="tsd-signature-symbol">)</span><span class="tsd-signature-symbol">: </span><a href="LayoutVertex.html" class="tsd-signature-type tsd-kind-class">LayoutVertex</a><a href="#addNode.addNode-1" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24"><use href="../assets/icons.svg#icon-anchor"></use></svg></a></li><li class="tsd-description"><div class="tsd-comment tsd-typography"><p>This convenience method makes sure there is a <a href="LayoutVertex.html" class="tsd-kind-class">LayoutVertex</a>