ertex</code><code> = string</code></dt></dl><div><div class="spec include"><div class="doc"><dl><dt class="spec value" id="val-compare_vertex"><a href="#val-compare_vertex" class="anchor"></a><code><span class="keyword">val</span> compare_vertex : <a href="index.html#type-vertex">vertex</a> <span>&#45;&gt;</span> <a href="index.html#type-vertex">vertex</a> <span>&#45;&gt;</span> int</code></dt><dt class="spec value" id="val-hash_fold_vertex"><a href="#val-hash_fold_vertex" class="anchor"></a><code><span cla