csv_policies.h

Go to the documentation of this file.

/**************************************************************************
Copyright: (C) 2025 Alexander Shaduri
License: Zlib
***************************************************************************/
 
#ifndef CSV_POLICIES_H
#define CSV_POLICIES_H
 
#include "csv_cell.h"  // CellTypeHint
 
#include <optional>
#include <string_view>
#include <type_traits>
#include <limits>
 
 
namespace Csv {
 
 
struct LocaleAwareBehaviorPolicy {
 
    [[nodiscard]] static constexpr bool useEmptyCellType() noexcept
    {
        return true;
    }
 
 
    template<typename Number>
    static std::optional<Number> readNumber(std::string_view cell)
    {
        return readNumberLocale<Number>(cell);
    }
 
 
    template<typename CellT>
    static constexpr CellT create(std::string_view cell, CellTypeHint hint)
    {
        // The types here are the same as in readNumber()
        if constexpr(std::is_arithmetic_v<CellT>) {
            // quiet_NaN() returns 0 for integral types
            return LocaleAwareBehaviorPolicy::readNumber<CellT>(cell)
                    .value_or(std::numeric_limits<CellT>::quiet_NaN());
        } else {
            // Cell* classes
            return CellT{cell, hint, LocaleAwareBehaviorPolicy{}};
        }
    }
};
 
 
 
struct LocaleUnawareBehaviorPolicy {
 
    [[nodiscard]] static constexpr bool useEmptyCellType() noexcept
    {
        return true;
    }
 
 
    template<typename Number>
    static constexpr std::optional<Number> readNumber(std::string_view cell)
    {
        return readNumberNoLocale<Number>(cell);
    }
 
 
    template<typename CellT>
    static constexpr CellT create(std::string_view cell, CellTypeHint hint)
    {
        // The types here are the same as in readNumber()
        if constexpr(std::is_arithmetic_v<CellT>) {
            // quiet_NaN() returns 0 for integral types
            return LocaleUnawareBehaviorPolicy::readNumber<CellT>(cell)
                    .value_or(std::numeric_limits<CellT>::quiet_NaN());
        } else {
            // Cell* classes
            return CellT{cell, hint, LocaleUnawareBehaviorPolicy{}};
        }
    }
};
 
 
 
}  // end ns
 
 
 
#endif