src/boost/libs/safe_numerics/example/example83.cpp


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#include <iostream>

#include <boost/safe_numerics/safe_integer_range.hpp>
#include <boost/safe_numerics/safe_integer_literal.hpp>
#include <boost/safe_numerics/exception.hpp>
#include <boost/safe_numerics/native.hpp>
#include "safe_format.hpp" // prints out range and value of any type

using namespace boost::safe_numerics;

// create a type for holding small integers in a specific range
using safe_t = safe_signed_range<
    -24,
    82,
    native,           // C++ type promotion rules work OK for this example
    loose_trap_policy // catch problems at compile time
>;

// create a type to hold one specific value
template<int I>
using const_safe_t = safe_signed_literal<I, native, loose_trap_policy>;

// We "know" that C++ type promotion rules will work such that
// addition will never overflow. If we change the program to break this,
// the usage of the loose_trap_policy promotion policy will prevent compilation.
int main(int, const char *[]){
    std::cout << "example 83:\n";

    constexpr const const_safe_t<10> x;
    std::cout << "x = " << safe_format(x) << std::endl;
    constexpr const const_safe_t<67> y;
    std::cout << "y = " << safe_format(y) << std::endl;
    const safe_t z = x + y;
    std::cout << "x + y = " << safe_format(x + y) << std::endl;
    std::cout << "z = " << safe_format(z) << std::endl;
    return 0;
}