1 files changed, 22 insertions, 0 deletions
diff --git a/src/doc/book/listings/ch13-functional-features/listing-13-08/src/main.rs b/src/doc/book/listings/ch13-functional-features/listing-13-08/src/main.rs
new file mode 100644
index 000000000..3b9c9cbdf
--- /dev/null
+++ b/src/doc/book/listings/ch13-functional-features/listing-13-08/src/main.rs
@@ -0,0 +1,22 @@
+#[derive(Debug)]
+struct Rectangle {
+    width: u32,
+    height: u32,
+}
+
+fn main() {
+    let mut list = [
+        Rectangle { width: 10, height: 1 },
+        Rectangle { width: 3, height: 5 },
+        Rectangle { width: 7, height: 12 },
+    ];
+
+    let mut sort_operations = vec![];
+    let value = String::from("by key called");
+
+    list.sort_by_key(|r| {
+        sort_operations.push(value);
+        r.width
+    });
+    println!("{:#?}", list);
+}