import { BaseValidator } from './base';
import type { BooleanValidatorType, ValidationNames } from '../types/index';
export declare function boolean(): BooleanValidator;
export declare class BooleanValidator extends BaseValidator<boolean> implements BooleanValidatorType {
  name: ValidationNames;
  constructor();
  isTrue(): this;
  isFalse(): this;
  custom(fn: (value: boolean) => boolean, message: string): this;
}