import { Invalid, Valid, Validator } from "../models/validators";
export declare const not: <T>(validator: Validator<T>, reason?: string) => Validator<unknown>;
export declare const both: <T, U>(first: Validator<T>, second: Validator<U>) => Validator<T & U>;
export declare const either: <T, U>(first: Validator<T>, second: Validator<U>) => Validator<T | U>;
export declare const optional: <T>(validator: Validator<T>) => Validator<T | undefined>;
export declare const chain: <T, U>(first: Validator<T>, second: Validator<U>) => (input: unknown) => Invalid<T> | Invalid<U> | Valid<U>;