import { BaseError } from 'make-error';
import { Constrained } from '../../core';
export declare class InvalidSHA1Error extends BaseError {
    constructor();
}
export declare const sha1Symbol: unique symbol;
export type SHA1 = Constrained<typeof sha1Symbol, string>;
export declare function isSHA1(input: unknown): input is SHA1;
export declare function sha1(input: unknown): SHA1;