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std::packaged_task<R(Args...)>::reset

From cppreference.com
 
 
Concurrency support library
Threads
(C++11)
(C++20)
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this_thread namespace
(C++11)
(C++11)
(C++11)
Mutual exclusion
(C++11)
(C++11)  
Generic lock management
(C++11)
(C++11)
(C++11)
(C++11)(C++11)(C++11)
(C++11)
(C++11)
Condition variables
(C++11)
Semaphores
Latches and Barriers
(C++20)
(C++20)
Futures
(C++11)
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Safe Reclamation
(C++26)
(C++26)
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Atomic types
(C++11)
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Initialization of atomic types
(C++11)(deprecated in C++20)
(C++11)(deprecated in C++20)
Memory ordering
Free functions for atomic operations
Free functions for atomic flags
 
 
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.

Contents

[edit] Parameters

(none)

[edit] Return value

(none)

[edit] Exceptions

[edit] Example

#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