What are type hints in Python and can you give me some examples?

What are type hints in Python and can you give me some examples?

Type hints in Python are a way to indicate the expected data types of variables, function parameters, and return values. For example, you can use def add(a: int, b: int) -> int: to specify that both a and b should be integers and the function returns an integer.

Can you show me more examples of type hints?

Sure! Here's another example: def greet(name: str) -> str: indicates that name should be a string and the function returns a string. You can also use lists, like def process_items(items: List[str]) -> None: to specify a list of strings.

What if I want to use type hints with optional values?

You can use Optional from the typing module. For example, def find_item(item_id: int) -> Optional[str]: means the function can return a string or None if the item is not found.

Are there any tools to check type hints in my code?

Yes! You can use tools like mypy to check for type hint correctness in your Python code. It helps catch type errors before runtime.