Double_wrapper vc++, C++ (vc++)

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#include <boost/serialization/split_member.hpp>
#include <boost/serialization/wrapper.hpp>
#include <boost/serialization/tracking.hpp>
#include <limits>
#include <cmath>

#include <boost/archive/tmpdir.hpp>
#include <boost/archive/text_iarchive.hpp>
#include <boost/archive/text_oarchive.hpp>
#include <fstream>
#include <iostream>

class Double_wrapper {

private:
    enum double_type {DT_NONE, DT_NAN, DT_INF, DT_NINF};

double& value;

public:
    Double_wrapper(double& val):value(val){}
    Double_wrapper(Double_wrapper const& rhs):value(rhs.value) {}

private:
    friend class boost::serialization::access;
    template<class Archive>
    void save(Archive & ar, const unsigned int) const {
        double_type flag = DT_NONE;
        double val = value;

if (!std::isfinite(val)) {
            if (std::isnan(val))    {
                flag = DT_NAN;
            } else if (val > 0) {
                flag = DT_INF;
            } else {
                flag = DT_NINF;
            }
            val = 0;
        }

ar & val;
        ar & flag;
    }
    template<class Archive>
    void load(Archive & ar, const unsigned int) const {
        double_type flag;

ar & value;
        ar & flag;

switch (flag) {
            case DT_NONE:   break;
            case DT_NAN:    value = std::numeric_limits<double>::quiet_NaN(); break;
            case DT_INF:    value = std::numeric_limits<double>::infinity(); break;
            case DT_NINF:   value = -std::numeric_limits<double>::infinity();
        }
    }

BOOST_SERIALIZATION_SPLIT_MEMBER()
};

BOOST_CLASS_IS_WRAPPER(Double_wrapper)
BOOST_CLASS_TRACKING(Double_wrapper, boost::serialization::track_never)

///////////////////////////////////////////////////////////////////////////////////////

class MyClass {

public:
    double value;

template <class Archive>
    void serialize(Archive &ar, const unsigned int){
        Double_wrapper dw(value);
        ar & dw;
    }
};

///////////////////////////////////////////////////////////////////////////////////////

int main() {

MyClass tmp;
    tmp.value = std::numeric_limits<double>::quiet_NaN();

std::cout << "value=" << tmp.value << std::endl;

std::string filename(boost::archive::tmpdir());
    filename += "/tmp.txt";

//Output
    std::ofstream ofs(filename.c_str(), std::ios_base::out);
    boost::archive::text_oarchive oar(ofs);
    oar << tmp;

ofs.close();

//Input
    MyClass newtmp;
    std::ifstream ifs(filename.c_str(), std::ios_base::in);
    boost::archive::text_iarchive iar(ifs);
    iar >> newtmp;

std::cout << "value=" << newtmp.value << std::endl;

}

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Compilation time: 3,16 sec, absolute running time: 0,22 sec, absolute service time: 3,39 sec