modifyTQ :: (TimeoutQueue -> TimeoutQueue) -> Mgr ()
modifyTQ f = Mgr $ \s -> do
    let !s' = f s
    return ((), s')
modifyTQ :: (TimeoutQueue -> TimeoutQueue) -> Mgr ()
modifyTQ f = Mgr $ \s -> do
    let !s' = f s
    return ((), s')
modifyTQ f = Mgr $ \s -> do
    let !s' = f s
    return ((), s')