old"><a href="#val-fold" class="anchor"></a><code><span class="keyword">val</span> fold : <span><span class="type-var">'a</span> <a href="index.html#type-t">t</a></span> <span>&#45;&gt;</span> <span>init:<span class="type-var">'accum</span></span> <span>&#45;&gt;</span> <span>f:<span>(<span class="type-var">'accum</span> <span>&#45;&gt;</span> <span class="type-var">'a</span> <span>&#45;&gt;</span> <span class="type-var">'accum</span>)</span></span> <span>&#45;&gt;</span> <span class="type-var">'accum</span