Swift中带有数组的For-In循环中Iterator元素的可变性 [英] Mutability of the Iterator Element in a For-In loop with an Array in Swift

问题描述

我在Swift 3.0中有一些代码，例如尝试更新元素数组中的属性...

I have some code in Swift 3.0 like so for trying to update the property in a array of elements...

for point in listOfPoints {
    var pointInFrame : Float = Float(point.position.x * sensorIncomingViewPortSize.width) + Float(point.position.y)
    point.status = getUpdateStatus( pointInFrame )
}

但是我得到以下编译错误: 无法分配给属性:'point'是'let'常量" [对于第3行]

However I get a compile error of: 'Cannot assign to property: 'point' is a 'let' constant' [for line 3]

无论如何，有没有在Swift中使迭代器(点)可变的方法，例如如何将'inout'用作函数参数?

Is there anyway to make the iterator (point) mutable in Swift, like how you can use 'inout' for a function parameter?

还是您应该以其他方式执行此任务?

Or are you supposed to do this task another way?

预先感谢.

斯坦

推荐答案

只需将其更改为var，而不是您在其中声明point的let. let是constant.

Just change it to var instead of let where you declare point. let is a constant.

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