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use std::fmt::Display;
struct Pair<T> {
x: T,
y: T,
}
impl<T> Pair<T> {
fn new(x: T, y: T) -> Self {
Self {
x,
y,
}
}
}
impl<T: Display + PartialOrd> Pair<T> {
fn cmp_display(&self) {
if self.x >= self.y {
println!("{}", self.x);
}
else {
println!("{}", self.y);
}
}
}
pub trait Summary {
fn summarize(&self) -> String {
format!("(read more from {}...)", self.summarize_author())
}
fn summarize_author(&self) -> String;
}
pub struct NewsArticle {
pub headline: String,
pub location: String,
pub author: String,
pub content: String,
}
impl Summary for NewsArticle {
// fn summarize(&self) -> String {
// format!("{}, by {} ({})", self.headline, self.author, self.location)
// }
fn summarize_author(&self) -> String {
format!("{}", self.author)
}
}
pub struct Tweet {
pub username: String,
pub content: String,
pub reply: bool,
pub retweet: bool,
}
impl Summary for Tweet {
// fn summarize(&self) -> String {
// format!("{}: {}", self.username, self.content)
// }
fn summarize_author(&self) -> String {
format!("@{}", self.username)
}
}
pub fn notify(item: impl Summary) {
println!("breaking news: {}", item.summarize());
}
fn returns_summarizable() -> impl Summary {
NewsArticle {
headline: String::from("Penguins win the stanley cup championship!"),
location: String::from("Pittsburgh, PA, USA"),
author: String::from("Iceburgh"),
content: String::from("The pittsburgh penguins are winners I guess."),
}
// Tweet {
// username: String::from("horse_ebooks"),
// content: String::from("of course blargh"),
// reply: false,
// retweet: false,
// }
}
fn main() {
let tweet = Tweet {
username: String::from("horse_ebooks"),
content: String::from("of course, as you probably already know, people"),
reply: false,
retweet: false,
};
//dbg!(tweet.summarize());
let article = NewsArticle {
headline: String::from("Penguins win the stanley cup championship!"),
location: String::from("Pittsburgh, PA, USA"),
author: String::from("Iceburgh"),
content: String::from("The pittsburgh penguins are winners I guess."),
};
//dbg!(article.summarize());
//notify(tweet);
returns_summarizable();
}
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