import { ConstraintFunction, Request } from '../interfaces/interfaces';
export declare const traverseAncerstors: (request: Request | null, constraint: ConstraintFunction) => boolean;
/**
 * This helpers use currying to help you to generate constraints
 *
 * @param key
 */
export declare const taggedConstraint: (key: string | number | symbol) => (value: any) => ConstraintFunction;
export declare const namedConstraint: (value: any) => ConstraintFunction;
export declare const typeConstraint: (type: Function | string) => (request?: Request | null | undefined) => boolean;