AvdLee

    import Kingfisher
    import ReactiveCocoa
    import enum Result.NoError

    extension KingfisherManager {
        func rac_retrieveImageWithURL(URL: NSURL,
                                  optionsInfo: KingfisherOptionsInfo?,
                                  progressBlock: DownloadProgressBlock?) -> SignalProducer<(image: UIImage?, cacheType: CacheType, imageURL: NSURL?), NSError> {
            return SignalProducer { observer, disposable in