import { OnDestroy } from '@angular/core';
import { Validator, AbstractControl } from '@angular/forms';
import * as i0 from "@angular/core";
export declare class ValidateEqualDirective implements Validator, OnDestroy {
    otherControl: string;
    private valueChangesSub;
    constructor(otherControl: string);
    ngOnDestroy(): void;
    validate(selfControl: AbstractControl): any;
    private isEqual;
    private unifyEmptyStrings;
    private isDefined;
    static ɵfac: i0.ɵɵFactoryDeclaration<ValidateEqualDirective, [{ attribute: "ngValidateEqual"; }]>;
    static ɵdir: i0.ɵɵDirectiveDeclaration<ValidateEqualDirective, "[ngValidateEqual]", never, {}, {}, never>;
}