Usefulness of the "not in" operator

[Chris Angelico]

On Sun, Oct 9, 2011 at 1:40 AM, candide <candide at free.invalid> wrote:
> A notin operator or isnot operator would be less confusing (at least in my
> case ;) ).
>

Let's replace both of them.

in --> foo extant bar
not in --> foo extinct bar

That would solve the problem, wouldn't it?

*ducking for cover*

ChrisA