proc" class="anchor"></a><code><span><span class="keyword">val</span> fold_both_proc : 
  <span><span class="optlabel">?sleep</span>:float <span class="arrow">&#45;&gt;</span></span>
  <span><span><span>(<span class="type-var">'stdin</span>, <a href="#type-pipe">pipe</a>, <a href="#type-pipe">pipe</a>)</span> <a href="#type-t">t</a></span> <span class="arrow">&#45;&gt;</span></span>
  <span><span class="label">f</span>:<span>(<span><span class="type-var">'acc</span> <span class="arrow">&#45;&gt;</span></spa