Propertywrapper for UserDefaults in Swift

Propertywrapper.swift

private protocol AnyOptional{
    var isNil: Bool { get }
}

extension Optional: AnyOptional{
    var isNil: Bool { self == nil }
}

@propertyWrapper
struct UserDefaultsWrapper<T> {
    let key: String
    let defaultValue: T
    let userDefaults: UserDefaults = .standard
    
    var wrappedValue: T {
        get {
            return userDefaults.object(forKey: key) as? T ?? defaultValue
        }
        set {
            if let optional = newValue as? AnyOptional, optional.isNil {
               UserDefaults.standard.removeObject(forKey: key)
            }else{
                userDefaults.set(newValue, forKey: key)
            }
        }
    }
}


struct UserDefaultsConfig{
    @UserDefaultsWrapper(key: "com.user.session", defaultValue: false)
    static var sessionStarted: Bool
    
    @UserDefaultsWrapper(key: "com.user.details", defaultValue: [:])
    static var userDetails: [String: String]
}


//Saving values
UserDefaultsConfig.sessionStarted = true
print(UserDefaultsConfig.sessionStarted)

UserDefaultsConfig.userDetails = ["userName": "Anand", "country": "India"]
print(UserDefaultsConfig.userDetails)

//Resetting values
UserDefaultsConfig.sessionStarted = false
UserDefaultsConfig.userDetails = [:]