/**
 * @file Locale-aware + numeric-aware comparison via `Intl.Collator`, plus the
 *   `naturalSorter` helper that wires the fast-sort engine to the natural
 *   comparator. Collator instances are lazy-created and cached because `new
 *   Intl.Collator()` is 10-14ms in Node — too expensive to call
 *   per-comparison.
 */
import type { FastSortFunction } from './types';
/**
 * Compare two strings using locale-aware comparison.
 *
 * @example
 *   ;```typescript
 *   localeCompare('a', 'b') // -1
 *   localeCompare('b', 'a') // 1
 *   localeCompare('a', 'a') // 0
 *   ```
 */
export declare function localeCompare(x: string, y: string): number;
/**
 * Compare two strings using natural sorting (numeric-aware, case-insensitive).
 *
 * @example
 *   ;```typescript
 *   naturalCompare('file2', 'file10') // negative (file2 before file10)
 *   naturalCompare('img10', 'img2') // positive (img10 after img2)
 *   ```
 */
export declare function naturalCompare(x: string, y: string): number;
/**
 * Sort an array using natural comparison.
 *
 * @example
 *   ;```typescript
 *   naturalSorter(['file10', 'file2', 'file1']).asc()
 *   // ['file1', 'file2', 'file10']
 *   ```
 */
export declare function naturalSorter<T>(arrayToSort: T[]): ReturnType<FastSortFunction>;
