onstructor">Node</span> <span class="keyword">of</span> <a href="#type-node">node</a> * <span><span>(<a href="#type-t">t</a> * <a href="#type-edge">edge</a>)</span> list</span></span></code></li></ol></div></div><div class="odoc-spec"><div class="spec value anchored" id="val-fold"><a href="#val-fold" class="anchor"></a><code><span><span class="keyword">val</span> fold : <span><span>(<span><a href="#type-node">node</a> <span class="arrow">&#45;&gt;</span></span> <span><a href="#type-node">node</a> <span clas