code: func (ch *channel) addNick(nk *nick, cp *ChanPrivs) {
  	if _, ok := ch.nicks[nk]; !ok {
  		ch.nicks[nk] = cp
  		ch.lookup[nk.nick] = nk
  	} else {
  		logging.Warn("Channel.addNick(): %s already on %s.", nk.nick, ch.name)
  	}
  }
docs: // Associates a Nick with a Channel