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#ifndef RFL_PARSING_TABULAR_MAKECHUNKEDARRAYITERATORS_HPP_
#define RFL_PARSING_TABULAR_MAKECHUNKEDARRAYITERATORS_HPP_
#include <arrow/api.h>
#include <array>
#include <cinttypes>
#include <memory>
#include <optional>
#include <stdexcept>
#include <string>
#include <type_traits>
#include "../../NamedTuple.hpp"
#include "../../Ref.hpp"
#include "../../Result.hpp"
#include "../../Tuple.hpp"
#include "ChunkedArrayIterator.hpp"
namespace rfl::parsing::tabular {
template <class NamedTupleType, SerializationType _s>
struct MakeChunkedArrayIterators;
template <SerializationType _s, class... FieldTypes>
struct MakeChunkedArrayIterators<NamedTuple<FieldTypes...>, _s> {
using TupleType =
Tuple<ChunkedArrayIterator<typename FieldTypes::Type, _s>...>;
Result<TupleType> operator()(const Ref<arrow::Table>& _table) const {
const auto get_column =
[&](const std::string& _colname) -> Result<Ref<arrow::ChunkedArray>> {
const auto col = _table->GetColumnByName(_colname);
if (!col) {
return error("Column named '" + _colname + "' not found.");
}
return Ref<arrow::ChunkedArray>::make(col);
};
try {
return TupleType(
get_column(typename FieldTypes::Name().str())
.transform(
ChunkedArrayIterator<typename FieldTypes::Type, _s>::make)
.value()...);
} catch (const std::exception& e) {
return error(e.what());
}
}
};
template <class NamedTupleType, SerializationType _s>
const auto make_chunked_array_iterators =
MakeChunkedArrayIterators<NamedTupleType, _s>{};
} // namespace rfl::parsing::tabular
#endif
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