s -&gt; Int?</code>
    
        <h4>Declared In</h4>
        <a href="../../protocol/CollectionType/"><code>CollectionType</code></a>    
</div></div>
</div>
<div class="declaration" id="func-insert_atindex_">
<a class="toggle-link" data-toggle="collapse" href="#comment-func-insert_atindex_">mutating func insert(<wbr>_:<wbr>atIndex:)</a>
        
<div class="comment collapse" id="comment-func-insert_atindex_"><div class="p">
    <p>Insert <code>newElement</code> at index <code>i</code>.</p>

<p><strong>Req