trait Lazy<T> {
    fn force(self) -> T;
}

struct LazyVal<T>(pub T);
fn lazy<T>(val: T) -> LazyVal<T> {
    LazyVal(val)
}

impl<T, S: FnOnce() -> T> Lazy<T> for S {
  fn force(self) -> T {
      self()
  }
}

impl<T> Lazy<T> for LazyVal<T> {
    fn force(self) -> T {
        self.0
    }
}

fn get<T, V: Lazy<T>>(val: V) -> T {
  val.force()
}

fn main() {
    let val = || 5;
    let forced = get(val);
    let reforced = get(lazy(forced));
    println!("Hello {}, {}", forced, reforced);
}