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Clean-up the argparse docs quick links table (GH-91726)

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Raymond Hettinger 2022-04-20 01:21:54 -05:00 • committed by GitHub
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Doc/library/argparse.rst
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@ -26,73 +26,51 @@ module also automatically generates help and usage messages and issues errors
when users give the program invalid arguments. when users give the program invalid arguments.
Summary
-------
Core Functionality Core Functionality
^^^^^^^^^^^^^^^^^^ ------------------
The :mod:`argparse` module's support for command-line interfaces is built The :mod:`argparse` module's support for command-line interfaces is built
from the following: around an instance of :class:`argparse.ArgumentParser`. It is a container for
argument specifications and has options that apply the parser as whole::
The :class:`argparse.ArgumentParser` creates a new :class:`ArgumentParser` parser = argparse.ArgumentParser(
object. Commonly used arguments include prog_, description_, and prog = 'ProgramName',
formatter_class_. For example, the user can create an instance of description = 'What the program does',
:class:`ArgumentParser` through the following:: epilog = 'Text at the bottom of help')
>>> parser = argparse.ArgumentParser(prog='PROG', description='DESC', The :func:`ArgumentParser.add_argument` function attaches individual argument
... formatter_class=argparse.RawDescriptionHelpFormatter) specifications to the parser. It supports positional arguments, options that
accept values, and on/off flags::
The :func:`ArgumentParser.add_argument` is a function that is used parser.add_argument('filename') # positional argument
to define how a single command-line argument should be parsed. Commonly used parser.add_argument('-c', '--count') # option that takes value
arguments include `name or flags`_, action_, default_, type_, required_, parser.add_argument('-v', '--verbose',
and help_. An example of the function :func:`ArgumentParser.add_argument` action='store_true') # on/off flag
is as follows::
>>> parser.add_argument('-v', '--verbose', action='store_true', The :func:`ArgumentParser.parse_args` function runs the parser and puts
... help='Show various debugging information') the extracted data in a :class:`argparse.Namespace` object::
args = parser.parse_args()
print(args.filename, args.count, args.verbose)
Basic Usage of :func:`add_argument` Quick Links for add_argument()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ------------------------------
====================== =========================================================== ==========================================================================================================================
**Name or Flags Type** Name Description Values
====================== =========================================================== ==========================================================================================================================
====================== =========================== action_ Specify how an argument should be handled ``'store'``, ``'store_const'``, ``'store_true'``, ``'append'``, ``'append_const'``, ``'count'``, ``'help'``, ``'version'``
Type Example choices_ Limit values to specific set of choices ``['foo', 'bar']``, ``range(1, 10)``, or an object that supports ``in`` operator
====================== =========================== const_ Store a constant value
Positional ``'foo'``
Optional ``'-v'``, ``'--verbose'``
====================== ===========================
**Basic Arguments:**
====================== =========================================================== =========================================================================================================================
Name Description Keywords
====================== =========================================================== =========================================================================================================================
action_ Specifies how an argument should be handled ``'store'``, ``'store_const'``, ``'store_true'``, ``'append'``, ``'append_const'``, ``'count'``, ``'help'``, ``'version'``
default_ Default value used when an argument is not provided default_ Default value used when an argument is not provided
type_ Automatically converts an argument to the given type :class:`int`, :class:`float`, :class:`bool`, ``argparse.FileType('w')``, ``callable function`` dest_ Specify the attribute name in result namespace
help_ Help message of an argument help_ Help message for an argument
====================== =========================================================== ========================================================================================================================= metavar_ Alternate display name for the argument as shown in help
nargs_ Number of times the argument can be used ``N`` (:class:`int`), ``'?'``, ``'*'``, ``'+'``, ``argparse.REMAINDER``
required_ Indicate whether an optional argument is required or not ``True``, ``False``
type_ Automatically convert an argument to the given type :class:`int`, :class:`float`, ``argparse.FileType('w')``, or any callable function
**Advanced Arguments:** ====================== =========================================================== ==========================================================================================================================
====================== =========================================================== =======================================================================================================================
Name Description Keywords
====================== =========================================================== =======================================================================================================================
nargs_ Associates a single action with the number of arguments ``N`` (:class:`int`), ``'?'``, ``'*'``, ``'+'``, ``argparse.REMAINDER``
const_ Stores constant values of names or flags
choices_ A container that lists the possible values ``['foo', 'bar']``, ``range(1, 10)``, Any object that supports ``in`` operator
required_ Indicates if an optional argument is required or not ``True``, ``False``
metavar_ An alternative display name for the argument
dest_ Specifies name of attribute to be used in ``parse_args()``
====================== =========================================================== =======================================================================================================================
Example Example