What's New In Python 3.11
*************************

Release:
   3.11.0a0

Date:
   czerwca 17, 2021

This article explains the new features in Python 3.11, compared to
3.10.

For full details, see the changelog.

Informacja:

  Prerelease users should be aware that this document is currently in
  draft form. It will be updated substantially as Python 3.11 moves
  towards release, so it's worth checking back even after reading
  earlier versions.


Summary -- Release highlights
=============================


New Features
============


Other Language Changes
======================


New Modules
===========

* None yet.


Improved Modules
================


fractions
---------

Support **PEP 515**-style initialization of "Fraction" from string.
(Contributed by Sergey B Kirpichev in bpo-44258.)


math
----

* Add "math.cbrt()": return the cube root of x. (Contributed by Ajith
  Ramachandran in bpo-44357.)

* The behaviour of two "math.pow()" corner cases was changed, for
  consistency with the IEEE 754 specification. The operations
  "math.pow(0.0, -math.inf)" and "math.pow(-0.0, -math.inf)" now
  return "inf". Previously they raised "ValueError". (Contributed by
  Mark Dickinson in bpo-44339.)


Removed
=======

* "smtpd.MailmanProxy" is now removed as it is unusable without an
  external module, "mailman". (Contributed by Dong-hee Na in
  bpo-35800.)


Optimizations
=============

* Compiler now optimizes simple C-style formatting with literal format
  containing only format codes "%s", "%r" and "%a" and makes it as
  fast as corresponding f-string expression. (Contributed by Serhiy
  Storchaka in bpo-28307.)

* "Zero-cost" exceptions are implemented. The cost of "try" statements
  is almost eliminated when no exception is raised. (Contributed by
  Mark Shannon in bpo-40222.)

* Method calls with keywords are now faster due to bytecode changes
  which avoid creating bound method instances. Previously, this
  optimization was applied only to method calls with purely positional
  arguments. (Contributed by Ken Jin and Mark Shannon in bpo-26110,
  based on ideas implemented in PyPy.)


CPython bytecode changes
========================

* Added a new "CALL_METHOD_KW" opcode.  Calls a method in a similar
  fashion as "CALL_METHOD", but also supports keyword arguments.
  Works in tandem with "LOAD_METHOD".


Build Changes
=============


Deprecated
==========


Removed
=======


Porting to Python 3.11
======================

This section lists previously described changes and other bugfixes
that may require changes to your code.


C API Changes
=============


New Features
------------


Porting to Python 3.11
----------------------

* The "PyType_Ready()" function now raises an error if a type is
  defined with the "Py_TPFLAGS_HAVE_GC" flag set but has no traverse
  function ("PyTypeObject.tp_traverse"). (Contributed by Victor
  Stinner in bpo-44263.)


Deprecated
----------


Removed
-------

* "PyFrame_BlockSetup()" and "PyFrame_BlockPop()" have been removed.
  (Contributed by Mark Shannon in bpo-40222.)

* Deprecate the following functions to configure the Python
  initialization:

  * "PySys_AddWarnOptionUnicode()"

  * "PySys_AddWarnOption()"

  * "PySys_AddXOption()"

  * "PySys_HasWarnOptions()"

  * "Py_SetPath()"

  * "Py_SetProgramName()"

  * "Py_SetPythonHome()"

  * "Py_SetStandardStreamEncoding()"

  * "_Py_SetProgramFullPath()"

  Use the new "PyConfig" API of the Python Initialization
  Configuration instead (**PEP 587**). (Contributed by Victor Stinner
  in bpo-44113.)

* The following deprecated functions and methods are removed in the
  "gettext" module: "lgettext()", "ldgettext()", "lngettext()" and
  "ldngettext()".

  Function "bind_textdomain_codeset()", methods "output_charset()" and
  "set_output_charset()", and the *codeset* parameter of functions
  "translation()" and "install()" are also removed, since they are
  only used for the "l*gettext()" functions. (Contributed by Dong-hee
  Na and Serhiy Storchaka in bpo-44235.)
