ing</span></code></div></div><div class="odoc-spec"><div class="spec value anchored" id="val-fold_left"><a href="#val-fold_left" class="anchor"></a><code><span><span class="keyword">val</span> fold_left : <span><span class="label">f</span>:<span>(<span><span class="type-var">'acc</span> <span class="arrow">&#45;&gt;</span></span> <span>char <span class="arrow">&#45;&gt;</span></span> <span class="type-var">'acc</span>)</span> <span class="arrow">&#45;&gt;</span></span> <span><span class="label">init</span>: