import type { ValuesOf } from '@naturalcycles/js-lib';
import 'dotenv/config';
/**
 * @example
 *
 * const {a, b} = requreEnvKeys(['a', 'b'])
 *
 * Will throw if any of the passed keys is not defined.
 */
export declare function requireEnvKeys<T extends readonly string[]>(...keys: T): {
    [k in ValuesOf<T>]: string;
};
export declare function requireFileToExist(filePath: string): void;