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// Copyright (c) 2018Robert Ramey
//
// Distributed under the Boost Software License, Version 1.0. (See
// accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
#include <iostream>
#include <boost/safe_numerics/safe_integer.hpp>
int main(){
std::cout << "example 4: ";
std::cout << "implicit conversions change data values" << std::endl;
std::cout << "Not using safe numerics" << std::endl;
// problem: implicit conversions change data values
try{
signed int a{-1};
unsigned int b{1};
std::cout << "a is " << a << " b is " << b << '\n';
if(a < b){
std::cout << "a is less than b\n";
}
else{
std::cout << "b is less than a\n";
}
std::cout << "error NOT detected!" << std::endl;
}
catch(const std::exception &){
// never arrive here - just produce the wrong answer!
std::cout << "error detected!" << std::endl;
return 1;
}
// solution: replace int with safe<int> and unsigned int with safe<unsigned int>
std::cout << "Using safe numerics" << std::endl;
try{
using namespace boost::safe_numerics;
safe<signed int> a{-1};
safe<unsigned int> b{1};
std::cout << "a is " << a << " b is " << b << '\n';
if(a < b){
std::cout << "a is less than b\n";
}
else{
std::cout << "b is less than a\n";
}
std::cout << "error NOT detected!" << std::endl;
return 1;
}
catch(const std::exception & e){
// never arrive here - just produce the correct answer!
std::cout << e.what() << std::endl;
std::cout << "error detected!" << std::endl;
}
return 0;
}
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