std::experimental::packaged_task (concurrency TS)
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                    This page is about the modified version of std::packaged_task provided by the concurrency TS supporting the std::future improvements made by that TS. For the version of packaged_task with type-erased allocator support provided by the Library Fundamentals TSes, see std::experimental::fundamentals_v2::packaged_task.
|   Defined in header  <experimental/future>
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|   template< class > class packaged_task; //not defined  | 
(1) | (concurrency TS) | 
|   template< class R, class ...Args >  class packaged_task<R(Args...)>;  | 
(2) | (concurrency TS) | 
std::experimental::concurrency_v1::packaged_task is a modified version of std::packaged_task provided by the concurrency TS that works with std::experimental::future.
The only change from std::packaged_task is that the get_future() member function returns a std::experimental::future<R>.