diff --git a/src/robot.rs b/src/robot.rs
index b40ec1e..bedefa3 100644
--- a/src/robot.rs
+++ b/src/robot.rs
@@ -34,7 +34,7 @@ impl Robot {
                     Orientation::S => self.p.y -= 1,
                     Orientation::W => self.p.x -= 1,
                 },
-                _ => (),
+                _ => (), // never happens 😉
             },
             None => (),
         }