ction/DoubleLinkedQueue-class.html">this</a>. <a href="dart-collection/DoubleLinkedQueue/length.html">[...]</a>
          <div class="features">read-only</div>
</dd>
        <dt id="single" class="property">
          <span class="name"><a href="dart-collection/DoubleLinkedQueue/single.html">single</a></span>
          <span class="signature">&#8594; E</span>
        </dt>
        <dd>
          Checks that this iterable has only one element, and returns that element. <a href="dart-collection/DoubleLinkedQu