Medium blogpost snippet

Autocomplete.swift

func autocomplete(text: Observable<String>) -> (result: Driver<AutocompleteResult>, 
                                                isBusy: Driver<Bool>) {
    let provider = self.provider

    let resultAndLoading: Driver<(result: AutocompleteResult?, loading: Bool)> = text
        .flatMapLatest { query -> Observable<(result: AutocompleteResult?, loading: Bool)> in
            provider
                .autocomplete(text: query)
                .map { (result: .predictions($0), loading: false) }
                .catchError { .just((result: .error($0), loading: false)) }
                .startWith((result: nil, loading: true))
        }
        .asDriver(onErrorJustReturn: (result: .predictions([]), loading: false))

    let result = resultAndLoading
        .flatMap { (result, _) -> Driver<AutocompleteResult> in
            if let result = result {
                return Driver.just(result)
            } else {
                return Driver.empty()
            }
        }

    let isLoading = resultAndLoading
        .flatMap { (_, loading) -> Driver<Bool> in
            return Driver.just(loading)
        }

    return (result: result, isBusy: isLoading)
}