Python 3.12 有什麼新功能¶
- 編輯者:
Adam Turner
本文介紹了 Python 3.12 與 3.11 相比多了哪些新功能。 Python 3.12 於 2023 年 10 月 2 日發布。完整詳情請見 changelog。
也參考
PEP 693 -- Python 3.12 發佈時程
發布重點摘要¶
Python 3.12 is a stable release of the Python programming language,
with a mix of changes to the language and the standard library.
The library changes focus on cleaning up deprecated APIs, usability, and correctness.
Of note, the distutils
package has been removed from the standard library.
Filesystem support in os
and pathlib
has seen a number of improvements,
and several modules have better performance.
The language changes focus on usability,
as f-strings have had many limitations removed
and 'Did you mean ...' suggestions continue to improve.
The new type parameter syntax
and type
statement improve ergonomics for using generic types and type aliases with static type checkers.
This article doesn't attempt to provide a complete specification of all new features, but instead gives a convenient overview. For full details, you should refer to the documentation, such as the Library Reference and Language Reference. If you want to understand the complete implementation and design rationale for a change, refer to the PEP for a particular new feature; but note that PEPs usually are not kept up-to-date once a feature has been fully implemented.
新增語法特性:
新增語法特性:
直譯器改進:
PEP 669, low impact monitoring
Improved 'Did you mean ...' suggestions for
NameError
,ImportError
, andSyntaxError
exceptions
Python 資料模型改進:
PEP 688, using the buffer protocol from Python
標準函式庫中的顯著改進
pathlib.Path
類別現在支援子類別化The
os
module received several improvements for Windows supportisinstance()
checks againstruntime-checkable protocols
enjoy a speed up of between two and 20 timesasyncio
套件進行了許多效能改進,一些基準測試顯示速度提高了 75%。Due to the changes in PEP 701, producing tokens via the
tokenize
module is up to 64% faster.
安全性改進:
Replace the builtin
hashlib
implementations of SHA1, SHA3, SHA2-384, SHA2-512, and MD5 with formally verified code from the HACL* project. These builtin implementations remain as fallbacks that are only used when OpenSSL does not provide them.
C API 改進:
CPython 實作改進:
PEP 709, comprehension inlining
CPython support for the Linux
perf
profilerImplement stack overflow protection on supported platforms
新增型別特性:
重要的棄用、刪除或限制:
PEP 623: Remove
wstr
from Unicode objects in Python's C API, reducing the size of everystr
object by at least 8 bytes.PEP 632: Remove the
distutils
package. See the migration guide for advice replacing the APIs it provided. The third-party Setuptools package continues to providedistutils
, if you still require it in Python 3.12 and beyond.gh-95299: Do not pre-install
setuptools
in virtual environments created withvenv
. This means thatdistutils
,setuptools
,pkg_resources
, andeasy_install
will no longer available by default; to access these runpip install setuptools
in the activated virtual environment.asynchat
、asyncore
和imp
模組以及幾個unittest.TestCase
的方法別名已被刪除。
新增功能¶
PEP 695:型別參數語法¶
Generic classes and functions under PEP 484 were declared using a verbose syntax that left the scope of type parameters unclear and required explicit declarations of variance.
PEP 695 introduces a new, more compact and explicit way to create generic classes and functions:
def max[T](args: Iterable[T]) -> T:
...
class list[T]:
def __getitem__(self, index: int, /) -> T:
...
def append(self, element: T) -> None:
...
In addition, the PEP introduces a new way to declare type aliases
using the type
statement, which creates an instance of
TypeAliasType
:
type Point = tuple[float, float]
型別別名也可以是泛型:
type Point[T] = tuple[T, T]
The new syntax allows declaring TypeVarTuple
and ParamSpec
parameters, as well as TypeVar
parameters with bounds or constraints:
type IntFunc[**P] = Callable[P, int] # ParamSpec
type LabeledTuple[*Ts] = tuple[str, *Ts] # TypeVarTuple
type HashableSequence[T: Hashable] = Sequence[T] # TypeVar with bound
type IntOrStrSequence[T: (int, str)] = Sequence[T] # TypeVar with constraints
The value of type aliases and the bound and constraints of type variables created through this syntax are evaluated only on demand (see lazy evaluation). This means type aliases are able to refer to other types defined later in the file.
Type parameters declared through a type parameter list are visible within the scope of the declaration and any nested scopes, but not in the outer scope. For example, they can be used in the type annotations for the methods of a generic class or in the class body. However, they cannot be used in the module scope after the class is defined. See Type parameter lists for a detailed description of the runtime semantics of type parameters.
In order to support these scoping semantics, a new kind of scope is introduced, the annotation scope. Annotation scopes behave for the most part like function scopes, but interact differently with enclosing class scopes. In Python 3.13, annotations will also be evaluated in annotation scopes.
詳情請見 PEP 695。
(PEP written by Eric Traut. Implementation by Jelle Zijlstra, Eric Traut, and others in gh-103764.)
PEP 701: Syntactic formalization of f-strings¶
PEP 701 lifts some restrictions on the usage of f-strings. Expression components inside f-strings can now be any valid Python expression, including strings reusing the same quote as the containing f-string, multi-line expressions, comments, backslashes, and unicode escape sequences. Let's cover these in detail:
Quote reuse: in Python 3.11, reusing the same quotes as the enclosing f-string raises a
SyntaxError
, forcing the user to either use other available quotes (like using double quotes or triple quotes if the f-string uses single quotes). In Python 3.12, you can now do things like this:>>> songs = ['Take me back to Eden', 'Alkaline', 'Ascensionism'] >>> f"This is the playlist: {", ".join(songs)}" 'This is the playlist: Take me back to Eden, Alkaline, Ascensionism'
Note that before this change there was no explicit limit in how f-strings can be nested, but the fact that string quotes cannot be reused inside the expression component of f-strings made it impossible to nest f-strings arbitrarily. In fact, this is the most nested f-string that could be written:
>>> f"""{f'''{f'{f"{1+1}"}'}'''}""" '2'
As now f-strings can contain any valid Python expression inside expression components, it is now possible to nest f-strings arbitrarily:
>>> f"{f"{f"{f"{f"{f"{1+1}"}"}"}"}"}" '2'
Multi-line expressions and comments: In Python 3.11, f-string expressions must be defined in a single line, even if the expression within the f-string could normally span multiple lines (like literal lists being defined over multiple lines), making them harder to read. In Python 3.12 you can now define f-strings spanning multiple lines, and add inline comments:
>>> f"This is the playlist: {", ".join([ ... 'Take me back to Eden', # My, my, those eyes like fire ... 'Alkaline', # Not acid nor alkaline ... 'Ascensionism' # Take to the broken skies at last ... ])}" 'This is the playlist: Take me back to Eden, Alkaline, Ascensionism'
Backslashes and unicode characters: before Python 3.12 f-string expressions couldn't contain any
\
character. This also affected unicode escape sequences (such as\N{snowman}
) as these contain the\N
part that previously could not be part of expression components of f-strings. Now, you can define expressions like this:>>> print(f"This is the playlist: {"\n".join(songs)}") This is the playlist: Take me back to Eden Alkaline Ascensionism >>> print(f"This is the playlist: {"\N{BLACK HEART SUIT}".join(songs)}") This is the playlist: Take me back to Eden♥Alkaline♥Ascensionism
詳情請見 PEP 701。
As a positive side-effect of how this feature has been implemented (by parsing f-strings
with the PEG parser), now error messages for f-strings are more precise
and include the exact location of the error. For example, in Python 3.11, the following
f-string raises a SyntaxError
:
>>> my_string = f"{x z y}" + f"{1 + 1}"
File "<stdin>", line 1
(x z y)
^^^
SyntaxError: f-string: invalid syntax. Perhaps you forgot a comma?
but the error message doesn't include the exact location of the error within the line and also has the expression artificially surrounded by parentheses. In Python 3.12, as f-strings are parsed with the PEG parser, error messages can be more precise and show the entire line:
>>> my_string = f"{x z y}" + f"{1 + 1}"
File "<stdin>", line 1
my_string = f"{x z y}" + f"{1 + 1}"
^^^
SyntaxError: invalid syntax. Perhaps you forgot a comma?
(Contributed by Pablo Galindo, Batuhan Taskaya, Lysandros Nikolaou, Cristián Maureira-Fredes and Marta Gómez in gh-102856. PEP written by Pablo Galindo, Batuhan Taskaya, Lysandros Nikolaou and Marta Gómez).
PEP 684: A Per-Interpreter GIL¶
PEP 684 introduces a per-interpreter GIL, so that sub-interpreters may now be created with a unique GIL per interpreter. This allows Python programs to take full advantage of multiple CPU cores. This is currently only available through the C-API, though a Python API is anticipated for 3.13.
Use the new Py_NewInterpreterFromConfig()
function to
create an interpreter with its own GIL:
PyInterpreterConfig config = {
.check_multi_interp_extensions = 1,
.gil = PyInterpreterConfig_OWN_GIL,
};
PyThreadState *tstate = NULL;
PyStatus status = Py_NewInterpreterFromConfig(&tstate, &config);
if (PyStatus_Exception(status)) {
return -1;
}
/* The new interpreter is now active in the current thread. */
For further examples how to use the C-API for sub-interpreters with a
per-interpreter GIL, see Modules/_xxsubinterpretersmodule.c
.
(由 Eric Snow 於 gh-104210 等貢獻。)
PEP 669: Low impact monitoring for CPython¶
PEP 669 defines a new API
for profilers,
debuggers, and other tools to monitor events in CPython.
It covers a wide range of events, including calls,
returns, lines, exceptions, jumps, and more.
This means that you only pay for what you use, providing support
for near-zero overhead debuggers and coverage tools.
See sys.monitoring
for details.
(由 Mark Shannon 於 gh-103082 中貢獻。)
PEP 688: Making the buffer protocol accessible in Python¶
PEP 688 introduces a way to use the buffer protocol
from Python code. Classes that implement the __buffer__()
method
are now usable as buffer types.
The new collections.abc.Buffer
ABC provides a standard
way to represent buffer objects, for example in type annotations.
The new inspect.BufferFlags
enum represents the flags that
can be used to customize buffer creation.
(Contributed by Jelle Zijlstra in gh-102500.)
PEP 709: Comprehension inlining¶
Dictionary, list, and set comprehensions are now inlined, rather than creating a new single-use function object for each execution of the comprehension. This speeds up execution of a comprehension by up to two times. See PEP 709 for further details.
Comprehension iteration variables remain isolated and don't overwrite a variable of the same name in the outer scope, nor are they visible after the comprehension. Inlining does result in a few visible behavior changes:
There is no longer a separate frame for the comprehension in tracebacks, and tracing/profiling no longer shows the comprehension as a function call.
The
symtable
module will no longer produce child symbol tables for each comprehension; instead, the comprehension's locals will be included in the parent function's symbol table.Calling
locals()
inside a comprehension now includes variables from outside the comprehension, and no longer includes the synthetic.0
variable for the comprehension "argument".A comprehension iterating directly over
locals()
(e.g.[k for k in locals()]
) may see "RuntimeError: dictionary changed size during iteration" when run under tracing (e.g. code coverage measurement). This is the same behavior already seen in e.g.for k in locals():
. To avoid the error, first create a list of keys to iterate over:keys = list(locals()); [k for k in keys]
.
(由 Carl Meyer 和 Vladimir Matveev 於 PEP 709 中貢獻。)
Improved Error Messages¶
Modules from the standard library are now potentially suggested as part of the error messages displayed by the interpreter when a
NameError
is raised to the top level. (Contributed by Pablo Galindo in gh-98254.)>>> sys.version_info Traceback (most recent call last): File "<stdin>", line 1, in <module> NameError: name 'sys' is not defined. Did you forget to import 'sys'?
Improve the error suggestion for
NameError
exceptions for instances. Now if aNameError
is raised in a method and the instance has an attribute that's exactly equal to the name in the exception, the suggestion will includeself.<NAME>
instead of the closest match in the method scope. (Contributed by Pablo Galindo in gh-99139.)>>> class A: ... def __init__(self): ... self.blech = 1 ... ... def foo(self): ... somethin = blech ... >>> A().foo() Traceback (most recent call last): File "<stdin>", line 1 somethin = blech ^^^^^ NameError: name 'blech' is not defined. Did you mean: 'self.blech'?
Improve the
SyntaxError
error message when the user typesimport x from y
instead offrom y import x
. (Contributed by Pablo Galindo in gh-98931.)>>> import a.y.z from b.y.z Traceback (most recent call last): File "<stdin>", line 1 import a.y.z from b.y.z ^^^^^^^^^^^^^^^^^^^^^^^ SyntaxError: Did you mean to use 'from ... import ...' instead?
ImportError
exceptions raised from failedfrom <module> import <name>
statements now include suggestions for the value of<name>
based on the available names in<module>
. (Contributed by Pablo Galindo in gh-91058.)>>> from collections import chainmap Traceback (most recent call last): File "<stdin>", line 1, in <module> ImportError: cannot import name 'chainmap' from 'collections'. Did you mean: 'ChainMap'?
其他語言更動¶
The parser now raises
SyntaxError
when parsing source code containing null bytes. (Contributed by Pablo Galindo in gh-96670.)A backslash-character pair that is not a valid escape sequence now generates a
SyntaxWarning
, instead ofDeprecationWarning
. For example,re.compile("\d+\.\d+")
now emits aSyntaxWarning
("\d"
is an invalid escape sequence, use raw strings for regular expression:re.compile(r"\d+\.\d+")
). In a future Python version,SyntaxError
will eventually be raised, instead ofSyntaxWarning
. (Contributed by Victor Stinner in gh-98401.)Octal escapes with value larger than
0o377
(ex:"\477"
), deprecated in Python 3.11, now produce aSyntaxWarning
, instead ofDeprecationWarning
. In a future Python version they will be eventually aSyntaxError
. (Contributed by Victor Stinner in gh-98401.)Variables used in the target part of comprehensions that are not stored to can now be used in assignment expressions (
:=
). For example, in[(b := 1) for a, b.prop in some_iter]
, the assignment tob
is now allowed. Note that assigning to variables stored to in the target part of comprehensions (likea
) is still disallowed, as per PEP 572. (Contributed by Nikita Sobolev in gh-100581.)Exceptions raised in a class or type's
__set_name__
method are no longer wrapped by aRuntimeError
. Context information is added to the exception as a PEP 678 note. (Contributed by Irit Katriel in gh-77757.)When a
try-except*
construct handles the entireExceptionGroup
and raises one other exception, that exception is no longer wrapped in anExceptionGroup
. Also changed in version 3.11.4. (Contributed by Irit Katriel in gh-103590.)The Garbage Collector now runs only on the eval breaker mechanism of the Python bytecode evaluation loop instead of object allocations. The GC can also run when
PyErr_CheckSignals()
is called so C extensions that need to run for a long time without executing any Python code also have a chance to execute the GC periodically. (Contributed by Pablo Galindo in gh-97922.)All builtin and extension callables expecting boolean parameters now accept arguments of any type instead of just
bool
andint
. (Contributed by Serhiy Storchaka in gh-60203.)memoryview
now supports the half-float type (the "e" format code). (Contributed by Donghee Na and Antoine Pitrou in gh-90751.)slice
objects are now hashable, allowing them to be used as dict keys and set items. (Contributed by Will Bradshaw, Furkan Onder, and Raymond Hettinger in gh-101264.)sum()
now uses Neumaier summation to improve accuracy and commutativity when summing floats or mixed ints and floats. (Contributed by Raymond Hettinger in gh-100425.)ast.parse()
now raisesSyntaxError
instead ofValueError
when parsing source code containing null bytes. (Contributed by Pablo Galindo in gh-96670.)The extraction methods in
tarfile
, andshutil.unpack_archive()
, have a new a filter argument that allows limiting tar features than may be surprising or dangerous, such as creating files outside the destination directory. See tarfile extraction filters for details. In Python 3.14, the default will switch to'data'
. (Contributed by Petr Viktorin in PEP 706.)types.MappingProxyType
instances are now hashable if the underlying mapping is hashable. (Contributed by Serhiy Storchaka in gh-87995.)Add support for the perf profiler through the new environment variable
PYTHONPERFSUPPORT
and command-line option-X perf
, as well as the newsys.activate_stack_trampoline()
,sys.deactivate_stack_trampoline()
, andsys.is_stack_trampoline_active()
functions. (Design by Pablo Galindo. Contributed by Pablo Galindo and Christian Heimes with contributions from Gregory P. Smith [Google] and Mark Shannon in gh-96123.)
新增模組¶
None.
改進的模組¶
array¶
The
array.array
class now supports subscripting, making it a generic type. (Contributed by Jelle Zijlstra in gh-98658.)
asyncio¶
The performance of writing to sockets in
asyncio
has been significantly improved.asyncio
now avoids unnecessary copying when writing to sockets and usessendmsg()
if the platform supports it. (Contributed by Kumar Aditya in gh-91166.)Add
asyncio.eager_task_factory()
andasyncio.create_eager_task_factory()
functions to allow opting an event loop in to eager task execution, making some use-cases 2x to 5x faster. (Contributed by Jacob Bower & Itamar Oren in gh-102853, gh-104140, and gh-104138)On Linux,
asyncio
usesasyncio.PidfdChildWatcher
by default ifos.pidfd_open()
is available and functional instead ofasyncio.ThreadedChildWatcher
. (Contributed by Kumar Aditya in gh-98024.)The event loop now uses the best available child watcher for each platform (
asyncio.PidfdChildWatcher
if supported andasyncio.ThreadedChildWatcher
otherwise), so manually configuring a child watcher is not recommended. (Contributed by Kumar Aditya in gh-94597.)Add loop_factory parameter to
asyncio.run()
to allow specifying a custom event loop factory. (Contributed by Kumar Aditya in gh-99388.)Add C implementation of
asyncio.current_task()
for 4x-6x speedup. (Contributed by Itamar Oren and Pranav Thulasiram Bhat in gh-100344.)asyncio.iscoroutine()
now returnsFalse
for generators asasyncio
does not support legacy generator-based coroutines. (Contributed by Kumar Aditya in gh-102748.)asyncio.wait()
andasyncio.as_completed()
now accepts generators yielding tasks. (Contributed by Kumar Aditya in gh-78530.)
calendar¶
Add enums
calendar.Month
andcalendar.Day
defining months of the year and days of the week. (Contributed by Prince Roshan in gh-103636.)
csv¶
Add
csv.QUOTE_NOTNULL
andcsv.QUOTE_STRINGS
flags to provide finer grained control ofNone
and empty strings byreader
andwriter
objects.
dis¶
Pseudo instruction opcodes (which are used by the compiler but do not appear in executable bytecode) are now exposed in the
dis
module.HAVE_ARGUMENT
is still relevant to real opcodes, but it is not useful for pseudo instructions. Use the newdis.hasarg
collection instead. (Contributed by Irit Katriel in gh-94216.)Add the
dis.hasexc
collection to signify instructions that set an exception handler. (Contributed by Irit Katriel in gh-94216.)
fractions¶
Objects of type
fractions.Fraction
now support float-style formatting. (Contributed by Mark Dickinson in gh-100161.)
importlib.resources¶
importlib.resources.as_file()
now supports resource directories. (Contributed by Jason R. Coombs in gh-97930.)Rename first parameter of
importlib.resources.files()
to anchor. (Contributed by Jason R. Coombs in gh-100598.)
inspect¶
Add
inspect.markcoroutinefunction()
to mark sync functions that return a coroutine for use withinspect.iscoroutinefunction()
. (Contributed by Carlton Gibson in gh-99247.)Add
inspect.getasyncgenstate()
andinspect.getasyncgenlocals()
for determining the current state of asynchronous generators. (Contributed by Thomas Krennwallner in gh-79940.)The performance of
inspect.getattr_static()
has been considerably improved. Most calls to the function should be at least 2x faster than they were in Python 3.11. (Contributed by Alex Waygood in gh-103193.)
itertools¶
Add
itertools.batched()
for collecting into even-sized tuples where the last batch may be shorter than the rest. (Contributed by Raymond Hettinger in gh-98363.)
math¶
新增
math.sumprod()
以計算乘積總和。(由 Raymond Hettinger 於 gh-100485 中貢獻。)Extend
math.nextafter()
to include a steps argument for moving up or down multiple steps at a time. (Contributed by Matthias Goergens, Mark Dickinson, and Raymond Hettinger in gh-94906.)
os¶
Add
os.PIDFD_NONBLOCK
to open a file descriptor for a process withos.pidfd_open()
in non-blocking mode. (Contributed by Kumar Aditya in gh-93312.)os.DirEntry
now includes anos.DirEntry.is_junction()
method to check if the entry is a junction. (Contributed by Charles Machalow in gh-99547.)Add
os.listdrives()
,os.listvolumes()
andos.listmounts()
functions on Windows for enumerating drives, volumes and mount points. (Contributed by Steve Dower in gh-102519.)os.stat()
andos.lstat()
are now more accurate on Windows. Thest_birthtime
field will now be filled with the creation time of the file, andst_ctime
is deprecated but still contains the creation time (but in the future will return the last metadata change, for consistency with other platforms).st_dev
may be up to 64 bits andst_ino
up to 128 bits depending on your file system, andst_rdev
is always set to zero rather than incorrect values. Both functions may be significantly faster on newer releases of Windows. (Contributed by Steve Dower in gh-99726.)
os.path¶
Add
os.path.isjunction()
to check if a given path is a junction. (Contributed by Charles Machalow in gh-99547.)Add
os.path.splitroot()
to split a path into a triad(drive, root, tail)
. (Contributed by Barney Gale in gh-101000.)
pathlib¶
Add support for subclassing
pathlib.PurePath
andpathlib.Path
, plus their Posix- and Windows-specific variants. Subclasses may override thepathlib.PurePath.with_segments()
method to pass information between path instances.Add
pathlib.Path.walk()
for walking the directory trees and generating all file or directory names within them, similar toos.walk()
. (Contributed by Stanislav Zmiev in gh-90385.)Add walk_up optional parameter to
pathlib.PurePath.relative_to()
to allow the insertion of..
entries in the result; this behavior is more consistent withos.path.relpath()
. (Contributed by Domenico Ragusa in gh-84538.)Add
pathlib.Path.is_junction()
as a proxy toos.path.isjunction()
. (Contributed by Charles Machalow in gh-99547.)Add case_sensitive optional parameter to
pathlib.Path.glob()
,pathlib.Path.rglob()
andpathlib.PurePath.match()
for matching the path's case sensitivity, allowing for more precise control over the matching process.
pdb¶
Add convenience variables to hold values temporarily for debug session and provide quick access to values like the current frame or the return value. (Contributed by Tian Gao in gh-103693.)
random¶
新增
random.binomialvariate()
。(由 Raymond Hettinger 於 gh-81620 中貢獻。)將預設值
lambd=1.0
加入至random.expovariate()
中。(由 Raymond Hettinger 在 gh-100234 中貢獻。)
shutil¶
shutil.make_archive()
now passes the root_dir argument to custom archivers which support it. In this case it no longer temporarily changes the current working directory of the process to root_dir to perform archiving. (Contributed by Serhiy Storchaka in gh-74696.)shutil.rmtree()
now accepts a new argument onexc which is an error handler like onerror but which expects an exception instance rather than a (typ, val, tb) triplet. onerror is deprecated. (Contributed by Irit Katriel in gh-102828.)shutil.which()
now consults the PATHEXT environment variable to find matches within PATH on Windows even when the given cmd includes a directory component. (Contributed by Charles Machalow in gh-103179.)shutil.which()
will callNeedCurrentDirectoryForExePathW
when querying for executables on Windows to determine if the current working directory should be prepended to the search path. (Contributed by Charles Machalow in gh-103179.)shutil.which()
will return a path matching the cmd with a component fromPATHEXT
prior to a direct match elsewhere in the search path on Windows. (Contributed by Charles Machalow in gh-103179.)
sqlite3¶
Add the
sqlite3.Connection.autocommit
attribute tosqlite3.Connection
and the autocommit parameter tosqlite3.connect()
to control PEP 249-compliant transaction handling. (Contributed by Erlend E. Aasland in gh-83638.)Add entrypoint keyword-only parameter to
sqlite3.Connection.load_extension()
, for overriding the SQLite extension entry point. (Contributed by Erlend E. Aasland in gh-103015.)Add
sqlite3.Connection.getconfig()
andsqlite3.Connection.setconfig()
tosqlite3.Connection
to make configuration changes to a database connection. (Contributed by Erlend E. Aasland in gh-103489.)
statistics¶
Extend
statistics.correlation()
to include as aranked
method for computing the Spearman correlation of ranked data. (Contributed by Raymond Hettinger in gh-95861.)
sys¶
Add the
sys.monitoring
namespace to expose the new PEP 669 monitoring API. (Contributed by Mark Shannon in gh-103082.)Add
sys.activate_stack_trampoline()
andsys.deactivate_stack_trampoline()
for activating and deactivating stack profiler trampolines, andsys.is_stack_trampoline_active()
for querying if stack profiler trampolines are active. (Contributed by Pablo Galindo and Christian Heimes with contributions from Gregory P. Smith [Google] and Mark Shannon in gh-96123.)Add
sys.last_exc
which holds the last unhandled exception that was raised (for post-mortem debugging use cases). Deprecate the three fields that have the same information in its legacy form:sys.last_type
,sys.last_value
andsys.last_traceback
. (Contributed by Irit Katriel in gh-102778.)sys._current_exceptions()
now returns a mapping from thread-id to an exception instance, rather than to a(typ, exc, tb)
tuple. (Contributed by Irit Katriel in gh-103176.)sys.setrecursionlimit()
andsys.getrecursionlimit()
. The recursion limit now applies only to Python code. Builtin functions do not use the recursion limit, but are protected by a different mechanism that prevents recursion from causing a virtual machine crash.
tempfile¶
tempfile.NamedTemporaryFile
函式新增了一個選擇性參數 delete_on_close (由 Evgeny Zorin 於 gh-58451 中貢獻。)tempfile.mkdtemp()
現在總是會傳回絕對路徑,即使提供給 dir 參數的引數是相對路徑。
threading¶
Add
threading.settrace_all_threads()
andthreading.setprofile_all_threads()
that allow to set tracing and profiling functions in all running threads in addition to the calling one. (Contributed by Pablo Galindo in gh-93503.)
tkinter¶
tkinter.Canvas.coords()
now flattens its arguments. It now accepts not only coordinates as separate arguments (x1, y1, x2, y2, ...
) and a sequence of coordinates ([x1, y1, x2, y2, ...]
), but also coordinates grouped in pairs ((x1, y1), (x2, y2), ...
and[(x1, y1), (x2, y2), ...]
), likecreate_*()
methods. (Contributed by Serhiy Storchaka in gh-94473.)
tokenize¶
The
tokenize
module includes the changes introduced in PEP 701. (Contributed by Marta Gómez Macías and Pablo Galindo in gh-102856.) See 移植至 Python 3.12 for more information on the changes to thetokenize
module.
types¶
Add
types.get_original_bases()
to allow for further introspection of 使用者定義泛型型別 when subclassed. (Contributed by James Hilton-Balfe and Alex Waygood in gh-101827.)
typing¶
isinstance()
checks againstruntime-checkable protocols
now useinspect.getattr_static()
rather thanhasattr()
to lookup whether attributes exist. This means that descriptors and__getattr__()
methods are no longer unexpectedly evaluated duringisinstance()
checks against runtime-checkable protocols. However, it may also mean that some objects which used to be considered instances of a runtime-checkable protocol may no longer be considered instances of that protocol on Python 3.12+, and vice versa. Most users are unlikely to be affected by this change. (Contributed by Alex Waygood in gh-102433.)The members of a runtime-checkable protocol are now considered "frozen" at runtime as soon as the class has been created. Monkey-patching attributes onto a runtime-checkable protocol will still work, but will have no impact on
isinstance()
checks comparing objects to the protocol. For example:>>> from typing import Protocol, runtime_checkable >>> @runtime_checkable ... class HasX(Protocol): ... x = 1 ... >>> class Foo: ... ... >>> f = Foo() >>> isinstance(f, HasX) False >>> f.x = 1 >>> isinstance(f, HasX) True >>> HasX.y = 2 >>> isinstance(f, HasX) # unchanged, even though HasX now also has a "y" attribute True
This change was made in order to speed up
isinstance()
checks against runtime-checkable protocols.The performance profile of
isinstance()
checks againstruntime-checkable protocols
has changed significantly. Mostisinstance()
checks against protocols with only a few members should be at least 2x faster than in 3.11, and some may be 20x faster or more. However,isinstance()
checks against protocols with many members may be slower than in Python 3.11. (Contributed by Alex Waygood in gh-74690 and gh-103193.)All
typing.TypedDict
andtyping.NamedTuple
classes now have the__orig_bases__
attribute. (Contributed by Adrian Garcia Badaracco in gh-103699.)新增
frozen_default
參數至typing.dataclass_transform()
。(由 Erik De Bonte 於 gh-99957 中貢獻。)
unicodedata¶
The Unicode database has been updated to version 15.0.0. (Contributed by Benjamin Peterson in gh-96734).
unittest¶
新增 --durations
命令列選項,顯示 N 個最慢的測試案例:
python3 -m unittest --durations=3 lib.tests.test_threading
.....
Slowest test durations
----------------------------------------------------------------------
1.210s test_timeout (Lib.test.test_threading.BarrierTests)
1.003s test_default_timeout (Lib.test.test_threading.BarrierTests)
0.518s test_timeout (Lib.test.test_threading.EventTests)
(0.000 durations hidden. Use -v to show these durations.)
----------------------------------------------------------------------
Ran 158 tests in 9.869s
OK (skipped=3)
(由 Giampaolo Rodola 於 gh-48330 中貢獻。)
uuid¶
最佳化¶
Remove
wstr
andwstr_length
members from Unicode objects. It reduces object size by 8 or 16 bytes on 64bit platform. (PEP 623) (Contributed by Inada Naoki in gh-92536.)Add experimental support for using the BOLT binary optimizer in the build process, which improves performance by 1-5%. (Contributed by Kevin Modzelewski in gh-90536 and tuned by Donghee Na in gh-101525)
Speed up the regular expression substitution (functions
re.sub()
andre.subn()
and correspondingre.Pattern
methods) for replacement strings containing group references by 2--3 times. (Contributed by Serhiy Storchaka in gh-91524.)Speed up
asyncio.Task
creation by deferring expensive string formatting. (Contributed by Itamar Oren in gh-103793.)The
tokenize.tokenize()
andtokenize.generate_tokens()
functions are up to 64% faster as a side effect of the changes required to cover PEP 701 in thetokenize
module. (Contributed by Marta Gómez Macías and Pablo Galindo in gh-102856.)Speed up
super()
method calls and attribute loads via the newLOAD_SUPER_ATTR
instruction. (Contributed by Carl Meyer and Vladimir Matveev in gh-103497.)
CPython 位元組碼變更¶
Remove the
LOAD_METHOD
instruction. It has been merged intoLOAD_ATTR
.LOAD_ATTR
will now behave like the oldLOAD_METHOD
instruction if the low bit of its oparg is set. (Contributed by Ken Jin in gh-93429.)Remove the
JUMP_IF_FALSE_OR_POP
andJUMP_IF_TRUE_OR_POP
instructions. (Contributed by Irit Katriel in gh-102859.)Remove the
PRECALL
instruction. (Contributed by Mark Shannon in gh-92925.)Add the
BINARY_SLICE
andSTORE_SLICE
instructions. (Contributed by Mark Shannon in gh-94163.)Add the
CALL_INTRINSIC_1
instructions. (Contributed by Mark Shannon in gh-99005.)Add the
CALL_INTRINSIC_2
instruction. (Contributed by Irit Katriel in gh-101799.)Add the
CLEANUP_THROW
instruction. (Contributed by Brandt Bucher in gh-90997.)Add the
END_SEND
instruction. (Contributed by Mark Shannon in gh-103082.)Add the
LOAD_FAST_AND_CLEAR
instruction as part of the implementation of PEP 709. (Contributed by Carl Meyer in gh-101441.)Add the
LOAD_FAST_CHECK
instruction. (Contributed by Dennis Sweeney in gh-93143.)Add the
LOAD_FROM_DICT_OR_DEREF
,LOAD_FROM_DICT_OR_GLOBALS
, andLOAD_LOCALS
opcodes as part of the implementation of PEP 695. Remove theLOAD_CLASSDEREF
opcode, which can be replaced withLOAD_LOCALS
plusLOAD_FROM_DICT_OR_DEREF
. (Contributed by Jelle Zijlstra in gh-103764.)Add the
LOAD_SUPER_ATTR
instruction. (Contributed by Carl Meyer and Vladimir Matveev in gh-103497.)Add the
RETURN_CONST
instruction. (Contributed by Wenyang Wang in gh-101632.)
Demos and Tools¶
Remove the
Tools/demo/
directory which contained old demo scripts. A copy can be found in the old-demos project. (Contributed by Victor Stinner in gh-97681.)Remove outdated example scripts of the
Tools/scripts/
directory. A copy can be found in the old-demos project. (Contributed by Victor Stinner in gh-97669.)
已棄用¶
argparse
:argparse.BooleanOptionalAction
的 type、choices 和 metavar 參數已被棄用,將在 3.14 中移除。 (由 Nikita Sobolev 於 gh-92248 貢獻。)ast
: The followingast
features have been deprecated in documentation since Python 3.8, now cause aDeprecationWarning
to be emitted at runtime when they are accessed or used, and will be removed in Python 3.14:ast.Num
ast.Str
ast.Bytes
ast.NameConstant
ast.Ellipsis
請改用
ast.Constant
。(由 Serhiy Storchaka 於 gh-90953 貢獻。)-
The child watcher classes
asyncio.MultiLoopChildWatcher
,asyncio.FastChildWatcher
,asyncio.AbstractChildWatcher
andasyncio.SafeChildWatcher
are deprecated and will be removed in Python 3.14. (Contributed by Kumar Aditya in gh-94597.)asyncio.set_child_watcher()
、asyncio.get_child_watcher()
、asyncio.AbstractEventLoopPolicy.set_child_watcher()
和asyncio.AbstractEventLoopPolicy.get_child_watcher()
已被棄用並將在 Python 3.14 中移除。(由 Kumar Aditya 於 gh-94597 貢獻。)預設事件迴圈策略的
get_event_loop()
方法現在會在沒有設定目前事件迴圈且決定建立一個時發出DeprecationWarning
。 (由 Serhiy Storchaka 和 Guido van Rossum 於 gh-100160 貢獻。)
calendar
:calendar.January
和calendar.February
常數已被棄用並被calendar.JANUARY
和calendar.FEBRUARY
取代。 (由 Prince Roshan 於 gh-103636 貢獻。)collections.abc
: Deprecatedcollections.abc.ByteString
. PreferSequence
orcollections.abc.Buffer
. For use in typing, prefer a union, likebytes | bytearray
, orcollections.abc.Buffer
. (Contributed by Shantanu Jain in gh-91896.)datetime
:datetime.datetime
'sutcnow()
andutcfromtimestamp()
are deprecated and will be removed in a future version. Instead, use timezone-aware objects to represent datetimes in UTC: respectively, callnow()
andfromtimestamp()
with the tz parameter set todatetime.UTC
. (Contributed by Paul Ganssle in gh-103857.)email
:棄用email.utils.localtime()
中的 isdst 參數。(由 Alan Williams 於 gh-72346 中貢獻。)importlib.abc
:棄用下列類別,預定於 Python 3.14 中移除:importlib.abc.ResourceReader
importlib.abc.Traversable
importlib.abc.TraversableResources
請改用
importlib.resources.abc
類別:(由 Jason R. Coombs 和 Hugo van Kemenade 貢獻於 gh-93963。)
itertools
: Deprecate the support for copy, deepcopy, and pickle operations, which is undocumented, inefficient, historically buggy, and inconsistent. This will be removed in 3.14 for a significant reduction in code volume and maintenance burden. (Contributed by Raymond Hettinger in gh-101588.)multiprocessing
: In Python 3.14, the defaultmultiprocessing
start method will change to a safer one on Linux, BSDs, and other non-macOS POSIX platforms where'fork'
is currently the default (gh-84559). Adding a runtime warning about this was deemed too disruptive as the majority of code is not expected to care. Use theget_context()
orset_start_method()
APIs to explicitly specify when your code requires'fork'
. See contexts and start methods.pkgutil
:pkgutil.find_loader()
和pkgutil.get_loader()
已被棄用並將在 Python 3.14 中移除;請改用importlib.util.find_spec()
。(由 Nikita Sobolev 於 gh-97850 中貢獻。)pty
: The module has two undocumentedmaster_open()
andslave_open()
functions that have been deprecated since Python 2 but only gained a properDeprecationWarning
in 3.12. Remove them in 3.14. (Contributed by Soumendra Ganguly and Gregory P. Smith in gh-85984.)os
:The
st_ctime
fields return byos.stat()
andos.lstat()
on Windows are deprecated. In a future release, they will contain the last metadata change time, consistent with other platforms. For now, they still contain the creation time, which is also available in the newst_birthtime
field. (Contributed by Steve Dower in gh-99726.)On POSIX platforms,
os.fork()
can now raise aDeprecationWarning
when it can detect being called from a multithreaded process. There has always been a fundamental incompatibility with the POSIX platform when doing so. Even if such code appeared to work. We added the warning to raise awareness as issues encountered by code doing this are becoming more frequent. See theos.fork()
documentation for more details along with this discussion on fork being incompatible with threads for why we're now surfacing this longstanding platform compatibility problem to developers.
When this warning appears due to usage of
multiprocessing
orconcurrent.futures
the fix is to use a differentmultiprocessing
start method such as"spawn"
or"forkserver"
.shutil
:shutil.rmtree()
的 onerror 引數已被棄用,請改用 onexc。(由 Irit Katriel 於 gh-102828 中貢獻。)-
default adapters and converters are now deprecated. Instead, use the Adapter and converter recipes and tailor them to your needs. (Contributed by Erlend E. Aasland in gh-90016.)
In
execute()
,DeprecationWarning
is now emitted when named placeholders are used together with parameters supplied as a sequence instead of as adict
. Starting from Python 3.14, using named placeholders with parameters supplied as a sequence will raise aProgrammingError
. (Contributed by Erlend E. Aasland in gh-101698.)
sys
:sys.last_type
、sys.last_value
和sys.last_traceback
欄位已被棄用。請改用sys.last_exc
。(由 Irit Katriel 於 gh-102778 中貢獻。)tarfile
: Extracting tar archives without specifying filter is deprecated until Python 3.14, when'data'
filter will become the default. See Extraction filters for details.-
typing.Hashable
andtyping.Sized
, aliases forcollections.abc.Hashable
andcollections.abc.Sized
respectively, are deprecated. (gh-94309.)typing.ByteString
, deprecated since Python 3.9, now causes aDeprecationWarning
to be emitted when it is used. (Contributed by Alex Waygood in gh-91896.)
xml.etree.ElementTree
: The module now emitsDeprecationWarning
when testing the truth value of anxml.etree.ElementTree.Element
. Before, the Python implementation emittedFutureWarning
, and the C implementation emitted nothing. (Contributed by Jacob Walls in gh-83122.)The 3-arg signatures (type, value, traceback) of
coroutine throw()
,generator throw()
andasync generator throw()
are deprecated and may be removed in a future version of Python. Use the single-arg versions of these functions instead. (Contributed by Ofey Chan in gh-89874.)DeprecationWarning
is now raised when__package__
on a module differs from__spec__.parent
(previously it wasImportWarning
). (Contributed by Brett Cannon in gh-65961.)Setting
__package__
or__cached__
on a module is deprecated, and will cease to be set or taken into consideration by the import system in Python 3.14. (Contributed by Brett Cannon in gh-65961.)The bitwise inversion operator (
~
) on bool is deprecated. It will throw an error in Python 3.16. Usenot
for logical negation of bools instead. In the rare case that you really need the bitwise inversion of the underlyingint
, convert to int explicitly:~int(x)
. (Contributed by Tim Hoffmann in gh-103487.)自 3.10 起,於程式碼物件存取
co_lnotab
的功能已在 PEP 626 中被棄用,但只在 3.12 中於適時發出DeprecationWarning
。可能在 3.15 中移除。(由 Nikita Sobolev 於 gh-101866 貢獻。)
Python 3.13 中待移除的項目¶
模組(請見 PEP 594):
aifc
audioop
cgi
cgitb
chunk
crypt
imghdr
mailcap
msilib
nis
nntplib
ossaudiodev
pipes
sndhdr
spwd
sunau
telnetlib
uu
xdrlib
其他模組:
lib2to3
和 2to3 程式 (gh-84540)
API:
configparser.LegacyInterpolation
(gh-90765)locale.resetlocale()
(gh-90817)turtle.RawTurtle.settiltangle()
(gh-50096)unittest.findTestCases()
(gh-50096)unittest.getTestCaseNames()
(gh-50096)unittest.makeSuite()
(gh-50096)unittest.TestProgram.usageExit()
(gh-67048)webbrowser.MacOSX
(gh-86421)classmethod
描述器鏈接 (gh-89519)importlib.resources
的已棄用方法:contents()
is_resource()
open_binary()
open_text()
path()
read_binary()
read_text()
請改用
importlib.resources.files()
。請參閱 importlib-resources: Migrating from Legacy (gh-106531)
Python 3.14 中待移除的項目¶
argparse
:argparse.BooleanOptionalAction
的 type、choices 和 metavar 參數已被棄用,將在 3.14 中移除。 (由 Nikita Sobolev 於 gh-92248 貢獻。)ast
:自 Python 3.8 起,下列功能已在文件中被棄用,現在在存取或使用時會於 runtime 發出DeprecationWarning
,並將在 Python 3.14 中移除:ast.Num
ast.Str
ast.Bytes
ast.NameConstant
ast.Ellipsis
請改用
ast.Constant
。(由 Serhiy Storchaka 於 gh-90953 貢獻。)-
已棄用並將在 Python 3.14 中移除的 child watcher 類別:
MultiLoopChildWatcher
、FastChildWatcher
、AbstractChildWatcher
和SafeChildWatcher
。 (由 Kumar Aditya 於 gh-94597 貢獻。)asyncio.set_child_watcher()
、asyncio.get_child_watcher()
、asyncio.AbstractEventLoopPolicy.set_child_watcher()
和asyncio.AbstractEventLoopPolicy.get_child_watcher()
已被棄用並將在 Python 3.14 中移除。(由 Kumar Aditya 於 gh-94597 貢獻。)預設事件迴圈策略的
get_event_loop()
方法現在會在沒有設定目前事件迴圈且決定建立一個時發出DeprecationWarning
。 (由 Serhiy Storchaka 和 Guido van Rossum 於 gh-100160 貢獻。)
collections.abc
:已棄用ByteString
。請改用Sequence
或Buffer
。在 typing 中使用時,請改用聯集,如bytes | bytearray
,或collections.abc.Buffer
。(由 Shantanu Jain 於 gh-91896 貢獻。)email
:已棄用email.utils.localtime()
中的 isdst 參數。(由 Alan Williams 於 gh-72346 貢獻。)importlib.abc
的已棄用類別:importlib.abc.ResourceReader
importlib.abc.Traversable
importlib.abc.TraversableResources
請改用
importlib.resources.abc
類別:(由 Jason R. Coombs 和 Hugo van Kemenade 貢獻於 gh-93963。)
itertools
有不以文件記錄、效率低下、過去常有 bug 且不一致的 copy、deepcopy 和 pickle 操作支援。將在 3.14 中移除以大幅減少程式碼量和維護負擔。 (由 Raymond Hettinger 於 gh-101588 貢獻。)multiprocessing
:預設的啟動方法將在 Linux、BSD 和其他非 macOS POSIX 平台上更改為更安全的 方法,目前'fork'
是預設值 (gh-84559)。對此增加一個 runtime 警告被認為太過擾人,因為 大多數程式碼不會在意。請使用get_context()
或set_start_method()
API 來明確指定你的程式碼何時需要'fork'
。請參閱 Contexts and start methods。pathlib
:已棄用is_relative_to()
和relative_to()
:額外引數的傳遞已被棄用。pkgutil
:find_loader()
和get_loader()
現在會引發DeprecationWarning
;請改用importlib.util.find_spec()
。 (由 Nikita Sobolev 於 gh-97850 貢獻。)pty
:master_open()
:請用pty.openpty()
。slave_open()
:請用pty.openpty()
。
-
execute()
和executemany()
,如果使用 named placeholders 且 parameters 是序列而不是dict
。
typing
:自 Python 3.9 起已被棄用的ByteString
現在在使用時會發出DeprecationWarning
。urllib
:urllib.parse.Quoter
已被棄用:它並非預期的公開 API。(由 Gregory P. Smith 於 gh-88168 貢獻。)
Python 3.15 中待移除的項目¶
引入系統 (import system):
在模組上設定
__cached__
而沒有設定__spec__.cached
的做法已被棄用。在 Python 3.15 中,引入系統或標準函式庫將不再設定或考慮__cached__
。(gh-97879)在模組上設定
__package__
而沒有設定__spec__.parent
的做法已被棄用。在 Python 3.15 中,引入系統或標準函式庫將不再設定或考慮__package__
。(gh-97879)
-
自 Python 3.13 起,未記錄的
ctypes.SetPointerType()
函式已被棄用。
-
過時且很少使用的
CGIHTTPRequestHandler
自 Python 3.13 起已被棄用。不存在直接的替代。任何東西都比 CGI 更好地將 Web 伺服器與請求處理程序介接起來。自 Python 3.13 起,python -m http.server 命令列介面的
--cgi
旗標已被棄用。
-
getdefaultlocale()
已在 Python 3.11 中被棄用,原本計劃在 Python 3.13 中移除 (gh-90817),但被延後至 Python 3.15。請改用getlocale()
、setlocale()
和getencoding()
。 (由 Hugo van Kemenade 於 gh-111187 貢獻。)
-
PurePath.is_reserved()
已自 Python 3.13 被棄用。請用os.path.isreserved()
來偵測 Windows 上的保留路徑。
-
自 Python 3.13 起,
java_ver()
已被棄用。此函式僅對 Jython 支援有用,具有令人困惑的 API,基本上未經測試。
-
RLock()
在 Python 3.15 中將不接受任何引數。自 Python 3.14 起,傳遞任何引數的用法已被棄用,因為 Python 版本不允許任何引數,但 C 版本允許任意數量的位置或關鍵字引數,並忽略每個引數。
-
types.CodeType
:自 3.10 起,存取co_lnotab
已在 PEP 626 中被棄用,並計劃在 3.12 中移除,但只在 3.12 中於適當時發出DeprecationWarning
。可能在 3.15 中移除。(由 Nikita Sobolev 於 gh-101866 貢獻。)
-
用於建立
NamedTuple
類別的未以文件記錄之關鍵字引數語法 (Point = NamedTuple("Point", x=int, y=int)
) 已自 Python 3.13 棄用。請改用基於類別的語法或函式語法 (functional syntax)。自 Python 3.13 起,
typing.no_type_check_decorator()
裝飾器函式已被棄用。在typing
模組中使用了八年之後,它尚未得到任何主要型別檢查器的支援。
wave
:已棄用
Wave_read
和Wave_write
類別的getmark()
、setmark()
和getmarkers()
方法自 Python 3.13 被棄用。
Python 3.16 中待移除的項目¶
引入系統 (import system):
在模組上設定
__loader__
而沒有設定__spec__.loader
的做法將於 Python 3.16 被棄用。在 Python 3.16 中,引入系統或標準函式庫將不再設定或考慮__loader__
。
-
自 Python 3.3 起,
'u'
格式碼 (wchar_t
) 在文件中已被棄用,自 Python 3.13 起在 runtime 已被棄用。請使用'w'
格式碼 (Py_UCS4
) 來取代 Unicode 字元。
-
asyncio.iscoroutinefunction()
已被棄用並將在 Python 3.16 中移除,請改用inspect.iscoroutinefunction()
。(由 Jiahao Li 和 Kumar Aditya 於 gh-122875 貢獻。)
-
自 Python 3.12 起,布林型別的位元反轉
~True
或~False
已被棄用,因為它會產生不預期且不直觀的結果(-2
和-1
)。使用not x
代替布林值的邏輯否定。在極少數情況下,你需要對底層的整數進行位元反轉,請明確轉換為~int(x)
(~int(x)
)。
-
自 Python 3.14 起,
ExecError
例外已被棄用。自 Python 3.4 以來,它尚未被shutil
中的任何函式使用,現在是RuntimeError
的別名。
-
自 Python 3.14 起,
Class.get_methods
方法已被棄用。
sys
:自 Python 3.13 起,
_enablelegacywindowsfsencoding()
函式已被棄用。請改用PYTHONLEGACYWINDOWSFSENCODING
環境變數。
-
自 Python 3.13 起,未以文件記錄和未被使用的
TarFile.tarfile
屬性已被棄用。
未來版本中的待移除項目¶
以下 API 將在未來被移除,雖然目前尚未安排移除日期。
argparse
:已棄用巢狀引數群組和巢狀互斥群組。-
bool(NotImplemented)
。產生器:
throw(type, exc, tb)
和athrow(type, exc, tb)
簽名已被棄用:請改用throw(exc)
和athrow(exc)
,為單引數簽名。目前 Python 接受數值字面值後面立即接關鍵字,例如
0in x
、1or x
、0if 1else 2
。它讓表達式模糊且容易混淆,如[0x1for x in y]
(可以解釋為[0x1 for x in y]
或[0x1f or x in y]
)。如果數值字面值後立即接and
、else
、for
、if
、in
、is
和or
之一的關鍵字,則會引發語法警告。在未來版本中,它將被更改為語法錯誤。(gh-87999)__index__()
和__int__()
方法回傳非 int 型別的支援:這些方法將需要回傳int
的嚴格子類別實例。將
int()
委派給__trunc__()
方法。在
complex()
建構子中將複數作為 real 或 imag 引數傳遞現在已被棄用;它應該只作為單個位置引數傳遞。 (由 Serhiy Storchaka 於 gh-109218 貢獻。)
calendar
:calendar.January
和calendar.February
常數已被棄用並被calendar.JANUARY
和calendar.FEBRUARY
取代。 (由 Prince Roshan 於 gh-103636 貢獻。)-
utcnow()
:請改用datetime.datetime.now(tz=datetime.UTC)
。utcfromtimestamp()
:請改用datetime.datetime.fromtimestamp(timestamp, tz=datetime.UTC)
。
gettext
:複數值必須是整數。-
load_module()
method:請改用exec_module()
。cache_from_source()
debug_override 參數已被棄用:請改用 optimization 參數。
-
EntryPoints
元組介面。回傳值上的隱式
None
。
mailbox
:已棄用 StringIO 輸入和文本模式,請改用 BytesIO 和二進位模式。os
:在多執行緒行程中呼叫os.register_at_fork()
。pydoc.ErrorDuringImport
:exc_info 參數的元組值已被棄用,請用例外實例。re
:現在對正規表示式中的數值群組參照和群組名稱用了更嚴格的規則。現在只有 ASCII 數碼序列被接受作為數值參照。位元組模式和替換字串中的群組名稱現在只能包含 ASCII 字母、數碼和底線。(由 Serhiy Storchaka 於 gh-91760 貢獻。)sre_compile
、sre_constants
和sre_parse
模組。shutil
:rmtree()
的 onerror 參數在 Python 3.12 中已被棄用;請改用 onexc 參數。ssl
選項和協定:不帶協定引數的
ssl.SSLContext
已被棄用。ssl.SSLContext
:set_npn_protocols()
和selected_npn_protocol()
已被棄用:請改用 ALPN。ssl.OP_NO_SSL*
選項ssl.OP_NO_TLS*
選項ssl.PROTOCOL_SSLv3
ssl.PROTOCOL_TLS
ssl.PROTOCOL_TLSv1
ssl.PROTOCOL_TLSv1_1
ssl.PROTOCOL_TLSv1_2
ssl.TLSVersion.SSLv3
ssl.TLSVersion.TLSv1
ssl.TLSVersion.TLSv1_1
sysconfig.is_python_build()
的 check_home 參數已被棄用並被忽略。threading
方法:threading.Condition.notifyAll()
:請用notify_all()
。threading.Event.isSet()
:請用is_set()
。threading.Thread.isDaemon()
、threading.Thread.setDaemon()
:請用threading.Thread.daemon
屬性。threading.Thread.getName()
、threading.Thread.setName()
:請用threading.Thread.name
屬性。threading.currentThread()
:請用threading.current_thread()
。threading.activeCount()
:請用threading.active_count()
。
unittest.IsolatedAsyncioTestCase
:從測試案例中回傳非None
的值已被棄用。urllib.parse
已棄用函式:請改用urlparse()
。splitattr()
splithost()
splitnport()
splitpasswd()
splitport()
splitquery()
splittag()
splittype()
splituser()
splitvalue()
to_bytes()
urllib.request
:呼叫請求的URLopener
和FancyURLopener
風格已被棄用。請改用更新的urlopen()
函式和方法。wsgiref
:SimpleHandler.stdout.write()
不應該進行部分寫入。xml.etree.ElementTree
:已棄用對Element
的真值測試。在未來版本中,它將始終回傳True
。請改用明確的len(elem)
或elem is not None
測試。
已移除¶
asynchat 和 asyncore¶
configparser¶
Several names deprecated in the
configparser
way back in 3.2 have been removed per gh-89336:configparser.ParsingError
不再具有filename
屬性或引數。請改用source
屬性和引數。configparser
no longer has aSafeConfigParser
class. Use the shorterConfigParser
name instead.configparser.ConfigParser
no longer has areadfp
method. Useread_file()
instead.
distutils¶
ensurepip¶
Remove the bundled setuptools wheel from
ensurepip
, and stop installing setuptools in environments created byvenv
.pip (>= 22.1)
does not require setuptools to be installed in the environment.setuptools
-based (anddistutils
-based) packages can still be used withpip install
, since pip will providesetuptools
in the build environment it uses for building a package.easy_install
,pkg_resources
,setuptools
anddistutils
are no longer provided by default in environments created withvenv
or bootstrapped withensurepip
, since they are part of thesetuptools
package. For projects relying on these at runtime, thesetuptools
project should be declared as a dependency and installed separately (typically, using pip).(由 Pradyun Gedam 於 gh-95299 中貢獻。)
enum¶
ftplib¶
gzip¶
Remove the
filename
attribute ofgzip
'sgzip.GzipFile
, deprecated since Python 2.6, use thename
attribute instead. In write mode, thefilename
attribute added'.gz'
file extension if it was not present. (Contributed by Victor Stinner in gh-94196.)
hashlib¶
Remove the pure Python implementation of
hashlib
'shashlib.pbkdf2_hmac()
, deprecated in Python 3.10. Python 3.10 and newer requires OpenSSL 1.1.1 (PEP 644): this OpenSSL version provides a C implementation ofpbkdf2_hmac()
which is faster. (Contributed by Victor Stinner in gh-94199.)
importlib¶
現已完成清理
importlib
中許多過去已經棄用的東西:對
module_repr()
的參照和支援已刪除。(由 Barry Warsaw 在 gh-97850 中貢獻。)importlib.util.set_package
,importlib.util.set_loader
andimportlib.util.module_for_loader
have all been removed. (Contributed by Brett Cannon and Nikita Sobolev in gh-65961 and gh-97850.)Support for
find_loader()
andfind_module()
APIs have been removed. (Contributed by Barry Warsaw in gh-98040.)importlib.abc.Finder
,pkgutil.ImpImporter
, andpkgutil.ImpLoader
have been removed. (Contributed by Barry Warsaw in gh-98040.)
imp¶
The
imp
module has been removed. (Contributed by Barry Warsaw in gh-98040.)To migrate, consult the following correspondence table:
imp
importlib
imp.NullImporter
將
None
插入sys.path_importer_cache
imp.cache_from_source()
imp.find_module()
imp.get_magic()
imp.get_suffixes()
importlib.machinery.SOURCE_SUFFIXES
,importlib.machinery.EXTENSION_SUFFIXES
, andimportlib.machinery.BYTECODE_SUFFIXES
imp.get_tag()
imp.load_module()
imp.new_module(name)
types.ModuleType(name)
imp.reload()
imp.source_from_cache()
imp.load_source()
見下文
用以下取代
imp.load_source()
:import importlib.util import importlib.machinery def load_source(modname, filename): loader = importlib.machinery.SourceFileLoader(modname, filename) spec = importlib.util.spec_from_file_location(modname, filename, loader=loader) module = importlib.util.module_from_spec(spec) # The module is always executed and not cached in sys.modules. # Uncomment the following line to cache the module. # sys.modules[module.__name__] = module loader.exec_module(module) return module
移除
imp
函式和屬性、沒有替代方案:未以文件記錄的函式:
imp.init_builtin()
imp.load_compiled()
imp.load_dynamic()
imp.load_package()
imp.lock_held()
,imp.acquire_lock()
,imp.release_lock()
: the locking scheme has changed in Python 3.3 to per-module locks.imp.find_module()
常數:SEARCH_ERROR
、PY_SOURCE
、PY_COMPILED
、C_EXTENSION
、PY_RESOURCE
、PKG_DIRECTORY
、C_BUILTIN
、PY_FROZEN
、PY_CODERESOURCE
、IMP_HOOK
。
io¶
locale¶
Remove
locale
'slocale.format()
function, deprecated in Python 3.7: uselocale.format_string()
instead. (Contributed by Victor Stinner in gh-94226.)
smtpd¶
sqlite3¶
The following undocumented
sqlite3
features, deprecated in Python 3.10, are now removed:sqlite3.enable_shared_cache()
sqlite3.OptimizedUnicode
If a shared cache must be used, open the database in URI mode using the
cache=shared
query parameter.The
sqlite3.OptimizedUnicode
text factory has been an alias forstr
since Python 3.3. Code that previously set the text factory toOptimizedUnicode
can either usestr
explicitly, or rely on the default value which is alsostr
.(由 Erlend E. Aasland 於 gh-92548 中貢獻。)
ssl¶
Remove
ssl
'sssl.RAND_pseudo_bytes()
function, deprecated in Python 3.6: useos.urandom()
orssl.RAND_bytes()
instead. (Contributed by Victor Stinner in gh-94199.)Remove the
ssl.match_hostname()
function. It was deprecated in Python 3.7. OpenSSL performs hostname matching since Python 3.7, Python no longer uses thessl.match_hostname()
function. (Contributed by Victor Stinner in gh-94199.)Remove the
ssl.wrap_socket()
function, deprecated in Python 3.7: instead, create assl.SSLContext
object and call itsssl.SSLContext.wrap_socket
method. Any package that still usesssl.wrap_socket()
is broken and insecure. The function neither sends a SNI TLS extension nor validates the server hostname. Code is subject to CWE 295 (Improper Certificate Validation). (Contributed by Victor Stinner in gh-94199.)
unittest¶
移除許多
unittest
中被棄用已久的功能:許多
TestCase
方法別名:已棄用的別名
方法名稱
已棄用於
failUnless
3.1
failIf
3.1
failUnlessEqual
3.1
failIfEqual
3.1
failUnlessAlmostEqual
3.1
failIfAlmostEqual
3.1
failUnlessRaises
3.1
assert_
3.2
assertEquals
3.2
assertNotEquals
3.2
assertAlmostEquals
3.2
assertNotAlmostEquals
3.2
assertRegexpMatches
3.2
assertRaisesRegexp
3.2
assertNotRegexpMatches
3.5
You can use https://github.com/isidentical/teyit to automatically modernise your unit tests.
Undocumented and broken
TestCase
methodassertDictContainsSubset
(deprecated in Python 3.2).Undocumented
TestLoader.loadTestsFromModule
parameter use_load_tests (deprecated and ignored since Python 3.5).An alias of the
TextTestResult
class:_TextTestResult
(deprecated in Python 3.2).
(由 Serhiy Storchaka 於 gh-89325 中貢獻。)
webbrowser¶
Remove support for obsolete browsers from
webbrowser
. The removed browsers include: Grail, Mosaic, Netscape, Galeon, Skipstone, Iceape, Firebird, and Firefox versions 35 and below (gh-102871).
xml.etree.ElementTree¶
Remove the
ElementTree.Element.copy()
method of the pure Python implementation, deprecated in Python 3.10, use thecopy.copy()
function instead. The C implementation ofxml.etree.ElementTree
has nocopy()
method, only a__copy__()
method. (Contributed by Victor Stinner in gh-94383.)
zipimport¶
其他¶
Remove the
suspicious
rule from the documentationMakefile
andDoc/tools/rstlint.py
, both in favor of sphinx-lint. (Contributed by Julien Palard in gh-98179.)Remove the keyfile and certfile parameters from the
ftplib
,imaplib
,poplib
andsmtplib
modules, and the key_file, cert_file and check_hostname parameters from thehttp.client
module, all deprecated since Python 3.6. Use the context parameter (ssl_context inimaplib
) instead. (Contributed by Victor Stinner in gh-94172.)移除數個標準函式庫模組與測試中的
Jython
相容性修補程式。(由 Nikita Sobolev 於 gh-99482 中貢獻。)移除
ctypes
模組中的_use_broken_old_ctypes_structure_semantics_
旗標。(由 Nikita Sobolev 於 gh-99285 中貢獻。)
移植至 Python 3.12¶
This section lists previously described changes and other bugfixes that may require changes to your code.
Python API 的變更¶
More strict rules are now applied for numerical group references and group names in regular expressions. Only sequence of ASCII digits is now accepted as a numerical reference. The group name in bytes patterns and replacement strings can now only contain ASCII letters and digits and underscore. (Contributed by Serhiy Storchaka in gh-91760.)
Remove
randrange()
functionality deprecated since Python 3.10. Formerly,randrange(10.0)
losslessly converted torandrange(10)
. Now, it raises aTypeError
. Also, the exception raised for non-integer values such asrandrange(10.5)
orrandrange('10')
has been changed fromValueError
toTypeError
. This also prevents bugs whererandrange(1e25)
would silently select from a larger range thanrandrange(10**25)
. (Originally suggested by Serhiy Storchaka gh-86388.)argparse.ArgumentParser
changed encoding and error handler for reading arguments from file (e.g.fromfile_prefix_chars
option) from default text encoding (e.g.locale.getpreferredencoding(False)
) to filesystem encoding and error handler. Argument files should be encoded in UTF-8 instead of ANSI Codepage on Windows.Remove the
asyncore
-basedsmtpd
module deprecated in Python 3.4.7 and 3.5.4. A recommended replacement is theasyncio
-based aiosmtpd PyPI module.shlex.split()
: PassingNone
for s argument now raises an exception, rather than readingsys.stdin
. The feature was deprecated in Python 3.9. (Contributed by Victor Stinner in gh-94352.)The
os
module no longer accepts bytes-like paths, likebytearray
andmemoryview
types: only the exactbytes
type is accepted for bytes strings. (Contributed by Victor Stinner in gh-98393.)syslog.openlog()
andsyslog.closelog()
now fail if used in subinterpreters.syslog.syslog()
may still be used in subinterpreters, but now only ifsyslog.openlog()
has already been called in the main interpreter. These new restrictions do not apply to the main interpreter, so only a very small set of users might be affected. This change helps with interpreter isolation. Furthermore,syslog
is a wrapper around process-global resources, which are best managed from the main interpreter. (Contributed by Donghee Na in gh-99127.)The undocumented locking behavior of
cached_property()
is removed, because it locked across all instances of the class, leading to high lock contention. This means that a cached property getter function could now run more than once for a single instance, if two threads race. For most simple cached properties (e.g. those that are idempotent and simply calculate a value based on other attributes of the instance) this will be fine. If synchronization is needed, implement locking within the cached property getter function or around multi-threaded access points.sys._current_exceptions()
now returns a mapping from thread-id to an exception instance, rather than to a(typ, exc, tb)
tuple. (Contributed by Irit Katriel in gh-103176.)When extracting tar files using
tarfile
orshutil.unpack_archive()
, pass the filter argument to limit features that may be surprising or dangerous. See Extraction filters for details.The output of the
tokenize.tokenize()
andtokenize.generate_tokens()
functions is now changed due to the changes introduced in PEP 701. This means thatSTRING
tokens are not emitted any more for f-strings and the tokens described in PEP 701 are now produced instead:FSTRING_START
,FSTRING_MIDDLE
andFSTRING_END
are now emitted for f-string "string" parts in addition to the appropriate tokens for the tokenization in the expression components. For example for the f-stringf"start {1+1} end"
the old version of the tokenizer emitted:1,0-1,18: STRING 'f"start {1+1} end"'
while the new version emits:
1,0-1,2: FSTRING_START 'f"' 1,2-1,8: FSTRING_MIDDLE 'start ' 1,8-1,9: OP '{' 1,9-1,10: NUMBER '1' 1,10-1,11: OP '+' 1,11-1,12: NUMBER '1' 1,12-1,13: OP '}' 1,13-1,17: FSTRING_MIDDLE ' end' 1,17-1,18: FSTRING_END '"'
Additionally, there may be some minor behavioral changes as a consequence of the changes required to support PEP 701. Some of these changes include:
The
type
attribute of the tokens emitted when tokenizing some invalid Python characters such as!
has changed fromERRORTOKEN
toOP
.Incomplete single-line strings now also raise
tokenize.TokenError
as incomplete multiline strings do.Some incomplete or invalid Python code now raises
tokenize.TokenError
instead of returning arbitraryERRORTOKEN
tokens when tokenizing it.Mixing tabs and spaces as indentation in the same file is not supported anymore and will raise a
TabError
.
The
threading
module now expects the_thread
module to have an_is_main_interpreter
attribute. It is a function with no arguments that returnsTrue
if the current interpreter is the main interpreter.Any library or application that provides a custom
_thread
module should provide_is_main_interpreter()
. (See gh-112826.)
建置變更¶
Python no longer uses
setup.py
to build shared C extension modules. Build parameters like headers and libraries are detected inconfigure
script. Extensions are built byMakefile
. Most extensions usepkg-config
and fall back to manual detection. (Contributed by Christian Heimes in gh-93939.)va_start()
with two parameters, likeva_start(args, format),
is now required to build Python.va_start()
is no longer called with a single parameter. (Contributed by Kumar Aditya in gh-93207.)CPython now uses the ThinLTO option as the default link time optimization policy if the Clang compiler accepts the flag. (Contributed by Donghee Na in gh-89536.)
Add
COMPILEALL_OPTS
variable inMakefile
to overridecompileall
options (default:-j0
) inmake install
. Also merged the 3compileall
commands into a single command to build .pyc files for all optimization levels (0, 1, 2) at once. (Contributed by Victor Stinner in gh-99289.)Add platform triplets for 64-bit LoongArch:
loongarch64-linux-gnusf
loongarch64-linux-gnuf32
loongarch64-linux-gnu
(由 Zhang Na 於 gh-90656 中貢獻。)
PYTHON_FOR_REGEN
now require Python 3.10 or newer.Autoconf 2.71 and aclocal 1.16.4 is now required to regenerate
!configure
. (Contributed by Christian Heimes in gh-89886.)Windows builds and macOS installers from python.org now use OpenSSL 3.0.
C API 變更¶
新增功能¶
PEP 697: Introduce the Unstable C API tier, intended for low-level tools like debuggers and JIT compilers. This API may change in each minor release of CPython without deprecation warnings. Its contents are marked by the
PyUnstable_
prefix in names.程式碼物件建構函式:
PyUnstable_Code_New()
(自PyCode_New
重新命名)PyUnstable_Code_NewWithPosOnlyArgs()
(自PyCode_NewWithPosOnlyArgs
重新命名)
程式碼物件的額外儲存 (PEP 523):
PyUnstable_Eval_RequestCodeExtraIndex()
(自_PyEval_RequestCodeExtraIndex
重新命名)PyUnstable_Code_GetExtra()
(自_PyCode_GetExtra
重新命名)PyUnstable_Code_SetExtra()
(自_PyCode_SetExtra
重新命名)
原始名稱將可繼續使用,直到相應的 API 發生變更。
(由 Petr Viktorin 於 gh-101101 中貢獻。)
PEP 697: Add an API for extending types whose instance memory layout is opaque:
PyType_Spec.basicsize
可以為零或負數來指定繼承或擴充基底類別大小。PyObject_GetTypeData()
andPyType_GetTypeDataSize()
added to allow access to subclass-specific instance data.Py_TPFLAGS_ITEMS_AT_END
andPyObject_GetItemData()
added to allow safely extending certain variable-sized types, includingPyType_Type
.Py_RELATIVE_OFFSET
added to allow definingmembers
in terms of a subclass-specific struct.
(由 Petr Viktorin 於 gh-103509 中貢獻。)
Add the new limited C API function
PyType_FromMetaclass()
, which generalizes the existingPyType_FromModuleAndSpec()
using an additional metaclass argument. (Contributed by Wenzel Jakob in gh-93012.)API for creating objects that can be called using the vectorcall protocol was added to the Limited API:
The
Py_TPFLAGS_HAVE_VECTORCALL
flag is now removed from a class when the class's__call__()
method is reassigned. This makes vectorcall safe to use with mutable types (i.e. heap types without the immutable flag,Py_TPFLAGS_IMMUTABLETYPE
). Mutable types that do not overridetp_call
now inherit thePy_TPFLAGS_HAVE_VECTORCALL
flag. (Contributed by Petr Viktorin in gh-93274.)The
Py_TPFLAGS_MANAGED_DICT
andPy_TPFLAGS_MANAGED_WEAKREF
flags have been added. This allows extensions classes to support object__dict__
and weakrefs with less bookkeeping, using less memory and with faster access.API for performing calls using the vectorcall protocol was added to the Limited API:
This means that both the incoming and outgoing ends of the vector call protocol are now available in the Limited API. (Contributed by Wenzel Jakob in gh-98586.)
Add two new public functions,
PyEval_SetProfileAllThreads()
andPyEval_SetTraceAllThreads()
, that allow to set tracing and profiling functions in all running threads in addition to the calling one. (Contributed by Pablo Galindo in gh-93503.)Add new function
PyFunction_SetVectorcall()
to the C API which sets the vectorcall field of a givenPyFunctionObject
. (Contributed by Andrew Frost in gh-92257.)The C API now permits registering callbacks via
PyDict_AddWatcher()
,PyDict_Watch()
and related APIs to be called whenever a dictionary is modified. This is intended for use by optimizing interpreters, JIT compilers, or debuggers. (Contributed by Carl Meyer in gh-91052.)Add
PyType_AddWatcher()
andPyType_Watch()
API to register callbacks to receive notification on changes to a type. (Contributed by Carl Meyer in gh-91051.)Add
PyCode_AddWatcher()
andPyCode_ClearWatcher()
APIs to register callbacks to receive notification on creation and destruction of code objects. (Contributed by Itamar Oren in gh-91054.)Add
PyFrame_GetVar()
andPyFrame_GetVarString()
functions to get a frame variable by its name. (Contributed by Victor Stinner in gh-91248.)Add
PyErr_GetRaisedException()
andPyErr_SetRaisedException()
for saving and restoring the current exception. These functions return and accept a single exception object, rather than the triple arguments of the now-deprecatedPyErr_Fetch()
andPyErr_Restore()
. This is less error prone and a bit more efficient. (Contributed by Mark Shannon in gh-101578.)Add
_PyErr_ChainExceptions1
, which takes an exception instance, to replace the legacy-API_PyErr_ChainExceptions
, which is now deprecated. (Contributed by Mark Shannon in gh-101578.)Add
PyException_GetArgs()
andPyException_SetArgs()
as convenience functions for retrieving and modifying theargs
passed to the exception's constructor. (Contributed by Mark Shannon in gh-101578.)Add
PyErr_DisplayException()
, which takes an exception instance, to replace the legacy-apiPyErr_Display()
. (Contributed by Irit Katriel in gh-102755).
PEP 683: Introduce Immortal Objects, which allows objects to bypass reference counts, and related changes to the C-API:
_Py_IMMORTAL_REFCNT
:定義物件的參照計數as immortal.
_Py_IsImmortal
Checks if an object has the immortal reference count.PyObject_HEAD_INIT
這現在將初始化參照計數_Py_IMMORTAL_REFCNT
(與Py_BUILD_CORE
一起使用時)。
SSTATE_INTERNED_IMMORTAL
An identifier for interned unicode objectsthat are immortal.
SSTATE_INTERNED_IMMORTAL_STATIC
An identifier for interned unicodeobjects that are immortal and static
sys.getunicodeinternedsize
這會回傳 unicode 的總數objects that have been interned. This is now needed for
refleak.py
to correctly track reference counts and allocated blocks
(由 Eddie Elizondo 於 gh-84436 中貢獻。)
PEP 684: Add the new
Py_NewInterpreterFromConfig()
function andPyInterpreterConfig
, which may be used to create sub-interpreters with their own GILs. (See PEP 684: A Per-Interpreter GIL for more info.) (Contributed by Eric Snow in gh-104110.)In the limited C API version 3.12,
Py_INCREF()
andPy_DECREF()
functions are now implemented as opaque function calls to hide implementation details. (Contributed by Victor Stinner in gh-105387.)
移植至 Python 3.12¶
Legacy Unicode APIs based on
Py_UNICODE*
representation has been removed. Please migrate to APIs based on UTF-8 orwchar_t*
.Argument parsing functions like
PyArg_ParseTuple()
doesn't supportPy_UNICODE*
based format (e.g.u
,Z
) anymore. Please migrate to other formats for Unicode likes
,z
,es
, andU
.tp_weaklist
for all static builtin types is alwaysNULL
. This is an internal-only field onPyTypeObject
but we're pointing out the change in case someone happens to be accessing the field directly anyway. To avoid breakage, consider using the existing public C-API instead, or, if necessary, the (internal-only)_PyObject_GET_WEAKREFS_LISTPTR()
macro.This internal-only
PyTypeObject.tp_subclasses
may now not be a valid object pointer. Its type was changed to void* to reflect this. We mention this in case someone happens to be accessing the internal-only field directly.To get a list of subclasses, call the Python method
__subclasses__()
(usingPyObject_CallMethod()
, for example).Add support of more formatting options (left aligning, octals, uppercase hexadecimals,
intmax_t
,ptrdiff_t
,wchar_t
C strings, variable width and precision) inPyUnicode_FromFormat()
andPyUnicode_FromFormatV()
. (Contributed by Serhiy Storchaka in gh-98836.)An unrecognized format character in
PyUnicode_FromFormat()
andPyUnicode_FromFormatV()
now sets aSystemError
. In previous versions it caused all the rest of the format string to be copied as-is to the result string, and any extra arguments discarded. (Contributed by Serhiy Storchaka in gh-95781.)Fix wrong sign placement in
PyUnicode_FromFormat()
andPyUnicode_FromFormatV()
. (Contributed by Philip Georgi in gh-95504.)Extension classes wanting to add a
__dict__
or weak reference slot should usePy_TPFLAGS_MANAGED_DICT
andPy_TPFLAGS_MANAGED_WEAKREF
instead oftp_dictoffset
andtp_weaklistoffset
, respectively. The use oftp_dictoffset
andtp_weaklistoffset
is still supported, but does not fully support multiple inheritance (gh-95589), and performance may be worse. Classes declaringPy_TPFLAGS_MANAGED_DICT
must call_PyObject_VisitManagedDict()
and_PyObject_ClearManagedDict()
to traverse and clear their instance's dictionaries. To clear weakrefs, callPyObject_ClearWeakRefs()
, as before.The
PyUnicode_FSDecoder()
function no longer accepts bytes-like paths, likebytearray
andmemoryview
types: only the exactbytes
type is accepted for bytes strings. (Contributed by Victor Stinner in gh-98393.)The
Py_CLEAR
,Py_SETREF
andPy_XSETREF
macros now only evaluate their arguments once. If an argument has side effects, these side effects are no longer duplicated. (Contributed by Victor Stinner in gh-98724.)The interpreter's error indicator is now always normalized. This means that
PyErr_SetObject()
,PyErr_SetString()
and the other functions that set the error indicator now normalize the exception before storing it. (Contributed by Mark Shannon in gh-101578.)_Py_RefTotal
is no longer authoritative and only kept around for ABI compatibility. Note that it is an internal global and only available on debug builds. If you happen to be using it then you'll need to start using_Py_GetGlobalRefTotal()
.The following functions now select an appropriate metaclass for the newly created type:
Creating classes whose metaclass overrides
tp_new
is deprecated, and in Python 3.14+ it will be disallowed. Note that these functions ignoretp_new
of the metaclass, possibly allowing incomplete initialization.Note that
PyType_FromMetaclass()
(added in Python 3.12) already disallows creating classes whose metaclass overridestp_new
(__new__()
in Python).Since
tp_new
overrides almost everythingPyType_From*
functions do, the two are incompatible with each other. The existing behavior -- ignoring the metaclass for several steps of type creation -- is unsafe in general, since (meta)classes assume thattp_new
was called. There is no simple general workaround. One of the following may work for you:If you control the metaclass, avoid using
tp_new
in it:If initialization can be skipped, it can be done in
tp_init
instead.If the metaclass doesn't need to be instantiated from Python, set its
tp_new
toNULL
using thePy_TPFLAGS_DISALLOW_INSTANTIATION
flag. This makes it acceptable forPyType_From*
functions.
Avoid
PyType_From*
functions: if you don't need C-specific features (slots or setting the instance size), create types by calling the metaclass.If you know the
tp_new
can be skipped safely, filter the deprecation warning out usingwarnings.catch_warnings()
from Python.
PyOS_InputHook
andPyOS_ReadlineFunctionPointer
are no longer called in subinterpreters. This is because clients generally rely on process-wide global state (since these callbacks have no way of recovering extension module state).This also avoids situations where extensions may find themselves running in a subinterpreter that they don't support (or haven't yet been loaded in). See gh-104668 for more info.
PyLongObject
has had its internals changed for better performance. Although the internals ofPyLongObject
are private, they are used by some extension modules. The internal fields should no longer be accessed directly, instead the API functions beginningPyLong_...
should be used instead. Two new unstable API functions are provided for efficient access to the value ofPyLongObject
s which fit into a single machine word:Custom allocators, set via
PyMem_SetAllocator()
, are now required to be thread-safe, regardless of memory domain. Allocators that don't have their own state, including "hooks", are not affected. If your custom allocator is not already thread-safe and you need guidance then please create a new GitHub issue and CC@ericsnowcurrently
.
已棄用¶
In accordance with PEP 699, the
ma_version_tag
field inPyDictObject
is deprecated for extension modules. Accessing this field will generate a compiler warning at compile time. This field will be removed in Python 3.14. (Contributed by Ramvikrams and Kumar Aditya in gh-101193. PEP by Ken Jin.)棄用全域配置變數:
Py_HashRandomizationFlag
: 請改用PyConfig.use_hash_seed
和PyConfig.hash_seed
Py_LegacyWindowsFSEncodingFlag
: 請改用PyPreConfig.legacy_windows_fs_encoding
Py_LegacyWindowsStdioFlag
: 請改用PyConfig.legacy_windows_stdio
Py_FileSystemDefaultEncoding
: 請改用PyConfig.filesystem_encoding
Py_HasFileSystemDefaultEncoding
: 請改用PyConfig.filesystem_encoding
Py_FileSystemDefaultEncodeErrors
: 請改用PyConfig.filesystem_errors
Py_UTF8Mode
: 請改用PyPreConfig.utf8_mode
(參見Py_PreInitialize()
)
Py_InitializeFromConfig()
API 應改為與PyConfig
一起使用。(由 Victor Stinner 於 gh-77782 中貢獻。)Creating
immutable types
with mutable bases is deprecated and will be disabled in Python 3.14. (gh-95388)structmember.h
標頭已棄用,但仍可使用,且還沒有移除它的計畫。Its contents are now available just by including
Python.h
, with aPy
prefix added if it was missing:Type macros like
Py_T_INT
,Py_T_DOUBLE
, etc. (previouslyT_INT
,T_DOUBLE
, etc.)Py_READONLY
(先前為READONLY
)和Py_AUDIT_READ
(先前全大寫)旗標
數個項目不再從
Python.h
中公開:T_OBJECT
(請改用Py_T_OBJECT_EX
)T_NONE
(先前未記錄於文件上,且相當古怪)不做任何事的巨集
WRITE_RESTRICTED
。RESTRICTED
和READ_RESTRICTED
這兩個巨集,相當於Py_AUDIT_READ
。In some configurations,
<stddef.h>
is not included fromPython.h
. It should be included manually when usingoffsetof()
.
The deprecated header continues to provide its original contents under the original names. Your old code can stay unchanged, unless the extra include and non-namespaced macros bother you greatly.
(Contributed in gh-47146 by Petr Viktorin, based on earlier work by Alexander Belopolsky and Matthias Braun.)
PyErr_Fetch()
andPyErr_Restore()
are deprecated. UsePyErr_GetRaisedException()
andPyErr_SetRaisedException()
instead. (Contributed by Mark Shannon in gh-101578.)PyErr_Display()
已棄用,請改用PyErr_DisplayException()
。(由 Irit Katriel 於 gh-102755 中貢獻。)_PyErr_ChainExceptions
已棄用,請改用_PyErr_ChainExceptions1
。(由 Irit Katriel 於 gh-102192 中貢獻。)Using
PyType_FromSpec()
,PyType_FromSpecWithBases()
orPyType_FromModuleAndSpec()
to create a class whose metaclass overridestp_new
is deprecated. Call the metaclass instead.
Python 3.14 中待移除的項目¶
PyDictObject
中的ma_version_tag
欄位,用於擴充模組 (PEP 699;gh-101193)。設定 Python 初始化的函式,Python 3.11 中已被棄用:
PySys_SetArgvEx()
:請改以PyConfig.argv
設定。PySys_SetArgv()
:請改以PyConfig.argv
設定。Py_SetProgramName()`()
:請改以PyConfig.program_name
設定。Py_SetPythonHome()
:請改以PyConfig.home
設定。
Py_InitializeFromConfig()
API 應該與PyConfig
一起使用。全域設定變數:
Py_HashRandomizationFlag
:請改用PyConfig.use_hash_seed
和PyConfig.hash_seed
。Py_LegacyWindowsFSEncodingFlag
:請改用PyPreConfig.legacy_windows_fs_encoding
。Py_LegacyWindowsStdioFlag
:請改用PyConfig.legacy_windows_stdio
。Py_FileSystemDefaultEncoding
:請改用PyConfig.filesystem_encoding
。Py_HasFileSystemDefaultEncoding
:請改用PyConfig.filesystem_encoding
。Py_FileSystemDefaultEncodeErrors
:請改用PyConfig.filesystem_errors
。Py_UTF8Mode
:請改用PyPreConfig.utf8_mode
。(請見Py_PreInitialize()
)
Py_InitializeFromConfig()
API 應該與PyConfig
一起使用。
Python 3.15 中待移除的項目¶
libmpdecimal
的打包副本 (bundled copy)。PyWeakref_GetObject()
和PyWeakref_GET_OBJECT()
:請改用PyWeakref_GetRef()
。Py_UNICODE
型別與Py_UNICODE_WIDE
巨集:請改用wchar_t
。Python 初始化函式:
PySys_ResetWarnOptions()
:請改為清除sys.warnoptions
和warnings.filters
。Py_GetExecPrefix()
:請改用sys.base_exec_prefix
與sys.exec_prefix
。Py_GetPath()
:請改用sys.path
。Py_GetPythonHome()
:請改用PyConfig.home
或PYTHONHOME
環境變數。
未來版本中的待移除項目¶
下列 API 已被棄用並將會被移除,不過目前尚未訂定移除日期。
Py_TPFLAGS_HAVE_FINALIZE
:自 Python 3.8 起不再需要PySlice_GetIndicesEx()
:請改用PySlice_Unpack()
和PySlice_AdjustIndices()
。PyUnicode_AsDecodedObject()
:請改用PyCodec_Decode()
。PyUnicode_AsDecodedUnicode()
:請改用PyCodec_Decode()
。PyUnicode_AsEncodedObject()
:請改用PyCodec_Encode()
。PyUnicode_AsEncodedUnicode()
:請改用PyCodec_Encode()
。PyUnicode_READY()
:自 Python 3.12 起不再需要PyErr_Display()
:請改用PyErr_DisplayException()
。_PyErr_ChainExceptions()
:請改用_PyErr_ChainExceptions1
。PyBytesObject.ob_shash
成員:請改為呼叫PyObject_Hash()
。PyDictObject.ma_version_tag
成員。執行緒局部儲存 (Thread Local Storage, TLS) API:
已移除¶
Remove the
token.h
header file. There was never any public tokenizer C API. Thetoken.h
header file was only designed to be used by Python internals. (Contributed by Victor Stinner in gh-92651.)Legacy Unicode APIs have been removed. See PEP 623 for detail.
PyUnicode_WCHAR_KIND
PyUnicode_AS_UNICODE()
PyUnicode_AsUnicode()
PyUnicode_AsUnicodeAndSize()
PyUnicode_AS_DATA()
PyUnicode_FromUnicode()
PyUnicode_GET_SIZE()
PyUnicode_GetSize()
PyUnicode_GET_DATA_SIZE()
移除
PyUnicode_InternImmortal()
函式巨集。(由 Victor Stinner 於 gh-85858 中貢獻。)