import * as yup from 'yup';
import { TReferenceProps } from '../../..';
import { IArrayProps, TArrayValidatorResult } from '../_types';
export interface IIsOptionalProps {
}
/**
 * Allow an `array` to be `undefined`.
 */
export declare const isOptional: <T extends yup.AnySchema<any, any, any>>(props?: TReferenceProps<IIsOptionalProps> & Omit<IArrayProps, 'message'>) => TArrayValidatorResult<T, import("../../../i18n/placeholder").IIntlShapeRich>;