Add Array Multiple Objects to [Any] in Swift 3

Question

I'm trying to understand the best way to add multiple objects of different types to an [Any] array. This doesn't work in a playground in Swift 3, unless I explicitly cast the arrays and the objects in the arrays to Any.

var anyArray: [Any] = []
let strings = ["sup", "cool"]
let numbers = [5, 3]
anyArray += strings
anyArray += numbers
anyArray

It fails with the message - Cannot convert value of type '[Any]' to expected argument type 'inout _'

the inout error has to do with pointers and reference types in swift... can you post the entire method that you are trying to do this in? — MSU_Bulldog, Feb 20 '17 at 15:52
@MSU_Bulldog this is the entirety of the code - it's in a playground. — Alex, Feb 20 '17 at 15:54
@Alex You need to explicitly specify the type of array to `AnyObject`. `anyArray += strings as [AnyObject]` — Nirav D, Feb 20 '17 at 16:00
The answer in the post that this was marked as a duplicate of was what I was looking for and is the correct answer to my question - thank you. — Alex, Feb 20 '17 at 16:03

Gaston Gonzalez · Answer 1 · 2017-02-20T16:04:43.303

1

    var arr = [Any]()
    let arr1:[Any] = [2,3,4]
    let arr2:[Any] = ["32","31"]
    arr += arr1
    arr += arr2
    print(arr)

edited Feb 20 '17 at 16:04

answered Feb 20 '17 at 15:55

Gaston Gonzalez

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3
6

So the error comes from trying to add `[Any]` and `[String]`? – BallpointBen Feb 20 '17 at 15:57
This is really bizzare - I've tried this and the autocomplete suggests `contentsOf:` to me, but then the compiler says 'extraneous argument label contentsOf:' - as an error so I can't even compile with this. I'm on Xcode 8.2.1 – Alex Feb 20 '17 at 15:57
make sure you're explicitly casting the arrays to [Any] or else the compiler will throw the "extraneous argument label" piece – Gaston Gonzalez Feb 20 '17 at 16:01
Once you declare the types of `arr1` and `arr2` as `[Any]`, you can do `arr += arr1` (or `anyArray += strings` in OP's example). No need for `append(contentsOf:)` – BallpointBen Feb 20 '17 at 16:03
made edits to match += syntax – Gaston Gonzalez Feb 20 '17 at 16:05

score 0 · Answer 2 · answered Feb 20 '17 at 15:54

0

I think this is another case of useless error messages from Swift's compiler. The real issue is that AnyObject means any object (reference type); structs -- which both Int and String are -- don't count because they are value types. If you want to refer to any type at all, use Any.

answered Feb 20 '17 at 15:54

BallpointBen

9,406
1
32
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Ah, fair enough, but this doesn't solve the problem, the error message simply changes to be [Any] instead of [AnyObject] – Alex Feb 20 '17 at 15:55

Add Array Multiple Objects to [Any] in Swift 3

2 Answers2