import { AnySchema } from './AnySchema';
export declare class StringSchema<TReq = true, TNull = false> extends AnySchema<TReq, TNull> {
    readonly schema = "string";
    constructor();
    min(min: number): this;
    max(max: number): this;
    trim(): this;
    regex(reg: RegExp): this;
    email(): this;
    optional(): StringSchema<false, TNull>;
    nullable(): StringSchema<TReq, true>;
}