- Fix the runtime behavior of type parameters with defaults (PEP 696). Patch by Nadir Chowdhury.
- Fix minor discrepancy between error messages produced by
typingandtyping_extensionson Python 3.10. Patch by Jelle Zijlstra. - When
include_extra=False,get_type_hints()now stripsReadOnlyfrom the annotation.
This feature release adds support for PEP 728 (TypedDict with extra
items) and PEP 742 (TypeIs).
There are no changes since 4.10.0rc1.
- Add support for PEP 728, supporting the
closedkeyword argument and the special__extra_items__key for TypedDict. Patch by Zixuan James Li. - Add support for PEP 742, adding
typing_extensions.TypeIs. Patch by Jelle Zijlstra. - Drop runtime error when a read-only
TypedDictitem overrides a mutable one. Type checkers should still flag this as an error. Patch by Jelle Zijlstra. - Speedup
issubclass()checks against simple runtime-checkable protocols by around 6% (backporting python/cpython#112717, by Alex Waygood). - Fix a regression in the implementation of protocols where
typing.Protocolclasses that were not marked as@runtime_checkablewould be unnecessarily introspected, potentially causing exceptions to be raised if the protocol had problematic members. Patch by Alex Waygood, backporting python/cpython#113401.
This feature release adds typing_extensions.ReadOnly, as specified
by PEP 705, and makes various other improvements, especially to
@typing_extensions.deprecated().
There are no changes since 4.9.0rc1.
- Add support for PEP 705, adding
typing_extensions.ReadOnly. Patch by Jelle Zijlstra. - All parameters on
NewType.__call__are now positional-only. This means that the signature oftyping_extensions.NewType.__call__now exactly matches the signature oftyping.NewType.__call__. Patch by Alex Waygood. - Fix bug with using
@deprecatedon a mixin class. Inheriting from a deprecated class now raises aDeprecationWarning. Patch by Jelle Zijlstra. @deprecatednow gives a better error message if you pass a non-strargument to themsgparameter. Patch by Alex Waygood.@deprecatedis now implemented as a class for better introspectability. Patch by Jelle Zijlstra.- Exclude
__match_args__fromProtocolmembers. Backport of python/cpython#110683 by Nikita Sobolev. - When creating a
typing_extensions.NamedTupleclass, ensure__set_name__is called on all objects that define__set_name__and exist in the values of theNamedTupleclass's class dictionary. Patch by Alex Waygood, backporting python/cpython#111876. - Improve the error message when trying to call
issubclass()against aProtocolthat has non-method members. Patch by Alex Waygood (backporting python/cpython#112344, by Randolph Scholz).
No changes since 4.8.0rc1.
- Add
typing_extensions.Doc, as proposed by PEP 727. Patch by Sebastián Ramírez. - Drop support for Python 3.7 (including PyPy-3.7). Patch by Alex Waygood.
- Fix bug where
get_original_bases()would return incorrect results when called on a concrete subclass of a generic class. Patch by Alex Waygood (backporting python/cpython#107584, by James Hilton-Balfe). - Fix bug where
ParamSpec(default=...)would raise aTypeErroron Python versions <3.11. Patch by James Hilton-Balfe
- Fix support for
TypedDict,NamedTupleandis_protocolon PyPy-3.7 and PyPy-3.8. Patch by Alex Waygood. Note that PyPy-3.7 and PyPy-3.8 are unsupported by the PyPy project. The next feature release of typing-extensions will drop support for PyPy-3.7 and may also drop support for PyPy-3.8.
- This is expected to be the last feature release supporting Python 3.7, which reaches its end of life on June 27, 2023. Version 4.8.0 will support only Python 3.8.0 and up.
- Fix bug where a
typing_extensions.Protocolclass that had one or more non-callable members would raiseTypeErrorwhenissubclass()was called against it, even if it defined a custom__subclasshook__method. The correct behaviour -- which has now been restored -- is not to raiseTypeErrorin these situations if a custom__subclasshook__method is defined. Patch by Alex Waygood (backporting python/cpython#105976).
- Add
typing_extensions.get_protocol_membersandtyping_extensions.is_protocol(backport of CPython PR #104878). Patch by Jelle Zijlstra. typing_extensionsnow re-exports all names in the standard library'stypingmodule, except the deprecatedByteString. Patch by Jelle Zijlstra.- Due to changes in the implementation of
typing_extensions.Protocol,typing.runtime_checkablecan now be used ontyping_extensions.Protocol(previously, users had to usetyping_extensions.runtime_checkableif they were usingtyping_extensions.Protocol). - Align the implementation of
TypedDictwith the implementation in the standard library on Python 3.9 and higher.typing_extensions.TypedDictis now a function instead of a class. The private functions_check_fails,_dict_new, and_typeddict_newhave been removed.is_typeddictnow returnsFalsewhen called withTypedDictitself as the argument. Patch by Jelle Zijlstra. - Declare support for Python 3.12. Patch by Jelle Zijlstra.
- Fix tests on Python 3.13, which removes support for creating
TypedDictclasses through the keyword-argument syntax. Patch by Jelle Zijlstra. - Fix a regression introduced in v4.6.3 that meant that
issubclass(object, typing_extensions.Protocol)would erroneously raiseTypeError. Patch by Alex Waygood (backporting the CPython PR python/cpython#105239). - Allow
Protocolclasses to inherit fromtyping_extensions.Bufferorcollections.abc.Buffer. Patch by Alex Waygood (backporting python/cpython#104827, by Jelle Zijlstra). - Allow classes to inherit from both
typing.Protocolandtyping_extensions.Protocolsimultaneously. Since v4.6.0, this causedTypeErrorto be raised due to a metaclass conflict. Patch by Alex Waygood. - Backport several deprecations from CPython relating to unusual ways to
create
TypedDicts andNamedTuples. CPython PRs #105609 and #105780 by Alex Waygood;typing_extensionsbackport by Jelle Zijlstra.- Creating a
NamedTupleusing the functional syntax with keyword arguments (NT = NamedTuple("NT", a=int)) is now deprecated. - Creating a
NamedTuplewith zero fields using the syntaxNT = NamedTuple("NT")orNT = NamedTuple("NT", None)is now deprecated. - Creating a
TypedDictwith zero fields using the syntaxTD = TypedDict("TD")orTD = TypedDict("TD", None)is now deprecated.
- Creating a
- Fix bug on Python 3.7 where a protocol
Xthat had a memberawould not be considered an implicit subclass of an unrelated protocolYthat only has a membera. Where the members ofXare a superset of the members ofY,Xshould always be considered a subclass ofYiffYis a runtime-checkable protocol that only has callable members. Patch by Alex Waygood (backporting CPython PR python/cpython#105835).
- Fix a regression introduced in v4.6.0 in the implementation of
runtime-checkable protocols. The regression meant
that doing
class Foo(X, typing_extensions.Protocol), whereXwas a class that hadabc.ABCMetaas its metaclass, would then cause subsequentisinstance(1, X)calls to erroneously raiseTypeError. Patch by Alex Waygood (backporting the CPython PR python/cpython#105152). - Sync the repository's LICENSE file with that of CPython.
typing_extensionsis distributed under the same license as CPython itself. - Skip a problematic test on Python 3.12.0b1. The test fails on 3.12.0b1 due to
a bug in CPython, which will be fixed in 3.12.0b2. The
typing_extensionstest suite now passes on 3.12.0b1.
- Fix use of
@deprecatedon classes with__new__but no__init__. Patch by Jelle Zijlstra. - Fix regression in version 4.6.1 where comparing a generic class against a
runtime-checkable protocol using
isinstance()would causeAttributeErrorto be raised if using Python 3.7.
- Change deprecated
@runtimeto formal API@runtime_checkablein the error message. Patch by Xuehai Pan. - Fix regression in 4.6.0 where attempting to define a
Protocolthat was generic over aParamSpecor aTypeVarTuplewould causeTypeErrorto be raised. Patch by Alex Waygood.
-
typing_extensionsis now documented at https://typing-extensions.readthedocs.io/en/latest/. Patch by Jelle Zijlstra. -
Add
typing_extensions.Buffer, a marker class for buffer types, as proposed by PEP 688. Equivalent tocollections.abc.Bufferin Python 3.12. Patch by Jelle Zijlstra. -
Backport two CPython PRs fixing various issues with
typing.Literal: python/cpython#23294 and python/cpython#23383. Both CPython PRs were originally by Yurii Karabas, and both were backported to Python >=3.9.1, but no earlier. Patch by Alex Waygood.A side effect of one of the changes is that equality comparisons of
Literalobjects will now raise aTypeErrorif one of theLiteralobjects being compared has a mutable parameter. (Using mutable parameters withLiteralis not supported by PEP 586 or by any major static type checkers.) -
Literalis now reimplemented on all Python versions <= 3.10.0. Thetyping_extensionsversion does not suffer from the bug that was fixed in python/cpython#29334. (The CPython bugfix was backported to CPython 3.10.1 and 3.9.8, but no earlier.) -
Backport CPython PR 26067 (originally by Yurii Karabas), ensuring that
isinstance()calls on protocols raiseTypeErrorwhen the protocol is not decorated with@runtime_checkable. Patch by Alex Waygood. -
Backport several significant performance improvements to runtime-checkable protocols that have been made in Python 3.12 (see python/cpython#74690 for details). Patch by Alex Waygood.
A side effect of one of the performance improvements is that 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. See "What's New in Python 3.12" for more details. -
isinstance()checks against runtime-checkable protocols now useinspect.getattr_static()rather thanhasattr()to lookup whether attributes exist (backporting python/cpython#103034). 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 on older versions oftyping_extensionsmay no longer be considered instances of that protocol using the new release, and vice versa. Most users are unlikely to be affected by this change. Patch by Alex Waygood. -
Backport the ability to define
__init__methods on Protocol classes, a change made in Python 3.11 (originally implemented in python/cpython#31628 by Adrian Garcia Badaracco). Patch by Alex Waygood. -
Speedup
isinstance(3, typing_extensions.SupportsIndex)by >10x on Python <3.12. Patch by Alex Waygood. -
Add
typing_extensionsversions ofSupportsInt,SupportsFloat,SupportsComplex,SupportsBytes,SupportsAbsandSupportsRound. These have the same semantics as the versions from thetypingmodule, butisinstance()checks against thetyping_extensionsversions are >10x faster at runtime on Python <3.12. Patch by Alex Waygood. -
Add
__orig_bases__to non-generic TypedDicts, call-based TypedDicts, and call-based NamedTuples. Other TypedDicts and NamedTuples already had the attribute. Patch by Adrian Garcia Badaracco. -
Add
typing_extensions.get_original_bases, a backport oftypes.get_original_bases, introduced in Python 3.12 (CPython PR python/cpython#101827, originally by James Hilton-Balfe). Patch by Alex Waygood.This function should always produce correct results when called on classes constructed using features from
typing_extensions. However, it may produce incorrect results when called on someNamedTupleorTypedDictclasses that usetyping.{NamedTuple,TypedDict}on Python <=3.11. -
Constructing a call-based
TypedDictusing keyword arguments for the fields now causes aDeprecationWarningto be emitted. This matches the behaviour oftyping.TypedDicton 3.11 and 3.12. -
Backport the implementation of
NewTypefrom 3.10 (where it is implemented as a class rather than a function). This allows user-definedNewTypes to be pickled. Patch by Alex Waygood. -
Fix tests and import on Python 3.12, where
typing.TypeVarcan no longer be subclassed. Patch by Jelle Zijlstra. -
Add
typing_extensions.TypeAliasType, a backport oftyping.TypeAliasTypefrom PEP 695. Patch by Jelle Zijlstra. -
Backport changes to the repr of
typing.Unpackthat were made in order to implement PEP 692 (backport of python/cpython#104048). Patch by Alex Waygood.
- Runtime support for PEP 702, adding
typing_extensions.deprecated. Patch by Jelle Zijlstra. - Add better default value for TypeVar
defaultparameter, PEP 696. Enables runtime check ifNonewas passed as default. Patch by Marc Mueller (@cdce8p). - The
@typing_extensions.overridedecorator now sets the.__override__attribute. Patch by Steven Troxler. - Fix
get_type_hints()on cross-module inheritedTypedDictin 3.9 and 3.10. Patch by Carl Meyer. - Add
frozen_defaultparameter ondataclass_transform. Patch by Erik De Bonte.
- Add
typing_extensions.Anya backport of python 3.11's Any class which is subclassable at runtime. (backport from python/cpython#31841, by Shantanu and Jelle Zijlstra). Patch by James Hilton-Balfe (@Gobot1234). - Add initial support for TypeVarLike
defaultparameter, PEP 696. Patch by Marc Mueller (@cdce8p). - Runtime support for PEP 698, adding
typing_extensions.override. Patch by Jelle Zijlstra. - Add the
infer_varianceparameter toTypeVar, as specified in PEP 695. Patch by Jelle Zijlstra.
- Add
typing_extensions.NamedTuple, allowing for genericNamedTuples on Python <3.11 (backport from python/cpython#92027, by Serhiy Storchaka). Patch by Alex Waygood (@AlexWaygood). - Adjust
typing_extensions.TypedDictto allow for genericTypedDicts on Python <3.11 (backport from python/cpython#27663, by Samodya Abey). Patch by Alex Waygood (@AlexWaygood).
- Re-export
typing.Unpackandtyping.TypeVarTupleon Python 3.11. - Add
ParamSpecArgsandParamSpecKwargsto__all__. - Improve "accepts only single type" error messages.
- Improve the distributed package. Patch by Marc Mueller (@cdce8p).
- Update
typing_extensions.dataclass_transformto rename thefield_descriptorsparameter tofield_specifiersand accept arbitrary keyword arguments. - Add
typing_extensions.get_overloadsandtyping_extensions.clear_overloads, and add registry support totyping_extensions.overload. Backport from python/cpython#89263. - Add
typing_extensions.assert_type. Backport from bpo-46480. - Drop support for Python 3.6. Original patch by Adam Turner (@AA-Turner).
- Fix importing
typing_extensionson Python 3.7.0 and 3.7.1. Original patch by Nikita Sobolev (@sobolevn).
- Runtime support for PEP 646, adding
typing_extensions.TypeVarTupleandtyping_extensions.Unpack. - Add interaction of
RequiredandNotRequiredwith__required_keys__,__optional_keys__andget_type_hints(). Patch by David Cabot (@d-k-bo). - Runtime support for PEP 675 and
typing_extensions.LiteralString. - Add
Neverandassert_never. Backport from bpo-46475. ParamSpecargs and kwargs are now equal to themselves. Backport from bpo-46676. Patch by Gregory Beauregard (@GBeauregard).- Add
reveal_type. Backport from bpo-46414. - Runtime support for PEP 681 and
typing_extensions.dataclass_transform. Annotatedcan now wrapClassVarandFinal. Backport from bpo-46491. Patch by Gregory Beauregard (@GBeauregard).- Add missed
RequiredandNotRequiredto__all__. Patch by Yuri Karabas (@uriyyo). - The
@finaldecorator now sets the__final__attribute on the decorated object to allow runtime introspection. Backport from bpo-46342. - Add
is_typeddict. Patch by Chris Moradi (@chrismoradi) and James Hilton-Balfe (@Gobot1234).
- Fix broken sdist in release 4.0.0. Patch by Adam Turner (@AA-Turner).
- Fix equality comparison for
RequiredandNotRequired. Patch by Jelle Zijlstra (@jellezijlstra). - Fix usage of
Selfas a type argument. Patch by Chris Wesseling (@CharString) and James Hilton-Balfe (@Gobot1234).
- Starting with version 4.0.0, typing_extensions uses Semantic Versioning. See the README for more information.
- Dropped support for Python versions 3.5 and older, including Python 2.7.
- Simplified backports for Python 3.6.0 and newer. Patch by Adam Turner (@AA-Turner).
- Runtime support for PEP 673 and
typing_extensions.Self. Patch by James Hilton-Balfe (@Gobot1234). - Runtime support for PEP 655 and
typing_extensions.RequiredandNotRequired. Patch by David Foster (@davidfstr).
The following non-exported but non-private names have been removed as they are unneeded for supporting Python 3.6 and newer.
- TypingMeta
- OLD_GENERICS
- SUBS_TREE
- HAVE_ANNOTATED
- HAVE_PROTOCOLS
- V_co
- VT_co
Prior to release 4.0.0 we did not provide a changelog. Please check the Git history for details.