Merge Swift Array with same superclass

Question

I\'m trying to find the best way to merge Swift arrays, that are not of same type, but they have same superclass. I\'ve already read all the tutorials so I know I can use:

Answer 1

In addition to Martin's answer, you could create a protocol that all of the classes conform to and then when creating your array, make it's type that protocol.

Then you can add any of the classes to it without casting.

Answer 2

you can merge almost everything. the only requirement is that all elements of resulting array must conform to the same protocol.

let arr1 = [1,2,3]          // [Int]
let arr2 = [4.0,5.0,6.0]    // [Double]
let arr3 = ["a","b"]        // [String]

import Foundation // NSDate
let arr4 = [NSDate()]       // [NSDate]

// the only common protocol in this case is Any
var arr:[Any] = []

arr1.forEach { arr.append($0) }
arr2.forEach { arr.append($0) }
arr3.forEach { arr.append($0) }
arr4.forEach { arr.append($0) }

print(arr) // [1, 2, 3, 4.0, 5.0, 6.0, "a", "b", 2016-02-15 08:25:03 +0000]

Answer 3

If C inherits from A then you can "upcast" an array of type [C] to an array of type [A]

array += anotherArray as [A]

Alternatively, use (tested with Swift 4)

array.append(contentsOf: anotherArray)