swift_clean_code.pdf

Presentation about swift clean code

Transcript

1. iOSDC Japan 2019
   2019 9/6(Fri) 13:30~14:00 TrackA
   Swift
   ΫϦʔϯίʔυ
   Ξυϕϯνϟʔɹ
   ~೔ʑͷۤ೰Λ৐Γӽ͑ɺ͔֬ͳબ୒Λ͢ΔͨΊʹ~
   ը૾ͷϦϯΫ
   

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2. VISITS Technologiesגࣜձࣾ
   shiz@stzn3
   shiz(ͣ͠)
   @shiz
   stzn(shiz)
   ։ൃܦݧݴޠ:
   Swift Kotlin Javascript PHP C#
   Java Go…
   

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3. ΫϦʔϯ
   ίʔυ
   ը૾ͷϦϯΫ
   

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4. ΫϦʔϯίʔυ
   ͱ͸ʁ
   

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5. Robert C. Martin
   (Uncle Bob)
   $MFBO$PEF")BOECPPLPG"HJMF4PGUXBSF$SBGUTNBOTIJQ $MFBO$PEFɹΞδϟΠϧιϑτ΢ΣΞୡਓͷٕ
   https://blog.cleancoder.com
   

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6. ୡਓͨͪᐌ͘
   ͻͱͭͷ͜ͱΛߦͬͯҙਤ͕໌֬ ෺ޠΛಡΉΑ͏ʹಡΊΔ
   ΤϨΨϯτͰޮ཰͕ྑ͍
   ࣄ࣮ʹଈ͍ͯ͠ͳΕ͹ͳΒͳ͍
   ҙຯΛ໊࣋ͬͨલ͕͋Δ
   ґଘੑ͸࠷௿ݶͰ໌֬ʹఆٛ͞Ε͍ͯΔ
   ಡΉͷʹେ͖ͳ౒ྗ͕ඞཁͳ͍
   ڻ͖͕ͳ͍
   ॏෳΛݮΒ͠ɺදݱྗΛߴΊɺ
   ୯७ͳந৅ԽΛૣ͍࣌ظʹ࡞Γ͋͛Δ
   খ͖͜͞ͱ͸ྑ͖͜ͱ
   ݪ࡞ऀҎ֎ͷਓʹ΋ಡΉ͜ͱ͕Ͱ͖ɺ
   ֦ுͰ͖Δίʔυ
   ৗʹ୭͔͕ؾ഑ΓΛ࣋ͬͯॻ͍͍ͯΔΑ͏ʹݟ͑Δ
   Clean Code ΞδϟΠϧιϑτ΢ΣΞୡਓͷٕ Robert C. Martin(ஶ), ՖҪࢤੜ(༁)
   

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7. Uncle Bobᐌ͘
   ಡΈ΍͍͢ίʔυ
   Clean Code ΞδϟΠϧιϑτ΢ΣΞୡਓͷٕ Robert C. Martin(ஶ), ՖҪࢤੜ(༁)
   

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8. ը૾ͷϦϯΫ
   

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9. ΫϦʔϯίʔυಓ৔
   “զʑࣗ਎͕௕͍ؒɺ͔֬Ͱ͋Δ
   ͱߟ͖͑ͯͨ͜ͱͰ͢ɻԿे೥ʹ
   ౉ΔܦݧͱτϥΠΞϯυΤϥʔͷ
   ੵΈॏͶ͔ΒֶΜͩ΋ͷͰ͢ɻ”
   Clean Code ΞδϟΠϧιϑτ΢ΣΞୡਓͷٕ Robert C. Martin(ஶ), ՖҪࢤੜ(༁)
   

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10. Θ͔Γ΍͍͢
    ҆શͰ͋Δ
    มߋʹڧ͍
    

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11. Θ͔Γ΍͍͢
    ҆શͰ͋Δ
    มߋʹڧ͍
    ಡΈ΍͢͞ɺཧղͷ͠΍͢͞ etc
    όά͕ൃੜͮ͠Β͍ɺςετ͕༰қ etc
    मਖ਼࣌ͷӨڹൣғ͕ݶఆత
    ػೳ௥Ճ࣌ͷطଘίʔυ΁ͷӨڹ౓খ etc
    

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12. Kickstarter
    ߏ଄ͷ౷Ұ(ViewModel Input,Output etc)
    SingletonͰDI؅ཧ(Environment)
    ը໘ભҠͷू໿؅ཧ(Router)
    Playgroundۦಈ։ൃ
    

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13. Kickstarter ios-oss
    https://github.com/kickstarter/ios-oss
    POINT•FREE
    https://www.pointfree.co/
    objc.io iOS at Kickstarter
    https://talk.objc.io/collections/ios-at-kickstarter
    How to Control the World
    https://vimeo.com/291588126
    Reactive view models, simplified
    https://www.youtube.com/watch?v=uTLG_LgjWGA
    Kickstarter ios-ossߏ੒ͷղઆ
    https://note.mu/yimajo/n/ne44c7945279a
    RxSwiftݚڀಡຊ3 ViewModelઃܭύλʔϯೖ໳
    https://booth.pm/ja/items/1223536
    Kickstarter-iOSͷViewModelͷ࡞Γํ͕΢Ϛ͔ͬͨ
    https://qiita.com/muukii0803/items/045b12405f7acff1a9fd
    

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14. ΫϦʔϯίʔυΛ
    ॻ͘ʹ͸ʁ
    

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15. ը૾ͷϦϯΫ
    

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16. δΣωϦοΫ
    ۩ମతͳσʔλܕʹ௚઀
    ґଘͤͣ൚༻తʹར༻Մ
    ೳͳঢ়ଶ
    

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17. δΣωϦΫε
    (generics)
    GVODTXBQ5XP7BMVFT
    5 @BJOPVU
    5 @CJOPVU
    5
    
    GVODTXBQ5XP4USJOHT @BJOPVU4USJOH @CJOPVU4USJOH
    
    GVODTXBQ5XP%PVCMFT @BJOPVU%PVCMF @CJOPVU%PVCMF
    
    GVODTXBQ5XP*OUT @BJOPVU*OU @CJOPVU*OU
    
    https://docs.swift.org/swift-book/LanguageGuide/Generics.html
    

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18. Protocol
    ը૾ͷϦϯΫ
    

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19. Protocol
    ίϯύΠϧ࣌
    δΣωϦΫεͷܕ੍໿
    ܕ҆શɾ࠷దԽ
    Static
    ࣮ߦ࣌
    ௚઀ܕͱͯ͠࢖༻
    Dynamic Dispatch
    Dynamic
    func F
    (onlyOneType: P)
    let types:[Protocol]
    = [A(), B(), …]
    

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20. Protocol
    ίϯύΠϧ࣌
    δΣωϦΫεͷܕ੍໿
    ܕ҆શɾ࠷దԽ
    Static
    ࣮ߦ࣌
    ௚઀ܕͱͯ͠࢖༻
    Dynamic Dispatch
    Dynamic
    func F
    (onlyOneType: P)
    let types:[Protocol]
    = [A(), B(), …]
    

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21. Protocol
    ίϯύΠϧ࣌
    δΣωϦΫεͷܕ੍໿
    ܕ҆શɾ࠷దԽ
    Static
    ࣮ߦ࣌
    ௚઀ܕͱͯ͠࢖༻
    Dynamic Dispatch
    Dynamic
    func F
    (onlyOneType: P)
    let types:[Protocol]
    = [A(), B(), …]
    

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22. Start With
    a Protocol
    ϓϩτίϧ͔Β࢝ΊΑ
    Protocol-Oriented Programming in Swift WWDC2015
    

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23. Start With
    a Protocol
    For Everything?
    ͢΂ͯϓϩτίϧ͔Β࢝ΊΑ?
    

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24. if you want to write a
    generalized sort or
    binary search…Don’t
    start with a class. Start
    with a protocol.
    Protocol-Oriented Programming in Swift WWDC2015
    

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25. use value types, then if
    you need polymorphism,
    make them conform to
    protocols. Avoid classes.
    https://twitter.com/cocoaphony/status/1104114233288151043
    ϙϦϞʔϑΟζϜ
    ಉ໊͡લͷϝιουΛෳ਺ͷΫϥεͰ࢖༻Ͱ͖ΔΑ͏ʹ͠ɺͦͷϝ
    ιουΛ௨ͯ͠ɺ҉໧తʹෳ਺ͷΠϯελϯεͷಈ࡞Λ੾Γସ͑Δ
    ͜ͱ͕Ͱ͖ΔΑ͏ʹ͢Δ͜ͱ
    

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26. …we considered a varied number of concrete
    types first. …we’re thinking about a kind of
    protocol that could join them all together. …it’s
    important to think of things as this way around.
    To start with some
    concrete types, and then
    try and unify them with a
    protocol.
    Swift Generics (Expanded) WWDC2018
    

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27. Don’t Literally
    Start With a Protocol
    Start with a concrete use cases
    Discover a need for generic code
    Try to compose solutions from
    existing protocols first
    Consider a generic type instead of a
    protocol
    Modern Swift API Design WWDC2019
    

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28. ۩ମతղܾ
    ໰୊
    δΣωϦοΫͳղܾ
    ໰୊ ໰୊
    ໰୊
    ݸʑͷ۩ମత໰୊Λղܾ͠
    δΣωϦοΫͳղܾࡦΛநग़
    ۩ମతղܾ
    ໰୊
    

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29. ը૾ͷϦϯΫ
    

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30. struct Item: Codable {
    let id: Int
    let name: String
    }
    struct User: Codable {
    let id: Int
    let name: String
    }
    struct Client {
    let baseURL = URL(string: “…”)!
    }
    

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31. extension Client {
    func fetchItem(id: Int,
    completion: @escaping
    (Result) -> Void) {
    let urlRequest = URLRequest(url: baseURL
    .appendingPathComponent(“items")
    .appendingPathComponent("\(id)")
    )
    let session = URLSession.shared
    session.dataTask(with: urlRequest) { (data, _, error) in
    if let error = error {
    completion(.failure(error))
    } else if let data = data {
    let decoder = JSONDecoder()
    completion(Result {
    try decoder.decode(Item.self, from: data) })
    }
    }.resume()
    }
    }
    

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32. extension Client {
    func fetchItem(id: Int,
    completion: @escaping
    (Result) -> Void)
    {
    let urlRequest = URLRequest(url: baseURL
    .appendingPathComponent("items")
    .appendingPathComponent("\(id)")
    )
    }
    }
    

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33. extension Client {
    func fetchItem(id: Int,
    completion: @escaping
    (Result) -> Void)
    {
    …
    let session = URLSession.shared
    session.dataTask(with: urlRequest) {
    …
    }.resume()
    

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34. extension Client {
    func fetchItem(id: Int,
    completion: @escaping
    (Result) -> Void)
    {
    …
    let decoder = JSONDecoder()
    completion(Result {
    try decoder.decode(Item.self,
    from: data)
    })
    }
    }
    

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35. extension Client {
    func fetchUser(id: Int,
    completion: @escaping
    (Result) -> Void)
    {
    let urlRequest = URLRequest(url: baseURL
    .appendingPathComponent(“users")
    .appendingPathComponent("\(id)")
    )
    let session = URLSession.shared
    session.dataTask(with: urlRequest) {
    (data, _, error) in
    if let error = error {
    completion(.failure(error))
    }
    else if let data = data {
    let decoder = JSONDecoder()
    completion(Result {
    try decoder.decode(User.self,
    from: data)
    })
    }
    }.resume()
    }
    }
    

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36. extension Client {
    
    func fetch
    Item(id: Int,
    
    completion:
    
    @escaping (Result<
    Item, Error>) -> Void)
    
    {
    
    let urlRequest = URLRequest(url: baseURL
    
    .appendingPathComponent("
    items")
    
    .appendingPathComponent("\(id)")
    
    )
    
    let session = URLSession.shared
    
    session.dataTask(with: urlRequest) {
    
    (data, _, error) in
    
    if let error = error {
    
    completion(.failure(error))
    
    }
    
    else if let data = data {
    
    let decoder = JSONDecoder()
    
    completion(Result {
    
    try decoder.decode(
    Item.self,
    
    from: data)
    
    })
    
    }
    
    }.resume()
    
    }
    
    }
    extension Client {
    
    func fetch
    User(id: Int,
    
    completion:
    
    @escaping (Result<
    User, Error>) -> Void)
    
    {
    
    let urlRequest = URLRequest(url: baseURL
    
    .appendingPathComponent("
    users")
    
    .appendingPathComponent("\(id)")
    
    )
    
    let session = URLSession.shared
    
    session.dataTask(with: urlRequest) {
    
    (data, _, error) in
    
    if let error = error {
    
    completion(.failure(error))
    
    }
    
    else if let data = data {
    
    let decoder = JSONDecoder()
    
    completion(Result {
    
    try decoder.decode(
    User.self,
    
    from: data)
    
    })
    
    }
    
    }.resume()
    
    }
    
    }
    

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37. extension Client {
    
    func fetch(
    
    _: Model.Type,
    
    id: Int,
    
    completion: @escaping
    
    (Result) -> Void) {
    
    …
    
    let decoder = JSONDecoder()
    
    completion(Result {
    
    try decoder.decode(Model.self,
    
    from: data)
    
    }
    
    }
    

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38. extension Client {
    
    func fetch(
    
    _: Model.Type,
    
    }
    
    }
    
    Client().fetch(id: 1) { … }
    
    Client().fetch(id: 1) {
    
    (result: Result) … }
    

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39. Client().fetch(id: 1) {
    (result: Result) …
    }
    

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40. Client().fetch(User.self, id: 1) { … }
    

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41. extension Client {
    func fetch(
    …) {
    let urlRequest = URLRequest(url: baseURL
    .appendingPathComponent(“???”)
    .appendingPathComponent(“\(id)")
    )
    }
    }
    

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42. protocol Fetchable: Decodable {
    static var apiBase: String { get }
    }
    

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43. extension User: Fetchable {
    
    static var apiBase: String { return "users" }
    }
    
    extension Item: Fetchable {
    
    static var apiBase: String { return “items" }
    }
    
    

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44. let urlRequest = URLRequest(url: baseURL
    
    .appendingPathComponent(Model.apiBase)
    

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45. extension User: Fetchable {
    
    static var apiBase: String { return "users" }
    
    }
    
    extension Item: Fetchable {
    
    static var apiBase: String { return “items" }
    
    }
    
    

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46. Retroactive
    Modeling
    ݩͷιʔεʹΞΫηε͢
    Δ͜ͱ͕Ͱ͖ͳ͍ܕͰ΋
    ػೳΛ֦ு͢Δ͜ͱ͕Ͱ
    ͖Δೳྗ
    The swift programming language swift 5.1
    

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47. ը૾ͷϦϯΫ
    

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48. extension Client {
    
    func fetch(
    
    _: Model.Type, id: Int,
    
    completion: @escaping (Result) -> Void) {
    
    let urlRequest = URLRequest(url: baseURL
    
    .appendingPathComponent(Model.apiBase)
    
    .appendingPathComponent(“\(id)")
    
    )
    
    let session = URLSession.shared
    session.dataTask(with: urlRequest) {
    …
    }.resume()
    }
    
    }
    

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49. protocol URLSessionProtocol {
    
    func dataTask(with request: URLRequest,
    completionHandler: @escaping
    (Data?, URLResponse?, Error?) -> Void)
    -> URLSessionDataTask
    }
    
    extension URLSession: URLSessionProtocol {}
    

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50. struct Client {
    
    let session: URLSessionProtocol
    init(session: URLSessionProtocol) {
    self.session = session
    }
    }
    

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51. MockͷͨΊͷ
    Protocol
    Mock
    ΦϒδΣΫτͷ໛฿
    Protocol
    δΣωϦοΫͳ໰୊ղܾ
    

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52. protocol URLSessionProtocol {
    
    func dataTask(
    
    with request: URLRequest,
    
    completionHandler: @escaping
    
    (Data?, URLResponse?, Error?) -> Void)
    
    -> URLSessionDataTask
    
    }
    

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53. protocol Transport {
    
    func send(request: URLRequest,
    
    completion: @escaping
    
    (Result) -> Void)
    
    }
    URLRequest -> Result
    

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54. struct Client {
    
    let transport: Transport
    init(transport: Transport) {
    self.transport = transport
    }
    }
    
    func fetch(
    
    transport.send(request: urlRequest) {
    
    …
    
    return try decoder.decode(Model.self,
    
    from: result.get())
    

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55. extension URLSession: Transport {
    
    func send(request: URLRequest,
    
    completion: @escaping
    
    (Result) -> Void) {
    
    dataTask(with: request) { (data, _, error) in
    
    if let error = error {
    
    return completion(.failure(error))
    
    }
    
    if let data = data {
    
    completion(.success(data))
    
    }
    
    }.resume()
    
    }
    
    }
    

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56. extension URLSession: Transport {
    
    func send(request: URLRequest,
    
    completion:
    
    @escaping (Result) -> Void) {
    
    }
    
    }
    Retroactive Modeling
    

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57. struct Client {
    init(
    transport: Transport = URLSession.shared
    ) { … }
    }
    let client = Client()
    

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58. sendϝιου͕།Ұͷػೳ
    Foundation಺ͷܕͷΈΛ࢖༻
    URLRequest, Result
    Transport
    

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59. struct TransportWithToken: Transport {
    
    let base: Transport
    
    let token: String
    
    func send(request: URLRequest,
    
    completion: @escaping
    
    (Result) -> Void) {
    
    var newRequest = request
    newRequest.addValue(token,
    forHTTPHeaderField: "token")
    base.fetch(request: newRequest,
    completion: completion)
    }
    
    }
    

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60. final class TestTransport: Transport {
    
    var requests: [Any] = []
    var responseData: [Data]
    init(responseData: [Data]) {
    self.responseData = responseData
    }
    func send(…) {
    
    requests.append(request)
    guard let data
    = responseData.removeFirst() else {
    return completion(.success(data))
    }
    completion(.failure(…))
    
    …
    

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61. protocol Request {
    associatedtype Response: Fetchable
    var baseURL: URL { get }
    var path: String { get }
    var httpMethod: HTTPMethod { get }
    var parameters: [String: Any] { get }
    }
    

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62. protocol Request {
    associatedtype Response: Fetchable
    var baseURL: URL { get }
    var path: String { get }
    var httpMethod: HTTPMethod { get }
    var parameters: [String: Any] { get }
    }
    

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63. protocol Transport {
    func fetch(request: Request)
    }
    ※associatedtype·ͨ͸SelfΛ࢖͏Protocol͸
    δΣωϦΫεͷ੍໿ͱͯ͠࢖༻Ͱ͖Δ͕
    ௚઀ܕͱͯ͠࢖༻Ͱ͖ͳ͘ͳΔ
    PAT(Protocol With AssociatedType)※
    

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64. protocol Transport {
    func fetch(request: R)
    }
    

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65. extension Client {
    
    func multiFetch(requests: [R]) {
    
    for request in requests {
    
    transport.send(request: request)
    
    }
    
    }
    
    }
    
    

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66. ͜ͷProtocol͸
    ഑ྻͱͯ͠࢖͏͔ʁ
    

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67. protocol Request {
    func makeURLRequest()
    throws -> URLRequest
    }
    protocol Transport {
    func send(request: Request,
    completion: @escaping
    (Result) -> Void)
    }
    

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68. struct TransportWithTokenRequest: Request {
    let base: Request
    let token: String
    func makeURLRequest() throws -> URLRequest {
    var newRequest = try base.makeURLRequest()
    newRequest.addValue(token,
    forHTTPHeaderField: "token")
    return newRequest
    }
    }
    

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69. protocol Request {
    func makeURLRequest()
    throws -> URLRequest
    }
    ʁ
    

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70. ՄೳͳݶΓ
    δΣωϦοΫʹ
    
    

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71. ը૾ͷϦϯΫ
    

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72. ը૾ͷϦϯΫ
    

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73. struct Item: Codable {
    
    let id: Int
    
    let name: String
    
    }
    
    struct User: Codable {
    
    let id: Int
    
    let name: String
    
    }
    

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74. let itemId = 1
    client.fetch(User.Type, id: itemId) { … }
    ❌
    

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75. struct Item: Codable {
    
    let id: String
    let name: String
    
    }
    
    func fetch(
    
    _: Model.Type,
    
    id: Int,
    
    …
    ❌
    

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76. protocol Identifiable: Codable, Hashable {
    associatedtype Value
    var value: Value { get }
    init(value: Value)
    }
    extension Identifiable {
    init(_ value: Value) { self.init(value: value) }
    }
    

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77. protocol Identifiable: Codable, Hashable {
    associatedtype Value
    var value: Value { get }
    init(value: Value)
    }
    

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78. let ids: [Identifiable] = [
    User.ID(1),
    Item.ID(“item-1”)
    ]
    PAT(Protocol With AssociatedType)
    

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79. ͜ͷProtocol͸
    ഑ྻͱͯ͠࢖͏͔ʁ
    

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80. protocol Fetchable: Decodable {
    associatedtype ID: Identifiable
    }
    

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81. struct Item: Codable {
    
    struct ID: Identifiable { let value: String }
    let id: ID
    }
    
    struct User: Codable {
    
    struct ID: Identifiable { let value: Int }
    let id: ID
    }
    

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82. func fetch(
    
    _: Model.Type,
    
    id: Model.ID,
    
    …
    

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83. struct Item: Codable {
    
    struct ID: Identifiable { let value: String }
    let id: ID
    
    }
    
    struct User: Codable {
    
    struct ID: Identifiable { let value: Int }
    let id: ID
    
    }
    

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84. func fetch(
    _: Model.Type,
    id: Model.ID,
    …
    

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85. struct Item: Codable {
    struct ID: Identifiable { let value: String }
    let id: ID
    }
    struct User: Codable {
    struct ID: Identifiable { let value: Int }
    let id: ID
    }
    

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86. struct Identifier
    where Value: Codable & Hashable {
    let value: Value
    init(_ value: Value) { self.value = value }
    }
    extension Identifier: Codable, Hashable { … }
    

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87. protocol Fetchable: Decodable {
    
    static var apiBase: String { get }
    
    associatedtype IDType: Codable & Hashable
    typealias ID = Identifier
    var id: ID { get }
    }
    

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88. struct Item: Codable {
    typealias ID = Identifier
    var id: ID { get }
    }
    struct User: Codable {
    typealias ID = Identifier
    var id: ID { get }
    }
    

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89. func fetch(
    _: Model.Type,
    id: Model.ID,
    …
    

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90. protocol Fetchable: Decodable {
    associatedtype IDType: Codable
    typealias ID = Identifier
    var id: ID { get }
    static var apiBase: String { get }
    }
    ࣝผࢠ(Identifier)Λ࣋ͭ
    +
    API͔Βσʔλऔಘ
    

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91. struct Item: Codable {
    typealias = Identifier
    let id: ID
    }
    struct User: Codable {
    typealias = Identifier
    let id: ID
    }
    

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92. protocol Identifiable: Codable {
    associatedtype IDType: Codable & Hashable
    typealias ID = Identifier
    var id: ID { get }
    }
    

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93. protocol Fetchable: Identifiable {
    static var apiBase: String { get }
    }
    

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94. protocol Identifiable: Codable {
    associatedtype IDType: Codable & Hashable
    typealias ID = Identifier
    var id: ID { get }
    }
    protocol Fetchable: Identifiable {
    static var apiBase: String { get }
    }
    ࣝผࢠ(Identifier)Λ࣋ͭ
    IDΛ࢖ͬͯAPI͔Βσʔλऔಘ
    

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95. struct Item: Identifiable {
    typealias IDType = String
    let id: ID
    …
    }
    struct User: Identifiable {
    typealias IDType = Int
    let id: ID
    …
    }
    

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96. POP
    Protocol Oriented
    Programming
    Obsessed
    ※ Obsessed औΓጪ͔ΕΔ
    

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97. Don’t Literally
    Start With a Protocol
    Modern Swift API Design WWDC2019
    Start with a concrete use cases
    Discover a need for generic code
    Try to compose solutions from existing
    protocols first
    Consider a generic type
    instead of a protocol
    

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98. ۩ମతղܾ -> δΣωϦοΫ
    ղܾํ๏Λཧղͯ͠બ୒
    Θ͔Γ΍͍͢ɺ҆શͰ͋Δ
    มߋʹڧ͍
    

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99. ը૾ͷϦϯΫ
    

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100. ΫϦʔϯίʔυΛ
     ॻ͖ଓ͚Δʹ͸ʁ
     

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101. ϘʔΠεΧ΢τͷنଇ
     ίʔυΛܧଓతʹ
     վળ͍ͯ͘͠ϓϩҙࣝ
     ίʔυ͸Կ౓΋ચ࿅͠ͳ͚Ε͹ͳ
     Γ·ͤΜ
     Clean Code ΞδϟΠϧιϑτ΢ΣΞୡਓͷٕ Robert C. Martin(ஶ), ՖҪࢤੜ(༁)
     

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102. Ձ஋ମܥ˞͕ͦ͜໨ඪ
     Ͱ͋Γɺ͜ͷຊͷ
     ςʔϚͩͬͨͷͰ͢ɻ
     Clean Code ΞδϟΠϧιϑτ΢ΣΞୡਓͷٕ Robert C. Martin(ஶ), ՖҪࢤੜ(༁)
     ※ࢥߟɾߦಈ͢Δࡍͷ͋Δಛఆͷ
     ྖҬʹ͓͚ΔՁ஋؍ɾ൑அج४
     

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103. ը૾ͷϦϯΫ
     

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104. View Slide

105. Configurable types
     ~ࣅͯඇͳΔίʔυΛڞ௨ʹѻ͏~
     https://qiita.com/shiz/items/849e483338bd568cb6ab
     ۩ମతͳίʔυ͔Β࢝ΊΑ
     ~ࠓͷ໰୊Λղܾ͠ɺδΣωϦοΫͳίʔυΛݟग़͢~
     https://qiita.com/shiz/items/5755a35887bcb7897464
     มԽʹରԠ͠ຊ࣭Λ࠶ൃݟ͢Δ
     https://qiita.com/shiz/items/7b3bda7c2d84c5a83c0f
     Kickstarter͔ΒֶͿ
     ~ΑΓྑ͍։ൃΛ໨ࢦͨ͢Ίͷ࢓૊Έͱ͸ʁ~
     https://qiita.com/shiz/items/79c7b39f94f32e548df3
     Protocol͸ߏจͷೖΕ෺Ҏ্ͷଘࡏͰ͋Δ
     https://qiita.com/shiz/items/da71d547b59c757cca94
     ิ଍هࣄ
     

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106. ͋Γ͕ͱ͏͍͟͝·ͨ͠
     ը૾ͷϦϯΫ
     

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107. Kickstarter ios-oss
     Star with a protocol
     A mockery of protocols
     That’s not a number
     From Problem to Solution
     Protocol-Oriented Programming in Swift
     Swift Generics (Expanded)
     ࢀߟϦϯΫू
     

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108. Modern Swift API Design
     The swift programming language swift 5.1 Exrtesions
     Protocols are more than Bags of Syntax
     Configurable types in Swift
     ࢀߟϦϯΫू
     

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