 class="anchor"></a><code><span><span class="keyword">val</span> dr_b : <span><a href="../../index.html#type-t">t</a> <span class="arrow">&#45;&gt;</span></span> <span><a href="../../index.html#type-t">t</a> <span class="arrow">&#45;&gt;</span></span> <span><a href="../../index.html#type-t">t</a> <span class="arrow">&#45;&gt;</span></span> <span><span><a href="../../index.html#type-t">t</a> <span class="xref-unresolved">Stdlib</span>.ref</span> <span class="arrow">&#45;&gt;</span></span> <a href="../../inde