如何在Swift 2.0中处理掩码(枚举)？

例如,在EventKit中,EKCalendar上有一个名为supportedEventAvailabilities的属性,它的类型为EKCalendarEventAvailabilitymask.它是所有@L_618_2@的事件可用性的掩码.我知道你理论上可以像这样设置它们(如果这个属性是可写的)：

calendar.supportedEventAvailabilities = [.busy,.Free]

但是你怎么再读这些价值呢？我最终得到了这样的代码：

let availabilities = calendar.supportedEventAvailabilities
if (availabilities.rawValue & EKCalendarEventAvailabilitymask.busy.rawvalue) == EKCalendarEventAvailabilitymask.busy.rawValue {
    // 'Busy' is in there!
}
if (availabilities.rawValue & EKCalendarEventAvailabilitymask.Free.rawvalue) == EKCalendarEventAvailabilitymask.Free.rawValue {
    // 'Free' is in there!
}

但这感觉不对.有谁知道如何正确地做到这一点？

let availabilities = calendar.supportedEventAvailabilities
if availabilities.contains(.busy) {
    // 'Busy' is in there!
}

if availabilities.isSupersetOf([.busy,.Free]) {
    // Both .busy and .Free are available ...
}

if availabilities.intersect([.busy,.Free]) != [] {
    // at least one of .busy and .Free is available ...
}