ruk·si

🐍 Python
Naming

Updated at 2018-06-03 02:22

Be consistent with your naming. Always consider following naming guidelines of libraries and frameworks you use. Here is naming rules I use in my own projects.

variables_are_in_snake_case
functions_are_in_snake_case()

my_class.public_instance_variables_are_in_snake_case
my_class.public_methods_are_in_snake_case()

_underscore_communicates_that_it_should_not_be_used_outside_of_the_module_py

ClassesAreInPascalCase
TypesAreInPascalCase
AcronymsAreInAllCapsLOL
HTTPServerError # (not HttpServerError)

CONSTANTS_ARE_IN_UPPER_SNAKE_CASE

"Dunder" means "double-underscore" when talking or reading about Python. This refers to Python methods with special meaning that start and end with __.

class A:
    def __init__(self) -> None:
        # "dunder init"
        pass

Avoid trailing underscores. Some people use trailing underscore to avoid conflicts with Python keywords. Avoid using those, find a synonym to replace the word.

# bad
my_object.add_style(master, class_='ClassName')

# good
my_object.add_style(master, name='ClassName')
my_object.add_style(master, genre='ClassName')
my_object.add_style(master, style='ClassName')
my_object.add_style(master, styleClass='ClassName')
my_object.add_style(master, className='ClassName')

Use a single underscore _ for unused values.

for _ in range(5):
    print('Hello, World.')

_, age = get_name_and_age()

Never introduce new symbols with double leading and trailing underscores. Double leading and trailing underscores mean "magic".

__init__
__import__

All file and directory names are in snake_case. Even files containing just a single class named in PascalCase.

models.py
urls.py
class SendUpdateView: => send_update_view.py
class HTTPResponse:   => http_response.py

Thus modules names are in snake_case. Module name may be for the collection of loose functionality or a single class. Module name is the same as the file name.

module_name.py

Thus packages names are in snake_case. Underscores are to be avoided, but they are grudgingly allowed.

# good
superpackage/

# if you must...
super_package/

Sources