https://github.com/python/cpython/commit/e4204e879eca7eaa9d4599e17711eb8b267dec8c commit: e4204e879eca7eaa9d4599e17711eb8b267dec8c branch: 3.13 author: Miss Islington (bot) <[email protected]> committer: serhiy-storchaka <[email protected]> date: 2024-10-26T21:37:06+03:00 summary:
[3.13] gh-84545: Clarify the 'extend' action documentation in argparse (GH-125870) (GH-125964) (cherry picked from commit da8673da362a2135cd621ac619d3aced6bb55100) Co-authored-by: Serhiy Storchaka <[email protected]> files: M Doc/library/argparse.rst diff --git a/Doc/library/argparse.rst b/Doc/library/argparse.rst index 607364791bc8c1..39fdccfd5deaf0 100644 --- a/Doc/library/argparse.rst +++ b/Doc/library/argparse.rst @@ -692,6 +692,21 @@ how the command-line arguments should be handled. The supplied actions are: >>> parser.parse_args('--str --int'.split()) Namespace(types=[<class 'str'>, <class 'int'>]) +* ``'extend'`` - This stores a list and appends each item from the multi-value + argument list to it. + The ``'extend'`` action is typically used with the nargs_ keyword argument + value ``'+'`` or ``'*'``. + Note that when nargs_ is ``None`` (the default) or ``'?'``, each + character of the argument string will be appended to the list. + Example usage:: + + >>> parser = argparse.ArgumentParser() + >>> parser.add_argument("--foo", action="extend", nargs="+", type=str) + >>> parser.parse_args(["--foo", "f1", "--foo", "f2", "f3", "f4"]) + Namespace(foo=['f1', 'f2', 'f3', 'f4']) + + .. versionadded:: 3.8 + * ``'count'`` - This counts the number of times a keyword argument occurs. For example, this is useful for increasing verbosity levels:: @@ -717,17 +732,6 @@ how the command-line arguments should be handled. The supplied actions are: >>> parser.parse_args(['--version']) PROG 2.0 -* ``'extend'`` - This stores a list, and extends each argument value to the - list. - Example usage:: - - >>> parser = argparse.ArgumentParser() - >>> parser.add_argument("--foo", action="extend", nargs="+", type=str) - >>> parser.parse_args(["--foo", "f1", "--foo", "f2", "f3", "f4"]) - Namespace(foo=['f1', 'f2', 'f3', 'f4']) - - .. versionadded:: 3.8 - Only actions that consume command-line arguments (e.g. ``'store'``, ``'append'`` or ``'extend'``) can be used with positional arguments. _______________________________________________ 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]
