import { Document } from "mongodb";
export type CollectionMap = {
    [key: string]: string;
};
/**
 * Get a MongoDB lookup stage based on oData expand parameter
 * @param expr expression of the oData expand parameter
 * @param collectionMap collection map to map properties of a data model to collection names
 * @returns MongoDB lookup stage
 */
export declare function generateLookupFromExpand(expr: string, collectionMap: CollectionMap): Document[];