Skip to main content

Replace `Optional[T]` by `Union[T, None]`! 🎉

Project description


Package version

This codemod replaces typing.Optional[T] by typing.Union[T, None] in the codebase.


This tool was inspired by a tweet from Sebastián Ramírez (as you see below), and a conversation between us.


As the tweet says, we have two reasons for doing this:

  1. It's more explicit to write Union[str, None] than Optional[str]. Mainly because Optional[str] doesn't mean that the attribute is optional. It only means that it accepts None as a possible value.
  2. On Python 3.10+ you can type annotate as str | None instead of the above two. Which is more similar to Union[str, None] than Optional[str].


pip install no-optional


Run the following on the repository you want to format:

python -m no_optional <files>

You can also use the pre-commit. Add the following to your .pre-commit-config.yaml file:

  - repo:
    rev: 0.4.0
      - id: no_optional


This project is licensed under the terms of the MIT license.

Project details

Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distributions

No source distribution files available for this release.See tutorial on generating distribution archives.

Built Distribution

no_optional-0.4.0-py3-none-any.whl (6.8 kB view hashes)

Uploaded Python 3

Supported by

AWS AWS Cloud computing and Security Sponsor Datadog Datadog Monitoring Fastly Fastly CDN Google Google Download Analytics Microsoft Microsoft PSF Sponsor Pingdom Pingdom Monitoring Sentry Sentry Error logging StatusPage StatusPage Status page