Method Visit

cpp/src/arrow/scalar.cc:896–899

struct MakeNullImpl {
  template <typename T, typename ScalarType = typename TypeTraits<T>::ScalarType>
  enable_if_scalar_constructor_has_arrow_type<T, Status> Visit(const T&) {
    out_ = std::make_shared<ScalarType>(type_);
    return Status::OK();
  }

  template <typename T, typename ScalarType = typename TypeTraits<T>::ScalarType>
  enable_if_scalar_constructor_has_no_arrow_type<T, Status> Visit(const T&) {