不推荐使用++，它将在swift 3中删除 [英] ++ is deprecated it will be removed in swift 3

问题描述

++将在swift 3中弃用

++ will be deprecated in swift 3

变量++
现在可写为

variable++ can now be written as

variable += 1

如何重写 ++变量。

请回忆一下 ++变量和变量++ 之间的区别语法

Please recall difference between ++variable and variable++ syntax

推荐答案

将其重写为：

variable += 1

...正如警告信息所示。现在这需要是一个单独的行（当然这是改变的唯一坏处）。重要的是 你把那条线放在哪里。

...exactly as the warning message suggests. This will now need to be a separate line, of course (that's the only bad thing about this change). What matters is where you put that line.

所以例如

let otherVariable = ++variable // variable is a previously defined var

现在变为

variable += 1 // variable is _still_ a previously defined var
let otherVariable = variable

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但是另一方面

---

But on the other hand

let otherVariable = variable++ // variable is a previously defined var

现在变为

let otherVariable = variable
variable += 1 // variable is _still_ a previously defined var

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专家额外费用：在极少数情况下，你返回变量++ - 也就是说，你返回变量，它在更高的范围内，然后递增它 - 你可以像这样解决问题：

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Extra for experts: In the rare situation where you return variable++ — that is, you return variable, which is in a higher scope, and then increment it — you can solve the problem like this:

defer {
    variable += 1
}
return variable

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