Merge branch 'master' into lettable-start

Author: benlesh

CHANGELOG.md

@@ -1,3 +1,14 @@
+<a name="5.4.3"></a>
+## [5.4.3](https://github.com/ReactiveX/RxJS/compare/5.4.2...v5.4.3) (2017-08-10)
+
+
+### Bug Fixes
+
+* **compilation:** compiles under typescript 2.4.2 ([#2780](https://github.com/ReactiveX/RxJS/issues/2780)) ([d2a32f9](https://github.com/ReactiveX/RxJS/commit/d2a32f9))
+* **exports:** add exports for missing static operators: generate, ([08c4196](https://github.com/ReactiveX/RxJS/commit/08c4196))
+
+
+
 <a name="5.4.2"></a>
 ## [5.4.2](https://github.com/ReactiveX/RxJS/compare/5.4.1...v5.4.2) (2017-07-05)
 

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@reactivex/rxjs",
-  "version": "5.4.2",
+  "version": "5.4.3",
   "description": "Reactive Extensions for modern JavaScript",
   "main": "index.js",
   "config": {

src/operator/timeoutWith.ts

@@ -15,10 +15,49 @@ export function timeoutWith<T, R>(this: Observable<T>, due: number | Date, withO
 /* tslint:enable:max-line-length */
 
 /**
- * @param due
- * @param withObservable
- * @param scheduler
- * @return {Observable<R>|WebSocketSubject<T>|Observable<T>}
+ *
+ * Errors if Observable does not emit a value in given time span, in case of which
+ * subscribes to the second Observable.
+ *
+ * <span class="informal">It's a version of `timeout` operator that let's you specify fallback Observable.</span>
+ *
+ * <img src="./img/timeoutWith.png" width="100%">
+ *
+ * `timeoutWith` is a variation of `timeout` operator. It behaves exactly the same,
+ * still accepting as a first argument either a number or a Date, which control - respectively -
+ * when values of source Observable should be emitted or when it should complete.
+ *
+ * The only difference is that it accepts a second, required parameter. This parameter
+ * should be an Observable which will be subscribed when source Observable fails any timeout check.
+ * So whenever regular `timeout` would emit an error, `timeoutWith` will instead start re-emitting
+ * values from second Observable. Note that this fallback Observable is not checked for timeouts
+ * itself, so it can emit values and complete at arbitrary points in time. From the moment of a second
+ * subscription, Observable returned from `timeoutWith` simply mirrors fallback stream. When that
+ * stream completes, it completes as well.
+ *
+ * Scheduler, which in case of `timeout` is provided as as second argument, can be still provided
+ * here - as a third, optional parameter. It still is used to schedule timeout checks and -
+ * as a consequence - when second Observable will be subscribed, since subscription happens
+ * immediately after failing check.
+ *
+ * @example <caption>Add fallback observable</caption>
+ * const seconds = Rx.Observable.interval(1000);
+ * const minutes = Rx.Observable.interval(60 * 1000);
+ *
+ * seconds.timeoutWith(900, minutes)
+ *     .subscribe(
+ *         value => console.log(value), // After 900ms, will start emitting `minutes`,
+ *                                      // since first value of `seconds` will not arrive fast enough.
+ *         err => console.log(err) // Would be called after 900ms in case of `timeout`,
+ *                                 // but here will never be called.
+ *     );
+ *
+ * @param {number|Date} due Number specifying period within which Observable must emit values
+ *                          or Date specifying before when Observable should complete
+ * @param {Observable<T>} withObservable Observable which will be subscribed if source fails timeout check.
+ * @param {Scheduler} [scheduler] Scheduler controlling when timeout checks occur.
+ * @return {Observable<T>} Observable that mirrors behaviour of source or, when timeout check fails, of an Observable
+ *                          passed as a second parameter.
  * @method timeoutWith
  * @owner Observable
  */