struct Wrapper<T> { value: T, } impl<T> Wrapper<T> { fn new(value: T) -> Self { Wrapper { value } } } fn main() { // You can optionally experiment here. } #[cfg(test)] mod tests { use super::*; #[test] fn store_u32_in_wrapper() { assert_eq!(Wrapper::new(42).value, 42); } #[test] fn store_str_in_wrapper() { assert_eq!(Wrapper::new("Foo").value, "Foo"); } }