Austin Z. Henley Associate Teaching Professor
Carnegie Mellon University [email protected]
@austinzhenley
github/AZHenley
Baby's first type checker
8/31/2025
Have you ever wondered how type checking works? Me too—let's make one!
Python allows optional type annotations like this:
def foobar(name: str | None) -> str: return "Fizz!" buzz: int = 42
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