Function TransformYield

cpp/src/arrow/util/iterator.h:262–264

template <typename T>
TransformFlow<T> TransformYield(T value = {}, bool ready_for_next = true) {
  return TransformFlow<T>(std::move(value), ready_for_next);
}

template <typename T, typename V>
using Transformer = std::function<Result<TransformFlow<V>>(T)>;