[SE-0160] Limiting @objc inference

2017/04/13(木) Potatotips #39

Transcript

1. [SE-0160]
   Limiting @objc
   inference
   Daiki Matsudate (@d_date)
   potatotips #39
   

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5. Agenda
   • ͱͯ΋140จࣈͰ͸πΠʔτͰ͖ͳ͍
   • [SE-0160] Limiting @objc inferenceʹ͍ͭͯ
   ࿩͠·͢ɻ
   

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6. [SE-0160] @objcਪ࿦ͷ੍ݶ
   • https://github.com/apple/swift-evolution/
   blob/master/proposals/0160-objc-
   inference.md
   

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7. @objc in Swift 3.x
   • Objective-CͰݺͼग़ͤΔ΋ͷʹ͍ͭͯɺSwift
   ଆͰ໌ࣔతʹએݴͰ͖Δ
   • Θ͟Θ͟@objcΛॻ͔ͳͯ͘΋͍͍Α͏ʹ
   ਪ࿦ͯ͘͠ΕΔ
   

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8. @objc in Swift 3.x ͷ໰୊఺
   • Objective-CͰݺͼग़ͤΔ΋ͷʹ͍ͭͯɺSwift
   ଆͰ໌ࣔతʹએݴͰ͖Δ
   • Θ͟Θ͟@objcΛॻ͔ͳͯ͘΋͍͍Α͏ʹ
   ਪ࿦ͯ͘͠ΕΔ → ա৒Ͱ͸ʁʁ
   

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9. @objc in Swift 3.x ͷ໰୊఺
   • SwiftͷΫϥε͸Objective-CͷSelectorͷিಥΛ
   Ҿ͖ى͕ͪ͜͠
   

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10. @objc in Swift 3.x ͷ໰୊఺
    • Swift API Design GuidelineʹԊͬͯॻ͍ͯ΋ɺ
    Objective-CͰݺͼग़͢ͱ͖ʹ͸Objective-C
    Coding Guidelineʹ൓͢Δ໊લʹม׵͞Ε͕ͪɻ
    ಛʹɺinitializer͸ɺͦͷ໊લʹୈҰҾ਺ΛؚΊͳ
    ͯ͘͸͍͚ͳ͍ͷͰɺ@objc͸ඞ͚ͣͭΔ͜ͱʹ
    ͳΔɻ
    

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11. • SwiftίϯύΠϥ͸Objective-C Calling
    Convention͔ΒSwift Calling Convention΁ม׵
    ͢Δ"thunk"ϝιουΛ࡞ΔͨΊɺόΠφϦαΠζ
    ͕૿େ͢Δɻ
    @objc in Swift 3.x ͷ໰୊఺
    

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12. @objc in future
    

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13. @objc in future
    Objective-CͰඞཁͳͱ͜Ζ͚ͩʹ@objcΛ
    ͚ͭΔΑ͏ʹਪ࿦ΛݮΒ͢
    ʲํ਑ʳ
    

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14. Ҿ͖ଓ͖@objcΛਪ࿦͢Δ΋ͷ
    1.@objcͷ͍͍ͭͯΔએݴͷΦʔόʔϥΠυͷͱ͖
    

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15. Ҿ͖ଓ͖@objcΛਪ࿦͢Δ΋ͷ
    2. @objcͷ͍ͭͨϓϩτίϧͷཁ݅Λຬͨ͢ͱ͖
    

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16. Ҿ͖ଓ͖@objcΛਪ࿦͢Δ΋ͷ
    3. @IBOutlet,@IBActionଐੑ͕͍͍ͭͯΔͱ͖
    4. @NSManagedଐੑ͕͍͍ͭͯΔͱ͖
    Interface BuilderͱͷΠϯλϥΫγϣϯ͕
    Objective-CϥϯλΠϜͰߦΘΕΔͨΊ
    Core DataͱͷΠϯλϥΫγϣϯ͕
    Objective-CϥϯλΠϜͰߦΘΕΔͨΊ
    

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17. ௥ՃͰ@objcΛਪ࿦͢Δ΋ͷ
    1. @GKInspectableଐੑ͕͍͍ͭͯΔͱ͖
    2. @IBInspectableଐੑ͕͍͍ͭͯΔͱ͖
    GameplayKitͱͷΠϯλϥΫγϣϯ͕
    Objective-CϥϯλΠϜͰߦΘΕΔͨΊ
    Interface BuilderͱͷΠϯλϥΫγϣϯ͕
    Objective-CϥϯλΠϜͰߦΘΕΔͨΊ
    

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18. @objcΛਪ࿦͠ͳ͘ͳΔ΋ͷ
    1. dynamic
    

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19. @objcΛਪ࿦͠ͳ͘ͳΔ΋ͷ
    2. NSObject༝དྷͷΫϥε
    NSObjectΛܧঝ͍ͯ͠ΔΫϥεͰ͋ͬͯ΋ɺ
    @objcͳ͠Ͱ͸Objective-C͔Βݺͼग़ͤͳ͍ɻ
    

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20. @objcΛਪ࿦͠ͳ͘ͳΔ΋ͷ
    2. NSObject༝དྷͷΫϥε
    extensionͰ͸ɺ@objcͳ͠Ͱ͸Objective-C͔Βݺͼ
    ग़ͤͳ͍ɻ
    

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21. @objcMembersͷಋೖ
    XCTestͳͲɺΫϥεશମ͕@objcͰ͋Δ͜ͱ͕ٻΊΒ
    ΕΔࡍ͸ɺ@objcMembersΛ͚ͭΔ
    

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22. @objcMembersͷಋೖ
    @objcMembersΛ͚ͭΔΫϥε͸ɺObjecive-Cଆ
    Ͱ swift_objc_membersΛ͚ͭΔ
    

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23. Extensionʹ͓͚Δ@objcͷON/OFF
    @nonobjcΛextensionʹ͚ͭΔ͜ͱͰɺ@objcͷ
    ର৅֎ͱ͢Δ͜ͱ͕Ͱ͖Δɻ
    

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24. Swift 4Ҡߦͷͱ͖͸
    Ͳ͏͢Ε͹͍͍ͷ…ʁ
    

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25. "Minimal" migration
    workflow
    

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26. Minimal migration workflow
    • Step 1:
    Swift 4ϞʔυͰɺ@objcਪ࿦͞ΕͨՕॴͷ͢΂
    ͯͷܯࠂΛղফ͢Δɻ
    

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27. Minimal migration workflow
    • Step 2:
    SWIFT_DEBUG_IMPLICIT_OBJC_ENTRYPOINTΛ1ʙ3
    ͷؒͷ஋ʹઃఆ͠ɺΞϓϦΛςετɻ
    1.ΤϯτϦϙΠϯτ΁ͷݺग़ΛϝοηʔδͰه࿥
    2.ϩάΛͱΓɺόοΫτϨʔεΛൃߦ
    3.όοΫτϨʔεͰه࿥͠ɺΫϥογϡ͠·͢ɻ
    

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28. Minimal migration workflow
    • Step 3:
    ͜ͷ࣌఺ͰɺSwift 4ʹҠߦՄೳɻSwift 4ΛϏϧ
    υ͢Δͱɺഇࢭ༧ఆͷϧʔϧʹج͍ͮͯ@objc
    ͕ਪଌ͞Εͨ࢒ΓͷέʔεͷObjective-CΤϯτ
    ϦϙΠϯτ͕࡟আ͞ΕΔɻ
    

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29. ·ͱΊ
    • dynamic, NSObject༝དྷͷΫϥεͰ͸@objcਪ࿦
    ͕͞Εͳ͘ͳΔ
    • @objcMembersʹΑΓclassશମʹ@objcΛదԠ
    Ͱ͖ΔΑ͏ʹͳΔ
    • @nonobjcΛextensionʹదԠ͢Δ͜ͱͰͦͷ
    extension͸@objcͷదԠ֎ͱ͢Δ͜ͱ͕Ͱ͖Δ
    

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30. એ఻
    

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31. Thank you
    

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