StandardPair.swift

struct StandardPair<T> {
    let key: String
    
    var value: T? {
        set {
            if let safeValue = newValue {
                UserDefaults.standard.set(safeValue, forKey: key)
            } else {
                UserDefaults.standard.removeObject(forKey: key)
            }
        }
        get {
            return UserDefaults.standard.object(forKey: key) as? T
        }
    }
}