argparse argument order

flopit picture flopit · Jan 27, 2012 · Viewed 14.4k times · Source

I have a little problem.

I use argparse to parse my arguments, and it's working very well.

To have the args, I do :

p_args = parser.parse_args(argv)
args = dict(p_args._get_kwargs())

But the problem with p_args is that I don't know how to get these arguments ordered by their position in the command line, because it's a dict.

So is there any possibility to have the arguments in a tuple/list/ordered dict by their order in the command line?

Answer

jterrace picture jterrace · Jan 27, 2012

To keep arguments ordered, I use a custom action like this:

import argparse
class CustomAction(argparse.Action):
    def __call__(self, parser, namespace, values, option_string=None):
        if not 'ordered_args' in namespace:
            setattr(namespace, 'ordered_args', [])
        previous = namespace.ordered_args
        previous.append((self.dest, values))
        setattr(namespace, 'ordered_args', previous)
parser = argparse.ArgumentParser()
parser.add_argument('--test1', action=CustomAction)
parser.add_argument('--test2', action=CustomAction)

To use it, for example:

>>> parser.parse_args(['--test2', '2', '--test1', '1'])
Namespace(ordered_args=[('test2', '2'), ('test1', '1')], test1=None, test2=None)