Functions to Observable Wrapper

fn+rx.swift

func reactivex<I, O>(_ f: @escaping (I) -> O) -> (I) -> Observable<O> {
    return { input in
        return Observable.create { emitter in
            emitter.onNext(f(input))
            emitter.onCompleted()
            return Disposables.create()
        }
    }
}

func reactivex<I, O>(_ f: @escaping (I, @escaping (O) -> Void) -> Void) -> (I) -> Observable<O> {
    return { i in
        return Observable.create { emitter in
            f(i, { o in
                emitter.onNext(o)
                emitter.onCompleted()
            })
            return Disposables.create()
        }
    }
}