/a></span></code></div><div class="spec-doc"><p>Transitive closure of <code>preds</code>. <code>preds_hat s q</code> returns all the predecessors (immediate or not) of <code>q</code> in <code>s</code></p></div></div><div class="odoc-spec"><div class="spec value anchored" id="val-attr_of"><a href="#val-attr_of" class="anchor"></a><code><span><span class="keyword">val</span> attr_of : <span><a href="#type-t">t</a> <span class="arrow">&#45;&gt;</span></span> <span><a href="#type-state">state</a> <span class="a