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crates/exex/exex/src/manager.rs

@@ -172,12 +172,19 @@ impl ExExNotificationsSubscriber {
 
     /// Subscribe to notifications with the given head. Notifications will be sent starting from the
     /// head, not inclusive.
+    ///
+    /// When the return value is dropped, the subscription is cancelled.
     pub fn subscribe_with_head(&mut self, head: ExExHead) -> &mut ExExNotifications {
         self.state_tx.send(ExExNotificationsState::Active(Some(head))).unwrap();
         &mut self.notifications
     }
 
     /// Subscribe to notifications.
+    ///
+    /// When the return value is dropped, the subscription is cancelled.
+    /// It means that you will miss some of the notifications that could have arrived while the
+    /// subscription is inactive. To prevent this, you can use [`Self::subscribe_with_head`] to
+    /// explictly pass the head where you stopped and continue from there.
     pub fn subscribe(&mut self) -> &mut ExExNotifications {
         self.state_tx.send(ExExNotificationsState::Active(None)).unwrap();
         &mut self.notifications