2 files changed, 12 insertions, 6 deletions
diff --git a/futures/src/subscription.rs b/futures/src/subscription.rs
index 0085886d..0479c63c 100644
--- a/futures/src/subscription.rs
+++ b/futures/src/subscription.rs
@@ -183,11 +183,7 @@ where
 
         let mapper = self.mapper;
 
-        Box::pin(
-            self.recipe
-                .stream(input)
-                .map(move |element| mapper(element)),
-        )
+        Box::pin(self.recipe.stream(input).map(mapper))
     }
 }
 
diff --git a/futures/src/subscription/tracker.rs b/futures/src/subscription/tracker.rs
index 2cf98284..9fe110b0 100644
--- a/futures/src/subscription/tracker.rs
+++ b/futures/src/subscription/tracker.rs
@@ -127,7 +127,7 @@ where
             futures.push(Box::pin(future));
         }
 
-        self.subscriptions.retain(|id, _| alive.contains(&id));
+        self.subscriptions.retain(|id, _| alive.contains(id));
 
         futures
     }
@@ -156,3 +156,13 @@ where
             });
     }
 }
+
+impl<Hasher, Event> Default for Tracker<Hasher, Event>
+where
+    Hasher: std::hash::Hasher + Default,
+    Event: 'static + Send + Clone,
+{
+    fn default() -> Self {
+        Self::new()
+    }
+}