 class="callable inherited">
          <span class="name"><a href="dart-async/Stream/contains.html">contains</a></span><span class="signature">(<wbr><span class="parameter" id="contains-param-needle"><span class="type-annotation"><a href="dart-core/Object-class.html">Object</a></span> <span class="parameter-name">needle</span></span>)
            <span class="returntype parameter">&#8594; <a href="dart-async/Future-class.html">Future</a><span class="signature">&lt;<wbr><span class="type-parameter"><a href="