are computed from events of the
provided <code>stream</code>.</p>
<p>The <a href="dart-async/StreamTransformer-class.html">StreamTransformer</a> interface is completely generic,
so it cannot say what subclasses do.
Each <a href="dart-async/StreamTransformer-class.html">StreamTransformer</a> should document clearly how it transforms the
stream (on the class or variable used to access the transformer),
as well as any differences from the following typical behavior:</p>
<ul>
<li>When the returned stream is lis