 In</h4>
        <a href="../../protocol/CollectionType/"><code>CollectionType</code></a>,    <a href="../../protocol/SequenceType/"><code>SequenceType</code></a>    
</div></div>
</div>
<div class="declaration inherited" id="func-popfirst">
<a class="toggle-link" data-toggle="collapse" href="#comment-func-popfirst">mutating func popFirst()</a>
        
<div class="comment collapse" id="comment-func-popfirst"><div class="p">
    <p>If <code>!self.isEmpty</code>, remove the first element and return it, other