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@reactivex/rxjs

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Reactive Extensions for modern JavaScript

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import { Observable } from '../Observable'; /** * Returns an Observable that emits all items emitted by the source Observable that are distinct by comparison from previous items, * using a property accessed by using the key provided to check if the two items are distinct. * If a comparator function is provided, then it will be called for each item to test for whether or not that value should be emitted. * If a comparator function is not provided, an equality check is used by default. * As the internal HashSet of this operator grows larger and larger, care should be taken in the domain of inputs this operator may see. * An optional parameter is also provided such that an Observable can be provided to queue the internal HashSet to flush the values it holds. * @param {string} key string key for object property lookup on each item. * @param {function} [compare] optional comparison function called to test if an item is distinct from previous items in the source. * @param {Observable} [flushes] optional Observable for flushing the internal HashSet of the operator. * @return {Observable} an Observable that emits items from the source Observable with distinct values. * @method distinctKey * @owner Observable */ export declare function distinctKey<T>(key: string, compare?: (x: T, y: T) => boolean, flushes?: Observable<any>): Observable<T>; export interface DistinctKeySignature<T> { (key: string): Observable<T>; <K>(key: string, compare: (x: K, y: K) => boolean, flushes?: Observable<any>): Observable<T>; }