Changeset 391 for python/trunk/Doc/library/getopt.rst

Timestamp:

Mar 19, 2014, 11:31:01 PM (11 years ago)

Author:

dmik

Message:

python: Merge vendor 2.7.6 to trunk.

Location:

python/trunk

Files:

• . (modified) (1 prop)
• Doc/library/getopt.rst (modified) (8 diffs)

python/trunk/Doc/library/getopt.rst

@@ -1 @@
-
-:mod:`getopt` --- Parser for command line options
-=================================================
+:mod:`getopt` --- C-style parser for command line options
+=========================================================
 
 .. module:: getopt
@@ -7 +6 @@
               names.
 
+**Source code:** :source:`Lib/getopt.py`
+
+--------------
+
+.. note::
+   The :mod:`getopt` module is a parser for command line options whose API is
+   designed to be familiar to users of the C :c:func:`getopt` function. Users who
+   are unfamiliar with the C :c:func:`getopt` function or who would like to write
+   less code and get better help and error messages should consider using the
+   :mod:`argparse` module instead.
 
 This module helps scripts to parse the command line arguments in ``sys.argv``.
-It supports the same conventions as the Unix :cfunc:`getopt` function (including
+It supports the same conventions as the Unix :c:func:`getopt` function (including
 the special meanings of arguments of the form '``-``' and '``--``').  Long
 options similar to those supported by GNU software may be used as well via an
 optional third argument.
-
-A more convenient, flexible, and powerful alternative is the
-:mod:`optparse` module.
 
 This module provides two functions and an
@@ -27 +33 @@
    means ``sys.argv[1:]``. *options* is the string of option letters that the
    script wants to recognize, with options that require an argument followed by a
-   colon (``':'``; i.e., the same format that Unix :cfunc:`getopt` uses).
+   colon (``':'``; i.e., the same format that Unix :c:func:`getopt` uses).
 
    .. note::
 
-      Unlike GNU :cfunc:`getopt`, after a non-option argument, all further
+      Unlike GNU :c:func:`getopt`, after a non-option argument, all further
       arguments are considered also non-options. This is similar to the way
       non-GNU Unix systems work.
 
    *long_options*, if specified, must be a list of strings with the names of the
-   long options which should be supported.  The leading ``'-``\ ``-'``
+   long options which should be supported.  The leading ``'--'``
    characters should not be included in the option name.  Long options which
    require an argument should be followed by an equal sign (``'='``).  Optional
@@ -43 +49 @@
    long as they provide a prefix of the option name that matches exactly one of
    the accepted options.  For example, if *long_options* is ``['foo', 'frob']``,
-   the option :option:`--fo` will match as :option:`--foo`, but :option:`--f`
+   the option ``--fo`` will match as ``--foo``, but ``--f``
    will not match uniquely, so :exc:`GetoptError` will be raised.
 
@@ -51 +57 @@
    option-and-value pair returned has the option as its first element, prefixed
    with a hyphen for short options (e.g., ``'-x'``) or two hyphens for long
-   options (e.g., ``'-``\ ``-long-option'``), and the option argument as its
+   options (e.g., ``'--long-option'``), and the option argument as its
    second element, or an empty string if the option has no argument.  The
    options occur in the list in the same order in which they were found, thus
@@ -64 +70 @@
    non-option argument is encountered.
 
-   If the first character of the option string is '+', or if the environment
+   If the first character of the option string is ``'+'``, or if the environment
    variable :envvar:`POSIXLY_CORRECT` is set, then option processing stops as
    soon as a non-option argument is encountered.
@@ -121 +127 @@
        try:
            opts, args = getopt.getopt(sys.argv[1:], "ho:v", ["help", "output="])
-       except getopt.GetoptError, err:
+       except getopt.GetoptError as err:
            # print help information and exit:
            print str(err) # will print something like "option -a not recognized"
@@ -143 +149 @@
        main()
 
+Note that an equivalent command line interface could be produced with less code
+and more informative help and error messages by using the :mod:`argparse` module::
+
+   import argparse
+
+   if __name__ == '__main__':
+       parser = argparse.ArgumentParser()
+       parser.add_argument('-o', '--output')
+       parser.add_argument('-v', dest='verbose', action='store_true')
+       args = parser.parse_args()
+       # ... do something with args.output ...
+       # ... do something with args.verbose ..
 
 .. seealso::
 
-   Module :mod:`optparse`
-      More object-oriented command line option parsing.
+   Module :mod:`argparse`
+      Alternative command line option and argument parsing library.