SwiftSyntax で便利を実現する基礎 / How to Use SwiftSyntax for Better Productivity (Japanese version)

SwiftSyntax を使うと、Swift のコード生成や書き換え、静的検査などを実現できます。しかし、SwiftSyntax の使い方はほとんど知られていません。この方法をダイジェストで紹介します。

try! Swift Tokyo 2019
https://www.tryswift.co/events/2019/tokyo/jp/

Transcript

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 ศརΛ࣮ݱ͢Δجૅ Kuniwak - DeNA Co.,Ltd. 2019.03.22 try! Swift Tokyo 2019
2. 2 Some code will be presented in the slides,
 you can see the slides and the code here: ൃදதʹίʔυ͕ग़͖ͯ·͕͢ɺಡΈͮΒ͍৔߹͸
 ҎԼ͔ΒεϥΠυΛ͝ཡ͍ͩ͘͞ɿ speakerdeck.com/orgachem
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   github.com/apple/swift-syntax 8
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10. ಡΈॻ͖͠΍͍͢σʔλ ίʔυΛɺಡΈॻ͖͠΍͍͢σʔλʹ͢Δ ಡΈॻ͖͠΍͍͢σʔλΛɺίʔυʹ͢Δ   4XJGU
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    ಡΈॻ͖͠΍͍͢σʔλ 4XJGU
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    10
11. ಡΈॻ͖͠΍͍͢σʔλ ίʔυΛɺಡΈॻ͖͠΍͍͢σʔλʹ͢Δ ಡΈॻ͖͠΍͍͢σʔλΛɺίʔυʹ͢Δ   4XJGU
    ͷίʔυ
    ಡΈॻ͖͠΍͍͢σʔλ 4XJGU
    ͷίʔυ
    11
12. ίʔυΛɺಡΈॻ͖͠΍͍͢σʔλʹ͢Δ  if let self = self {} 12 આ໌ʹ࢖͏αϯϓϧίʔυ
13. ίʔυΛɺಡΈॻ͖͠΍͍͢σʔλʹ͢Δ  if let self = self {} JGจ 13 ͜Ε͸ʮJGจʯͱݺ͹ΕΔ
14. ίʔυΛɺಡΈॻ͖͠΍͍͢σʔλʹ͢Δ  if let self = self {} if let self = self {} JGจ ෳจ ৚݅ 14 JGจ͸ʮ৚݅ʯͱʮෳจʯͰ
 ߏ੒͞Ε͍ͯΔ
15. ίʔυΛɺಡΈॻ͖͠΍͍͢σʔλʹ͢Δ  if let self = self {} if let self = self {} JGจ ෳจ 0QUJPO
    ଋറ৚݅ 15 ࠓճͷ৚݅෦෼ʹ͸ɺ
 ʮ0QUJPOଋറ৚݅ʯͱ
 ݺ͹Ε͍ͯΔ΋ͷ͕ೖΔ
16. ίʔυΛɺಡΈॻ͖͠΍͍͢σʔλʹ͢Δ  if let self = self {} if let self = self {} JGจ ෳจ 0QUJPO
    ଋറ৚݅ ม਺ࣜ ม਺ύλʔϯ if let self = self {} 16 0QUJPOଋറ৚݅͸ɺ୅ೖઌͷ
 ʮม਺ύλʔϯʯͱ୅ೖ͢Δ஋ͷ
 ʮม਺ࣜʯͰߏ੒͞Ε͍ͯΔ
17. ίʔυΛɺಡΈॻ͖͠΍͍͢σʔλʹ͢Δ  if let self = self {} if let self = self {} if let self = self {} 17 ͜ͷΑ͏ʹɺίʔυΛ෼ղͯ͠
 ߏ੒ཁૉΛḷ͍ͬͯ͘ͱɺ
 ίʔυΛʮ໦ߏ଄ʯͱͯ͠
 ѻ͍ͬͯΔ͜ͱʹؾͮ͘
18. ίʔυΛɺಡΈॻ͖͠΍͍͢σʔλʹ͢Δ  if let self = self {} if let self = self {} if let self = self {} 18 ෳจ JGจ ෳจ ม਺ύλʔϯ ม਺ࣜ 0QUJPO
    ଋറ৚݅
19. ίʔυΛɺಡΈॻ͖͠΍͍͢σʔλʹ͢Δ  if let self = self {} if let self = self {} JGจ ෳจ 0QUJPO
    ଋറ ม਺ࣜ ม਺ύλʔϯ if let self = self {} JGจ ෳจ ม਺ύλʔϯ ม਺ࣜ ͜ΕΛʮߏจ໦ʯͱΑͿ 19 0QUJPO
    ଋറ৚݅
20. 4XJGU4ZOUBY
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21. 4XJGU4ZUOBY
    Ͱߏจ໦ΛಡΉ  if let self = self {} if let self = self {} JGจ ෳจ 0QUJPO
    ଋറ ม਺ࣜ ม਺ύλʔϯ if let self = self {} ม਺໊ΛಡΜͰΈΑ͏ 21
22. import SwiftSyntax let url = URL(fileURLWithPath: "example.swift") let source = try String(contentsOf: url) let syntax = try SyntaxParser.parse(source: source) 4XJGU4ZOUBY
    Ͱ ಡΈॻ͖͠΍͍͢σʔλʢߏจ໦ʣʹ͢Δ 4XJGU
    ͷίʔυΛ 22
23. if let self = self {} if let self = self {} JGจ ෳจ 0QUJPO
    ଋറ ม਺ࣜ ม਺ύλʔϯ if let self = self {} ifStmt 4XJGU4ZUOBY
    Ͱߏจ໦ΛಡΉ  JGจ·ͰͷऔΓํ͸
 গ͠໘౗ͳͷͰޙड़ 23
24. if let self = self {} if let self = self {} JGจ ෳจ 0QUJPO
    ଋറ ม਺ࣜ ม਺ύλʔϯ if let self = self {} ifStmt .conditions[0] .condition 
 4XJGU4ZUOBY
    Ͱߏจ໦ΛಡΉ  24
25. if let self = self {} if let self = self {} JGจ ෳจ 0QUJPO
    ଋറ ม਺ࣜ ม਺ύλʔϯ if let self = self {} "self" ifStmt .conditions[0] .condition .pattern
 .identifier .text 4XJGU4ZUOBY
    Ͱߏจ໦ΛಡΉ  25
26. let name = ifStmt .conditions[0] .condition .pattern
 .identifier .text if name == "this" { print("Oops!") } ྫ͑͹ɺif let self = ͷม਺໊͕
 ౷Ұ͞Ε͍ͯͳ͍৔߹ʹܯࠂͰ͖Δ ߏจ໦ΛಡΊΕ͹ɺΦϨΦϨ
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    ͕ॻ͚Δ  26
27. import SwiftSyntax let url = URL(fileURLWithPath: "example.swift") let source = try String(contentsOf: url) let syntax = try SyntaxParser.parse(source: source)
 let stmts = Array(syntax.statements)
 guard let ifStmt = stmts.first?.item as? IfStmtSyntax else { print("If statement not found at the position.") return } JGจ͸গ͠ख͕ؒͩ͜ͷΑ͏ʹऔΕΔɻ࣮ࡍͷߏจ໦Λ
    EVNQ
    ͢ΔͱΘ͔Δ JGจ·ͰͷऔΓํ 27 ൃ ද Ͱ ͸ ল ུ
28. ಡΈॻ͖͠΍͍͢ߏจ໦ ίʔυΛɺಡΈॻ͖͠΍͍͢ߏจ໦ʹ͢Δ ಡΈॻ͖͠΍͍͢ߏจ໦Λɺίʔυʹ͢Δ   4XJGU
    ͷίʔυ
    ಡΈॻ͖͠΍͍͢σʔλ 4XJGU
    ͷίʔυ
    DONE 28
29. ίʔυΛɺಡΈॻ͖͠΍͍͢σʔλʹ͢Δ ಡΈॻ͖͠΍͍͢ߏจ໦Λɺίʔυʹ͢Δ   4XJGU
    ͷίʔυ
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    ͷίʔυ
    ಡΈॻ͖͠΍͍͢ߏจ໦ ಡΈॻ͖͠΍͍͢ߏจ໦ DONE 29
30. if let this = self {} 4XJGU4ZUOBY
    Ͱमਖ਼ͨ͠ίʔυΛੜ੒͢Δ  if let self = self {} 30
31. import SwiftSyntax class RenameRewriter: SyntaxRewriter { override func visit(_ node: IdentifierPatternSyntax) -> PatternSyntax { if node.identifier.text == "this" { var modifiedNode = node modifiedNode.identifier = SyntaxFactory .makeIdentifier("self") return modifiedNode } return node } } let syntax = try SyntaxParser.parse(source: String(contentsOf: url)) print(RenameRewriter().visit(syntax)) 31
32. import SwiftSyntax class RenameRewriter: SyntaxRewriter { override func visit(_ node: IdentifierPatternSyntax) -> PatternSyntax { if node.identifier.text == "this" { var modifiedNode = node modifiedNode.identifier = SyntaxFactory .makeIdentifier("self") return modifiedNode } return node } } let syntax = try SyntaxParser.parse(source: String(contentsOf: url)) print(RenameRewriter().visit(syntax)) 4XJGU4ZOUBY
    Λ࢖͏ 32
33. import SwiftSyntax class RenameRewriter: SyntaxRewriter { override func visit(_ node: IdentifierPatternSyntax) -> PatternSyntax { if node.identifier.text == "this" { var modifiedNode = node modifiedNode.identifier = SyntaxFactory .makeIdentifier("self") return modifiedNode } return node } } let syntax = try SyntaxParser.parse(source: String(contentsOf: url)) print(RenameRewriter().visit(syntax)) 4XJGU4ZOUBY
    ͰಡΈॻ͖͠΍͍͢ߏจ໦ʹ͢Δ 33
34. import SwiftSyntax class RenameRewriter: SyntaxRewriter { override func visit(_ node: IdentifierPatternSyntax) -> PatternSyntax { if node.identifier.text == "this" { var modifiedNode = node modifiedNode.identifier = SyntaxFactory .makeIdentifier("self") return modifiedNode } return node } } let syntax = try SyntaxParser.parse(source: String(contentsOf: url)) print(RenameRewriter().visit(syntax)) ߏจ໦Λॻ͖׵͑ͯɺ݁ՌΛදࣔ͢Δ 34
35. import SwiftSyntax class RenameRewriter: SyntaxRewriter { override func visit(_ node: IdentifierPatternSyntax) -> PatternSyntax { if node.identifier.text == "this" { var modifiedNode = node modifiedNode.identifier = SyntaxFactory .makeIdentifier("self") return modifiedNode } return node } } let syntax = try SyntaxParser.parse(source: String(contentsOf: url)) print(RenameRewriter().visit(syntax)) ߏจ໦Λॻ͖׵͑ΔͨΊͷΫϥε 35
36. import SwiftSyntax class RenameRewriter: SyntaxRewriter { override func visit(_ node: IdentifierPatternSyntax) -> PatternSyntax { if node.identifier.text == "this" { var modifiedNode = node modifiedNode.identifier = SyntaxFactory .makeIdentifier("self") return modifiedNode } return node } } let syntax = try SyntaxParser.parse(source: String(contentsOf: url)) print(RenameRewriter().visit(syntax)) ॻ͖׵͍͑ͨߏจ໦ͷ
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37. import SwiftSyntax class RenameRewriter: SyntaxRewriter { override func visit(_ node: IdentifierPatternSyntax) -> PatternSyntax { if node.identifier.text == "this" { var modifiedNode = node modifiedNode.identifier = SyntaxFactory .makeIdentifier("self") return modifiedNode } return node } } let syntax = try SyntaxParser.parse(source: String(contentsOf: url)) print(RenameRewriter().visit(syntax)) JG
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    ͳΒॻ͖׵͑Δ 37
38. import SwiftSyntax class RenameRewriter: SyntaxRewriter { override func visit(_ node: IdentifierPatternSyntax) -> PatternSyntax { if node.identifier.text == "this" { var modifiedNode = node modifiedNode.identifier = SyntaxFactory .makeIdentifier("self") return modifiedNode } return node } } let syntax = try SyntaxParser.parse(source: String(contentsOf: url)) print(RenameRewriter().visit(syntax)) 9
    ෦෼Λ
    TFMG
    ʹॻ͖׵͑Δ 38
39. import SwiftSyntax class RenameRewriter: SyntaxRewriter { override func visit(_ node: IdentifierPatternSyntax) -> PatternSyntax { if node.identifier.text == "this" { var modifiedNode = node modifiedNode.identifier = SyntaxFactory .makeIdentifier("self") return modifiedNode } return node } } let syntax = try SyntaxParser.parse(source: String(contentsOf: url)) print(RenameRewriter().visit(syntax)) 39
40. import SwiftSyntax class RenameRewriter: SyntaxRewriter { override func visit(_ node: IdentifierPatternSyntax) -> PatternSyntax { if node.identifier.text == "this" { var modifiedNode = node modifiedNode.identifier = SyntaxFactory .makeIdentifier("self") return modifiedNode } return node } } let syntax = try SyntaxParser.parse(source: String(contentsOf: url)) print(RenameRewriter().visit(syntax)) "if let self= self {}" 40 ίʔυΛੜ੒Ͱ͖ͨʂ
41. import SwiftSyntax class RenameRewriter: SyntaxRewriter { override func visit(_ node: IdentifierPatternSyntax) -> PatternSyntax { if node.identifier.text == "this" { var modifiedNode = node modifiedNode.identifier = SyntaxFactory .makeIdentifier("self") return modifiedNode } return node } } let syntax = try SyntaxParser.parse(source: String(contentsOf: url)) print(RenameRewriter().visit(syntax)) "if let self= self {}" 41 Α͘ݟΔͱۭന͕
 ফ͑ͯ͠·͍ͬͯΔ
42. import SwiftSyntax class RenameRewriter: SyntaxRewriter { override func visit(_ node: IdentifierPatternSyntax) -> PatternSyntax { if node.identifier.text == "this" { var modifiedNode = node let originalIdentifier = node.identifier modifiedNode.identifier = SyntaxFactory .makeIdentifier("self") .withTrailingTrivia(originalIdentifier.trailingTrivia) return modifiedNode } return node } } let syntax = try SyntaxParser.parse(source: String(contentsOf: url)) print(RenameRewriter().visit(syntax)) TFMG
    ޙͷۭന͕ͳ͘ͳΔ໰୊͸
    5SJWJB
    Ͱௐ੔Ͱ͖Δ ൃ ද Ͱ ͸ ল ུ 42
43. if let this = self {} 4XJGU4ZUOBY
    Ͱमਖ਼ͨ͠ίʔυΛੜ੒͢Δ  if let self = self {} 43 DONE
44. ίʔυΛɺಡΈॻ͖͠΍͍͢ߏจ໦ʹ͢Δ ಡΈॻ͖͠΍͍͢ߏจ໦Λɺίʔυʹ͢Δ   4XJGU
    ͷίʔυ
    4XJGU
    ͷίʔυ
    ಡΈॻ͖͠΍͍͢ߏจ໦ ಡΈॻ͖͠΍͍͢ߏจ໦ DONE 44 DONE
45. 4XJGU4ZOUBY
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 4XJGU
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 मਖ਼ͨ͠ίʔυΛ
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    Ͱ͖ͨʂ ·ͱΊ 45