https://github.com/python/cpython/commit/52f1fb6f7dba31ccbe28f555f199c7d29f137581 commit: 52f1fb6f7dba31ccbe28f555f199c7d29f137581 branch: 3.12 author: Miss Islington (bot) <[email protected]> committer: AlexWaygood <[email protected]> date: 2024-04-02T09:29:10Z summary:
[3.12] Link to the Python type system specification (GH-117400) (#117448) Co-authored-by: Shantanu <[email protected]> files: M Doc/library/typing.rst diff --git a/Doc/library/typing.rst b/Doc/library/typing.rst index 74f358d713ef18..cea1f37a0764c4 100644 --- a/Doc/library/typing.rst +++ b/Doc/library/typing.rst @@ -23,27 +23,25 @@ -------------- -This module provides runtime support for type hints. For the original -specification of the typing system, see :pep:`484`. For a simplified -introduction to type hints, see :pep:`483`. +This module provides runtime support for type hints. +Consider the function below:: -The function below takes and returns a string and is annotated as follows:: + def moon_weight(earth_weight: float) -> str: + return f'On the moon, you would weigh {earth_weight * 0.166} kilograms.' - def greeting(name: str) -> str: - return 'Hello ' + name +The function ``moon_weight`` takes an argument expected to be an instance of :class:`float`, +as indicated by the *type hint* ``earth_weight: float``. The function is expected to +return an instance of :class:`str`, as indicated by the ``-> str`` hint. -In the function ``greeting``, the argument ``name`` is expected to be of type -:class:`str` and the return type :class:`str`. Subtypes are accepted as -arguments. +While type hints can be simple classes like :class:`float` or :class:`str`, +they can also be more complex. The :mod:`typing` module provides a vocabulary of +more advanced type hints. New features are frequently added to the ``typing`` module. The `typing_extensions <https://pypi.org/project/typing-extensions/>`_ package provides backports of these new features to older versions of Python. -For a summary of deprecated features and a deprecation timeline, please see -`Deprecation Timeline of Major Features`_. - .. seealso:: `"Typing cheat sheet" <https://mypy.readthedocs.io/en/stable/cheat_sheet_py3.html>`_ @@ -61,67 +59,11 @@ For a summary of deprecated features and a deprecation timeline, please see .. _relevant-peps: -Relevant PEPs -============= - -Since the initial introduction of type hints in :pep:`484` and :pep:`483`, a -number of PEPs have modified and enhanced Python's framework for type -annotations: - -.. raw:: html - - <details> - <summary><a style="cursor:pointer;">The full list of PEPs</a></summary> - -* :pep:`526`: Syntax for Variable Annotations - *Introducing* syntax for annotating variables outside of function - definitions, and :data:`ClassVar` -* :pep:`544`: Protocols: Structural subtyping (static duck typing) - *Introducing* :class:`Protocol` and the - :func:`@runtime_checkable<runtime_checkable>` decorator -* :pep:`585`: Type Hinting Generics In Standard Collections - *Introducing* :class:`types.GenericAlias` and the ability to use standard - library classes as :ref:`generic types<types-genericalias>` -* :pep:`586`: Literal Types - *Introducing* :data:`Literal` -* :pep:`589`: TypedDict: Type Hints for Dictionaries with a Fixed Set of Keys - *Introducing* :class:`TypedDict` -* :pep:`591`: Adding a final qualifier to typing - *Introducing* :data:`Final` and the :func:`@final<final>` decorator -* :pep:`593`: Flexible function and variable annotations - *Introducing* :data:`Annotated` -* :pep:`604`: Allow writing union types as ``X | Y`` - *Introducing* :data:`types.UnionType` and the ability to use - the binary-or operator ``|`` to signify a - :ref:`union of types<types-union>` -* :pep:`612`: Parameter Specification Variables - *Introducing* :class:`ParamSpec` and :data:`Concatenate` -* :pep:`613`: Explicit Type Aliases - *Introducing* :data:`TypeAlias` -* :pep:`646`: Variadic Generics - *Introducing* :data:`TypeVarTuple` -* :pep:`647`: User-Defined Type Guards - *Introducing* :data:`TypeGuard` -* :pep:`655`: Marking individual TypedDict items as required or potentially missing - *Introducing* :data:`Required` and :data:`NotRequired` -* :pep:`673`: Self type - *Introducing* :data:`Self` -* :pep:`675`: Arbitrary Literal String Type - *Introducing* :data:`LiteralString` -* :pep:`681`: Data Class Transforms - *Introducing* the :func:`@dataclass_transform<dataclass_transform>` decorator -* :pep:`692`: Using ``TypedDict`` for more precise ``**kwargs`` typing - *Introducing* a new way of typing ``**kwargs`` with :data:`Unpack` and - :data:`TypedDict` -* :pep:`695`: Type Parameter Syntax - *Introducing* builtin syntax for creating generic functions, classes, and type aliases. -* :pep:`698`: Adding an override decorator to typing - *Introducing* the :func:`@override<override>` decorator - -.. raw:: html - - </details> - <br> +Specification for the Python Type System +======================================== + +The canonical, up-to-date specification of the Python type system can be +found at `"Specification for the Python type system" <https://typing.readthedocs.io/en/latest/spec/index.html>`_. .. _type-aliases: _______________________________________________ Python-checkins mailing list -- [email protected] To unsubscribe send an email to [email protected] https://mail.python.org/mailman3/lists/python-checkins.python.org/ Member address: [email protected]
