updated comments of throttler

pkg/support/throttling/throttler.go

@@ -6,6 +6,10 @@ import (
 
 // Throttling notifications to prometheus and web clients
 // TO be used in a single-threaded manner.
+//
+// NOTE: the null value of type T is considered as a not-set value.
+//
+//	The best usage of Throttler is with a pointer type.
 type Throttler[T comparable] struct {
 	minDelay time.Duration
 	// ucntion to call to implement the notification.
@@ -49,7 +53,6 @@ func (throttler *Throttler[T]) Notify(value T) {
 // notification was sent is long enough ago.
 func (throttler *Throttler[T]) Ping() {
 	if throttler.pendingValue != *new(T) {
-		// TODO improve: use a better way to recognize that there is a pending value.
 		throttler.Notify(throttler.pendingValue)
 	}
 }