rustprint2.rs

  #[derive(Debug)]
  struct Color {
    red: u8,
    green: u8,
    blue: u8,
  }
  impl fmt::Display for Color {
    // `f` is a buffer, this method must write the formatted string into it
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
      write!(f, "RGB ({0}, {1}, {2}) 0X{0:02.X}{1:02.X}{2:02.X}",
         self.red, self.green, self.blue)
    }
  }