static Web ai_getWeb(S id) {
  if (!possibleGlobalID(id)) null;
  ret ai_getWeb(asGlobalID(id));
}

static Web ai_getWeb(GlobalID id) {
  if (id == null) null;
  Web web = allWebsByID().getFirst(id);
  if (web != null) ret web;
  
  for (VirtualNodeIndex i : virtualNodeIndices()) {
    web = i.getWeb(id);
    if (web != null) ret web;
  }
  null;
}