use std::fmt::{self,Display,Formatter};
use std::string::ToString;

struct Foo<T>(T);

impl<T: Display> Display for Foo<T> {
    fn fmt(&self, _f: &mut Formatter) -> fmt::Result {
        Ok(())
    }
}

fn main() {
    let to_string = ToString::to_string;
    let i = 1;
    let b = &i;
    assert_eq!("bar", to_string(&b));
}