1.x: added distinctUntilChanged(comparator) #4001
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| */ | ||
| public final Observable<T> distinctUntilChanged(Func2<? super T, ? super T, Boolean> comparator) { | ||
| return lift(new OperatorDistinctUntilChanged<>(new Func1<T, Object>() { | ||
| T previousValue; |
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This will be shared among all subscribers of the chain and you won't get proper results when multiple subscribers run the chain concurrently.
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Please add unit tests that verify the behavior. |
| * @see <a href="http://reactivex.io/documentation/operators/distinct.html">ReactiveX operators documentation: Distinct</a> | ||
| */ | ||
| public final Observable<T> distinctUntilChanged(Func2<? super T, ? super T, Boolean> comparator) { | ||
| return lift(new OperatorDistinctUntilChanged<>(new Func1<T, Object>() { |
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Our target is Java 6 where the diamond operator is not allowed.
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How about this one? |
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Sorry for the delay. I remembered there was a discussion about this overload a while ago in #395. The verdict was to not have them and you have to create your own wrapper class with custom The decision may be revised, depending on the other's opinions. (Otherwise, I would have done it differently, not with that subscriberProvider). |
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See #4034 about how I'd implement this instead (easier shown in code than as a comment). Let me know if you want to adjust your PR. |
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If you think that my PR doesn't cover everything you wanted then yes. Otherwise, I leave it to you. |
No, I think your PR is just okay and do what I wanted and do it better than mine own 👍 |
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Yes, you can close this. Thanks for your contribution anyway! If you have any further improvement suggestions / PRs for the library don't hesitate to post them. (If you need some hints about operator coding styles and structure, try looking at the common and simpler operators implementations.) |
For some cases,
Observable.distinctUntilChanged(keySelector)isn't enough. For example, when data consists of 2+ objects with ID, you cannot simply summarize them and use it as a key. Also often there are stream of arrays of data which can't be distincted easily and generically.So I think
Observable.distinctUntilChanged(comparator)would be helpful. I use kinda tricky implementation, but think, it is okey. Firstly I tried to add ctor to OperatorDistinctUntilChanged(), but it was... too bad.p.s. I was really confused by
and spent some time trying to create some sort of temporal branch here (newbie me). But finally looked up into PRs and so that it is okey to PR into 1.x. Is it an error in .md-file?