static void ai_addWebToIndex(MultiMap<S, WebNode> index, Web web) {
  if (web == null) ret;
  for (WebNode node : web_nodesAndRelations(web))
    for (S text : asSet(node.texts())) {
      S key = ai_shortenForIndex(text);
      bool newText;
      synchronized(index) {
        if (key == text) // unchanged by shortening
          newText = true;
        else
          newText = !web_nodesContainText(index.get(key), text);
        index.put(key, node);
      }
      if (newText)
        ai_onNewIndexedText(text);
    }
}