import { PipelineOperator } from "../../core";
/**
 * Performs a recursive search on a collection.
 * To each output document, adds a new array field that contains the traversal results of the recursive search for that document.
 *
 * See {@link https://www.mongodb.com/docs/manual/reference/operator/aggregation/graphLookup/ usage}.
 *
 * @param collection
 * @param expr
 * @param options
 * @returns
 */
export declare const $graphLookup: PipelineOperator;
