std::packaged_task<R(Args...)>::reset
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std::packaged_task
Member functions
Getting the result
Execution
packaged_task::reset
Non-member functions
Helper classes
(until C++17)
Deduction guides (C++17)
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
- 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.
[edit] 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