   
    </section>
    <section class="desc markdown">
      <p>Returns a future that handles the <a href="dart-async/StreamSubscription/onDone.html">onDone</a> and <a href="dart-async/StreamSubscription/onError.html">onError</a> callbacks.</p>
<p>This method <em>overwrites</em> the existing <a href="dart-async/StreamSubscription/onDone.html">onDone</a> and <a href="dart-async/StreamSubscription/onError.html">onError</a> callbacks
with new ones that complete the returned future.</p>
<p>In case of an error t