struct Wrapper<T> {
    value: T,
impl<T> Wrapper<T> {
    pub fn new(value: T) -> Self {
        Wrapper { value }

By declaring T as a generic type after impl, Rust can identify that the type in the angle brackets in Point is a generic type rather than a concrete type.


// Define a function `printer` that takes a generic type `T` which
// must implement trait `Display`.
fn printer<T: Display>(t: T) {
    println!("{}", t);