Method run_if_is_deferred

extern/boost/boost/thread/future.hpp:2213–2215

            static_cast<base_type*>(this)->swap(other);
        }
        bool run_if_is_deferred() {
          return this->future_->run_if_is_deferred();
        }
        bool run_if_is_deferred_or_ready() {
          return this->future_->run_if_is_deferred_or_ready();
        }