countUntil with negated pre-defined predicate?

[Harry Gillanders]

On Saturday, 2 May 2020 at 18:23:30 UTC, Robert M. Münch wrote:
> This works:
>
> 	countUntil!(std.uni.isWhite)("hello world"))
>
> How can I switch this to (not working);
>
> 	countUntil!(!std.uni.isWhite)("hello world"))
>
> without having to write my own predicate?
>
> Or is there an even better way to search for all "drawable 
> unicode characters"?

std.functional.not can do this: 
https://dlang.org/phobos/std_functional.html#not