var">'b</span> option</span> Lwt.t</span></code></dt><dt class="spec value" id="val-sendNativeMessage"><a href="#val-sendNativeMessage" class="anchor"></a><code><span class="keyword">val</span> sendNativeMessage : <span>?&#8288;callback:<span>(<span><span class="type-var">'a</span> <a href="../../../ezjs-min/Js_min/index.html">Js_min</a>.t</span> <span>&#45;&gt;</span> <span class="type-var">'b</span>)</span></span> <span>&#45;&gt;</span> string <span>&#45;&gt;</span> <span><span class="type-var">'c</span> 