std::experimental::packaged_task(concurrencyTS) (3) Linux Manual Page

std::experimental::packaged_task(concurrencyTS) – std::experimental::packaged_task(concurrencyTS)

Synopsis

Defined in header <experimental/future>

template< class > class packaged_task; //not defined (1) (concurrency TS)

template< class R, class ...Args >                   (2) (concurrency TS)

class packaged_task<R(Args...)>;

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>.