Class ExecValue

cpp/src/arrow/compute/exec.h:275–329

/// @{

struct ExecValue {
  ArraySpan array = {};
  const Scalar* scalar = NULLPTR;

  ExecValue(const Scalar* scalar)  // NOLINT implicit conversion
      : scalar(scalar) {}

  ExecValue(ArraySpan array)  // NOLINT implicit conversion
      : array(std::move(array)) {}

  ExecValue(const ArrayData& array) {  // NOLINT implicit conversion
    this->array.SetMembers(array);
  }

  ExecValue() = default;
  ExecValue(const ExecValue& other) = default;
  ExecValue& operator=(const ExecValue& other) = default;
  ExecValue(ExecValue&& other) = default;
  ExecValue& operator=(ExecValue&& other) = default;

  int64_t length() const { return this->is_array() ? this->array.length : 1; }

  bool is_array() const { return this->scalar == NULLPTR; }
  bool is_scalar() const { return !this->is_array(); }

  void SetArray(const ArrayData& array) {
    this->array.SetMembers(array);
    this->scalar = NULLPTR;
  }

  void SetScalar(const Scalar* scalar) { this->scalar = scalar; }

  template <typename ExactType>
  const ExactType& scalar_as() const {
    return ::arrow::internal::checked_cast<const ExactType&>(*this->scalar);
  }

  /// XXX: here temporarily for compatibility with datum, see
  /// e.g. MakeStructExec in scalar_nested.cc
  int64_t null_count() const {
    if (this->is_array()) {
      return this->array.GetNullCount();
    } else {
      return this->scalar->is_valid ? 0 : 1;
    }
  }

  const DataType* type() const {
    if (this->is_array()) {
      return array.type;
    } else {
      return scalar->type.get();
    }
  }
};

struct ARROW_EXPORT ExecResult {
  // The default value of the variant is ArraySpan