Files
safe_numerics/examples/example11.cpp
Robert Ramey 80e17943ca improved explanation of divide by zero
refined type requirements for integer vs numeric
fixed bugs in safe literal
added acknowledgement to documentation
2017-01-16 12:14:38 -08:00

41 lines
1.2 KiB
C++

#include <cassert>
#include <exception>
#include <iostream>
#include <cstdint>
#include "../include/safe_integer.hpp"
int main(int argc, const char * argv[]){
std::cout << "example 1:";
std::cout << "undetected erroneous expression evaluation" << std::endl;
std::cout << "Not using safe numerics" << std::endl;
// problem: arithmetic operations can yield incorrect results.
try{
std::int8_t x = 127;
std::int8_t y = 2;
std::int8_t z;
// this produces an invalid result !
z = x + y;
std::cout << static_cast<int>(z) << " != " << x + y << std::endl;
std::cout << "error NOT detected!" << std::endl;
}
catch(std::exception){
std::cout << "error detected!" << std::endl;
}
// solution: replace std::int8_t with safe<std::int8_t>
std::cout << "Using safe numerics" << std::endl;
try{
using namespace boost::numeric;
safe<std::int8_t> x = 127;
safe<std::int8_t> y = 2;
safe<std::int8_t> z;
// rather than producing and invalid result an exception is thrown
z = x + y;
}
catch(std::exception & e){
// which can catch here
std::cout << e.what() << std::endl;
}
return 0;
}