src/http/get-index/ssr.js
/**
   * @param {string} localName the custom element definition name
   */
@param {string} localName the custom element definition name
@param { string } localName the custom element definition name
whenDefined(localName) {
    const { registry, waiting } = this;
    return new Promise((resolve) => {
      if (registry.has(localName))
      resolve(registry.get(localName).Class);else
      {
        if (!waiting.has(localName))
        waiting.set(localName, []);
        waiting.get(localName).push(resolve);
      }
    });
  }
whenDefined ( localName ) { const { registry , waiting } = this ; return new Promise ( ( resolve ) => { if ( registry . has ( localName ) ) resolve ( registry . get ( localName ) . Class ) ; else { if ( ! waiting . has ( localName ) ) waiting . set ( localName , [ ] ) ; waiting . get ( localName ) . push ( resolve ) ; } } ) ; }
@param {string} localName the custom element definition name
@param { string } localName the custom element definition name