Getting_all_enum_element

potatotips #43で発表させていただいた内容です
Enumを便利に使えるマイクロライブラリを開発した話

https://potatotips.connpass.com/event/63472/

Transcript

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7. ίʔυ
8. એݴ public protocol Enumerable: RawRepresentable { static var enumerate: AnySequence<Self> { get } static var elements: [Self] { get } static var count: Int { get } static var startIndex: Int { get } }
9. ࣮૷ public extension Enumerable where RawValue == Int { public static var enumerate: AnySequence<Self> { return AnySequence { () -> AnyIterator<Self> in var i = startIndex return AnyIterator { () -> Self? in let element = Self(rawValue: i) i += 1 return element } } } public static var elements: [Self] { return Array(enumerate) } public static var count: Int { return elements.count } public static var startIndex: Int { return 0 } }
10. ࣮૷ public extension Enumerable where RawValue == Int { public static var enumerate: AnySequence<Self> { return AnySequence { () -> AnyIterator<Self> in var i = startIndex return AnyIterator { () -> Self? in let element = Self(rawValue: i) i += 1 return element } } } public static var elements: [Self] { return Array(enumerate) } public static var count: Int { return elements.count } public static var startIndex: Int { return 0 } } FMFNFOUT͸഑ྻ
11. ࣮૷ public extension Enumerable where RawValue == Int { public static var enumerate: AnySequence<Self> { return AnySequence { () -> AnyIterator<Self> in var i = startIndex return AnyIterator { () -> Self? in let element = Self(rawValue: i) i += 1 return element } } } public static var elements: [Self] { return Array(enumerate) } public static var count: Int { return elements.count } public static var startIndex: Int { return 0 } } FOVNFSBUF 4FRVFODF ͔Β࡞ΒΕΔ
12. ࣮૷ public extension Enumerable where RawValue == Int { public static var enumerate: AnySequence<Self> { return AnySequence { () -> AnyIterator<Self> in var i = startIndex return AnyIterator { () -> Self? in let element = Self(rawValue: i) i += 1 return element } } } public static var elements: [Self] { return Array(enumerate) } public static var count: Int { return elements.count } public static var startIndex: Int { return 0 } } FOVNFSBUF
13. public extension Enumerable where RawValue == Int { public static var enumerate: AnySequence<Self> { return AnySequence { () -> AnyIterator<Self> in var i = startIndex return AnyIterator { () -> Self? in let element = Self(rawValue: i) i += 1 return element } } } public static var elements: [Self] { return Array(enumerate) } public static var count: Int { return elements.count } public static var startIndex: Int { return 0 } } ͜ͷϧʔϓ͸OJMΛฦ͢ͱऴΘΓ
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14. public extension Enumerable where RawValue == Int { public static var enumerate: AnySequence<Self> { return AnySequence { () -> AnyIterator<Self> in var i = startIndex return AnyIterator { () -> Self? in let element = Self(rawValue: i) i += 1 return element } } } public static var elements: [Self] { return Array(enumerate) } public static var count: Int { return elements.count } public static var startIndex: Int { return 0 } } 4FMG SBX7BMVF*OU
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15. public extension Enumerable where RawValue == Int { public static var enumerate: AnySequence<Self> { return AnySequence { () -> AnyIterator<Self> in var i = startIndex return AnyIterator { () -> Self? in let element = Self(rawValue: i) i += 1 return element } } } public static var elements: [Self] { return Array(enumerate) } public static var count: Int { return elements.count } public static var startIndex: Int { return 0 } } ࿈൪Ͱ͋Ε͹JODSFNFOU͍͚ͯ͠͹
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16. public extension Enumerable where RawValue == Int { public static var enumerate: AnySequence<Self> { return AnySequence { () -> AnyIterator<Self> in var i = startIndex return AnyIterator { () -> Self? in let element = Self(rawValue: i) i += 1 return element } } } public static var elements: [Self] { return Array(enumerate) } public static var count: Int { return elements.count } public static var startIndex: Int { return 0 } } ࿈൪Ͱ͋Ε͹JODSFNFOU͍͚ͯ͠͹
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