Spent basically the entire day (except for the mandatory walk) fighting with Python’s type hints. But, the result is that my widget toolkit now passes mypy --strict.

I really, really don’t want to write larger pieces of software without static typing anymore. With dynamic typing, you must test every code path in your program to catch even the most basic errors. pylint helps a bit (doesn’t need type hints), but that’s really not enough.

Also, somewhere along the way, I picked up a very bad (Python) programming style. (Actually, I know exactly where I picked that up, but I don’t want to point the finger now.) This style makes heavy use of dicts and tuples instead of proper classes. That works for small scripts, but it very quickly turns into an absolute mess once the program grows. Prime example: jenny. 😩

I have a love-hate relationship with Python’s type hints, because they are meaningless at runtime, so they can be utterly misleading. I’m beginning to like them as an additional safety-net, though.

(But really, if correctness is the goal, you either need to invest a ton of time to get 100% test coverage – or don’t use Python.)