import { ValidatorFn } from '@angular/forms';
/**
 * validator which checks to make sure that the sum of all file sizes
 * does not exceed the maximum specified size
 * designed to work with a FormControl attached to a FileInputComponent
 * @param maxFilesTotalSizeBytes the maximum valid sum of all file sizes, in bytes
 */
export declare function filesTotalSizeValidator(maxFilesTotalSizeBytes: number): ValidatorFn;