This document contains slides from a presentation on ReactiveCocoa operators given by Hai Feng Kao. It defines and provides examples of hot and cold signals, as well as common ReactiveCocoa operators like map, filter, take, skip, distinctUntilChanged, merge, then, combineLatest, zip, replay, and replayLast. The last section thanks attendees for the presentation.

1. ReactiveCocoa
Operators
Hai Feng Kao
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2. Quiz 1
What does MVVM stand for?
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3. Quiz2
What are the advantages of MVVM?
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4. Quiz 3
What is the speaker’s name?
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5. ReactiveCocoa
Operators
Hai Feng Kao
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6. Hot n Cold
• Hot Signal
• sends values regardless of
whether it has any
subscribers
• but only send values after
their their subscription time.
• Cold Signal
• defers its work and the
sending of any values until it
has a subscriber 6

7. Cold Signal Example
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8. Hot Signal Example
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9. map
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10. filter
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11. take
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12. skip
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13. skip
• RACObserve sends the current value
immediately
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14. distinctUntilChanged
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15. merge
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16. then
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17. RACSubject
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18. combineLatest:reduce:
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19. zip:reduce:
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20. Hot n Cold
• Hot Signal
• sends values regardless of
whether it has any subscribers
• but only send values after their
their subscription time.
• Cold Signal
• defers its work and the sending
of any values until it has a
subscriber
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21. Cold Signal Example
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22. replay
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23. replayLast
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24. replayLazily
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25. replay (another example)
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26. replayLazily (another example)
same as replay
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27. replayLast (another example)
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28. Next Class
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29. Q&A
Thank you
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