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Ios 为什么闭包的实际主体永远不会执行?_Ios_Swift - Fatal编程技术网

Ios 为什么闭包的实际主体永远不会执行?

Ios 为什么闭包的实际主体永远不会执行?,ios,swift,Ios,Swift,来自苹果的Swift编程语言(Swift 5.2测试版) 摘自:苹果公司《Swift编程语言(Swift 5.2测试版)》,苹果图书 在这些示例中,当调用两次somefunctionthatakesaclosure时,它只打印两次声明函数,我想知道这两个闭包的主体是如何未被调用的?您需要更改为以下内容: func someFunctionThatTakesAClosure(closure: () -> Void) { print("Declaring Function") cl

来自苹果的Swift编程语言(Swift 5.2测试版)

摘自:苹果公司《Swift编程语言(Swift 5.2测试版)》,苹果图书


在这些示例中,当调用两次
somefunctionthatakesaclosure
时,它只打印两次声明函数,我想知道这两个闭包的主体是如何未被调用的?

您需要更改为以下内容:

func someFunctionThatTakesAClosure(closure: () -> Void) {
   print("Declaring Function")
   closure()
}

您需要更改为以下内容:

func someFunctionThatTakesAClosure(closure: () -> Void) {
   print("Declaring Function")
   closure()
}