// slurp whole channel at once

static L<SlackMsg> multiSlurp(S channelName, S token) {
  ret multiSlurp(channelName, token, null, null);
}

// inclusive is always false
// slurp a part of the channel (everything > oldest and < latest)
// channelName can also by the ID (starting with "C")

static L<SlackMsg> multiSlurp(S channelName, S token, S oldest, S latest) {
  S channelID = channelName;
  if (!channelName.startsWith("C")) {
    Map<S, S> channels = slackGetChannelIDs(token);
    channelName = dropPrefix("#", channelName);
    channelID = channels.get(channelName);
  }
  if (channelID == null) fail("Channel not found: " + channelName);
  int limit = 1000;
  L<SlackMsg> l;
  new L<L<SlackMsg>> all;
  int n = 0; // safety switch #1 - never suck more than 100.000 msgs
  do {
    l = slackSlurp(channelID, token, limit, oldest, latest, false);
    if (empty(l)) break;
    S newLatest = first(l).ts;
    assertNotNull(newLatest);
    
    // safety switch #2
    if (latest != null) assertTrue(cmp(latest, newLatest) > 0);
    
    latest = newLatest;
    print("latest=" + latest);
    print(l(l) + " messages slurped from #" + channelName);
    all.add(l);
  } while (++n < 100);
  ret concatLists(reversedList(all));
}

Began life as a copy of #1002173