- Union
Either this or that type (Union)
- Python 3.10+
examples/python-types-at-pyweb-2025-01/pipe.py
def my_exit(code: str | int): print(type(code).__name__) my_exit(3) my_exit("problem") my_exit(3.14)
$ python union.py int str float $ mypy pipe.py pipe.py:6:9: error: Argument 1 to "my_exit" has incompatible type "float"; expected "str | int" [arg-type] Found 1 error in 1 file (checked 1 source file)