import { PipeTransform } from '@angular/core';
import * as i0 from "@angular/core";
export declare class GroupByPipe implements PipeTransform {
    transform(input: any, discriminator?: any, delimiter?: string): any;
    private groupBy;
    private extractKeyByDiscriminator;
    static ɵfac: i0.ɵɵFactoryDeclaration<GroupByPipe, never>;
    static ɵpipe: i0.ɵɵPipeDeclaration<GroupByPipe, "groupBy", false>;
}