not operator operator..

[Wang Zhen]

S. Chancellor wrote:
> I really really hate the !in, !is syntax.   I think a lot of other 
> people do too. I propose that the word not, become an operator on 
> operators.  For example:
> 
> Foo not is null
> Foo not in Bar
> 
> This not keyword will only function when it is part of these expressions:
> 
> EqualExpression
> RelExpression
> InExpression
> 
> As a consequence the following would be valid:
> 
> Foo not == Bar
> Foo not <= Bar
> 
> -S.
> 

I don't hate !is and !in, but if they were to change, I would suggest a 
more succinct syntax:

!is => not
!in => out