src/boost/libs/safe_numerics/example/example19.cpp


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#include <type_traits>
#include <boost/safe_numerics/safe_integer.hpp>
#include <boost/safe_numerics/safe_integer_range.hpp>

#include <boost/safe_numerics/utility.hpp>

using namespace boost::safe_numerics;

void f(){
    safe_unsigned_range<7, 24> i;
    // since the range is included in [0,255], the underlying type of i 
    // will be an unsigned char.
    i = 0;  // throws out_of_range exception
    i = 9;  // ok
    i *= 9; // throws out_of_range exception
    i = -1; // throws out_of_range exception
    std::uint8_t j = 4;
    auto k = i + j;

    // if either or both types are safe types, the result is a safe type
    // determined by promotion policy.  In this instance
    // the range of i is [7, 24] and the range of j is [0,255].
    // so the type of k will be a safe type with a range of [7,279]
    static_assert(
        is_safe<decltype(k)>::value
        && std::numeric_limits<decltype(k)>::min() == 7
        && std::numeric_limits<decltype(k)>::max() == 279,
        "k is a safe range of [7,279]"
    );
}

int main(){}