从另一个列表中删除项的扩展方法

我正试图基于谓词func筛选列表。我使用func过滤整个列表并返回操作的结果。然后,我需要确定哪些机器出现在完整列表中,而不是筛选列表中。

static void Main(string[] args)
{
    var allActions = new List<MachineAction>
                     {
                         new MachineAction
                             { Name = "A", Status = MachineActionStatus.Cancelled },
                         new MachineAction
                             { Name = "B", Status = MachineActionStatus.Error },
                         new MachineAction
                             { Name = "C", Status = MachineActionStatus.Waiting }
                         };

     var filteredActions = allActions.Where(FilterNotCompleted);
}

private readonly static Func<MachineAction, bool> FilterNotCompleted = action =>
                                         (action.Status == MachineActionStatus.Waiting ||
                                          action.Status == MachineActionStatus.Started);

public class MachineAction
{
    public MachineActionStatus Status { get; internal set; }
    public string Name { get; internal set; }
}

internal enum MachineActionStatus
{
    Waiting,
    Started,
    Success,
    Error,
    Cancelled
} ;

是否有一个扩展方法将完整列表与筛选列表进行比较,并返回不在两者中的列表?

谢谢