#[derive(Debug)]
pub struct Test<T> where T: AsRef<[u8]> {
    thing: T,
}

fn main() {
    let x: Test<String> = make("cats".to_owned());
    dbg!(x);
}

fn make<T: AsRef<[u8]>>(i: T) -> Test<T> {
    Test{
        thing: i,
    }
}