/**
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file at https://github.com/NG-ZORRO/ng-zorro-antd/blob/master/LICENSE
 */
import { FormControl, FormGroup, ValidatorFn } from '@angular/forms';
import { NzSafeAny } from 'ng-zorro-antd/core/types';
export declare class NsMultipleInputValidators {
    static preventDuplicateKey(formControl: FormGroup): NzSafeAny;
    static allRequired(formControl: FormControl): NzSafeAny;
    static singleRequired(formControl: FormControl): NzSafeAny;
    static minLength(minLength: number): ValidatorFn;
    /**
     * @dynamic
     */
    static maxLength(maxLength: number): ValidatorFn;
}