Started Rust in Action MEAP.

1 files changed, 114 insertions, 0 deletions

diff --git a/rust-book/traits/src/main.rs b/rust-book/traits/src/main.rs
new file mode 100755
index 0000000..770caa9
--- /dev/null
+++ b/rust-book/traits/src/main.rs
@@ -0,0 +1,114 @@
+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();
+}