if_the_priority_queue_is_empty.">Check if the priority queue is empty.</a></h4>
  O(1)</p>

<h3 class="function"><a name="is_queue-1">is_queue/1</a></h3>
<div class="spec">
<p><tt>is_queue(X1::<a href="#type-pqueue">pqueue()</a>) -&gt; true | false</tt><br></p>
</div><p>
  <h4><a name="Check_if_the_priority_queue_type_is_as_expected.">Check if the priority queue type is as expected.</a></h4>
  O(1)</p>

<h3 class="function"><a name="join-2">join/2</a></h3>
<div class="spec">
<p><tt>join(X1::<a href="#type-p