event loop, $(D_PSYMBOL getEventLoop) if not specified.
future to wait for.
can be used to control the maximum time to wait before returning. If $(PARAM timeout) is 0 or negative, block until the future completes.
result of the future. When a timeout occurs, it cancels the task and raises $(D_PSYMBOL TimeoutException). To avoid the task cancellation, wrap it in $(D_SYMBOL shield()).
Wait for the single Future to complete with timeout. If timeout is 0 or negative, block until the future completes.