e></div><div class="spec-doc"><p>Same as <a href="#val-fold_joined"><code>fold_joined</code></a>, but wraps each line of stdin in <code>Ok</code> and lines of stderr in <code>Error</code> so they can be distinguished. This function uses asynchronous I/O internally, so the optional <code>sleep</code> parameter is provided as a means to pause briefly if output is expected to be slow to avoid pegging the CPU with a loop that does nothing.</p></div></div><div class="odoc-spec"><div class="spec value anchored" i