import { Enumerable } from "../enumerable";
import { OrderedEnumerable } from "../ordered-enumerable";
import { IComparer } from "../comparer";
declare module '../enumerable' {
    interface Enumerable<TSource> {
        orderBy<TKey>(keySelector: (item: TSource) => TKey, comparer?: IComparer<TKey>): OrderedEnumerable<TSource>;
        orderByDescending<TKey>(keySelector: (item: TSource) => TKey, comparer?: IComparer<TKey>): OrderedEnumerable<TSource>;
    }
}
export declare function orderBy<TSource, TKey>(this: Enumerable<TSource>, keySelector: (item: TSource) => TKey, comparer?: IComparer<TKey>): OrderedEnumerable<TSource>;
export declare function orderByDescending<TSource, TKey>(this: Enumerable<TSource>, keySelector: (item: TSource) => TKey, comparer?: IComparer<TKey>): OrderedEnumerable<TSource>;