6.6. Type Annotation TypedDict¶
Since Python 3.8:
PEP 589 -- TypedDict: Type Hints for Dictionaries with a Fixed Set of Keys
6.6.1. SetUp¶
>>> from typing import TypedDict
6.6.2. Definition¶
>>> class Astronaut(TypedDict):
... firstname: str
... lastname: str
... age: int | float
6.6.3. Example¶
>>> def hello_astronaut(astronaut: Astronaut):
... result = f'Hello {astronaut["firstname"]} {astronaut["lastname"]}'
>>> mark: Astronaut = {'firstname': 'Mark', 'lastname': 'Watney', 'age': 40}
>>> hello_astronaut(mark) # ok
>>>
>>> mark: Astronaut = {'firstname': 'Mark', 'lastname': 'Watney'}
>>> hello_astronaut(mark) # error: missing `age`
>>>
>>> mark: Astronaut = {'firstname': 'Mark'}
>>> hello_astronaut(mark) # error: missing `lastname` and `age`
>>>
>>> mark = Astronaut(firstname='Mark', lastname='Watney', age=40)
>>> hello_astronaut(mark) # ok
>>>
>>> mark = Astronaut(firstname='Mark', lastname='Watney')
>>> hello_astronaut(mark) # error: missing `age`
>>>
>>> mark = Astronaut(firstname='Mark')
>>> hello_astronaut(mark) # error: missing `lastname`
>>>
>>> iris = {'genus': 'Iris', 'species': 'Setosa'}
>>> hello_astronaut(iris) # error: not an astronaut
6.6.4. Typed Dict¶
Since Python 3.8: PEP 589 -- TypedDict: Type Hints for Dictionaries with a Fixed Set of Keys
>>> from typing import TypedDict
>>> class Astronaut(TypedDict):
... firstname: str
... lastname: str
... age: int | float
...
...
>>> def hello_astronaut(astronaut: Astronaut):
... result = f'Hello {astronaut["firstname"]} {astronaut["lastname"]}'
...
...
>>> mark: Astronaut = {'firstname': 'Mark', 'lastname': 'Watney', 'age': 40}
>>> hello_astronaut(mark) # ok
>>>
>>> mark: Astronaut = {'firstname': 'Mark', 'lastname': 'Watney'}
>>> hello_astronaut(mark) # error: missing `age`
>>>
>>> mark: Astronaut = {'firstname': 'Mark'}
>>> hello_astronaut(mark) # error: missing `lastname` and `age`
>>>
>>> mark = Astronaut(firstname='Mark', lastname='Watney', age=40)
>>> hello_astronaut(mark) # ok
>>>
>>> mark = Astronaut(firstname='Mark', lastname='Watney')
>>> hello_astronaut(mark) # error: missing `age`
>>>
>>> mark = Astronaut(firstname='Mark')
>>> hello_astronaut(mark) # error: missing `lastname`
>>>
>>> iris = {'genus': 'Iris', 'species': 'Setosa'}
>>> hello_astronaut(iris) # error: not an astronaut
6.6.5. Future¶
Since Python 3.11 PEP 655 -- Marking individual TypedDict items as required or potentially-missing
>>>
... from typing import Required, NotRequired
...
...
... class Astronaut(TypedDict):
... firstname: Required[str]
... lastname: Required[str]
... age: NotRequired[int|float]
...
...
... def hello_astronaut(astronaut: Astronaut):
... result = f'Hello {astronaut["firstname"]} {astronaut["lastname"]}')
...
...
... mark: Astronaut = {'firstname': 'Mark', 'lastname': 'Watney', 'age': 40}
... hello_astronaut(mark) # ok
...
... mark: Astronaut = {'firstname': 'Mark', 'lastname': 'Watney'}
... hello_astronaut(mark) # ok
...
... mark: Astronaut = {'firstname': 'Mark'}
... hello_astronaut(mark) # error: missing `lastname`
...
... mark = Astronaut(firstname='Mark', lastname='Watney', age=40)
... hello_astronaut(mark) # ok
...
... mark = Astronaut(firstname='Mark', lastname='Watney')
... hello_astronaut(mark) # ok
...
... mark = Astronaut(firstname='Mark')
... hello_astronaut(mark) # error: missing `lastname`
...
... iris = {'genus': 'Iris', 'species': 'Setosa'}
... hello_astronaut(iris) # error: not an astronaut
#%%
- class Person(NamedTuple):
firstname: str lastname: str
- def say_hello(person: Person):
print(f'Witaj {person.firstname} {person.lastname}')
osoba = Person(firstname='Mark', lastname='Watney') say_hello(osoba)
#%%
- class Point(TypedDict):
x: int y: int z: int
point = Point(x=1, y=2, z=3) point: Point = {'x':1, 'y':2, 'z':3} point: Point = {'x':1, 'y':2, 'z':3.0} # z jest float, a miał być int point: Point = {'x':1, 'y':2} # brakuje z
- class Point(TypedDict):
x: int y: int z: int | None
point: Point = {'x':1, 'y':2, 'z':None}
- class Point(TypedDict):
x: int y: int z: NotRequired[int]
point: Point = {'x':1, 'y':2, 'z':3} # ok point: Point = {'x':1, 'y':2, 'z':3.0} # nie ok point: Point = {'x':1, 'y':2, 'z':None} # nie ok point: Point = {'x':1, 'y':2} # ok
- class Point(TypedDict):
x: Required[int] y: Required[int] z: NotRequired[int]
- class GeographicCoordinate(NamedTuple):
latitude: float longitude: float
- locations: list[GeographicCoordinate] = [
(25.91375, -60.15503), (-11.01983, -166.48477), (-11.01983, -166.48477)]
- locations: list[GeographicCoordinate] = [
GeographicCoordinate(25.91375, -60.15503), GeographicCoordinate(-11.01983, -166.48477), GeographicCoordinate(-11.01983, -166.48477)]
- locations: list[GeographicCoordinate] = [
GeographicCoordinate(latitude=25.91375, longitude=-60.15503), GeographicCoordinate(latitude=-11.01983, longitude=-166.48477), GeographicCoordinate(latitude=-11.01983, longitude=-166.48477)]
6.6.6. Further Reading¶
More information in Type Annotations
More information in CI/CD Type Checking