export declare function getStemOfFiles(dir: string): [string[], string[], string[]];
/**
 * Get prefix digits.
 * @param str any string
 * @returns prefix digit, or empty string if fail
 */
export declare function getPrefixDigits(str: string): string;
export declare function getNewStemOfFile(migrationName: string, dir: string, sequential: boolean): string;
export declare function getIndexOfStems(stemOfFiles: readonly string[], version: bigint): number;