Print an asterisk triangle without for-loops

print-asterisk-triangle.py

#!/usr/bin/env python3
# -*- coding: utf-8 -*-

import argparse
import logging
import os
import sys


def parse_args() -> argparse.Namespace:
    parser: argparse.ArgumentParser = argparse.ArgumentParser()

    parser.add_argument('n', metavar='N', type=int)

    return parser.parse_args()


def asterisk_triangle(remaining_level: int, _current_level: int = 1) -> str:
    res: str = ""

    if remaining_level == 0:
        return res

    if remaining_level < 0:
        raise ValueError('remaining level cannot be less than 0')

    asterisk: str = '*' * (_current_level * 2 - 1)
    space: str = ' ' * (remaining_level - 1)
    res = f'{space}{asterisk}{os.linesep if remaining_level > 1 else ""}'

    return res + asterisk_triangle(remaining_level - 1, _current_level=_current_level + 1)


def main() -> int:
    logging.basicConfig()

    args: argparse.Namespace = parse_args()

    try:
        print(asterisk_triangle(args.n))
    except ValueError as e:
        logging.exception(e)

    return os.EX_OK


if __name__ == '__main__':
    sys.exit(main())