How to get available flags out of an ArgumentParser object?

问题

I'm using the argparse module for this python project. I'm looking to get the available flags out of an ArgumentParser object before calling parse_args(). Anyone have any ideas?

回答1:

Got this from the source code of add_argument():

>>> import argparse
>>> parser = argparse.ArgumentParser()
>>> parser.add_argument('-v', '--verbosity', help='more debug info', action='store_true')
_StoreTrueAction(option_strings=['-v', '--verbosity'], dest='verbosity', nargs=0, const=True, default=False, type=None, choices=None, help='more debug info', metavar=None)
>>> parser._option_string_actions.keys()
['-v', '-h', '--verbosity', '--help']
>>> 

回答2:

I was trying to solve this the other day and I never got a satisfactory answer other than the following on from what @vvoody did.

In [117]: map(lambda x : x.dest,parser._actions)
Out[117]: ['help', 'verbosity']

The benefit is that it removes all the alias -v == --verbosity etc. BUT if you change dest for --verbosity e.g dest='loud' then it returns loud which may or may not be an issue.

Seems an obvious thing for argsparse to provide out of the box.

来源：https://stackoverflow.com/questions/14913855/how-to-get-available-flags-out-of-an-argumentparser-object