Baptiste Carvello wrote:
y = config["handler"]["parameters"]["y"] with KeyError as None
I love the look of this! While it doesn't address everything that PEP505 does, that's IMO a good thing, because - as other people mentioned already - None does too many things already. On another note, the whole discussion reminds me of wg21.link/p0798, which is about adding something quite similar to C++ (was accepted into C++23), and contains a decent overview of how other languages solve the same thing. Even though the approach there is probably not applicable (as all python types are implicitly `Optional` in the sense of "can be None", i.e. that API would have to be added all the way down to `object`), it's still ironic that C++'s `and_then` looks more pythonic than what's proposed here.