diff --git a/vlib/sync/once.v b/vlib/sync/once.v
index 9dff78ffc4..9afa8e2e2d 100644
--- a/vlib/sync/once.v
+++ b/vlib/sync/once.v
@@ -41,6 +41,7 @@ fn (mut o Once) do_slow(f fn ()) {
 //        o.add(5)
 // })
 // ```
+//
 // ... you can use:
 // ```v
 //    once.do_with_param(fn (mut o One) {