util

type WorkerPool interface {
	// Submit queues a function for execution
	// in a separate routine.
	//
	// Implementation must return any error encountered
	// that prevented the function from being queued.
	Submit(func()) error

	// Release releases worker pool resources. All `Submit` calls will
	// finish with ErrPoolClosed. It doesn't wait until all submitted
	// functions have returned so synchronization must be achieved
	// via other means (e.g. sync.WaitGroup).
	Release()

	// Tune changes the capacity of this pool.
	Tune(int)
}