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#include <iostream>
#include <cstdint>
#include <boost/safe_numerics/safe_integer.hpp>
using namespace std;
using namespace boost::safe_numerics;
void f(const unsigned int & x, const int8_t & y){
cout << x * y << endl;
}
void safe_f(
const safe<unsigned int> & x,
const safe<int8_t> & y
){
cout << x * y << endl;
}
int main(){
cout << "example 4: ";
cout << "mixing types produces surprising results" << endl;
try {
std::cout << "Not using safe numerics" << std::endl;
// problem: mixing types produces surprising results.
f(100, 100); // works as expected
f(100, -100); // wrong result - unnoticed
cout << "error NOT detected!" << endl;;
}
catch(const std::exception & e){
// never arrive here
cout << "error detected:" << e.what() << endl;;
}
try {
// solution: use safe types
std::cout << "Using safe numerics" << std::endl;
safe_f(100, 100); // works as expected
safe_f(100, -100); // throw error
cout << "error NOT detected!" << endl;;
}
catch(const std::exception & e){
cout << "error detected:" << e.what() << endl;;
}
return 0;
}
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