This document discusses functional reactive programming and related concepts like immutable data, pure functions, and side effect-free programming. It introduces reactive programming as an asynchronous programming paradigm focused on data streams and propagating change. RxSwift is mentioned as a Swift library that implements reactive programming ideas by returning Observables for asynchronous operations and allowing streams to be connected and processed with operators.

1. 송치원 (곰튀김)
iamchiwon.github.io
Functional Reactive
Programming Paradigm

2. Immutable
Side Effect
Pure Function
Composition
Iterator
Generator
Function
Reduce
Map
Consumer
First-Class Citizen
High-Order Function
Imperative Programming
Declarative Programming
Reactive
RxSwift
Stream
Asynchronous
Terms
Functional Programming
Event Stream
Data Stream
Filter

3. Functional
Reactive
Programming
Paradigm
Contents

4. Functional
Reactive
Programming
Paradigm
Contents

5. Programming
Program
input output

6. Paradigm
https://ko.wikipedia.org/wiki/패러다임

7. Paradigm
Low memory
Optimized
Medium Memory High memory
Concurrency
Performance / Responsibility
Data : Program = 1:1
Reusable
Abstract Data
Low Memory Mass Production Concurrency

8. Functional
Data
Program Program Program Program

9. Functional
Data
Program Program Program Program
Immutable

10. Functional
Side-Effect
Pure function

11. Functional
❶
❸
❷

12. Functional
❶
❸
❷
Composition
Generator
Function
Consumer

13. Functional
First Class CitizenHigh-Order function

14. Functional
OOP 김밥만들기

15. Functional
FP 김밥만들기

16. Functional
Imperative programming
명령형 프로그래밍
Declarative programming
선언형 프로그래밍
commands
functions

17. Functional
•데이터는 immutable 하게 취급하자
•데이터 변경이 필요할 때는 새로 만들자
•Side-Effect 을 없애기 위해서 Pure Function 을 사용하자
•Function 들의 Composition과 High-Order Function
으로 프로그램을 만들자
•Data가 아닌 Process에 집중해서 프로그램을 만들자

18. Functional
ISSUE
Expensive job
Async job
Wait
?
Callback
Delegate

19. Reactive
https://en.wikipedia.org/wiki/Reactive_programming
In computing, reactive programming is an asynchronous
programming paradigm concerned with data streams
and the propagation of change.

20. Reactive
Reactive Libraries
Reactive Extension
Java, JS, .NET, Scala, Swift, Python,
…
http://reactivex.io/
ReactiveCocoa Objective-C https://github.com/ReactiveCocoa/ReactiveCocoa
ReactiveSwift Swift https://github.com/ReactiveCocoa/ReactiveSwift
Sodium Java, JS, Swift, Kotlin, C, Rust https://github.com/SodiumFRP
ReactFX Java https://github.com/TomasMikula/ReactFX
Reactive-Banana Haskell http://wiki.haskell.org/Reactive-banana
Bacon.JS JS https://baconjs.github.io/
Kefir.JS JS https://rpominov.github.io/kefir/
Flapjax JS http://www.flapjax-lang.org/

21. Reactive
Generator
Consumer
map
Filter
Reduce
Stream
Observable
Subscriber
Operator

22. Reactive
getText
Subscribe
Text
1
2
3
url

23. Reactive

24. Reactive

25. Reactive

26. pod ‘RxSwift’
import RxSwift
Reactive

27. Reactive pod ‘RxSwift’
import RxSwift

28. Reactive pod ‘RxCocoa’
import RxCocoa

29. Reactive
•Async 한 처리를 Functional 하게 처리하자
•리턴값은 Stream인 Observable을 반환하자
•Stream 에 흐르는 Data/Event 를 Operator 로 처리하자
•Stream과 Stream을 연결하자
•Data가 아닌 Process에 집중해서 프로그램을 만들자

30. Functional
Side-Effect 가 없도록 프로그래밍 하는 패러다임
Reactive
Async 한 작업을 Functional 하게 처리하는 아이디어
RxSwift
Reactive 아이디어를 구현한 Swift 라이브러리
Summary