traits1 solution

exercises/15_traits/traits1.rs

@@ -1,19 +1,17 @@
-// Time to implement some traits! Your task is to implement the trait
-// `AppendBar` for the type `String`. The trait AppendBar has only one function,
-// which appends "Bar" to any object implementing this trait.
-
+// The trait `AppendBar` has only one function which appends "Bar" to any object
+// implementing this trait.
 trait AppendBar {
     fn append_bar(self) -> Self;
 }
 
 impl AppendBar for String {
-    // TODO: Implement `AppendBar` for type `String`.
+    // TODO: Implement `AppendBar` for the type `String`.
 }
 
 fn main() {
     let s = String::from("Foo");
     let s = s.append_bar();
-    println!("s: {}", s);
+    println!("s: {s}");
 }
 
 #[cfg(test)]
@@ -22,14 +20,11 @@ mod tests {
 
     #[test]
     fn is_foo_bar() {
-        assert_eq!(String::from("Foo").append_bar(), String::from("FooBar"));
+        assert_eq!(String::from("Foo").append_bar(), "FooBar");
     }
 
     #[test]
     fn is_bar_bar() {
-        assert_eq!(
-            String::from("").append_bar().append_bar(),
-            String::from("BarBar")
-        );
+        assert_eq!(String::from("").append_bar().append_bar(), "BarBar");
     }
 }

solutions/15_traits/traits1.rs

@@ -1 +1,32 @@
-// Solutions will be available before the stable release. Thank you for testing the beta version 🥰
+// The trait `AppendBar` has only one function which appends "Bar" to any object
+// implementing this trait.
+trait AppendBar {
+    fn append_bar(self) -> Self;
+}
+
+impl AppendBar for String {
+    fn append_bar(self) -> Self {
+        self + "Bar"
+    }
+}
+
+fn main() {
+    let s = String::from("Foo");
+    let s = s.append_bar();
+    println!("s: {s}");
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn is_foo_bar() {
+        assert_eq!(String::from("Foo").append_bar(), "FooBar");
+    }
+
+    #[test]
+    fn is_bar_bar() {
+        assert_eq!(String::from("").append_bar().append_bar(), "BarBar");
+    }
+}