is the Option instance that's calling the callback
opt_str
is the option string seen on the command-line that's triggering the
callback. (If an abbreviated long option was used, opt_str will
be the full, canonical option string--e.g. if the user puts
"-foo" on the command-line as an abbreviation for
"-foobar", then opt_str will be "-foobar".)
value
is the argument to this option seen on the command-line. optparse will
only expect an argument if type is set; the type of value
will be the type implied by the option's type. If type for this
option is None (no argument expected), then value will be
None. If nargs > 1, value will be a tuple of values of
the appropriate type.
parser
is the OptionParser instance driving the whole thing, mainly
useful because you can access some other interesting data through
its instance attributes:
parser.largs
the current list of leftover arguments, ie. arguments that have
been consumed but are neither options nor option arguments.
Feel free to modify parser.largs, e.g. by adding more
arguments to it. (This list will become args, the second
return value of parse_args().)
parser.rargs
the current list of remaining arguments, ie. with opt_str and
value (if applicable) removed, and only the arguments
following them still there. Feel free to modify
parser.rargs, e.g. by consuming more arguments.
parser.values
the object where option values are by default stored (an
instance of optparse.OptionValues). This lets callbacks use the
same mechanism as the rest of optparse for storing option values;
you don't need to mess around with globals or closures. You can
also access or modify the value(s) of any options already
encountered on the command-line.
args
is a tuple of arbitrary positional arguments supplied via the
callback_args option attribute.
kwargs
is a dictionary of arbitrary keyword arguments supplied via
callback_kwargs.
