p><span class="term">Returns:</span></p></td>
<td><p><code class="computeroutput">true</code> if no slots
            are connected to the signal, and
            <code class="computeroutput">false</code> otherwise.</p></td>
</tr>
<tr>
<td><p><span class="term">Throws:</span></p></td>
<td><p>Will not throw.</p></td>
</tr>
<tr>
<td><p><span class="term">Complexity:</span></p></td>
<td><p>Linear in the number of slots known to the
            signal.</p></td>
</tr>
<tr>
<td><p><span class="term">Rationale:</s