import { When } from './base';
/** A type alias for a validator function */
export declare type TValidator<T = any> = (ctx: T, ...extraArgs: any[]) => boolean | Promise<boolean>;
/** A type alias for a validator callback function */
export declare type TValidatorCallback<T = any> = (ctx: T, ...extraArgs: any[]) => void;
/** A type alias for a parser function */
export declare type TParser<T = any, R = any> = (ctx: T, ...extraArgs: any[]) => R | Promise<R>;
/** A type alias for class When and its derived classes */
export declare type TWhenClass<T extends When> = Function & {
    new ({ validate, parse, validCallback, invalidCallback }: {
        validate?: TValidator[];
        parse?: TParser[];
        validCallback?: TValidatorCallback[];
        invalidCallback?: TValidatorCallback[];
    }): T;
};