1pub trait Summary {
2 fn summarize(&self) -> String {
3 String::from("Loading...")
4 }
5}
6
7pub struct NewsArticle {
8 pub headline: String,
9 pub location: String,
10 pub author: String,
11 pub content: String,
12}
13
14impl Summary for NewsArticle {
15 }
19
20pub struct Tweet {
21 pub username: String,
22 pub content: String,
23 pub reply: bool,
24 pub retweet: bool,
25}
26
27impl Summary for Tweet {
28 fn summarize(&self) -> String {
29 format!("我是Tweet的summarize: {}", self.username)
30 }
31}