Hi,

Quoting the docs for boost::numeric_cast: "There are several situations where conversions are unsafe: [...] Conversions from floating point types to integral types."

What about conversions from integral types to floating point types? E.g. from 64bit int to double.

The following example shows what I mean:

#include <iostream>

#include <cmath>

#include <boost/numeric/conversion/cast.hpp>

int main()

{

const uint64_t i = 123445678911188878;

std::cout << "i=" << i << std::endl;

const double d = i;

std::cout << "d=" << std::fixed << d << std::endl;

std::cout << "next=" << std::fixed << std::nextafter(d, std::numeric_limits<double>::max() ) << std::endl;

std::cout << "prev=" << std::fixed << std::nextafter(d, -std::numeric_limits<double>::max()) << std::endl;

// I'd expect the following cast to fail

const double dd = boost::numeric_cast<double>(i);

std::cout <<"dd=" << std::fixed << dd << std::endl;

return 0;

}

prints

i=123445678911188878

d=123445678911188880.000000

next=123445678911188896.000000

prev=123445678911188864.000000

dd=123445678911188880.000000

because that integer cannot be represented in double precision

Is there something in Boost to help here?

Thanks in advance