more idiomatic with closure

src/main.rs

@@ -35,13 +35,10 @@ impl <T> List<T> {
     }
 
     pub fn pop(&mut self) -> Option<T> {
-        match self.head.take() {
-            None => None,
-            Some(node) => {
+        self.head.take().map(|node| {
             self.head = node.next;
-                Some(node.elem)
-            }
-        }
+            node.elem
+        })
     }
 }
 
@@ -54,6 +51,6 @@ mod tests {
     fn test() {
         let mut list = List::new();
         list.push(42);
-        println!("{:?}", list);
+        assert_eq!(Some(42), list.pop());
     }
 }