How to use argparse subparsers correctly?

Question

I\'ve been searching through allot of the subparser examples on here and in general but can\'t seem to figure this seemingly simple thing out.

I have two var types o

Answer 1

Subparsers are invoked based on the value of the first positional argument, so your call would look like

python test01.py A a1 -v 61

The "A" triggers the appropriate subparser, which would be defined to allow a positional argument and the -v option.

Because argparse does not otherwise impose any restrictions on the order in which arguments and options may appear, and there is no simple way to modify what arguments/options may appear once parsing has begun (something involving custom actions that modify the parser instance might work), you should consider replacing -t itself:

import argparse

parser = argparse.ArgumentParser()
subparsers = parser.add_subparsers(help='types of A')
parser.add_argument("-v", ...)

a_parser = subparsers.add_parser("A")
b_parser = subparsers.add_parser("B")

a_parser.add_argument("something", choices=['a1', 'a2'])

Since -v is defined for the main parser, it must be specified before the argument that specifies which subparser is used for the remaining arguments.