Python

mypy Commands

Optional static type checker for Python. Catch type errors before runtime by analyzing type annotations in your code.

9 commands

Pro Tips

Start with '--strict' mode for new projects to enforce full type coverage.

Use 'py.typed' marker file to indicate your package is typed.

Configure per-module overrides in mypy.ini for gradual typing adoption.

Common Mistakes

Third-party packages may need type stubs - install types-* packages.

Use '--ignore-missing-imports' carefully - it hides real import errors.

Commands

Check file

$ mypy script.py

Type check a single file.

Check directory

$ mypy src/

Type check all files in a directory.

Strict mode

$ mypy --strict src/

Enable all strict type checking options.

Ignore missing imports

$ mypy --ignore-missing-imports src/

Suppress errors for untyped dependencies.

Disallow untyped defs

$ mypy --disallow-untyped-defs src/

Error on functions without type annotations.

Show error codes

$ mypy --show-error-codes src/

Display error codes for easier suppression.

Pretty output

$ mypy --pretty src/

Show errors with context and formatting.

Check specific version

$ mypy --python-version 3.10 src/

Type check against specific Python version.

No incremental

$ mypy --no-incremental src/

Run fresh check without using cache.