/**
 * @license
 * Copyright Google LLC All Rights Reserved.
 *
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file at https://angular.io/license
 */
import { Observable } from 'rxjs';
import { CollectionViewer } from './collection-viewer';
export declare abstract class DataSource<T> {
    /**
     * Connects a collection viewer (such as a data-table) to this data source. Note that
     * the stream provided will be accessed during change detection and should not directly change
     * values that are bound in template views.
     * @param collectionViewer The component that exposes a view over the data provided by this
     *     data source.
     * @returns Observable that emits a new value when the data changes.
     */
    abstract connect(collectionViewer: CollectionViewer): Observable<readonly T[]>;
    /**
     * Disconnects a collection viewer (such as a data-table) from this data source. Can be used
     * to perform any clean-up or tear-down operations when a view is being destroyed.
     *
     * @param collectionViewer The component that exposes a view over the data provided by this
     *     data source.
     */
    abstract disconnect(collectionViewer: CollectionViewer): void;
}
/** Checks whether an object is a data source. */
export declare function isDataSource(value: any): value is DataSource<any>;