From bbd54ba84f96cb62241a760b27abe66057ecc0ea Mon Sep 17 00:00:00 2001 From: wulmer Date: Sun, 23 Jul 2023 11:00:42 +0200 Subject: [PATCH] gh-71261: Add paragraph on shadowing submodules with star imports (#107004) --- Doc/tutorial/modules.rst | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/Doc/tutorial/modules.rst b/Doc/tutorial/modules.rst index 3bd034bcc9703f8..734dd1cfe6871ac 100644 --- a/Doc/tutorial/modules.rst +++ b/Doc/tutorial/modules.rst @@ -512,6 +512,22 @@ code:: This would mean that ``from sound.effects import *`` would import the three named submodules of the :mod:`sound.effects` package. +Be aware that submodules might become shadowed by locally defined names. For +example, if you added a ``reverse`` function to the +:file:`sound/effects/__init__.py` file, the ``from sound.effects import *`` +would only import the two submodules ``echo`` and ``surround``, but *not* the +``reverse`` submodule, because it is shadowed by the locally defined +``reverse`` function:: + + __all__ = [ + "echo", # refers to the 'echo.py' file + "surround", # refers to the 'surround.py' file + "reverse", # !!! refers to the 'reverse' function now !!! + ] + + def reverse(msg: str): # <-- this name shadows the 'reverse.py' submodule + return msg[::-1] # in the case of a 'from sound.effects import *' + If ``__all__`` is not defined, the statement ``from sound.effects import *`` does *not* import all submodules from the package :mod:`sound.effects` into the current namespace; it only ensures that the package :mod:`sound.effects` has