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#include <stdexcept>
#include <iostream>
#include <boost/safe_numerics/safe_integer.hpp>
int main(int, const char *[]){
// problem: cannot recover from arithmetic errors
std::cout << "example 8: ";
std::cout << "cannot detect compile time arithmetic errors" << std::endl;
std::cout << "Not using safe numerics" << std::endl;
try{
const int x = 1;
const int y = 0;
// will emit warning at compile time
// will leave an invalid result at runtime.
std::cout << x / y; // will display "0"!
std::cout << "error NOT detected!" << std::endl;
}
catch(const std::exception &){
std::cout << "error detected!" << std::endl;
}
// solution: replace int with safe<int>
std::cout << "Using safe numerics" << std::endl;
try{
using namespace boost::safe_numerics;
const safe<int> x = 1;
const safe<int> y = 0;
// constexpr const safe<int> z = x / y; // note constexpr here!
std::cout << x / y; // error would be detected at runtime
std::cout << " error NOT detected!" << std::endl;
}
catch(const std::exception & e){
std::cout << "error detected:" << e.what() << std::endl;
}
return 0;
}
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