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- /** @prettier */
- import { MonoTypeOperatorFunction, SchedulerLike } from '../types';
- /**
- * Re-emits all notifications from source Observable with specified scheduler.
- *
- * <span class="informal">Ensure a specific scheduler is used, from outside of an Observable.</span>
- *
- * `observeOn` is an operator that accepts a scheduler as a first parameter, which will be used to reschedule
- * notifications emitted by the source Observable. It might be useful, if you do not have control over
- * internal scheduler of a given Observable, but want to control when its values are emitted nevertheless.
- *
- * Returned Observable emits the same notifications (nexted values, complete and error events) as the source Observable,
- * but rescheduled with provided scheduler. Note that this doesn't mean that source Observables internal
- * scheduler will be replaced in any way. Original scheduler still will be used, but when the source Observable emits
- * notification, it will be immediately scheduled again - this time with scheduler passed to `observeOn`.
- * An anti-pattern would be calling `observeOn` on Observable that emits lots of values synchronously, to split
- * that emissions into asynchronous chunks. For this to happen, scheduler would have to be passed into the source
- * Observable directly (usually into the operator that creates it). `observeOn` simply delays notifications a
- * little bit more, to ensure that they are emitted at expected moments.
- *
- * As a matter of fact, `observeOn` accepts second parameter, which specifies in milliseconds with what delay notifications
- * will be emitted. The main difference between {@link delay} operator and `observeOn` is that `observeOn`
- * will delay all notifications - including error notifications - while `delay` will pass through error
- * from source Observable immediately when it is emitted. In general it is highly recommended to use `delay` operator
- * for any kind of delaying of values in the stream, while using `observeOn` to specify which scheduler should be used
- * for notification emissions in general.
- *
- * ## Example
- *
- * Ensure values in subscribe are called just before browser repaint
- *
- * ```ts
- * import { interval, observeOn, animationFrameScheduler } from 'rxjs';
- *
- * const someDiv = document.createElement('div');
- * someDiv.style.cssText = 'width: 200px;background: #09c';
- * document.body.appendChild(someDiv);
- * const intervals = interval(10); // Intervals are scheduled
- * // with async scheduler by default...
- * intervals.pipe(
- * observeOn(animationFrameScheduler) // ...but we will observe on animationFrame
- * ) // scheduler to ensure smooth animation.
- * .subscribe(val => {
- * someDiv.style.height = val + 'px';
- * });
- * ```
- *
- * @see {@link delay}
- *
- * @param scheduler Scheduler that will be used to reschedule notifications from source Observable.
- * @param delay Number of milliseconds that states with what delay every notification should be rescheduled.
- * @return A function that returns an Observable that emits the same
- * notifications as the source Observable, but with provided scheduler.
- */
- export declare function observeOn<T>(scheduler: SchedulerLike, delay?: number): MonoTypeOperatorFunction<T>;
- //# sourceMappingURL=observeOn.d.ts.map
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