Functional Kotlin makes Kotlin functional

KotlinConf 2023 Global in Songdo에서 발표한 코틀린 함수형 프로그래밍 발표 자료입니다.

Transcript

1. @l2hyunwoo
   
   
   KotlinConf’23 Global in Songdo
   
   
   Mathpresso Inc. Android/React Native Developer
   Functional Kotlin
   
   
   Makes
   
   
   Kotlin functional
   
   
   HyunWoo Lee
   

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2. ೣࣻഋ ೐۽Ӓې߁җ য়೧
   Lambda Algebra Monoid
   Functor / Applicative Functor Tail recursion
   Currying
   

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3. ೣࣻഋ ೐۽Ӓې߁җ য়೧
   Lambda Algebra Monoid
   Functor / Applicative Functor Tail recursion
   Currying
   ੿݈ ੉ѱ पઁ ѐߊী ੄޷о ੓ਸөਃ?
   

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4. ೣࣻഋ ೐۽Ӓې߁ ੽Ӕ
   ݾ੸ਸ ੉೧ೞҊ
   
   
   যڌѱ ࢎਊ೧ঠೡ ૑ ঌইঠ ೞݴ
   
   
   Ӓ ੉റী ޖ঺੉ ੓ח ૑ ౵ঈ೧ب ן૑ ঋ׮
   

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5. Why we should use it?
   ೣࣻഋ ೐۽Ӓې߁ਸ ഝਊೞݶ
   
   
   ௏٘ܳ рѾೞѱ ੘ࢿೡ ࣻ ੓Ҋ ӝמ੄ ഛ੢੉ ए਋ݴ
   
   
   ࠁ׮ উ੹ೠ ௏٘ܳ ੘ࢿೡ ࣻ ੓׮
   

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6. рѾೠ ௏٘ ੘ࢿೞӝ
   

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7. рѾೠ ௏٘ ੘ࢿೞӝ
   

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8. рѾೠ ௏٘ ੘ࢿೞӝ
   

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9. рѾೠ ௏٘ ੘ࢿೞӝ
   

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10. ߸زਸ ઴੉ݶࢲ উ੿ࢿ ֫੉ӝ
    

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11. ߸زਸ ઴੉ݶࢲ উ੿ࢿ ֫੉ӝ
    

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12. ߸زਸ ઴੉ݶࢲ উ੿ࢿ ֫੉ӝ
    ё୓/৻ࠗ ࢚క੄
    
    
    ߸ز੉ ੓ח ࠗ࠙਷
    
    
    ࠶۾ Scopeਵ۽
    
    
    Ѻܻೠ׮
    

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13. ਫ਼Ӭ! ੉Ѣ ೣࣻഋ ೐۽Ӓې߁੉ ݏաਃ?
    Functional Programming is sometimes treated as synonymous with
    
    
    Purely functional programming.
    
    
    When a pure function is called with some given arguments,
    
    
    it will always return the same result,
    
    
    and cannot be affected by any mutable state or other side effect.
    
    
    -
    Hudak, Paul (Conception, evolution and application of functional programming lauguages)
    

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14. Pure Function and Side Effect
    function sum(x: int, y: int)
    

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15. Pure Function and Side Effect
    function sum(x: int, y: int)
    (
    2, 5
    )
    

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16. Pure Function and Side Effect
    function sum(x: int, y: int)
    (
    2, 5
    )
    7
    

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17. function sum(x: int, y: int)
    (
    2, 5
    )
    7
    ੑ۱੉ زੌೞݶ
    
    
    Ѿҗо ೦࢚ э਷ ೣࣻܳ
    
    
    ࣽࣻ ೣࣻ
    (
    Pure Function)
    
    
    ۄ ೠ׮
    Pure Function and Side Effect
    

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18. Pure Function and Side Effect
    function sumWithSideEffect(x: int, y: int)
    

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19. Pure Function and Side Effect
    function sumWithSideEffect(x: int, y: int)
    (
    2, 5
    )
    1st
    

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20. Pure Function and Side Effect
    function sumWithSideEffect(x: int, y: int)
    (
    2, 5
    )
    7
    1st
    

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21. Pure Function and Side Effect
    function sumWithSideEffect(x: int, y: int)
    (
    3, 6
    )
    2nd
    

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22. Pure Function and Side Effect
    function sumWithSideEffect(x: int, y: int)
    (
    3, 6
    )
    2nd
    16
    

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23. Pure Function and Side Effect
    function sumWithSideEffect(x: int, y: int)
    (
    3, 6
    )
    2nd
    16
    

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24. Pure Function and Side Effect
    

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25. Pure Function and Side Effect
    ೣࣻ ղীࢲ ҙ੢ೞ૑ ঋח,
    
    
    ੹৉ ࢚క/߸ࣻ ഑਷ (౵ੌ, ചݶ) ੑ୹۱١ਸ ನೣೠ
    
    
    ৻ࠗ ࢚కী ৔ೱਸ ઴ ࣻ ੓Ҋ ੉ܳ ҙ଴ೞח ೯ਤܳ ನೣೞח ೣࣻܳ
    
    
    Side Effectۄ ೠ׮.
    

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26. Pure Function and Side Effect
    ೣࣻഋ ೐۽Ӓې߁ਸ ഝਊೞݶ
    
    
    ௏٘ܳ рѾೞѱ ੘ࢿೡ ࣻ ੓Ҋ ӝמ੄ ഛ੢੉ ए਋ݴ
    
    
    ࠁ׮ উ੹ೠ ௏٘ܳ ੘ࢿೡ ࣻ ੓׮
    

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27. Pure Function and Side Effect
    ࣽࣻೣࣻܳ ࢎਊೞݶ زੌೠ Ѿҗܳ ৘ஏೡ ࣻ ੓ਵ޲۽ (ଵઑ ైݺࢿ)
    
    
    ೣࣻ Ӓ ੗୓ܳ ݽٕചػ ӝמਵ۽ ࢎਊೡ ࣻ ੓׮.
    
    
    ژೠ ৻ࠗ о߸ ࢚కܳ ߸҃ೞ૑ ঋਵ޲۽
    
    
    زदࢿ ೐۽Ӓې߁ীࢲ ҕਬ ੗ਗ ߸҃ী ؀ೠ ҙबࢎܳ ઁೡ ࣻ ੓׮.
    
    
    ੉۠ ੉੼ਵ۽ ೣࣻഋ ೐۽Ӓې߁ীࢲח ࣽࣻ ೣࣻ੄ ࢎਊਸ ૑ೱೠ׮.
    

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28. Aspect of Functional Programming
    Ӓ۞ݶ ࣽࣻ ೣࣻ݅ਸ ࢎਊೞח Ѫ੉
    
    
    ೣࣻഋ ೐۽Ӓې߁ ߑधੌө?
    

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29. Aspect of Functional Programming
    Ӓۧӝח ೞա,
    
    
    Ӓېо૑Ҍ рױೠ ӝמ ೞաઑର
    
    
    ઁ؀۽ ٜ݅ ࣻ হ׮
    

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30. Aspect of Functional Programming
    ৻ࠗ ࣁ҅ܳ ߸҃ਸ दெঠ ೞա
    
    
    ߸҃ਸ दఃח ࠗ࠙ਸ ୭ࣗചೞҊ ҳ࠙(Ѻܻ)दః੗
    

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31. ߸زਸ ઴੉ݶࢲ উ੿ࢿ ֫੉ӝ
    ё୓/৻ࠗ ࢚క੄
    
    
    ߸ز੉ ੓ח ࠗ࠙਷
    
    
    ࠶۾ Scopeਵ۽
    
    
    Ѻܻೠ׮
    

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32. Ҋରೣࣻܳ ഝਊೠ ӝמ ഛ੢
    

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33. Ҋରೣࣻܳ ഝਊೠ ӝמ ഛ੢
    CSVо ইצ ׮ܲ ౵ੌ ഋध
    
    
    ഑਷ Plain Text۽ Append
    ೞח ӝמ੉ ୶оػ׮ݶ?
    

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34. Ҋରೣࣻܳ ഝਊೠ ӝמ ഛ੢
    ё୓ܳ Stringਵ۽ ੹ജೞח ۽૒ਸ
    ৻ࠗীࢲ ઱ੑदெ
    
    
    ҕా ۽૒ী ׮ഋࢿਸ ઁҕ
    

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35. ઺р ੼Ѩ
    ਸ ੉೧ೞҊ
    
    
    ࢎਊ೧ঠೡ ૑ ঌইঠ ೞݴ
    
    
    Ӓ ੉റী ޖ঺੉ ੓ח ૑ ౵ঈ೧ب ן૑ ঋ׮
    ݾ੸
    যڌѱ
    

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36. ઺р ੼Ѩ
    → উ੿ࢿ, ਬ૑ࠁࣻࢿ, оةࢿ ૐо
    
    
    → ࣽࣻೣࣻ ഝਊ, Side Effect Ѻܻ
    ݾ੸
    যڌѱ
    

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37. More, Functional Programming
    Ҋରೣࣻܳ ഝਊೞৈ ੤ࢎਊࢿਸ ՑযৢܻҊ
    
    
    ࠁ׮ ؊ উ੿੸ਵ۽ ೐۽Ӓې߁ਸ ೞҊ र׮ݶ?
    

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38. More, Functional Programming
    Ҋରೣࣻܳ ഝਊೞৈ ੤ࢎਊࢿਸ ՑযৢܻҊ
    
    
    ࠁ׮ ؊ উ੿੸ਵ۽ ೐۽Ӓې߁ਸ ೞҊ र׮ݶ?
    Ҋରೣࣻܳ ഝਊೞח ё୓(ё୓ ஶప੉ց)੄
    
    
    ౠࢿਸ ঌҊ, ੉ܳ ഝਊೞݶ ػ׮
    

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39. Category Theory
    Ҋରೣࣻܳ ഝਊೞৈ ࢜۽਍ ఋੑ/ӝמਸ ઁҕೞӝ ਤ೧ࢶ
    
    
    ੉ܳ ҳࢿೞח ఋੑী ؀೧ ঌইঠ ೠ׮.
    

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40. ೣࣻഋী ੸੺ೠ “ஶప੉ց"
    Monad
    

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41. ೣࣻഋী ੸੺ೠ “ஶప੉ց"
    Monadח ূبಔఠ ஠పҊܻ੄ ݽ֢੉٘
    Monad
    

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42. ೣࣻഋী ੸੺ೠ “ஶప੉ց"
    Monadח ূبಔఠ ஠పҊܻ੄ ݽ֢੉٘
    Monad
    

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43. Category Theory
    ߧ઱ۿ
    (
    Category Theory)ীࢲח ҳઑ୓
    (
    Object)৬
    
    
    ҳઑ୓ٜр੄ ҙ҅
    (
    Morphism, ࢎ࢚)ܳ ׮ܘ׮
    

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44. Functor
    ف ஠పҊܻ р੄ ೣࣻ੉Ҋ
    
    
    ҳઑ୓ח ҳઑ୓۽, ೣࣻח ೣࣻ۽ ؀਽दఃח ೣࣻ
    

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45. Functor
    ੉۞ݶ য٣ࢲ ݆੉ࠄ Ѫ э૑ ঋաਃ?
    

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46. Functor
    

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47. Functor੄ ઺୏ ޙઁ
    

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48. Monoid
    ਤ੄ ࢿ૕ਸ ݅઒ೞח ஠పҊܻ
    

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49. Monoid
    ਤ੄ ࢿ૕ਸ ݅઒ೞח ஠పҊܻ
    
    
    (ো࢑઺ যו ੌࠗ࠙ਸ ݢ੷ ࣻ೯ೞ؊ۄب ҡଳ׮ ੿ب੄ ੄޷)
    

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50. Monad
    

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51. Monad
    

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52. Monad
    ੉ ࢿ૕ਸ ഝਊೞৈ ઺୏ػ ఋੑਸ ߩӡ ࣻ ੓׮
    

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53. Monad
    flatMap ೣࣻܳ ࢤп೧ࠁ੗!
    

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54. Monad
    Nested Optional۽ оٙସ؍ ௏٘ب
    

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55. Monad
    

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56. Monad ਽ਊ: ৈ۞ ா੉झܳ ೠ ଃਵ۽
    

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57. Monad ਽ਊ: ৈ۞ ா੉झܳ ೠ ଃਵ۽
    ী۞ ߊࢤ द ী۞ ఋੑਸ Monad ఋੑਵ۽ ೠߣ ؊ хऱળ׮ݶ?
    

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58. Monadܳ ഝਊೠ ࢚క ୊ܻ੄ ੉੼
    Monad ղࠗ ࢚కܳ ইח Ѫҗ ࢚ҙহ੉
    
    
    ѐߊ੗о ۽૒ਸ ୓੉׬೧ب ޙઁо হب۾ ୊ܻ
    
    
    ೡ ࣻ ੓׮
    

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59. Monad is Everywhere
    Spring Reactor(Mono)
    

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60. Monad is Everywhere
    RxJava (Kotlin)
    

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61. Monad is Everywhere
    

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62. Monad is Everywhere
    Kotlin Result
    

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63. Monad is Everywhere
    Compose Modifier
    

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64. Thanks!
    @l2hyunwoo
    
    
    KotlinConf’23 Global in Songdo
    
    
    Mathpresso Inc. Android/React Native Developer
    Slido
    

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