import { FormGroup, ValidatorFn, AbstractControl, FormArray } from '@angular/forms';
import { InvalidValidationResult } from './invalid-validation-result';
export declare class FormValidators {
    /**
    * Requried when the predicate evaluates to true
    */
    static requiredWhen(pred: (control: AbstractControl) => boolean): ValidatorFn;
    static arrayAtLeastOneHasToBeRequired(): (array: FormArray) => InvalidValidationResult;
    /**
    * Applies the required validator on each child control
    */
    static requiredGroup(group: FormGroup): InvalidValidationResult;
    static range(min?: number, max?: number): ValidatorFn;
    static minValue(min: number): ValidatorFn;
    static maxValue(max: number): ValidatorFn;
    static creditCard(control: AbstractControl): InvalidValidationResult;
    static email(control: AbstractControl): InvalidValidationResult;
    static url(control: AbstractControl): InvalidValidationResult;
    static number(control: AbstractControl): InvalidValidationResult;
    static alpha(control: AbstractControl): InvalidValidationResult;
    static firstCap(control: AbstractControl): InvalidValidationResult;
    /**
    * Depricatedm as validator is being merged with Core: https://github.com/angular/angular/pull/14052
    */
    static compareFields(field1Name: string, field2Name: string): (group: FormGroup) => InvalidValidationResult;
    /**
    * Depricatedm as validator is being merged with Core: https://github.com/angular/angular/pull/14052
    */
    static comparison(...fields: string[]): (group: FormGroup) => InvalidValidationResult;
    static required(control: AbstractControl): InvalidValidationResult;
    static requiredTrue(control: AbstractControl): InvalidValidationResult;
    static minLength(minLength: number): ValidatorFn;
    static maxLength(maxLength: number): ValidatorFn;
    static nullValidator(control: AbstractControl): InvalidValidationResult;
    static compose(validators: ValidatorFn[]): ValidatorFn;
    static composeAsync(validators: ValidatorFn[]): ValidatorFn;
}