future-blog-post-7

future2.go

// Interface represents a future. No concrete implementation is
// exposed; all access to a future is via this interface.
type Interface interface {
	// Get returns the values calculated by the future. It will pause until
	// the value is calculated.
	//
	// If Get is invoked multiple times, the same value will be returned each time.
	// Subsequent calls to Get will return instantaneously.
	Get() (interface{}, error)

	// GetUntil waits for up to Duration d for the future to complete. If the
	// future completes before the Duration completes, the value and error are returned
	// and timeout is returned as false. If the Duration completes before the future
	// returns, nil is returned for the value and the error and timeout is returned
	// as true.
	GetUntil(d time.Duration) (interface{}, bool, error)
}