import { AbstractControl, ValidationErrors, ValidatorFn } from '@angular/forms';
/**
 * @description
 * Provides a set of built-in validators that can be used by form controls.
 *
 * A validator is a function that processes a `FormControl` or collection of
 * controls and returns an error map or null. A null map means that validation has passed.
 *
 * @see [Form Validation](/guide/form-validation)
 *
 * @publicApi
 */
export declare class HtmlValidators {
    /**
     * @description
     * Validator that requires the control have a non-empty value.
     *
     * @usageNotes
     *
     * ### Validate that the field is non-empty
     *
     * ```typescript
     * const control = new FormControl('', Validators.required);
     *
     * console.log(control.errors); // {required: true}
     * ```
     *
     * @returns An error map with the `required` property
     * if the validation check fails, otherwise `null`.
     *
     */
    static required(control: AbstractControl): ValidationErrors | null;
    /**
     * @description
     * Validator that requires the length of the control's value to be greater than or equal
     * to the provided minimum length. This validator is also provided by default if you use the
     * the HTML5 `minlength` attribute.
     *
     * @usageNotes
     *
     * ### Validate that the field has a minimum of 3 characters
     *
     * ```typescript
     * const control = new FormControl('ng', Validators.minLength(3));
     *
     * console.log(control.errors); // {minlength: {requiredLength: 3, actualLength: 2}}
     * ```
     *
     * ```html
     * <input minlength="5">
     * ```
     *
     * @returns A validator function that returns an error map with the
     * `minlength` if the validation check fails, otherwise `null`.
     */
    static minLength(minLength: number): ValidatorFn;
    /**
     * @description
     * Validator that requires the length of the control's value to be less than or equal
     * to the provided maximum length. This validator is also provided by default if you use the
     * the HTML5 `maxlength` attribute.
     *
     * @usageNotes
     *
     * ### Validate that the field has maximum of 5 characters
     *
     * ```typescript
     * const control = new FormControl('Angular', Validators.maxLength(5));
     *
     * console.log(control.errors); // {maxlength: {requiredLength: 5, actualLength: 7}}
     * ```
     *
     * ```html
     * <input maxlength="5">
     * ```
     *
     * @returns A validator function that returns an error map with the
     * `maxlength` property if the validation check fails, otherwise `null`.
     */
    static maxLength(maxLength: number): ValidatorFn;
}