[question] Is there a preferred way to encode the "unit" type? about koda

[keithasaurus]

For the empty tuple interpretation, pep 484 says you can do x: tuple[()] = (). And this does type-check in mypy. For the result example, I'd probably use Result[None, str], but more likely I'd just do Maybe[str]:

def example(...) -> Maybe[str]:
  if ...:
      return nothing
  else:
      return Just("something went wrong")

Depends on what you want to do.

For more general validation, there is a companion library to koda called 9koda-validate](https://github.com/keithasaurus/koda-validate).