// who said something and where and when?
static class Source {
  S dialogID;
  boolean master;
  long when;
  S channel, slackTS;
  S line;
  
  *() {}
  
  *(S *line) {
    dialogID = getDialogID();
    master = master();
    when = now();
    channel = getChannelName();
    slackTS = getSlackTS();
  }
}