Passing a tuple as command line argument [duplicate]

问题

This question already has answers here:

converting string to tuple (3 answers)

Closed 4 years ago.

My requirement is to pass a tuple as command line argument like

--data (1,2,3,4)

I tried to use the argparse module, but if I pass like this it is receiving as the string '(1,2,3,4)'. I tried by giving type=tuple for argparse.add_argument, but is of no use here.

Do I have to add a new type class and pass that to type argument of add_argument?

Update

I tried the ast.literal_eval based on answers. Thanks for that. But it is giving spaces in the result as shown below.

(1,2,3,4)
<type 'str'>
(1, 2, 3, 4)
<type 'tuple'>

回答1:

Set nargs of the data argument to nargs="+" (meaning one or more) and type to int, you can then set the arguments like this on the command line:

--data 1 2 3 4

args.data will now be a list of [1, 2, 3, 4].

If you must have a tuple, you can do:

my_tuple = tuple(args.data)

Putting it all together:

parser = argparse.ArgumentParser()
parser.add_argument('--data', nargs='+', type=int)
args = parser.parse_args()
my_tuple = tuple(args.data)

来源：https://stackoverflow.com/questions/33564246/passing-a-tuple-as-command-line-argument