Argparse不会解析我在命令行中传递的任何参数

Question

I'm trying to run my program in Terminal:

py program.py -t

and it's not setting the boolean to False. From what I can see, all of my code looks correct.

isTitle = True

a = argparse.ArgumentParser(prog='program.py', usage='%(prog) [options]', description='The fooiest of bar')
a.add_argument('-t', '--title', action='store_const', const=False, dest='isTitle', help='show title')
r = a.parse_args()

I have a statement after the parse_args that prints the isTitle boolean to verify it's been set, and it always returns True. Do you guys have any recommendations? I can add more code/diagnostic statements if need be. Thank you!

Answer 1

dest='isTitle' doesn't mean that a variable named isTitle will be changed, it means the value will be stored in r.isTitle , ie in the object the parse_args call returns. It would be madness for argparse to modify any variables in the global scope.

What you want is simply:

a.add_argument('-t', '--title', action='store_true', dest='isTitle', help='show title')
r = a.parse_args()
print(r.isTitle)