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src/context/list.rs

@@ -50,7 +50,7 @@ impl<'a, T> Iterator for Iter<'a, T> {
 
     fn next(&mut self) -> Option<Self::Item> {
         let ret = self.next.map(|link| link.get_data());
-        self.next = self.next.map(|link| link.get_parent()).flatten();
+        self.next = self.next.and_then(|link| link.get_parent());
         ret
     }
 }