What are the differences between type hints and type annotations?

What are the differences between type hints and type annotations?

Type hints and type annotations are often used interchangeably, but they have subtle differences. Type hints are a broader concept that refers to any indication of the type of a variable, while type annotations specifically refer to the syntax used in Python to declare the type of a variable or function parameter.

Can you give me an example of each?

Sure! A type hint could be a comment indicating the expected type, like # type: int. A type annotation would be something like def add(a: int, b: int) -> int: where the types are explicitly declared in the function signature.

Are type annotations mandatory in Python?

No, type annotations are not mandatory in Python. They are optional and primarily used for type checking and improving code readability.

How do type hints improve code quality?

Type hints help catch errors early by allowing static type checkers to analyze the code. They also enhance documentation and make it easier for developers to understand the expected types.