static WebNode web_stringsToChain(L<S> l) {
  if (empty(l)) null;
  Web web = simpleWeb();
  WebNode first = web.newNode(first(l)), node = first;
  for (int i = 1; i < l(l); i++) {
    WebNode n = web.newNode(l.get(i));
    web_addRelation(node, n, "");
    node = n;
  }
  ret first;
}