NAME¶

std::packaged_task::reset - std::packaged_task::reset

Synopsis¶

void reset(); (since C++11)

Resets the state abandoning the results of previous executions. New shared state is
constructed.

Equivalent to *this = packaged_task(std::move(f)), where f is the stored task.

Parameters¶

(none)

Return value¶

(none)

Exceptions¶

* std::future_error if *this has no shared state. The error condition is set to
no_state.
* std::bad_alloc if there was not enough memory for a new shared state.
* Any exception thrown by the move constructor of the new packaged_task.

Example¶

// Run this code

#include <cmath>
#include <future>
#include <iostream>
#include <thread>

int main()
{
std::packaged_task<int(int,int)> task([](int a, int b)
{
return std::pow(a, b);
});
std::future<int> result = task.get_future();
task(2, 9);
std::cout << "2^9 = " << result.get() << '\n';

task.reset();
result = task.get_future();
std::thread task_td(std::move(task), 2, 10);
task_td.join();
std::cout << "2^10 = " << result.get() << '\n';
}

Output:¶

2^9 = 512
2^10 = 1024