在斯威夫特，我可以使用for-在枚举初始化或重置一个数组？ [英] In Swift, can I use a for-in enumeration to initialize or reset an array?

问题描述

我现在有一个雨燕类是布尔类型的数组，声明如下：

I currently have an array in a Swift class that is of type Bool, declared as follows:

public var cardIsTaken: [Bool]

有关跟上一个雨燕的风格指南，避免编入索引的循环调用的时候有可能，我有这样的事情的目的：

For purposes of keeping up with a Swift style guide that calls for avoiding indexed for loops when possible, I have something like this:

for takenFlag in cardIsTaken {
    takenFlag = true
}

..这给我的错误消息无法分配到'让'值'takenFlag'。

.. which gives me the error message "cannot assign to 'let' value 'takenFlag'"

出于好奇，我试着用VAR声明它，如：

Out of curiosity, I tried declaring it with "var", as in:

    for var takenFlag in cardIsTaken {
        takenFlag = true
    }

..这只是给了我不同的，不相关的错误消息的整体转换。

.. which just gives me a whole slew of different, unrelated error messages.

我99％肯定它是指在这个时候，我不能用foo的数组，通过数组迭代，如果我想改变的每个值，但如果有一种方法可以做到这一点，我会所有的耳朵。

I am 99% sure it means at this time, I cannot use "for foo in array" to iterate through an array if I want to change each value, but if there IS a way to do it, I'd be all ears.

推荐答案

要做到这一点，最好的办法是使用阵列内置的映射功能。

The best way to do this is to use the array's built in mapping function.

cardIsTaken = cardIsTaken.map { isTaken in true }

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