Class SparseImpl

cpp/src/arrow/array/diff.cc:792–799

    };

    struct SparseImpl : UnionImpl {
      using UnionImpl::UnionImpl;

      void operator()(const Array& array, int64_t index, std::ostream* os) {
        const auto& union_array = checked_cast<const SparseUnionArray&>(array);
        DoFormat(union_array, index, index, os);
      }
    };

    struct DenseImpl : UnionImpl {
      using UnionImpl::UnionImpl;