What are some advanced typing examples in Python?

What are some advanced typing examples in Python?

In Python, advanced typing includes features like TypeVar, Generic, and Union. Would you like to see examples of these?

Yes, please provide an example using TypeVar.

Sure! Here's an example using TypeVar:

from typing import TypeVar, List

T = TypeVar('T')

def get_first_element(elements: List[T]) -> T:
    return elements[0]

This function returns the first element of a list, regardless of its type.

That's great! Can you show me how to use Union?

Absolutely! Here's how you can use Union:

from typing import Union

def process_value(value: Union[int, str]) -> str:
    return f'Processed value: {value}'

This function can accept either an integer or a string.

Thanks! What about using Generics?

Generics allow you to define a class or function that can operate on different types. Here's an example:

from typing import Generic, TypeVar

T = TypeVar('T')

class Box(Generic[T]):
    def __init__(self, content: T):
        self.content = content

    def get_content(self) -> T:
        return self.content

This Box class can hold any type of content.