Python typing: Difference between revisions
From wikinotes
Line 9: | Line 9: | ||
class Project: | class Project: | ||
def ex_param_w_return(user: User) -> Bool | def ex_param_w_return(user: User) -> Bool | ||
def ex_type_w_default(active: bool=False) -> None: | def ex_type_w_default(active: bool=False) -> None: | ||
def ex_no_return() -> None: | def ex_no_return() -> None: | ||
def ex_generics(data: List[Dict]): | def ex_generics(data: List[Dict]): | ||
def ex_optional() -> Optional[str]: # nullable type | def ex_optional() -> Optional[str]: # nullable type | ||
def ex_type_or_other_type(id: Union[str, int]) -> None: | def ex_type_or_other_type(id: Union[str, int]) -> None: | ||
</source> | </source> | ||
</blockquote><!-- Example --> | </blockquote><!-- Example --> |
Revision as of 15:10, 3 April 2022
Type annotations in python.
Example
from typing import Dict, List, Tuple from typing import Optional, Union class Project: def ex_param_w_return(user: User) -> Bool def ex_type_w_default(active: bool=False) -> None: def ex_no_return() -> None: def ex_generics(data: List[Dict]): def ex_optional() -> Optional[str]: # nullable type def ex_type_or_other_type(id: Union[str, int]) -> None:
Common Types
dates/times
import datetime def foo() -> datetime.datetime: return datetime.datetime.now() def foo() -> datetime.date: return datetime.date.today()open file objects
from typing import IO # either bytes/str def foo() -> IO: return open('foo.txt', 'r') def foo() -> IO[bytes]: return open('foo.txt', 'rb') def foo() -> IO[str]: return open('foo.txt', 'r')context managers
@contextlib.contextmanager def foo() -> Iterator[str]: print('foo') yield 'bar' print('baz')