import { IterableX } from './iterablex';
export declare class DistinctUntilChangedIterable<TSource, TKey> extends IterableX<TSource> {
    private _source;
    private _keySelector;
    private _comparer;
    constructor(source: Iterable<TSource>, keySelector: (value: TSource) => TKey, comparer: (first: TKey, second: TKey) => boolean);
    [Symbol.iterator](): IterableIterator<TSource>;
}
/**
 * Returns consecutive distinct elements based on a key value by using the specified equality comparer to compare key values.
 * @param {Iterable<TSource>} source Source sequence.
 * @param {function(value: TSource): TKey} [keySelector] Key selector.
 * @param {function(x: TKey, y: TKey): boolean} [comparer] Comparer used to compare key values.
 * @return {Iterable<TSource>} Sequence without adjacent non-distinct elements.
 */
export declare function distinctUntilChanged<TSource, TKey>(source: Iterable<TSource>, keySelector?: (value: TSource) => TKey, comparer?: (first: TKey, second: TKey) => boolean): IterableX<TSource>;