Opaque Result Type with type system

Transcript

1. .PCJMF"DU,:050
   Opaque Result Type
   Λͻ΋ͱ͘
   

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2. w ਗ਼ਫ୓ຏ
   w!IPLVSPO
   wυϝΠϯۦಈઃܭ
   w J04
   w 3VCZPO3BJMT
   w 3VTU
   wϑΣϯϦϧגࣜձࣾ
   

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3. Opaque Result Type
   Λͻ΋ͱ͘
   

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4. IUUQTRJJUBDPNLPIFSJUFNTEGEDFG
   

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6. ෮श
   .PCJMF"DU04","ΑΓ
   

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7. Opaque Argument Type
   w Ҿ਺ͷ৔ॴʹҐஔ͢Δsome Protocol
   w ௨ৗͷHFOFSJDTͱಉ͡ৼΔ෣͍
   w TQFDJBMJ[BUJPO
   w ݺͼग़͠ଆ͕۩ମతͳܕΛܾఆ
   

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8. Opaque Argument Type
   // generics
   func useAnimal(_ animal: A) {
   animal.foo()
   }
   // Opaque Argument Type
   func useAnimal(_ animal: some Animal) {
   animal.foo()
   }
   㲈
   ಉ౳ ˡͳΜͰʁ
   

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9. ྔԽ
   2VBOUJpDBUJPO
   

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10. func useAnimal(_ animal: A) {
    animal.foo()
    }
    ∀ A. (func(A: Animal) -> ())
    䁭
    શশྔԽܕ
    func(∃ A. A: Animal) -> ()
    䁭
    ଘࡏྔԽܕ
    func useAnimal(_ animal: some Animal) {
    animal.foo()
    }
    

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11. (∀ x. (P(x) → Q))
    䁭
    શশྔԽܕ
    ((∃ x. P(x)) → Q)
    䁭
    ଘࡏྔԽܕ
    ∀ A. (func(A: Animal) -> ())
    func(∃ A. A: Animal) -> ()
    

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12. (∀ x. (P(x) → Q)) ((∃ x. P(x)) → Q)
    㱻
    㱻
    ͜ͷه߸͸ʮಉ஋ʯͷҙຯͰ͢
    

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13. Opaque Argument Type
    w HFOFSJDT શশྔԽ
    ͱΑ͘ࣅͨߏ଄Λ࣋ͭ
    w Ϣχόʔαϧ ීวɾશশ
    ʹ͸ͳΒͳ͍
    w useAnimal(a: T)ͱಉ͜͡ͱ͕Ͱ͖ͳ͍
    w useAnimal(a: some T)ͱ͸ॻ͚ͳ͍
    w ಛఆͷ࣮ࡏ ଘࡏ
    ͢ΔܕΛඞͣ࣋ͭ ଘࡏྔԽ
    
    

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14. Opaque Result Type
    Λͻ΋ͱ͘
    

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15. func(∃ A. A: Animal) -> ()
    䁭
    ଘࡏྔԽܕ
    func useAnimal(_ animal: some Animal)
    Opaque Argument Type
    func useAnimal(_ animal: A)
    ∀ A. (func(A: Animal) -> ())
    䁭
    શশྔԽܕ
    

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16. func(∃ A. A: Animal) -> ()
    䁭
    ଘࡏྔԽܕ
    func useAnimal(_ animal: some Animal)
    Opaque Argument Type
    func useAnimal(_ animal: A)
    ∀ A. (func(A: Animal) -> ())
    䁭
    શশྔԽܕ
    

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17. func() -> (∃ A. A: Animal)
    䁭
    ଘࡏྔԽܕ
    func makeAnimal() -> some Animal
    Opaque Result Type
    func makeAnimal(_: A) -> A
    ∀ A. (func(A: Animal) -> A)
    䁭
    શশྔԽܕ
    

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18. func() -> (∃ A. A: Animal)
    䁭
    ଘࡏྔԽܕ
    func makeAnimal() -> some Animal
    Opaque Result Type
    func makeAnimal(_: A) -> A
    ∀ A. (func(A: Animal) -> A)
    䁭
    શশྔԽܕ
    

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19. ଘࡏྔԽܕ
    w ه߸ʹྡ઀͢ΔQSPUPDPM΁ͷ ܕ
    ੍໿ͷΈ͕είʔϓ
    w func(∃ A. A: Animal) -> ()
    w func() -> (∃ A. A: Animal)
    w ྔԽܕߏจͷ؍఺Ͱ͸ہॴత
    

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20. Opaque Result Type
    w ฦ٫஋ͷ৔ॴʹҐஔ͢Δsome Protocol
    w 3FWFSTFHFOFSJDT
    w TQFDJBMJ[BUJPO
    w ݺͼग़͞ΕΔଆ ࣮૷ଆ
    ͕۩ମతͳܕΛܾఆ
    w SFUVSO͢ΔΦϒδΣΫτͷܕ͸ಈతʹม͑ΒΕͳ͍
    

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21. func makeAnimal() -> some Animal {
    return flag ? Dog() : Cat()
    }
    ͜͏ॻ͘͜ͱ͸Ͱ͖ͳ͍
    ະ֬ೝͰ͕͢QSPQPTBMΛݟΔݶΓແཧͳ͸ͣʜ
    
    "OJNBMʹ४ڌ͍ͯͯ͠΋
    ฦ٫Ͱ͖ΔΠϯελϯεͷܕ͸ͻͱ͚ͭͩ
    

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22. w HFOFSJDT
    w ίϯύΠϥ͸Ͳͷܕ͕ฦ͞ΕΔͷ͔஌͓ͬͯ͘ඞཁ͕͋Δ
    w ଘࡏ ྔԽ
    ܕ͸࣮ߦ࣌Ͱ͸ଘࡏ͠ͳ͍
    w ४ڌͨ͠۩৅ܕʹஔ͖׵͑ΒΕΔ
    Reverse generics
    

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23. ଘࡏྔԽ
    w ྔԽܕͷදݱͱ͸ରরతʹɺଘࡏྔԽ͕

    ؔ਺ ϝιου
    શମΛείʔϓʹऔ͍ͬͯΔ
    w ࣮ࡍɿfunc() -> (∃ A. A: Animal)
    w ײ֮ɿ∃ A. (func() -> (A: Animal))
    w any Protocol΍Opaque Argument Type͸

    ଘࡏྔԽܕΛͦͷ··දݱͯͦ͠͏
    &YJTUFOUJBM$POUBJOFSΛ
    ߟྀ͠ͳ͚Ε͹ʜ
    

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24. Opaque Result Type
    w some Protocol͸୯Ұͷ۩৅ ඇྔԽ
    ܕͷΈ࢖͑Δ
    w ࣮ߦ࣌ʹଘࡏ͠ͳ͍ଘࡏܕ
    w ྔԽදݱͱ࣮ࡍͷৼΔ෣͍͕Ұக͠ͳ͍
    w 0QBRVF"SHVNFOU5ZQFͱҟͳΔηϚϯςΟοΫΛ࣋ͭ
    w ίʔυॻ͍ͯΔͱ͖ʹˢͦΜͳ͜ͱؾʹ͠ͳ͍
    

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25. Opaque Result Type
    Λ׆༻͠·͠ΐ͏ʂ
    

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26. ͝੩ௌ͋Γ͕ͱ͏͍͟͝·ͨ͠
    

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