d="val-ln"><a href="#val-ln" class="anchor"></a><code><span class="keyword">val</span> ln : <a href="index.html#type-t">t</a> <span>&#45;&gt;</span> <span><a href="index.html#type-t">t</a> option</span></code></dt><dt class="spec value" id="val-exp"><a href="#val-exp" class="anchor"></a><code><span class="keyword">val</span> exp : <a href="index.html#type-t">t</a> <span>&#45;&gt;</span> <span>(<a href="index.html#type-kind">kind</a> * <a href="B/index.html#type-t">B.t</a>)</span> * <span>(<a href="index.htm