Swift initialize a struct with a closure -

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public struct style {      public var test : int?      public init(_ build:(style) -> void) {        build(self)     } }  var s = style { value in     value.test = 1 }

gives error @ declaration of variable

cannot find initializer type 'style' accepts argument list of type '((_) -> _)'

does know why won't work, seems legit code me

for record won't work either

var s = style({ value in     value.test = 1 })

the closure passed constructor modifies given argument, therefore must take inout-parameter , called &self:

public struct style {      public var test : int?      public init(_ build:(inout style) -> void) {         build(&self)     } }  var s = style { (inout value : style) in     value.test = 1 }  println(s.test) // optional(1)

note using self (as in build(&self)) requires properties have been initialized. works here because optionals implicitly initialized nil. alternatively define property non-optional initial value:

public var test : int = 0

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