import type { Result } from './result.js';
type ExpectErr = {
    <Res extends Result.Any>(msg: string): (res: Res) => Result.ErrType<Res>;
    <Res extends Result.Any>(msg: string, res: Res): Result.ErrType<Res>;
};
/**
 * Unwrap an expected `Err` value from a `Result`, or throw if it is an `Ok`.
 *
 * @tags result, unwrap, errors, unsafe
 * @see https://doc.rust-lang.org/core/result/enum.Result.html#method.expect_err
 */
export declare const expectErr: ExpectErr;
export {};