perf: use struct{} for done channel in timer instead of bool

timer.go

@@ -25,7 +25,7 @@ type timer struct{
 	fun *rt.Closure
 	th *timerHandler
 	ticker *time.Ticker
-	channel chan bool
+	channel chan struct{}
 }
 
 func (t *timer) start() error {
@@ -65,7 +65,7 @@ func (t *timer) stop() error {
 		return errors.New("timer not running")
 	}
 
-	t.channel <- true
+	t.channel <- struct{}{}
 	t.running = false
 	t.th.running--
 	

timerhandler.go

@@ -34,7 +34,7 @@ func (th *timerHandler) create(typ timerType, dur time.Duration, fun *rt.Closure
 		typ: typ,
 		fun: fun,
 		dur: dur,
-		channel: make(chan bool, 1),
+		channel: make(chan struct{}, 1),
 		th: th,
 		id: th.latestID,
 	}