multiple optional positional arguments
Thomas Moschny
[[foo] bar]"?
The idea is that the command can be called with zero, one, or two
arguments, and if called with one arg that arg should be assigned to
bar, not to foo. Maybe what I'm looking for is sort of a non-greedy
optional positional arg, a-la nargs="??".
akira
>>> import argparse
>>> p = argparse.ArgumentParser(prog='PROG')
>>> p.add_argument('bar', nargs='?')
>>> p.add_argument('foo', nargs='?')
>>> p.parse_args([]) # zero
Namespace(bar=None, foo=None)
>>> p.parse_args(['1']) # one
Namespace(bar='1', foo=None)
>>> p.parse_args(['1', '2']) # two
Namespace(bar='1', foo='2')
>>> p.print_usage()
usage: PROG [-h] [bar] [foo]
Thomas Moschny
> On 01/05/2011 07:32 PM, Thomas Moschny wrote:
>>
>> Is it possible to specify a parser for this commandline: "command
>> [[foo] bar]"?
>>
>> The idea is that the command can be called with zero, one, or two
>> arguments, and if called with one arg that arg should be assigned to
>> bar, not to foo. Maybe what I'm looking for is sort of a non-greedy
>> optional positional arg, a-la nargs="??".
>>
> It seems equivalent to "command [bar] [foo]"
Sure, but that wasn't the question. The ordering of foo and bar in my
case is important (and btw, it is equivalent to "command [bar
[foo]]").
Steven Bethard
No, there's currently no way of getting this behavior. Your best bet
is probably to specify nargs='?' twice, and then do some post-hoc
processing to decide which is which, e.g.:
if args.bar is None:
args.bar = args.foo
args.foo = None
Steve
--
Where did you get that preposterous hypothesis?
Did Steve tell you that?
--- The Hiphopopotamus