docs: add comment

1 files changed, 1 insertions, 0 deletions

diff --git a/main.go b/main.go
index 96853d8..c2f007f 100644
--- a/main.go
+++ b/main.go
@@ -8,6 +8,7 @@ import (
 	"time"
 )
 
+// A silly Ball type based on the original ping-pong example.
 type Ball struct{ hits int }
 
 func main() {