1 files changed, 14 insertions, 0 deletions
diff --git a/src/doc/book/listings/ch19-advanced-features/listing-19-23/src/main.rs b/src/doc/book/listings/ch19-advanced-features/listing-19-23/src/main.rs
new file mode 100644
index 000000000..eae46c92f
--- /dev/null
+++ b/src/doc/book/listings/ch19-advanced-features/listing-19-23/src/main.rs
@@ -0,0 +1,14 @@
+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);
+}