Hi all,

I've only here found out that there is a discussion going on about those
none-aware operators and my first thought was "great, finally!". FWIW,
I'd be happy with the syntax suggestion in the PEP, since '?' looks
rather intuitive to me to mean something like "maybe".

However, I then read the mentioned post of Steve Dower, with the final
summary:

 > So to summarise my core concern - allowing an API designer to "just
use None" is a cop out, and it lets people write lazy/bad APIs rather
than coming up with good ones.

This is a very good point. In fact, I've never really thought about it
that way and of course he's totally right that "SomeType | None" (or
Optional[SomeType], which also somehow made me feel that this usage is
fairly intended) is not optimal, at least for user defined
types/classes. The problem is, that I never actually thought about his
suggested way. And I wouldn't be surprised if this holds for many other
people as well.

Maybe it would be great to boldly mention these thoughts in the
documentation at an appropriate place. In my opinion, there are at least
the following good places where this would fit nicely:

- The documentation of the dataclasses
(https://docs.python.org/3/library/dataclasses.html), since this is
probably the most common use case for the "| None" pattern. Going
further, the dataclasses functionality might even be extended to make it
simpler to generate such null-types (or however they are called), so
that it is no longer "a tonne more work".

- Linters like pylint could emit a note when seeing the "| None"
pattern, linking to the explanation about why it is possibly not the
best way to do it.

- The documentation of the discussed None-aware operators. Since these
new operators are closely coupled to the arguably suboptimal "| None"
pattern, it is probably good to tell folks right there why they should
consider better alternatives.

As mentioned, I absolutely see Steve's point. However, there are many
Python scripts/programs working without a complex API, where this "|
None" pattern may still have its legitimate uses and the none-aware
operators can make code easier to read (and write).

Best regards,
Philipp
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