import { DateTime } from 'luxon';
import { AbstractControl, ValidationErrors, ValidatorFn } from '@angular/forms';
export declare class CustomValidators {
    /**
     * Validates that a given DateTime value does not exceed a maximum allowed DateTime.
     *
     * @param max The maximum allowed DateTime.
     * @returns A validator function that checks if the value exceeds the max DateTime.
     */
    static maxDateTime(max: DateTime): ValidatorFn;
    /**
     * Validates that a given DateTime value is not earlier than a minimum allowed DateTime.
     *
     * @param min The minimum allowed DateTime.
     * @returns A validator function that checks if the value is below the min DateTime.
     */
    static minDateTime(min: DateTime): ValidatorFn;
    /**
     * Validates that a given value is **not** a string.
     *
     * @param control The form control being validated.
     * @returns A validation error if the value is a string, otherwise null.
     */
    static nonString(control: AbstractControl): ValidationErrors | null;
    /**
     * Validates that a given value is a number.
     *
     * @returns A validator function that checks if the value is a number.
     */
    static isNumber(): ValidatorFn;
    /**
     * Validates that a given value is a whole number (integer).
     *
     * @returns A validator function that checks if the value is a whole number.
     */
    static wholeNumber(): ValidatorFn;
}