Introducing Function Builder

potatotips #267
2019/12/17

Transcript

1. Introducing Function Builder
   potatotips #267
   2019/12/17
   

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2. Akihisa Sengoku
   @akihisasen
   גࣜձࣾαΠόʔΤʔδΣϯτ
   AmebaʢΞϝʔόʣ
   iOSΤϯδχΞ
   

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3. Function Builderͱ͸ʁ
   

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4. 4XJGU6*Ͱ࢖ΘΕ͍ͯΔΫϩʔδϟʔతͳ΋ͷʁ
   

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5. %4-Λॻ͘͜ͱ͕Ͱ͖ΔΑ͏ʹͳͬͨʁ
   

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6. 4XJGUͰ௥Ճ͞Εͨ৽ػೳ
   1SPQPTBM 'PSVN
   

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7. Builderͷϧʔϧʹैͬͯؔ਺Λ
   ҉໧తʹม׵͢Δ͜ͱ͕Ͱ͖Δ
   #VJMEFSΛ
   దԠͨؔ͠਺
   #VJMEFSϧʔϧʹ
   Ԡͯؔ͡਺Λม׵
   #VJMEFSΛఆٛ
   #VJMEFSΛ
   దԠ
   

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10. Function BuilderʹΑΓ
    ಠࣗͷDSLΛΑΓ࡞੒͠΍͘͢ͳͬͨ
    - Structure Data (json, XML)
    - UI View Hierarchies
    - HTML DOM Hierarchies
    

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11. ࡞Γํ!
    

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12. #VJMEFSͷ࡞੒ํ๏ʹ͍ͭͯ
    

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13. Builderͷ࡞੒ํ๏
    1. struct or classͷલʹ`@_functionBuilder`Λ͚ͭͯ
    ఆٛ͢Δɻ
    2. static func Ͱ `buildBlock(_ components:
    Component...) -> Component` Λఆٛ͢Δɻ
    

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14. ͦͷଞͷbuildͷ࣮૷
    • buildExpression(_ expression: Expression) ->
    Component
    • buildFunction(_ components: Component...) -
    > Return
    • buildDo(_ components: Component...) ->
    Component
    • buildOptional(_ component: Component?) ->
    Component
    

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15. 'VODUJPO#VJMEFSͷ࢖༻ํ๏
    

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16. Function Builderͷ࢖༻ํ๏
    1. Function BuilderΛ࢖༻͍ͨؔ͠਺ͷલʹ
    @FunctionBuilder໊Λ͚ͭΔ
    2. BuilderͷbuildBlockʹରԠ͢ΔҾ਺Λɺ
    վߦ۠੾ΓͰهड़
    

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17. ؔ਺ͷҾ਺ͷΫϩʔδϟͰFunction Builder
    Λ࢖༻͢Δ͜ͱ͕Ͱ͖Δ
    

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19. ϓϩμΫτಋೖ
    

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20. SwiftUI
    HTML
    NSAttributedString
    Network
    UIKit
    ϓϩμΫτಋೖ: DSL
    

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21. Amebaͷಋೖྫ
    NSAttributedStringͷIFΛ៉ྷʹ
    
    
    
    5JQT
    

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22. What's New in Swift - WWDC2019
    https://developer.apple.com/videos/play/
    wwdc2019/402/
    Function Builder - swift-evolution
    https://github.com/apple/swift-evolution/blob/
    9992cf3c11c2d5e0ea20bee98657d93902d5b17
    4/proposals/XXXX-function-builders.md
    

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