remove ``Py_UNICODE_MATCH``. It has been deprecated by :pep:`393`, and
|
||||
* Removed ``Py_UNICODE_MATCH``. It has been deprecated by :pep:`393`, and
|
||||
broken since Python 3.3. The :c:func:`PyUnicode_Tailmatch` function can be
|
||||
used instead.
|
||||
(Contributed by Inada Naoki in :issue:`36346`.)
|
||||
|
||||
* Cleaned header files of interfaces defined but with no implementation.
|
||||
The public API symbols being removed are:
|
||||
``_PyBytes_InsertThousandsGroupingLocale``,
|
||||
``_PyBytes_InsertThousandsGrouping``, ``_Py_InitializeFromArgs``,
|
||||
``_Py_InitializeFromWideArgs``, ``_PyFloat_Repr``, ``_PyFloat_Digits``,
|
||||
``_PyFloat_DigitsInit``, ``PyFrame_ExtendStack``, ``_PyAIterWrapper_Type``,
|
||||
``PyNullImporter_Type``, ``PyCmpWrapper_Type``, ``PySortWrapper_Type``,
|
||||
``PyNoArgsFunction``.
|
||||
(Contributed by Pablo Galindo Salgado in :issue:`39372`.)
|
||||
|
|
|
|||
Loading…
Reference in New Issue