How to accept lists of multiple elements as command line arguments?

Question

So I have a parser set up like such:

parser.add_argument('-f', '--foo', metavar='foo', type=ast.literal_eval, default=[], help="Foo")

And I need to let users enter multiple values if they so desire:

$ python3 foo.py -f [0x01, 0x56, 0xff] -a blah -b blah ...

But whenever I try more than one value in the list I get an EOF error:

...
File "<unknown>", line 1
[0x01,
     ^
SyntaxError: unexpected EOF while parsing

What's the proper way to set up the parser to handle something like this?

did you try `python3 foo.py -f "[0x01, 0x56, 0xff]" -a blah -b blah ..` instead? — Patrick Artner, Dec 21 '18 at 19:15
The shell splits arguments at spaces. Quote your spaces if you don't want to treat them as separators. — melpomene, Dec 21 '18 at 19:15
@Chris_Rands the problem here is that the shell splits at spaces - I did look further than that-your dupe is better. — Patrick Artner, Dec 21 '18 at 19:23
Look at `sys.argv` to see what the parser has to work with. It's a list of strings as split up by the shell. Your `type` function handles one string at a time. — hpaulj, Dec 21 '18 at 19:38

score 3 · Answer 1 · answered Dec 21 '18 at 19:15

3

Just wrap it in "":

python3 foo.py -f "[0x01, 0x56, 0xff]" -a blah -b blah ...

and then just have foo.py (in this case) parse it.

answered Dec 21 '18 at 19:15

fixatd

1 Answers1