ss tsd-is-overwrite tsd-is-inherited">
						<li class="tsd-signature tsd-kind-icon">once<span class="tsd-signature-symbol">(</span>event<span class="tsd-signature-symbol">: </span><span class="tsd-signature-type">string</span><span class="tsd-signature-symbol"> | </span><span class="tsd-signature-type">symbol</span>, listener<span class="tsd-signature-symbol">: </span><span class="tsd-signature-type">function</span><span class="tsd-signature-symbol">)</span><span class="tsd-signature-symbol">: </span><span