cpython/Doc/library/packaging.fancy_getopt.rst

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:mod:`packaging.fancy_getopt` --- Wrapper around the getopt module
==================================================================
.. module:: packaging.fancy_getopt
:synopsis: Additional getopt functionality.
.. warning::
This module is deprecated and will be replaced with :mod:`optparse`.
This module provides a wrapper around the standard :mod:`getopt` module that
provides the following additional features:
* short and long options are tied together
* options have help strings, so :func:`fancy_getopt` could potentially create a
complete usage summary
* options set attributes of a passed-in object
* boolean options can have "negative aliases" --- e.g. if :option:`--quiet` is
the "negative alias" of :option:`--verbose`, then :option:`--quiet` on the
command line sets *verbose* to false.
.. function:: fancy_getopt(options, negative_opt, object, args)
Wrapper function. *options* is a list of ``(long_option, short_option,
help_string)`` 3-tuples as described in the constructor for
:class:`FancyGetopt`. *negative_opt* should be a dictionary mapping option names
to option names, both the key and value should be in the *options* list.
*object* is an object which will be used to store values (see the :meth:`getopt`
method of the :class:`FancyGetopt` class). *args* is the argument list. Will use
``sys.argv[1:]`` if you pass ``None`` as *args*.
.. class:: FancyGetopt(option_table=None)
The option_table is a list of 3-tuples: ``(long_option, short_option,
help_string)``
If an option takes an argument, its *long_option* should have ``'='`` appended;
*short_option* should just be a single character, no ``':'`` in any case.
*short_option* should be ``None`` if a *long_option* doesn't have a
corresponding *short_option*. All option tuples must have long options.
The :class:`FancyGetopt` class provides the following methods:
.. method:: FancyGetopt.getopt(args=None, object=None)
Parse command-line options in args. Store as attributes on *object*.
If *args* is ``None`` or not supplied, uses ``sys.argv[1:]``. If *object* is
``None`` or not supplied, creates a new :class:`OptionDummy` instance, stores
option values there, and returns a tuple ``(args, object)``. If *object* is
supplied, it is modified in place and :func:`getopt` just returns *args*; in
both cases, the returned *args* is a modified copy of the passed-in *args* list,
which is left untouched.
.. TODO and args returned are?
.. method:: FancyGetopt.get_option_order()
Returns the list of ``(option, value)`` tuples processed by the previous run of
:meth:`getopt` Raises :exc:`RuntimeError` if :meth:`getopt` hasn't been called
yet.
.. method:: FancyGetopt.generate_help(header=None)
Generate help text (a list of strings, one per suggested line of output) from
the option table for this :class:`FancyGetopt` object.
If supplied, prints the supplied *header* at the top of the help.