Function CastImpl

cpp/src/arrow/scalar.cc:1095–1099

// error fallback
template <typename To>
Result<std::shared_ptr<Scalar>> CastImpl(const Scalar& from,
                                         std::shared_ptr<DataType> to_type) {
  return Status::NotImplemented("casting scalars of type ", *from.type, " to type ",
                                *to_type);
}

// numeric to numeric
template <typename To, typename From>