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// promise::set_exception
#include <iostream> // std::cin, std::cout, std::ios
#include <functional> // std::ref
#include <thread> // std::thread
#include <future> // std::promise, std::future
#include <exception> // std::exception, std::current_exception
void get_int (std::promise<int>& prom) {
int x;
std::cout << "Please, enter an integer value: ";
std::cin.exceptions (std::ios::failbit); // throw on failbit
try {
std::cin >> x; // sets failbit if input is not int
prom.set_value(x);
}
catch (std::exception&) {
prom.set_exception(std::current_exception());
}
}
void print_int (std::future<int>& fut) {
try {
int x = fut.get();
std::cout << "value: " << x << '\n';
}
catch (std::exception& e) {
std::cout << "[exception caught: " << e.what() << "]\n";
}
}
int main ()
{
std::promise<int> prom;
std::future<int> fut = prom.get_future();
std::thread th1 (print_int, std::ref(fut));
std::thread th2 (get_int, std::ref(prom));
th1.join();
th2.join();
return 0;
}
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