Sort/short-circuit getopt flags in python

Question

I have a simple python command-line application I'm currently expanding. It currently supports a couple command-line arguments:

try:
    opts, args = getopt.getopt(sys.argv[1:], 'b:h',
                               ['battle=', 'help'])
except getopt.GetoptError:
    usage()
    raise

# Parse opts/args.
for opt, arg in opts:
    if opt in ('-h', '--help'):
        usage()
    elif opt in ('-b', '--battle'):
        battle = True

I'm going to have to add LOTS of additional command-line arguments. The way I'll be implementing it, I'll have to keep track of an "is set" flag for every flag the user could set.

There are some cases where I would like to "short circuit" my parser, such as, if the user ran it with both the -x, -y, and -z flags, to tell the parser to skip all remaining parsing operations, and just run a specific function. However, this would would an is x,y,z set check for each of those options.

1. Is there a "pythonic" way to simplify parsing by allowing me to "short circuit" certain parsing operations?
2. Is it possible to guarantee I'll parse flags/opts in a specific order by sorting opt and arg?

Answer 1

Is using getopt a hard requirement? Arguably the more 'pythonic' approach is to use argparse, a simpler, more high-level module. In that case you can define your argparser as:

parser = argparse.ArgumentParser()
parser.add_argument("-x", ...)
parser.add_argument("-y", ...)
parser.add_argument("-z", ...)

args = parser.parse_args()
if args.x and args.y and args.z:
    short_circuit()

For your second question, I think that using argparse will remove the need to worry about parsing order, since you call each arg by name from the args object.