/**
   * Flattens a deeply nested array.
   * @example
   * const flatArray = flatten(nestedArray, 'subItems');
*/
export declare const flatten: (nestedRoutes: any, subItemKey: any, pushParents: any, appendIndices: any) => any[];
/**
   * Comparer function for use in a native JavaScript `sort` function. Will perform a basic
   * sort basked on a provided `sortField` parameter.
   * @example
   * const sortedArray = myArray.sort(by('someFieldName'));
*/
export declare const by: (sortField: string) => (a: any, b: any) => 0 | 1 | -1;