title: Dart/WebStorm "Cancel instances of dart.async.StreamSubscription"
body: <p>I am using WenStorm 2018.2.5 (registered), with the Dart plugin.</p>
  
  <p>While editing a simple code, the editor shows me a message:</p>
  
  <blockquote>
    <p>Cancel instances of dart.async.StreamSubscription</p>
  </blockquote>
  
  <p><a href="https://i.stack.imgur.com/8YZNj.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/8YZNj.png" alt="enter image description here"></a></p>
  
  <p>I don't understand what this message means. I don't see what's wrong with the code. And, if I run the code inspection, the result is : "<code>No suspicious code found</code>".</p>
  
  <p>Any idea ?</p>
  
  <p>Note :</p>
  
  <pre><code>const int eventsCount = 5;
  const int waitBetweenTwoEvents = 1;
  
  typedef Streamer = Stream&lt;int&gt; Function();
  
  ...
  
  Streamer streamCreator = () async* {
    for(int i=0; i&lt;eventsCount; i++) {
      yield i;
      sleep(Duration(seconds: waitBetweenTwoEvents));
    }
  };
  </code></pre>