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From: Roy Smith <roy@panix.com>
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Date: Fri, 25 Jul 2014 12:28:34 -0400
Subject: ArgumentParser maps dash to underscore in flags, but not positional arguments?
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Xref: csiph.com comp.lang.python:75208

I'm using Python 2.7.3.

It looks like ArgumentParser maps "--foo-bar" to "foo_bar" in the =
argument namespace, but doesn't do the same kind of mapping for =
positional arguments.  Is this intentional?  I can't find in the docs =
where it describes this mapping, but it's certainly convenient, and =
seems wrong that it doesn't do it everywhere.

---------------------------------
from argparse import ArgumentParser

parser =3D ArgumentParser()
parser.add_argument("upload-dir")
parser.add_argument("--file-name")
args =3D parser.parse_args()
print args
---------------------------------

$ python args.py  x
Namespace(file_name=3DNone, upload-dir=3D'x')


---
Roy Smith
roy@panix.com