static class SlackMsg {

  S user, botName; // one of these is going to be set

  S userName; // looked up if user != null

  S type, text, ts;

  O reactions;

  S channelID;

}

static L<SlackMsg> slackReadChannel(S channelID, S token, int limit) {

  ret slackReadChannel(channelID, token, limit, null);

}

static L<SlackMsg> slackReadChannel(S channelID, S token, int limit, S oldest) {

  S url = "https://slack.com/api/channels.history";

  S postData = "token=" + urlencode(token) + "&channel=" + urlencode(channelID) + "&count=" + limit

    + (oldest != null ? "&oldest=" + urlencode(oldest) : "");

  S data = doPostWithTimeout(postData, url, slackSetTimeout_get());

  Map map = cast jsonDecode(data);

  if (!isTrue(map.get("ok")))

    fail(structure(map));

  List<Map> _msgs = cast map.get("messages");

  new L<SlackMsg> msgs;

  for (Map msg : reversedList(_msgs)) {

    new SlackMsg m;

    m.type = (S) msg.get("type");

    m.user = (S) msg.get("user");

    m.botName = (S) msg.get("username");

    m.text = htmldecode((S) msg.get("text"));

    m.ts = (S) msg.get("ts");

    m.reactions = msg.get("reactions");

    m.channelID = channelID;

    m.userName = slackGetUserName(token, m.user);

    msgs.add(m);

    //print(structure(m));

  }

  //print(l(msgs) + " messages sucked from slack channel.");

  ret msgs;

}