The document discusses the map and flatMap functions in Swift and how they relate to functional programming concepts like Functors and Monads. It provides examples of using map and flatMap with Array and Optional types, noting that Array and Optional conform to both the Functor and Monad protocols. References for further reading on Functors, Applicatives, and Monads are also included.

1. Swift
map & flatMap
Sai Li @ Swift Taipei
Yowoo Tech.
2017 / 8 / 8
taipingeric@gmail.com

2. ƒ(x) = x + 1

3. Sequence: map & flatMap

4. Sequence: map

5. Sequence.flatMap()

6. Sequence.flatMap()

7. Sequence.flatMap() -2

8. Optional

9. Optional.map()

10. Difference?

11. Read the Fucking Source Code! :-)
Linus Trovalds

17. Array
map
flatMap * 2
Optional
map
flatMap

18. Array
Optional
map
Array
Optional
flatMap

19. Array
Optional
map Functor
Array
Optional
flatMap Monad
photo

20. Functor

24. Functor
Optional and Array are Functors

25. Monad

26. Monad
Optional and Array are Monad

27. Array
Optional
map Functor
Array
Optional
flatMap Monad

28. References
• http://www.infoq.com/cn/articles/swift-brain-gym-map-and-flatmap
• http://www.mokacoding.com/blog/functor-applicative-monads-in-
pictures/
• https://www.walldevil.com/wallpapers/a28/funny-wallpaper-
wallpapers.jpg
• http://jiyinyiyong.github.io/monads-in-pictures/
• static5.businessinsider.com/image/4d6c271ccadcbb3b132c0000/
linus-torvalds-loves-his-macbook-air.jpg