[papaver]

can't say i'm a fan of the decorator to implement functional concepts. jut feels dirty. type hints in python are just as meh. feels like it's not taking advantage of pythons duck typing.

a version of try and either, with a decent do notation taking advantage of for comprehension... https://github.com/papaver/pyfnz

[ca_parody]

I think if that some of these concepts should just be included with the 3.9 Annotated Type

    Annotated[IO[str], unpure]

in 3.9 and above if the authors want to commit to type hints being core to this. I agree that the decorators feel a little wrong