use std::fmt::{self, Display, Formatter}; struct City { name: &'static str, lat: f32, lon: f32, } impl Display for City { fn fmt(&self, f: &mut Formatter) -> fmt::Result { let lat_c = if self.lat >= 0.0 { 'N' } else { 'S' }; let lon_c = if self.lon >= 0.0 { 'E' } else { 'W' }; write!( f, "{}: {:.3}°{} {:.3}°{}", self.name, self.lat.abs(), lat_c, self.lon.abs(), lon_c ) } } #[derive(Debug)] struct Color { red: u8, green: u8, blue: u8, } impl Display for Color { fn fmt(&self, f: &mut Formatter) -> fmt::Result { write!( f, "RGB ({}, {}, {}) 0x{:02X}{:02X}{:02X}", self.red, self.green, self.blue, self.red, self.green, self.blue ) } } fn main() { for city in [ City { name: "Dublin", lat: 53.347778, lon: -6.259722, }, City { name: "Oslo", lat: 59.95, lon: 10.75, }, City { name: "Vancouver", lat: 49.25, lon: -123.1, }, ] .iter() { println!("{}", *city); } for color in [ Color { red: 128, green: 255, blue: 90, }, Color { red: 0, green: 3, blue: 254, }, Color { red: 0, green: 0, blue: 0, }, ] .iter() { println!("{}", *color); } }