Method Impl

cpp/src/arrow/type.cc:2513–2514

 public:
  friend class SchemaBuilder;
  Impl(ConflictPolicy policy, Field::MergeOptions field_merge_options)
      : policy_(policy), field_merge_options_(field_merge_options) {}

  Impl(FieldVector fields, std::shared_ptr<const KeyValueMetadata> metadata,
       ConflictPolicy conflict_policy, Field::MergeOptions field_merge_options)