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|
//fn main() {
// println!("Hello, world!");
//}
//
//pub trait Iterator {
// type Item;
//
// fn next(&mut self) -> Option<Self::Item>;
//}
//
//
//#[derive(Debug, PartialEq)]
//struct Point {
// x: i32,
// y: i32,
//}
//
//impl Add for Point {
// type Output = Point;
//
// fn add(self, other: Point) -> Point {
// Point {
// x: self.x + other.x,
// y: self.y + other.y,
// }
// }
//}
//fn main() {
// assert_eq!(Point { x: 1, y: 0 } + Point { x: 2, y: 3 },
// Point { x: 3, y: 3 });
// println!("Done.");
//}
//trait Add<RHS=Self> {
// type Output;
//
// fn add(self, rhs: RHS) -> Self::Output;
//}
//use std::ops::Add;
//
//struct Millimeters(u32);
//struct Meters(u32);
//
//impl Add<Meters> for Millimeters {
// type Output = Millimeters;
//
// fn add(self, other: Meters) -> Millimeters {
// Millimeters(self.0 + (other.0 * 1000))
// }
//}
//trait Pilot {
// fn fly(&self);
//}
//
//trait Wizard {
// fn fly(&self);
//}
//
//struct Human;
//
//impl Pilot for Human {
// fn fly(&self) {
// println!("Because I was inverted.");
// }
//}
//
//impl Wizard for Human {
// fn fly(&self) {
// println!("Fly, you fools.");
// }
//}
//
//impl Human {
// fn fly(&self) {
// println!("*feels real loose like a long-neck goose*");
// }
//}
//
//
//trait Animal {
// fn baby_name() -> String;
//}
//
//struct Dog;
//
//impl Dog {
// fn baby_name() -> String {
// String::from("Spot")
// }
//}
//
//impl Animal for Dog {
// fn baby_name() -> String {
// String::from("puppy")
// }
//}
//fn main() {
// let person = Human;
// person.fly();
// Pilot::fly(&person);
// Wizard::fly(&person);
//
//
// println!("A baby dog is called a {}", <Dog as Animal>::baby_name());
//
//
// println!("Done.");
//}
//
//use std::fmt;
//
//trait OutlinePrint: fmt::Display {
// fn outline_print(&self) {
// let output = self.to_string();
// let len = output.len();
// println!("{}", "*".repeat(len + 4));
// println!("*{}*", " ".repeat(len + 2));
// println!("* {} *", output);
// println!("*{}*", " ".repeat(len + 2));
// println!("{}", "*".repeat(len + 4));
// }
//}
//
//struct Point {
// x: i32,
// y: i32,
//}
//
//impl OutlinePrint for Point {}
//
//impl fmt::Display for Point {
// fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
// write!(f, "({}, {})", self.x, self.y)
// }
//}
//
//fn main() {
// let point = Point { x: 5, y: 6 };
// point.outline_print();
//}
use std::fmt;
struct Wrapper(Vec<String>);
impl fmt::Display for Wrapper {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "[{}]", self.0.join(", "))
}
}
fn main() {
let w = Wrapper(vec![String::from("hello"), String::from("world")]);
println!("w = {}", w);
}
|
