2020/4/28 の Swift 愛好会で「_Function Builders」についての話したときに使った資料をアップしました。この機能は発展途上中で、今回は Swift 5.2 の時点での Function Builders を試行錯誤で試したときのお話になります。

23. func serialization() -> String {
var serialized = ""
serialized += String(SerializedValue(turn: turn))
serialized += "n"
serialized += String(SerializedValue(board: board))
serialized += "n"
return serialized
}

24. @Serialization
func serialization() -> String {
turn
board
}

26. @_functionBuilder
enum Sample {
//
}

27. @Sample
func execute() -> Component
{
// DSL
}
init(@Sample body:()->Component) {
// DSL
}

29. 1. buildExpression(_: Expression) -> Component
2. buildBlock(_: Component ...) -> Component
3. buildDo(_: Component ...) -> Component

30. buildEither(first: Component) -> Component
buildEither(second: Component) -> Component

31. buildFunction(_: Components...) -> Return
buildOptional(_: Component?) -> Component

38. static func buildBlock(
_ a: Component, _ b: Component) -> Component {
}

39. static func buildBlock(_ a: Int, _ b: String, _ c: Bool) -> Component {
}

40. static func buildBlock(_ components: Component...) -> Component {
}

41. static func buildBlock(_ a: Int, _: Void) -> Component {
}

42. static func buildExpression() -> Component {
}

45. static func buildExpression(_ expression: Expression) -> Component
{
}

46. static func buildExpression(_: Void) -> Component {
}

47. static func buildExpression(_: Never) -> Component {
}

48. static func buildExpression(_: Never) -> Component {
}
static func buildExpression<T>(_ expression: T) -> T {
return expression
}

49. Do

51. static func buildDo(_ component: Component) -> Component {
}

52. If

54. if … {
①
}
else {
②
}
BLOCK
2nd1st

55. if … {
①
}
else if {
②
}
else {
③
}
2nd1st
BLOCK
2nd1st

56. 2nd1st
if … {
①
}
else if … {
②
}
else if … {
③
}
else {
④
}
BLOCK
2nd1st
2nd1st

57. if … {
①
}
else if … {
②
}
else if … {
③
}
else if … {
④
}
else {
⑤
BLOCK
1st 2nd 1st
2nd
1st 2nd
1st
2nd

58. BLOCK
1st 2nd 1st
2nd
1st 2nd
1st
2nd
1st 2nd

59. BLOCK
1st 2nd 1st
2nd
1st 2nd
1st
2nd
1st 2nd
1st 2nd

60. BLOCK
1st 2nd 1st
2nd
1st 2nd
1st
2nd
1st 2nd
1st 2nd 1st 2nd

61. BLOCK
1st 2n 1st
2nd
1st 2n
1st
2n
1st 2n
1st 2n 1st 2n
1st
2nd

62. BLOCK
1st 2n 1st
2nd
1st 2n
1st
2n
1st 2n
1st 2n 1st 2n
1st
2nd
2nd1st

63. BLOCK
1st 2n 1st
2nd
1st 2n
1st
2n
1st 2n
1st 2n 1st 2n
1st
2nd
2nd1st
1st 2n

64. if … {
①
}
else {
if … {
②
}
else {
③
}
}
BLOCK
2nd1st
2nd1st
BLOCK

67. Build Block
Build ExpressionBuild Expression
Build DoBuild Do
Build Function
Build If
Build Optional
Build Block
Build DoBuild Either
Build Block