Get dest for all args in argparser

Question

I would like to get the dest values for all the arguments defined for the parser. I.e. in the case of:

parser = argparse.ArgumentParser()
parser.add_argument('arg1')
parser.add_argument('arg2')
parser.add_argument('arg3')
parser.add_argument('arg4')

I would like to return ['arg1', 'arg2', 'arg3', 'arg4'].

parser.parse_args() takes stuff from sys.argv which is not what I'm looking for. How can I achieve this?

Answer 1

Though you don't typically need it, add_argument returns an instance of the Action subclass used to implement the argument. Among other things, these objects have a dest attribute containing the string you want.

For example,

import argparse

parser = argparse.ArgumentParser()
a1 = parser.add_argument('arg1')
a2 = parser.add_argument('arg2')
a3 = parser.add_argument('arg3')
a4 = parser.add_argument('arg4')
     
destinations = [x.dest for x in [a1, a2, a3, a4]])

parser._actions contains a list of all arguments defined for the parser, including things like --help, so that may also be of use.