on *:TEXT:!setcw *:#:{
  if ($nick isop #) || ($nick ishop #) && ($$2 isnum) {
    set %cw $2-
    msg $chan cw world has been changed, !cw for new world 
    else { halt }
  }
}

on *:TEXT:!cw:#:{
  notice $nick The current world is %cw $+ .
}