 class="type-var">'b</span>)</span> <span>&#45;&gt;</span> <span><span class="type-var">'a</span> <a href="../Extend/index.html#type-t">Extend.t</a></span> <span>&#45;&gt;</span> <span><span class="type-var">'b</span> <a href="../Extend/index.html#type-t">Extend.t</a></span></code></dt><dt class="spec value" id="val-(=&gt;&gt;)"><a href="#val-(=&gt;&gt;)" class="anchor"></a><code><span class="keyword">val</span> (=&gt;&gt;) : <span><span class="type-var">'a</span> <a href="../Extend/index.html#type-t">Exten