import type { SyncReactNode } from '../types';
interface IsUrlOptions {
    protocols?: string[];
    allowLocalhost?: boolean;
}
export declare function isUrl(error?: SyncReactNode): (value: unknown) => SyncReactNode;
export declare function isUrl(options: IsUrlOptions, error?: SyncReactNode): (value: unknown) => SyncReactNode;
export {};
