import { Runtype } from './runtype';
/**
 * A string.
 *
 * Options:
 *
 *   minLength .. reject strings that are shorter than that
 *   maxLength .. reject strings that are longer than that
 *   trim .. when true, remove leading and trailing spaces from the string
 *   match .. reject strings that do not match against provided RegExp
 */
export declare function string(options?: {
    minLength?: number;
    maxLength?: number;
    trim?: boolean;
    match?: RegExp;
}): Runtype<string>;