Completable operator review

[stealthcode]

Before we release rx.Completable into the wild (that is before we release v1.1.1) I'd like to open up a thread for discussion regarding Completable's instance methods, static methods, as well as any conversion methods to/from Observable and Single. Please feel free to review and comment here with any concerns. Any that need to be addressed should result in either a PR or another issue to track or discuss.

[stealthcode]

Note that there is already a discussion in #3570 regarding the instance method Observable<T> endsWith(Observable<T>) and the proposed rename to andThen.

[stealthcode]

If we rename endWith then I suggest we rename the Completable startWith(Observable<T>) method to an overload of concatWith(Observable<T>) and deleting Completable startWith(Completable).

[stealthcode]

Also the get() method (and overload) are very similar to the functionality of Observable.toBlocking() except that it returns the error if any exists. This differs from Observable and Single toBlocking in that a BlockingObservable will throw any exception emitted to the subscriber's onError. Should we make Completable's get method consistent in behavior with a BlockingObservable? If so then a rename may also be in order. Thoughts?

[akarnokd]

rename the Completable startWith(Observable) method to an overload of concatWith(Observable)

The problem with this rename is that startWith indicates the Observable runs first whereas concatWith indicates the Observable runs last which doesn't preserve the intention.

deleting Completable startWith(Completable)

Okay.

Also the get() method (and overload) are very similar to the functionality of Observable.toBlocking() except that it returns the error if any exists.

I've omitted BlockingCompletable because there are only 2 x 2 reasonable blocking operations: await and get() +1 timed overload each. But we can remove get for the sake of clarity.

[akarnokd]

Any more on this or can it be closed?