import { SchemaFnOptions } from '@ioc:Adonis/Core/Env';
/**
 * Enforces value to be one of the defined choices
 */
export declare function oneOf(choices: any[], options?: SchemaFnOptions): (key: string, value?: string | undefined) => any;
export declare namespace oneOf {
    var optional: (choices: any[], options?: SchemaFnOptions | undefined) => (key: string, value?: string | undefined) => any;
}