A future The future class represents the result of an asynchronous computation. Creates a null future. const future<T> & Creates a new future object as a copy of other. const future<T> & Copies the future from other. Destroys the future object. T Returns the result stored in the future. This will block until the computation is completed and the result is ready. bool Returns true if the future is valid. void Blocks until the asynchronous computation is complete. event Returns the event associated with the future.