static L<Pair<WebNode>> chatHistory_peepHole_nodePairs() {
  ILister lister = persistentListerReadOnly(chatTheoryModule());
  L<S> msgs = lister.getList('globalIDList);
  Map<S, Web> webs = lister.getHashMap('theoryForLineMap);
  //print("Have " + n(countNotNull(msgs), "msg") + ", " + n(webs, "web"));

  new L<Pair<WebNode>> nodePairs;
  
  for (int i = 1; i+1 < l(msgs); i++) {
    S id1 = msgs.get(i), id2 = msgs.get(i+1);
    if (id1 == null || id2 == null) continue;
    Web a = webs.get(id1);
    Web b = webs.get(id2);
    if (a == null || b == null) {
      print("Missing webs at " + i);
      continue;
    }
    //print("Have " + web_firstNode(a));
    nodePairs.add(pair(web_firstNode(a), web_firstNode(b)));
  }
  
  ret nodePairs;
}