Retrieve a std::experimental::future instance for the asynchronous
result associated with *this.
std::experimental::future<ResultType> get_future();
*this
has an associated asynchronous result.
A std::experimental::future instance for the
asynchronous result associated with *this.
An exception of type std::future_error
with an error code of std::future_errc::future_already_retrieved
if a std::experimental::future has already been
obtained for this asynchronous result through a prior call to
get_future().
#include <experimental/future>