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標準ライブラリ遊び
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1. 4XJGUͰ
 ؾ࣋ͪྑ͘։ൃ͢Δ
   !)FBMUI
   4XJGU
   .FFUVQ 
   F[VSB
2. 4XJGU
   ͷදݱྗɺؾ࣋ͪྑ͍ʂʂ
3. 5...2
4. print(self) • ៸໘༑߳ (ezura) • ޷͖ͳ΋ͷ: protocol, enum • τϥΠϑΥʔτۈ຿ • twitter: @eduraaa
5. Ұϲ݄΄Ͳલʹ
   4XJGU
   Ѫ޷ձͱ͍͏ษڧձͰ
 ͓࿩͍͍ͤͯͨͩͨ͜͠͞ͱ
6. https://speakerdeck.com/ezura/swift-falseshi-jie-guan-to-sofalsezhi-xu 4XJGU
   ͷੈք؍ͱͦͷடং 4XJGU
   ͷඪ४ϥΠϒϥϦ
   ͱͷ஥ྑ͘ͳΓํ
7. for element in [1, 2, 3] { /* do something */ } [1, 2, 3].forEach { _ in /* do something */ } 1 ... 3 if array.isEmpty { /* do something */ } SequenceType
 (CollectionType) ForwardIndexType BooleanType Comparable IntegerLiteral
 Convertible ArrayLiteral
 Convertible
8. 4XJGU
   Λܗ࡞Δཁૉɺඪ४ϥΠϒϥϦ ཧղ͢Ε͹ Swift ʹௐ࿨ͨ͠ίʔυΛؾ࣋ͪྑ͘ॻ͚ͦ͏ʂ
9. 
   ෼Ͱඪ४ϥΠϒϥϦͱ༡ΜͰΈΑ͏
10. 5 ͔Β 2 ͷൣғ
 (Range) 5...2
11. for index in 1...5 { print("\(index) times 5 is \(index * 5)") } let names = ["Anna", "Alex", "Brian", "Jack"] let count = names.count for i in 0..<count { print("Person \(i + 1) is called \(names[i])") } 3BOHF
12. TUSVDU
    3BOHF&MFNFOU
    
    'PSXBSE*OEFY5ZQF
    *OU
    ͸
    'PSXBSE*OEFY5ZQF
    
 ʹ४ڌ͍ͯ͠ΔͷͰѻ͑ͨ ݫີʹ͸ɺ*OU
    4JHOFE*OUFHFS5ZQF
    Ͱ͢ɻ
 ܧঝؔ܎͸
    4JHOFE*OUFHFS5ZQF
    
    *OUFHFS5ZQF
    
    3BOEPN"DDFTT*OEFY5ZQF
    
    #JEJSFDUJPOBM*OEFY5ZQF
    
    'PSXBSE*OEFY5ZQF 1...10 &MFNFOU
13. Represents a discrete value in a series QSPUPDPM
    'PSXBSE*OEFY5ZQF Value Value Value … …
14. Represents a discrete value in a series QSPUPDPM
    'PSXBSE*OEFY5ZQF 5 6 7 … … Equatable
 +
 func successor() -> Self
15. ࣗ࡞ͷܕʹ
    'PSXBSE*OEFY5ZQF
    Λ
 ४ڌͤ͞Δྫ
16. enum Week { case Sunday, Monday, Tuesday, Wednesday, Thursday, Friday, Saturday } extension Week: ForwardIndexType { // ͜ͷ৔߹ͷ enum ͸ Hashable ʹ҉໧తʹ४ڌ͠·͢ɻ // protocol Hashable : Equatable ͳͷͰ͢Ͱʹ Equatable ʹ४ڌࡁΈͰ͢ɻ
    func successor() -> Week { switch self { case .Sunday: return .Monday case .Monday: return .Tuesday case .Tuesday: return .Wednesday case .Wednesday: return .Thursday case .Thursday: return .Friday case .Friday: return .Saturday case .Saturday: return self // ऴ୺ } } } 'PSXBSE*OEFY5ZQF
    ྫ Sunday Monday Tuesday … Saturday 8FFL
17. enum Week { case Sunday, Monday, Tuesday, Wednesday, Thursday, Friday, Saturday } extension Week: ForwardIndexType { // ͜ͷ৔߹ͷ enum ͸ Hashable ʹ҉໧తʹ४ڌ͠·͢ɻ // protocol Hashable : Equatable ͳͷͰ͢Ͱʹ Equatable ʹ४ڌࡁΈͰ͢ɻ
    func successor() -> Week { switch self { case .Sunday: return .Monday case .Monday: return .Tuesday case .Tuesday: return .Wednesday case .Wednesday: return .Thursday case .Thursday: return .Friday case .Friday: return .Saturday case .Saturday: return self // ऴ୺ } } } Week.Friday == Week.Friday // true (Week.Monday ... .Friday).contains(.Wednesday) // true 'PSXBSE*OEFY5ZQF
    ྫ
18. Ұ࿈ͷۭؒͷதͷ཭ࢄ஋ Sunday Monday Tuesday … Saturday ͜ͷੑ࣭Λදݱ͢ΔͨΊͷཁ݅
    
    l࣍ͷ஋Λࣔ͢z
19. enum Week { case Sunday, Monday, Tuesday, Wednesday, Thursday, Friday, Saturday } extension Week: ForwardIndexType { // ͜ͷ৔߹ͷ enum ͸ Hashable ʹ҉໧తʹ४ڌ͠·͢ɻ // protocol Hashable : Equatable ͳͷͰ͢Ͱʹ Equatable ʹ४ڌࡁΈͰ͢ɻ func successor() -> Week { switch self { case .Sunday: return .Monday case .Monday: return .Tuesday case .Tuesday: return .Wednesday case .Wednesday: return .Thursday case .Thursday: return .Friday case .Friday: return .Saturday case .Saturday: return .Sunday // ࠷ॳʹ໭Δ } } } (Week.Saturday ... .Monday).contains(.Sunday) // true 'PSXBSE*OEFY5ZQF
    ྫ Sunday Monday Tuesday … Saturday
20. 5...2 ͭ͡͸ɻɻ
21. let loopRange: Range<LoopIndex> = 5...2 ͭ͡͸ɻɻ ࣗ࡞ͷܕ
22. let loopRange: Range<LoopIndex> = LoopIndex(5)...LoopIndex(2) ͭ͡͸ɻɻ ࣗ࡞ͷܕ
23. let loopRange: Range<LoopIndex> = ͭ͡͸ɻɻ ࣗ࡞ͷܕ 5...2 extension LoopIndex : IntegerLiteralConvertible ॳظԽ࣌ʹ
 ੔਺ϦςϥϧΛड͚औΕΔ
24. Conforming types can be initialized with integer literals. QSPUPDPM
    *OUFHFS-JUFSBM$POWFSUJCMF
25. struct LoopIndex { let rawValue: Int init(_ rawValue: Int) { self.rawValue = rawValue } } // OK let loopIndex = LoopIndex(1) // ௨ৗ͸Ͱ͖ͳ͍ // error: cannot convert value of type 'Int' to specified type 'LoopIndex' let beforeConform: LoopIndex = 5 -PPQ*OEFY
    ࣗ࡞ͷܕ
26. struct LoopIndex { let rawValue: Int init(_ rawValue: Int) { self.rawValue = rawValue } } extension LoopIndex: IntegerLiteralConvertible { init(integerLiteral value: IntegerLiteralType) { self.init(value) } } let loopIndex: LoopIndex = 1 -PPQ*OEFY
    *OUFHFS-JUFSBM$POWFSUJCMF 0,
27. struct LoopIndex { let rawValue: Int init(_ rawValue: Int) { self.rawValue = rawValue } } extension LoopIndex: IntegerLiteralConvertible { init(integerLiteral value: IntegerLiteralType) { self.init(value) } } extension LoopIndex: ForwardIndexType { // ུ } let loopIndex: LoopIndex = 1 let loopRange : Range<LoopIndex> = 5...2 loopRange.contains(1) // true -PPQ*OEFY
    *OUFHFS-JUFSBM$POWFSUJCMF 0,
28. let loopRange: Range<LoopIndex> = 5...2
29. 5...2 ஫
    τϦοΩʔͳ͜ͱΛ͢Δͱ͖͸৻ॏʹʂʂ
30. ͪΐͬͱৼΓฦͬͯΈ·͠ΐ͏
31. QSPUPDPM
    'PSXBSE*OEFY5ZQF
    QSPUPDPM
    *OUFHFS-JUFSBM$POWFSUJCMF
32. enum Week { case Sunday, Monday, Tuesday, Wednesday, Thursday, Friday, Saturday } 8FFL Sunday Monday Tuesday … Saturday 8FFL
33. enum Week { case Sunday, Monday, Tuesday, Wednesday, Thursday, Friday, Saturday } extension Week: ForwardIndexType { // ͜ͷ৔߹ͷ enum ͸ Hashable ʹ҉໧తʹ४ڌ͠·͢ɻ // protocol Hashable : Equatable ͳͷͰ͢Ͱʹ Equatable ʹ४ڌࡁΈͰ͢ɻ
    func successor() -> Week { switch self { case .Sunday: return .Monday case .Monday: return .Tuesday case .Tuesday: return .Wednesday case .Wednesday: return .Thursday case .Thursday: return .Friday case .Friday: return .Saturday case .Saturday: return self // ऴ୺ } } } 8FFL
    'PSXBSE*OEFY5ZQF Sunday Monday Tuesday … Saturday 8FFL
34. struct LoopIndex { let rawValue: Int init(_ rawValue: Int) { self.rawValue = rawValue } } // OK let loopIndex = LoopIndex(1) // ௨ৗ͸Ͱ͖ͳ͍ // error: cannot convert value of type 'Int' to specified type 'LoopIndex' let beforeConform: LoopIndex = 5 -PPQ*OEFY
    ࣗ࡞ͷܕ
35. struct LoopIndex { let rawValue: Int init(_ rawValue: Int) { self.rawValue = rawValue } } extension LoopIndex: IntegerLiteralConvertible { init(integerLiteral value: IntegerLiteralType) { self.init(value) } } let loopIndex: LoopIndex = 1 -PPQ*OEFY
    *OUFHFS-JUFSBM$POWFSUJCMF -PPQ*OEFY 1
36. struct LoopIndex { let rawValue: Int init(_ rawValue: Int) { self.rawValue = rawValue } } extension LoopIndex: IntegerLiteralConvertible { init(integerLiteral value: IntegerLiteralType) { self.init(value) } } let loopIndex: LoopIndex = 1 -PPQ*OEFY
    *OUFHFS-JUFSBM$POWFSUJCMF -PPQ*OEFY 1
37. ⭕
    ࢖͑Δػೳ͕૿͑Δ
38. ΋ͬͱخ͍͜͠ͱ
39. ϓϩτίϧʹ४ڌ͢Δ͜ͱͰ
 ܕ͕ද֓͢೦ΛΑΓ໌֬ʹදݱͰ͖Δʂ
40. enum Week { case Sunday, Monday, Tuesday, Wednesday, Thursday, Friday, Saturday } extension Week: ForwardIndexType { // ͜ͷ৔߹ͷ enum ͸ Hashable ʹ҉໧తʹ४ڌ͠·͢ɻ // protocol Hashable : Equatable ͳͷͰ͢Ͱʹ Equatable ʹ४ڌࡁΈͰ͢ɻ
    func successor() -> Week { switch self { case .Sunday: return .Monday case .Monday: return .Tuesday case .Tuesday: return .Wednesday case .Wednesday: return .Thursday case .Thursday: return .Friday case .Friday: return .Saturday case .Saturday: return self // ऴ୺ } } } 8FFL
    'PSXBSE*OEFY5ZQF Sunday Monday Tuesday … Saturday 8FFL
41. struct LoopIndex { let rawValue: Int init(_ rawValue: Int) { self.rawValue = rawValue } } extension LoopIndex: IntegerLiteralConvertible { init(integerLiteral value: IntegerLiteralType) { self.init(value) } } let loopIndex: LoopIndex = 1 -PPQ*OEFY
    *OUFHFS-JUFSBM$POWFSUJCMF -PPQ*OEFY 1
42. ͝ਗ਼ௌ͋Γ͕ͱ͏͍͟͝·ͨ͠
43. ࢀߟ w 4XJGU
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    3FGFSFODF
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    w Ϧςϥϧͱܕͷ࿩
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