Method Get

cpp/src/arrow/type.cc:1810–1834

  template <typename Selector, typename T = typename Selector::ArrowType>
  static Result<std::shared_ptr<T>> Get(const FieldPath* path, Selector selector,
                                        int* out_of_range_depth = nullptr) {
    if (path->empty()) {
      return Status::Invalid("empty indices cannot be traversed");
    }

    int depth = 0;
    for (auto index : *path) {
      ARROW_ASSIGN_OR_RAISE(auto next_selector, selector.GetChild(index));

      // Handle failed bounds check
      if (!next_selector) {
        if (out_of_range_depth) {
          *out_of_range_depth = depth;
          return nullptr;
        }
        return IndexError(path, depth, selector);
      }

      selector = std::move(next_selector);
      ++depth;
    }

    return selector.Finish();
  }
};

Result<std::shared_ptr<Field>> FieldPath::Get(const Schema& schema) const {