/**
 * String Expression Operators: https://docs.mongodb.com/manual/reference/operator/aggregation/#string-expression-operators
 */
import { Options } from '../../../core';
/**
 * Searches a string for an occurrence of a substring and returns the UTF-8 code point index of the first occurence.
 * If the substring is not found, returns -1.
 *
 * @param  {Object} obj
 * @param  {*} expr
 * @return {*}
 */
export declare function $indexOfBytes(obj: object, expr: any, options: Options): any;