Function treeid::bitter::rotate_add

pub fn rotate_add(x: u8, y: u8) -> u8

Adds y to x, rotating back to 0 if the result exceeds 8.

No distinction is made in the number of rotations.

use treeid::bitter::*;
assert_eq!(1, rotate_add(0, 1));
assert_eq!(7, rotate_add(0, 7));
assert_eq!(0, rotate_add(0, 8));
assert_eq!(1, rotate_add(0, 9));
assert_eq!(7, rotate_add(0, 15));
assert_eq!(0, rotate_add(0, 16));