Constructs a new std::experimental::shared_future instance and transfers
ownership of the asynchronous result associated with *this to this newly constructed std::experimental::shared_future instance.
shared_future<ResultType> share();
As-if shared_future<ResultType>(std::move(*this)).
The asynchronous result associated with *this prior to the invocation of
share()
(if any) is associated with the newly constructed std::experimental::shared_future instance.
this->valid()
returns false.
Nothing.
#include <experimental/future>