import { AbstractControl, ValidationErrors, Validator } from '@angular/forms';
import { NullableDaterange } from '../interfaces/daterange.interface';
import * as i0 from "@angular/core";
/**
 * Validator for daterangepicker to validate that 'from' *AND* 'to' date are not `null`.
 * Will throw `required` validation error.
 *
 * Validator is applied to the ClrDaterangepickerDirective with `required` attribute.
 * Or when set manually with `clrDaterangeRequired` attribute.
 *
 * Validator is active by default when applied. It can be disabled with: `[clrDaterangeRequired]="false"`
 */
export declare class ClrDaterangeRequiredValidator implements Validator {
    /** Validation error name. */
    static readonly validationErrorName = "required";
    private _active;
    /**
     * Disable validator by setting value to `false`.
     */
    set active(active: boolean | string | undefined | null);
    /**
     * Validator method. Method that performs synchronous validation against the provided control.
     * @param control - The control to validate against.
     * @returns A map of validation errors if validation fails, otherwise null.
     */
    validate(control: AbstractControl<NullableDaterange, any>): ValidationErrors | null;
    static ɵfac: i0.ɵɵFactoryDeclaration<ClrDaterangeRequiredValidator, never>;
    static ɵdir: i0.ɵɵDirectiveDeclaration<ClrDaterangeRequiredValidator, "[clrDaterangepicker][required], [clrDaterangeRequired]", never, { "active": { "alias": "clrDaterangeRequired"; "required": false; }; }, {}, never, never, false, never>;
}