How to convert ArgumentParser code to Mojo?

[huiliukeith-mineral]

I am trying to convert code like this to Mojo

    parser = argparse.ArgumentParser()
    parser.add_argument('--weights', type=str, default='yolo7.pt', help='initial weights path')
    parser.add_argument('--cfg', type=str, default='', help='model.yaml path')
    parser.add_argument('--data', type=str, default='data/coco.yaml', help='data.yaml path')

and what I did

let argparse = Python.import_module("argparse")
let parser = argparse.ArgumentParser()
    parser.add_argument('--weights', type=str, default='yolo7.pt', help='initial weights path')
    parser.add_argument('--cfg', type=str, default='', help='model.yaml path')
    parser.add_argument('--data', type=str, default='data/coco.yaml', help='data.yaml path')

and I got

yolov7/train.mojo:566:43: error: use of unknown declaration 'str', 'fn' declarations require explicit variable declarations"

[pu2is]

extactly same exception :(

[pu2is]

I am trying to convert code like this to Mojo

    parser = argparse.ArgumentParser()
    parser.add_argument('--weights', type=str, default='yolo7.pt', help='initial weights path')
    parser.add_argument('--cfg', type=str, default='', help='model.yaml path')
    parser.add_argument('--data', type=str, default='data/coco.yaml', help='data.yaml path')

and what I did

let argparse = Python.import_module("argparse")
let parser = argparse.ArgumentParser()
    parser.add_argument('--weights', type=str, default='yolo7.pt', help='initial weights path')
    parser.add_argument('--cfg', type=str, default='', help='model.yaml path')
    parser.add_argument('--data', type=str, default='data/coco.yaml', help='data.yaml path')

and I got

yolov7/train.mojo:566:43: error: use of unknown declaration 'str', 'fn' declarations require explicit variable declarations"

from python import Python

fn main() raises:
    let argparse = Python.import_module("argparse")
    let parser = argparse.ArgumentParser()
    parser.description = "your description here"
    let example_arg = parser.add_argument("-d", "--database")
    example_arg.require = True
    example_arg.help = "help text"
    print(parser)
    print(example_arg)

the output is

ArgumentParser(prog='', usage=None, description='your description here', ...)
_StoreAction(option_strings=['-d', '--database'], dest='database', nargs=None, ..., help='help text')

but if i append following code there is exception:

...
print(...)
let args = parser.parse_args()

execution with: mojo main.mojo -d foo
got exception:

usage: [-h] -d DATABASE
: error:  the following arguments are required: -d/--database
unhandled exception caught during execution: 2
mojo: error: execution exited with a non-zero result: 1

then i changed the example_arg.required = False and add example_arg.default = "foo_1"
the exception is no longer exists.
if i print the args.database the output is foo_1, which is correct.

the problem could be: how to set required var through a command line

[gryznar]

Unknown declaration str comes from the fact that Mojo does not support Python's str yet. Try to use str from builtins:

let builtins = Python.import_module("builtins")
parser.add_argument('--weights', type=builtins.str, default='yolo7.pt', help='initial weights path')