ops_shl_vec.rs

use std::ops::Shl;

#[derive(Debug)]
struct V<T>(Vec<T>);

impl<T> Shl<usize> for V<T> {
    type Output = Self;
    fn shl(mut self, rhs: usize) -> V<T> {
        let l = self.0.len();
        rotate_by(&mut self.0, 0, rhs-1);
        rotate_by(&mut self.0, rhs, l-1);
        rotate_by(&mut self.0, 0, l-1);

        fn rotate_by<T>(arr: &mut [T], mut left: usize, mut right: usize) {
            while left < right {
                arr.swap(left, right);
                left += 1;
                right -= 1;
            }
        }
        self
    }
}

fn main() {
    let v_ = vec![1,2,3,4,5];
    let v = V(v_);
    println!("{:?}", (v << 2));
}