 let mobileKey = "mobile"
 
 let discoveredUserSortStyleKey = "discoveredUserSortStyle"
-
 let feedSortStyleKey = "feedSortStyleKey"
 
 struct Listener<T>: Hashable {

        defaults.removeObjectForKey(areaCodeKey)
        defaults.removeObjectForKey(mobileKey)
        defaults.removeObjectForKey(discoveredUserSortStyleKey)
    }

    class func userNeedRelogin() {

        areaCode.removeAllListeners()
        mobile.removeAllListeners()
        discoveredUserSortStyle.removeAllListeners()
        feedSortStyle.removeAllListeners()

        defaults.removeObjectForKey(v1AccessTokenKey)
        defaults.removeObjectForKey(userIDKey)
