ode> (<code class="code">i</code> the index of the key) otherwise<br>
</div>

<pre><span id="VALlookup_exn"><span class="keyword">val</span> lookup_exn</span> : <code class="type">?cmp:'a <a href="Barray_slice.html#TYPEord">ord</a> -> 'a -> 'a <a href="Barray_slice.html#TYPEt">t</a> -> int</code></pre><div class="info ">
Same as <a href="Barray_slice.html#VALlookup_exn"><code class="code">Barray_slice.lookup_exn</code></a>, but<br>
<b>Raises</b> <code>Not_found</code> if the key is not present<br>
</div>

<