快速将[Int]转换为（Int），反之亦然

Question

---

How can I convert an int array

let beforeSorting = [1, 2, 3, 4, 0, 6, 7, 8, 9, 10]

to

(1, 2, 3, 4, 0, 6, 7, 8, 9, 10)

Also in reverse in swift?

Scenario

var a: Int = 0
var b: Int = 0
var c: Int = 0

..likewise 20 variables

I wanted to apply some operations to these values, so I converted the values into array like

let array = [a, b, c,..] // counting 20 elements

After applying some operations like sorting. I need to put these values back to the properties.

So I made an tuple with these properties. Here is my problem. how can I assign my new array to tuple. (Setting all properties at once)

just like (a, b, c, d..) = myarray

Answer 1

Tuples must have a predefined size and type. So all you can do is have some convenience which may be done on many ways. You could for instance create a wrapper:

typealias MyTuple = (a: Int, b: Int, c: Int, d: Int, e: Int, f: Int)
class ToupleWrapper {
    private var values: [Int]
    init(a: Int, b: Int, c: Int, d: Int, e: Int, f: Int) {
        values = [a, b, c, d, e, f]
    }
    convenience init(array: [Int]) {
        self.init(a: array[0], b: array[1], c: array[2], d: array[3], e: array[4], f: array[5])
    }
    convenience init(tuple: MyTuple) {
        self.init(a: tuple.a, b: tuple.b, c: tuple.c, d: tuple.d, e: tuple.e, f: tuple.f)
    }
    var array: [Int] {
        return values
    }
    var tuple: MyTuple {
        return (values[0], values[1], values[2], values[3], values[4], values[5])
    }
}

And usage:

func foo() {
    let arrayFromValue = ToupleWrapper(a: 3, b: 2, c: 1, d: 4, e: 2, f: 2).array
    let arrayFromTouple = ToupleWrapper(tuple: (0, 1, 3, 2, 4, 2)).array
    let tupleFromArray = ToupleWrapper(array: [2, 3, 1, 4, 2, 2]).tuple
}

Answer 2

No, you cannot do this in a safe manner. A tuple has a fixed length that is known at compile time, while the length on an array is something obtained at runtime.

Converting a tuple into an array is possible, but only if all tuple elements are of the same type or have a common type - you can simply reference the .0 ... .10 elements of it.