import { Identifier } from "treedoc";
export declare class OrderBy<V> {
    id: Identifier<V, any>;
    desc: boolean;
    constructor(id?: Identifier<V, any>, desc?: boolean);
}
export declare class Summary {
    identifier: Identifier<any, any>;
    constructor(identifier: Identifier<any, any>);
    total: number;
    average: number;
    max: any;
    min: any;
    update(e: any): void;
}
export declare class GroupSummary {
    groupId?: string | undefined;
    summaries: Array<Summary> | undefined;
    constructor(groupId?: string | undefined, summaries?: Array<Summary> | undefined);
    count: number;
}
export default class ListUtils {
    static orderBy<V>(source: V[], orderBys: OrderBy<V>[]): V[];
    static summary<V>(source: V[], ids: Array<Identifier<V, any>>): Array<Summary>;
    static computeIfAbsent<K, V>(map: Map<K, V>, key: K, valFun: (k: K) => V): V;
    static groupBy<V>(source: V[], ids: Array<Identifier<V, any>>): Map<string, V[]>;
    static summaryGroupBy<V>(source: V[], groupBy: Array<Identifier<V, any>>, summaryFor: Array<Identifier<V, any>>): Array<GroupSummary>;
    static sum<V>(source: V[], id: Identifier<V, number>): number;
}