import { AbstractControl, Validator } from '@angular/forms';
import * as i0 from "@angular/core";
export declare class CheckboxRequiredValidator implements Validator {
    required: boolean | string;
    constructor();
    validate(control: AbstractControl): {
        [key: string]: any;
    } | null;
    static ɵfac: i0.ɵɵFactoryDeclaration<CheckboxRequiredValidator, never>;
    static ɵdir: i0.ɵɵDirectiveDeclaration<CheckboxRequiredValidator, "ui-checkbox[required]", never, { "required": "required"; }, {}, never, never, false>;
}
