Swift使用var而不是let元素进行循环？

Question

Is there some kind of for in loop like the following?

for var score in scores {
...
}

I want that score is variable. How can I do that?

Edit: I want that score is a var instead of a let. So that I can do:

score = nil

Answer 1

If you want to assign a variable nil the array must be defined with an optional type. Perhaps you can use the Array higher order sequence map to construct a new array?

var scores: [Int?] = [1, 2, 3, 4, nil, 5, 6, 7, 8]
scores = scores.map { (score: Int?) -> Int? in
    return nil
}