c++ - Is it safe to return from function before all std::futures are finished? -

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i have code that:

int function() {     std::vector<std::future<int>> futures;     (const auto& elem : elements)     {         futures.push_back(std::async(&myclass::foo, myclass, elem);     }     (auto& f : futures)     {         const int x = f.get();         if (x != 0)             return x;     } }

can return function when there unfinished async calls? i'm interested in 1 non 0 value. should wait until async calls finished? code safe?

the destructor of std::future (when initialized call std::async) blocks until async task complete. (see here)

so function return statement not complete until of tasks have finished.


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