import { PersistenceLayerListener } from './PersistenceLayerListener' ; import { PersistenceLayer } from './PersistenceLayer' ; import { Releaseable } from '../reactor/EventListener' ; /**
 * Persistence layer that allows us to listen to changes in the backing store
 * including deletes, updates, and creates of DocMeta and provides details about
 * which files have been updated and their DocInfo.
 */ export interface ListenablePersistenceLayer extends PersistenceLayer { addEventListener ( listener ) : Releaseable ; /**
     * Add an event listener but for a specific document in the repository.
     */ addEventListenerForDoc ( fingerprint , listener ) : void ; }