FazBrowse GitHub Viewer | Trending |
URL:
| Home
Tools: [Download Repo ZIP]   [Original HTTPS Page]

gh-104010: Separate and improve docs for `typing.get_origin` and `typing.get_args` by chgnrdv · Pull Request #104013 · python/cpython · GitHub

/ cpython Public
31 changes: 22 additions & 9 deletions Doc/library/typing.rst
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters. Learn more about bidirectional Unicode characters
Original file line number Diff line number Diff line change
Expand Up @@ -2881,24 +2881,37 @@ Introspection helpers
if a default value equal to ``None`` was set.
Now the annotation is returned unchanged.

.. function:: get_args(tp)
.. function:: get_origin(tp)

Provide basic introspection for generic types and special typing forms.

For a typing object of the form ``X[Y, Z, ...]`` these functions return
``X`` and ``(Y, Z, ...)``. If ``X`` is a generic alias for a builtin or
Get the unsubscripted version of a type: for a typing object of the form
``X[Y, Z, ...]`` return ``X``. If ``X`` is a generic alias for a builtin or
:mod:`collections` class, it gets normalized to the original class.
If ``X`` is an instance of :class:`ParamSpecArgs` or :class:`ParamSpecKwargs`,
return the underlying :class:`ParamSpec`.
Return ``None`` for unsupported objects.
Examples::

assert get_origin(str) is None
assert get_origin(Dict[str, int]) is dict
assert get_origin(Union[int, str]) is Union
P = ParamSpec('P')
assert get_origin(P.args) is P
assert get_origin(P.kwargs) is P

.. versionadded:: 3.8

.. function:: get_args(tp)

Get type arguments with all substitutions performed: for a typing object
of the form ``X[Y, Z, ...]`` return ``(Y, Z, ...)``.
If ``X`` is a union or :class:`Literal` contained in another
generic type, the order of ``(Y, Z, ...)`` may be different from the order
of the original arguments ``[Y, Z, ...]`` due to type caching.
For unsupported objects return ``None`` and ``()`` correspondingly.
Return ``()`` for unsupported objects.
Examples::

assert get_origin(Dict[str, int]) is dict
assert get_args(int) == ()
assert get_args(Dict[int, str]) == (int, str)

assert get_origin(Union[int, str]) is Union
assert get_args(Union[int, str]) == (int, str)

.. versionadded:: 3.8
Expand Down

Back | FazBrowse Home | New Git URL