14.3.3.1 Creating the parser
The first step in using optparse is to create an OptionParser instance:
parser = OptionParser(...)
The OptionParser constructor has no required arguments, but a number of
optional keyword arguments. You should always pass them as keyword
arguments, i.e. do not rely on the order in which the arguments are
declared.
usage (default: "%prog [options]" )
- The usage summary to print when your program is run incorrectly or
with a help option. When optparse prints the usage string, it expands
%prog to os.path.basename(sys.argv[0]) (or to prog if
you passed that keyword argument). To suppress a usage message,
pass the special value optparse.SUPPRESS_USAGE .
option_list (default: [] )
- A list of Option objects to populate the parser with. The options
in
option_list are added after any options in
standard_option_list (a class attribute that may be set by
OptionParser subclasses), but before any version or help options.
Deprecated; use add_option() after creating the parser instead.
option_class (default: optparse.Option)
- Class to use when adding options to the parser in add_option().
version (default: None )
- A version string to print when the user supplies a version option.
If you supply a true value for
version , optparse automatically adds
a version option with the single option string --version. The
substring "%prog" is expanded the same as for usage .
conflict_handler (default: "error" )
- Specifies what to do when options with conflicting option strings
are added to the parser; see section 14.3.3, Conflicts between options.
description (default: None )
- A paragraph of text giving a brief overview of your program. optparse
reformats this paragraph to fit the current terminal width and
prints it when the user requests help (after
usage , but before
the list of options).
formatter (default: a new IndentedHelpFormatter)
- An instance of optparse.HelpFormatter that will be used for
printing help text. optparse provides two concrete classes for this
purpose: IndentedHelpFormatter and TitledHelpFormatter.
add_help_option (default: True )
- If true, optparse will add a help option (with option strings
"-h"
and --help) to the parser.
prog
- The string to use when expanding
"%prog" in usage and
version instead of os.path.basename(sys.argv[0]) .
Release 2.5.2, documentation updated on 21st February, 2008.
See About this document... for information on suggesting changes.
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