--- /dev/null
+import { Observable } from '../Observable';
+import { OperatorFunction } from '../types';
+/**
+ * Branch out the source Observable values as a nested Observable with each
+ * nested Observable emitting at most `windowSize` values.
+ *
+ * <span class="informal">It's like {@link bufferCount}, but emits a nested
+ * Observable instead of an array.</span>
+ *
+ * ![](windowCount.png)
+ *
+ * Returns an Observable that emits windows of items it collects from the source
+ * Observable. The output Observable emits windows every `startWindowEvery`
+ * items, each containing no more than `windowSize` items. When the source
+ * Observable completes or encounters an error, the output Observable emits
+ * the current window and propagates the notification from the source
+ * Observable. If `startWindowEvery` is not provided, then new windows are
+ * started immediately at the start of the source and when each window completes
+ * with size `windowSize`.
+ *
+ * ## Examples
+ * Ignore every 3rd click event, starting from the first one
+ * ```ts
+ * import { fromEvent } from 'rxjs';
+ * import { windowCount, map, mergeAll, skip } from 'rxjs/operators';
+ *
+ * const clicks = fromEvent(document, 'click');
+ * const result = clicks.pipe(
+ * windowCount(3),
+ * map(win => win.pipe(skip(1))), // skip first of every 3 clicks
+ * mergeAll() // flatten the Observable-of-Observables
+ * );
+ * result.subscribe(x => console.log(x));
+ * ```
+ *
+ * Ignore every 3rd click event, starting from the third one
+ * ```ts
+ * import { fromEvent } from 'rxjs';
+ * import { windowCount, mergeAll } from 'rxjs/operators';
+ *
+ * const clicks = fromEvent(document, 'click');
+ * const result = clicks.pipe(
+ * windowCount(2, 3),
+ * mergeAll(), // flatten the Observable-of-Observables
+ * );
+ * result.subscribe(x => console.log(x));
+ * ```
+ *
+ * @see {@link window}
+ * @see {@link windowTime}
+ * @see {@link windowToggle}
+ * @see {@link windowWhen}
+ * @see {@link bufferCount}
+ *
+ * @param {number} windowSize The maximum number of values emitted by each
+ * window.
+ * @param {number} [startWindowEvery] Interval at which to start a new window.
+ * For example if `startWindowEvery` is `2`, then a new window will be started
+ * on every other value from the source. A new window is started at the
+ * beginning of the source by default.
+ * @return {Observable<Observable<T>>} An Observable of windows, which in turn
+ * are Observable of values.
+ * @method windowCount
+ * @owner Observable
+ */
+export declare function windowCount<T>(windowSize: number, startWindowEvery?: number): OperatorFunction<T, Observable<T>>;