iv class="info-desc">
<p><code class="code">rev_map2&nbsp;f&nbsp;l1&nbsp;l2</code> gives the same result as
   <a href="List.html#VALrev"><code class="code">List.rev</code></a><code class="code">&nbsp;(</code><a href="List.html#VALmap2"><code class="code">List.map2</code></a><code class="code">&nbsp;f&nbsp;l1&nbsp;l2)</code>, but is tail-recursive and
   more efficient.</p>
</div>
</div>

<pre id="VALfold_left2">val fold_left2 : ('a -&gt; 'b -&gt; 'c -&gt; 'a) -&gt; 'a -&gt; 'b list -&gt; 'c list -&gt; 'a</