Method key

cpp/fory/meta/field_info.h:249–251

    return with_spec(spec_.map(key, value));
  }
  constexpr FieldMeta key(FieldNodeSpec key_spec) const {
    return with_spec(spec_.key(key_spec));
  }
  constexpr FieldMeta value(FieldNodeSpec value_spec) const {
    return with_spec(spec_.value(value_spec));
  }