Usefulness of the "not in" operator

[Chris Angelico]

On Sun, Oct 9, 2011 at 3:31 AM, rusi <rustompmody at gmail.com> wrote:
>> If you want to take it one step further, all the boolean operators can
>> be derived from nand (the dualists would insist on using nor).
>                        ^^^^^^^^^^^^
> ????
>

I'm not sure what you're questioning, but it's possible to derive all
boolean operators from either nand or nor. Most hardware these days is
built out of silicon NAND gates, but there's no reason not to do it as
NOR gates.

ChrisA