</span> <span class="n">f</span><span class="p">(</span><span class="n">reverse_fold</span><span class="p">(</span><span class="n">f</span><span class="p">)(</span><span class="n">xs</span><span class="p">...),</span> <span class="n">x</span><span class="p">));</span>
</pre></div>
</div>
</div>
<div class="section" id="requirements">
<h2>Requirements<a class="headerlink" href="#requirements" title="Permalink to this headline">¶</a></h2>
<p>State must be:</p>
<ul class="simple">
<li>CopyConstructible</li>
<