strong> &#8212; called after the signal history is cleared</li>
</ul>
</td>
</tr>
<tr class="field"><th class="field-name">Returns :</th><td class="field-body"><p class="first last">the callback or a blank callback</p>
</td>
</tr>
</tbody>
</table>
</dd></dl>

<dl class="method">
<dt id="Interest">
<tt class="descname">Interest</tt><big>(</big><em>callback</em><span class="optional">[</span>, <em>ignorePast</em><span class="optional">]</span><big>)</big><a class="headerlink" href="#Interest" title="Permalin