在列表理解中编写长 if 语句的 Pythonic 方式

Question

I'm beginner in python and hope you help me find way to write if statement correctly. This is code i have:

target_dir = Path(__file__).resolve().parents[1]
nav_files = [
    x
    for x in target_dir.rglob('conf.yaml')
    if '.'.join(str(x.parent).replace(str(target_dir), '').lstrip('/').split('/')[:2]) in settings.MODULES
]

You may see unacceptably long if statement. As i understand there are 2 ways to resolve this:

1. Separate nav_files preparation and use some for blocks
2. Separate if statement by linebreaks(if it's possible)

What is the best practice? Thanks!

Answer 1

You can use a backslash before each newline to combine several physical lines as one logical line. A more common practice in Python is to wrap lines inside parentheses; then Python knows the statement has ho continue, and you don't need a backslash.

nav_files = [
    x for x in target_dir.rglob('conf.yaml')
    if '.'.join(
        str(x.parent).replace(
            str(target_dir), '').lstrip(
            '/').split('/')[:2]) in settings.MODULES
]