spec value anchored" id="val-iter"><a href="#val-iter" class="anchor"></a><code><span><span class="keyword">val</span> iter : <span><span>(<span><a href="#type-key">key</a> <span class="arrow">&#45;&gt;</span></span> <span><span class="type-var">'a</span> <span class="arrow">&#45;&gt;</span></span> unit)</span> <span class="arrow">&#45;&gt;</span></span> <span><span><span class="type-var">'a</span> <a href="#type-t">t</a></span> <span class="arrow">&#45;&gt;</span></span> unit</span></code></div></div><div 