How to specify "nullable" return type with type hints

How to Specify "Nullable" Return Type with Type Hints 😕🔍

Are you in a pickle 🥒 and wondering how to specify the return type for something that can be None? Have no fear, because we've got you covered! 😎 In this blog post, we'll address this common issue and provide you with easy solutions to solve it. So let's dive right in! 🏊‍♀️💥

The Dilemma 🤔

Imagine you have a function like this:

def get_some_date(some_argument: int=None) -> %datetime_or_None%:
    if some_argument is not None and some_argument == 1:
        return datetime.utcnow()
    else:
        return None

You want to use type hints to specify that the return type of this function can be either datetime or None. But how do you do that? 🤷‍♂️

The Solution 💡

To indicate that a return type can be None, you can use the typing.Optional type hint. It's like saying "this type, or None". Problem solved! 🎉

Here's how you can modify your function to specify a nullable return type:

from typing import Optional

def get_some_date(some_argument: int=None) -> Optional[datetime]:
    if some_argument is not None and some_argument == 1:
        return datetime.utcnow()
    else:
        return None

By using Optional[datetime], you're saying that the return type can be either a datetime object or None. Simple, right? 😊

Call to Action ✨📢

Now that you know how to specify a "nullable" return type with type hints, go ahead and give it a try in your own code! Don't be afraid to embrace the power of type hints to make your code more readable and maintainable. And remember, coding is all about learning and exploring, so keep on coding! 🚀🔥

If you found this blog post helpful, feel free to share it with your fellow developer friends. They might be facing the same issue and will appreciate your generosity in sharing knowledge! 🤝🌎

Got any questions or suggestions? Leave a comment below ⬇️ or reach out to us on Twitter 🐦. We'd love to hear from you and continue the conversation! Let's keep making the coding world a better place! 💪💻

Happy coding! 💙

Remember to ALWAYS help people and choose the RIGHT EMOJIS while writing your texts 🥳🤩.