import DataOperation from './base.js';
import type { SortExpression, SortState } from './sort/types.js';
export default class SortDataOperation<T> extends DataOperation<T> {
    protected orderBy: Map<string, number>;
    protected compareValues<U>(first: U, second: U): number;
    protected compareObjects(first: T, second: T, expression: SortExpression<T>): number;
    apply(data: T[], state: SortState<T>): T[];
}