Learning second part of argparse to taste the DRY (don’t repeat yourself) principle [1] and simplify the example.
File is arg_parse.py
"""
arg_parse.py
"""
import argparse
def parse_arguments():
parser = argparse.ArgumentParser(description='Argument get parse via --commands')
parser.add_argument("-x", metavar='value', required=True, help='first value to parse')
parser.add_argument("-y", metavar='value', required=True, help='second value to parse')
args = parser.parse_args()
return args
def main():
print('first value is ', args.x, sep='')
print('second value is ', args.y, sep='')
if __name__ == '__main__':
args = parse_arguments()
main()
Previous file can be executed as follows with the results
L:\home\butir\code\0\07\1>py arg_parse.py -h
usage: arg_parse.py [-h] -x value -y value
Argument get parse via --commands
optional arguments:
-h, --help show this help message and exit
-x value first value to parse
-y value second value to parse
to see the help,
L:\home\butir\code\0\07\1>py arg_parse.py
usage: arg_parse.py [-h] -x value -y value
arg_parse.py: error: the following arguments are required: -x, -y
L:\home\butir\code\0\07\1>py arg_parse.py -y
usage: arg_parse.py [-h] -x value -y value
arg_parse.py: error: argument -y: expected one argument
L:\home\butir\code\0\07\1>py arg_parse.py -y 2.5
usage: arg_parse.py [-h] -x value -y value
arg_parse.py: error: the following arguments are required: -x
L:\home\butir\code\0\07\1>py arg_parse.py -y 2.5 -x
usage: arg_parse.py [-h] -x value -y value
arg_parse.py: error: argument -x: expected one argument
to test whether all two arguments are provided, and
L:\home\butir\code\0\07\1>py arg_parse.py -y 2.5 -x -220
first value is -220
second value is 2.5
to get the intended result. See documentation [2] for further information.
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