#![feature(core_intrinsics)]
fn print_type_of<T>(_: &T) {
    println!("{}", unsafe { std::intrinsics::type_name::<T>() });
}

struct Wrapper(i32);

fn main() {
    let v: Vec<_> = vec![Wrapper(1)];
    for item in v.iter()
    {
        print_type_of(&item);   //the type of item is &Wrapper
    }
    for &Wrapper(item) in v.iter()
    {
        print_type_of(&item);   //the type of item is i32
    }

}