d(<wbr>_:)</a>
     <span class="required">Required</span>    
<div class="comment collapse" id="comment-func-extend_"><div class="p">
    <p>Append the elements of <code>newElements</code> to <code>self</code>.</p>

<p>Complexity: O(<em>length of result</em>) </p>

<p>A possible implementation:</p>

<pre><code class="language-swift">reserveCapacity(count(self) + underestimateCount(newElements))
for x in newElements {
  self.append(x)
}</code></pre>

    <h4>Declaration</h4>    
    <code class="language-sw