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I don't understand the difference when hinting Iterable and Sequence . What is the main difference between those two and when to use which? I think set is an Iterable but not Sequence , are there any built-in data type that is Sequence but not Iterable ? def foo(baz: Sequence[float]): ... # What is the difference? def bar(baz: Iterable[float]): ...
I'm having a hard time understanding what typing.Annotated is good for from the documentation and an even harder time finding explanations/examples outside the documentation. In what context would you use Annotated ? Does it depend on third-party libraries?
Now that Python 3.10 has been released, is there any preference when indicating that a parameter or returned value might be optional, i.e., can be None . So what is preferred: Option 1: def f(parameter: Optional[int]) -> Optional[str]: Option 2: def f(parameter: int | None) -> str | None: Also, is there any preference between Type | None and None | Typ
I have a function which validates its argument to accept only values from a given list of valid options. Typing-wise, I reflect this behavior using a Literal type alias, like so: from typing import Literal VALID_ARGUMENTS = ['foo', 'bar'] Argument = Literal['foo', 'bar'] def func(argument: 'Argument') -> None: if argument not in VALID_ARGUMENTS: raise Val
In the Python docs about __future__ , there is a table where it shows that annotations are "optional in" 3.7.0b1 and "mandatory in" 4.0, but I am still able to use annotations in 3.8.2 without importing annotations. Given that, what is the use of it? What do "optional" and "mandatory" here mean? >>> def add_int(a:int, b:int) -> int: ... return a
What's the difference between the following two TypeVar s? from typing import TypeVar, Union class A: pass class B: pass T = TypeVar("T", A, B) T = TypeVar("T", bound=Union[A, B]) I believe that in Python 3.12 this is the difference between these two bounds class Foo[T: (A, B)]: ... class Foo[T: A | B]: ... Here's an example of something I don't get: this pa