16.3 Generic enum

In the following example we use a parametric type T to define a generic enum type to represent colors. The possible levels of grey or each color component (i.e.: red, green, blue) is stored as a value of the specified type:

:clear

#[derive(Debug)]
enum Color<T> {
  Grey(T),
  Rgb(T, T, T),
}

To use the Color<T> enum type, we must specify what is T:

let c1 = Color::<u8>::Grey(0xa0);
let c2 = Color::<u16>::Grey(0xff00);
let c3 = Color::<u8>::Rgb(0x00, 0xa0, 0x57);
(c1, c2, c3)

see solution