On Jan 16, 2015, at 13:47, Guido van Rossum <guido@python.org> wrote:

On Fri, Jan 16, 2015 at 1:08 PM, Petr Viktorin <encukou@gmail.com> wrote:

"On Fri, Jan 16, 2015 at 6:17 PM, Guido van Rossum <guido@python.org> wrote:

[...]
> * WINDOWS
>
> * UNIXOID, equivalent to ``not WINDOWS``

I wonder what the use cases are here. Is this useful, as a dichotomy,
outside of asyncio (or other low-level stdlib code)?

The stdlib is full of things that work differently on Windows.

The stdlib is also full of things that work one way on Windows, another way on Unix, and another way (or, often, not at all) on (all, or specific) other platforms,

I realize nobody is building Python 3.5 for classic Mac or Symbian S60 or MicroVMS, but do we need to bake in as a permanent assumption that Python will never again run on a non-Windows non-POSIX-ish system?

You already have both WINDOWS and UNIXOID; why not just remove the statement that one is the negation of the other?