a 如何在结构中使用 setter 的值进行操作？

Question

我有 swift 结构的 getter 和 setter 代码。 newValue 的值是如何进入这个 setter 的？不知道是怎么定义的

struct Program {
var allResults : [String] = []
var items: Int {
    get {
        return allResults.count
    }
    set {            
        let result = String(newValue * 100) // what's that newValue, how did it get there?
        allResults.append(result)    
    }
}

Answer 1

叫做ShorthandSetter宣言.

引用自 Swift 3 本书：

If a computed property’s setter does not define a name for the new value to be set, a default name of newValue is used.

如果你想要更好的可读格式，你可以使用这个：

...
set (newItems) { //add your own variable named as you like
    let result = String(newItems * 100)
    allResults.append(result)
}    
...

a 如何在结构中使用 setter 的值进行操作？

How can a operate with value of setter in structs?

struct

getter-setter

swift