argparse optional subparser (for --version)

Question

I have the following code (using Python 2.7):

# shared command line options, like --version or --verbose
parser_shared = argparse.ArgumentParser(add_help=Fal         


        

Answer 1

Yeah, I just checked svn, which is used as an object example in the add_subparsers() documentation, and it only supports '--version' on the main command:

python zacharyyoung$ svn log --version
Subcommand 'log' doesn't accept option '--version'
Type 'svn help log' for usage.

Still:

# create common parser
parent_parser = argparse.ArgumentParser('parent', add_help=False)
parent_parser.add_argument('--version', action='version', version='%(prog)s 2.0')

# create the top-level parser
parser = argparse.ArgumentParser(parents=[parent_parser])
subparsers = parser.add_subparsers()

# create the parser for the "foo" command
parser_foo = subparsers.add_parser('foo', parents=[parent_parser])

Which yields:

python zacharyyoung$ ./arg-test.py --version
arg-test.py 2.0
python zacharyyoung$ ./arg-test.py foo --version
arg-test.py foo 2.0