!in operator?

[bearophile]

Jason House:
> Method 1 essentially calls in twice while method 2 calls in once.

Sometimes I just want to know if something isn't present.
Having !in doesn't prevent me from writing and using x = y in aa; when I want it.


> PS: Please don't assume that I'm advocating not having a !in operator. I'm just pointing out possible reasons it may have been avoided.<

I think that's not a possible reason :-)

Bye,
bearophile