import { UntypedFormControl, FormGroupDirective, NgForm } from '@angular/forms';
import { ErrorStateMatcher } from '@angular/material/core';
/** Error when invalid control is dirty or touched. */
export declare class FormErrorStateMatcher implements ErrorStateMatcher {
    isErrorState: (control: (UntypedFormControl | null), form: (FormGroupDirective | NgForm | null)) => boolean;
}