ss="info ">
<div class="info-desc">
<p>Exception raised whenever an invalid endpoint is used.</p>
</div>
</div>

<pre><span id="TYPE_0"><span class="keyword">type</span> <code class="type"></code>_0</span> </pre>
<div class="info ">
<div class="info-desc">
<p>Empty type.</p>
</div>
</div>


<pre><span id="TYPEst"><span class="keyword">type</span> <code class="type">(+'a, -'b)</code> st</span> </pre>
<div class="info ">
<div class="info-desc">
<p>The type of endpoints for <em>receiving</em> messages of type
