Message186110
| Author |
paul.j3 |
| Recipients |
bethard, eric.smith, gcbirzan, jeffknupp, kalt, paul.j3, python-dev, r.david.murray, wt |
| Date |
2013年04月05日.21:59:03 |
| SpamBayes Score |
-1.0 |
| Marked as misclassified |
Yes |
| Message-id |
<1365199143.92.0.947817397442.issue13922@psf.upfronthosting.co.za> |
| In-reply-to |
| Content |
There's another 'feature' to the patch proposed here. It only deletes the first '--' in the list of strings passed to '_get_values' for a particular action.
parser = argparse.ArgumentParser()
parser.add_argument('foo')
parser.add_argument('bar', nargs='*')
print(parser.parse_args('-- 1 -- 2 3 4'.split(' ')))
# Namespace(bar=['2', '3', '4'], foo='1')
'_get_values' first gets ('foo',['--','1']), then ('bar',['--','2','3','4'])
print(parser.parse_args('-- -- 1 -- 2 -- 3 4'.split(' ')))
# with this '1st only' change
# Namespace(bar=['1', '2', '--', '3', '4'], foo='--')
# without it, deleting all '--'; note foo is empty
# Namespace(bar=['1', '2', '3', '4'], foo=[])
And to confuse things a bit more:
print(parser.parse_args('1 -- 2 3 4'.split(' ')))
# Namespace(bar=['2', '3', '4'], foo='1')
passes ['1','--'] with 'foo'
If 'bar' nargs='...', bar gets all of the '--' (with or without this patch).
The handling of '--' is complex because it is used in one place to mean, 'everything else is an argument', effectively adding '-AA...' to the arg_strings_pattern. It also matches with the nargs_pattern (e.g. '(-*A-*)...'). And then it may or may not be removed in _get_values(). |
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