あんまり触れられてない気がする、Kotlin1.3の ありがたい追加機能

2018年11月29日（木）にYahoo LODGEで開催された筋肉.ktの資料です

Transcript

1. ͋Μ·Γ৮ΕΒΕͯͳ͍
   ؾ͕͢ΔɺKotlin1.3ͷ
   ͋Γ͕͍ͨ௥Ճػೳ
   @yamacraft
   

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2. profile
   • @yamacraft
   • Mobile Application Engineer
   • Freelance / (private)team Y.G.E.
   • Getting Over Itɹˠˠˠ
   • 130↑wins / BestTime 8min
   

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3. trainingʢonly machineʣ
   • νΣετϓϨε 70ʙ80kg 4ʙ6rep * 3
   • ϩʔσϧτΠυ 65ʙ75kg 4ʙ6rep * 3
   • ϓϧμ΢ϯ 75kg 4ʙ6rep * 3
   • ϨοάϓϨε 125ʙ135kg 4ʙ6rep * 3
   • and more
   

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4. physical
   https://athletebody.jp/2017/10/31/skill-level-assessment/
   

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5. trouble
   • Ϛγϯ͚ͩͩͱѲྗ͸શવ͔ͭͳ͍
   • CoC #1͕ด͡ΒΕͳͯ͘ԜΜͩ
   • όοΫΤΫεςϯγϣϯ͕δϜʹͳ͍
   • δϜͷϑϦʔ΢ΣΠτκʔϯ͕ڱ͗͢Δ
   

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6. Kotlin 1.3Ͱ௥Ճ͞Εͨ
   ͪΐͬͱخ͍͠ػೳͷ঺հ
   https://kotlinlang.org/docs/reference/whatsnew13.html
   

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7. ͦͷલʹ
   

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8. ৽ػೳͷνΣοΫͬͯ
   Ͳ͏΍ͬͯ֬ೝ͠·͔͢ʁ
   

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9. UnitTestͰࢼ͢ͷ͕͓͢͢Ί
   ※ॾઆ͋Γ·͢
   

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10. ຊ୊ʹ໭Γ·͢
    

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11. Kotlin 1.3Ͱ௥Ճ͞Εͨ
    ͪΐͬͱخ͍͠ػೳͷ঺հ
    https://kotlinlang.org/docs/reference/whatsnew13.html
    

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12. RandomAPIͷ௥Ճ
    • kotlin.random.Random͕௥Ճ͞Εͨ
    • ཚ਺ੜ੒ʹjava.util.*Λར༻͠ͳͯ͘ࡁΉΑ͏
    ʹͳͬͨ
    • java.util.Randomಉ༷ʹɺ֤ܕͰग़ྗՄೳ
    • Kotlin Native͋ͨΓ͸͋Γ͕͍ͨ͸ͣ
    

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13. RandomAPIͷ௥Ճ
    

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14. ίϨΫγϣϯܥʹ
    isNullOrEmpty()ͷ௥Ճ
    • Stringʹ͋ͬͨisNullOrEmpty()͕Collection΍
    ListɺmapͳͲͰར༻Մೳʹͳͬͨ
    • isEmpty()ͳΒલ͔Β͋Γ·ͨ͠
    • nullνΣοΫ΋·ͱΊͯͰ͖ͯେม͋Γ͕͍ͨ
    

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15. ίϨΫγϣϯܥʹ
    isNullOrEmpty()ͷ௥Ճ
    

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16. unsignedʢූ߸ͳ͠ʣܕͷ
    ௥Ճ
    • UByte … 0ʙ255
    • UShort … 0ʙ65535
    • UInt … 0ʙ2^32-1
    • ULong … 0ʙ2^64-1
    • ਓʹΑͬͯ͸ϝνϟΫνϟ͋Γ͕͍ͨ…
    

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17. unsignedʢූ߸ͳ͠ʣܕͷ
    ௥Ճ
    

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18. ifEmpty()ɺifBlankͷ௥Ճ
    • if(x.isEmpty){}ͱ΍Βͣʹɺx.ifEmpty{}Ͱۭ΍
    ۭന࣌ͷॲཧ͕͍͖ͳΓॻ͚ΔΑ͏ʹͳͬͨ
    • kotlinΆ͘ͳͬͯ͋Γ͕͍ͨ
    

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19. ifEmpty()ɺifBlankͷ௥Ճ
    

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20. ଞʹ΋͍Ζ͍Ζ͋ΔͷͰ
    νΣοΫͯ͠ΈΑ͏ʂ
    https://kotlinlang.org/docs/reference/whatsnew13.html
    

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21. ͓͠·͍
    

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