Swift initialize array of repeated values with variable IDs

Question

I have some code like this:

var myVariable = Array(repeating: CustomStruct(value: " "), count: 3))

where CustomStruct looks like this:

struct CustomStruct: Hashable {
    var id: UUID = UUID()
    var value: String

    static func == (lhs: CustomStruct, rhs: CustomStruct) -> Bool {
        return lhs.id == rhs.id && lhs.value == rhs.value
    }
}

The initialization of myVariable works fine, but there is a problem because I want the id of every element to be unique, and, because I am essentially making 3 clones of the same item, the ids of every element in the array won't be unique.

As far as I can tell, the only way I can solve this problem is to do brute force it, like this:

[CustomStruct(value: " "), CustomStruct(value: " "), CustomStruct(value: " ")]

but I'd rather not do that, because this example has been minimized and in reality I have ~30 individual elements in the array, so it would be a super long variable declaration.

The reason I want every element to be unique is because I'm using this array with a ForEach loop in SwiftUI, and want to do something like this:

ForEach(myVariable, id: \.id) {_ in
   // do stuff
}

without SwiftUI complaining that there are elements with the same ID in the foreach loop.

I realize one approach could be to initialize through the array in the init() call with some custom logic but I was wondering if there is an alternative/more standard approach here.

Thanks!

Arnaud · Accepted Answer · 2025-05-15 14:23:41Z

2

I prefer this approach

var myVariable = (1...3).map { _ in CustomStruct(value: " ") }

answered May 15 at 14:23

Arnaud

18k9 gold badges69 silver badges90 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

workingdog support Ukraine · Accepted Answer · 2022-07-25 00:48:48Z

1

you could try this approach, works for me:

var myVariable = Array(repeating: (), count: 3).map { CustomStruct(value: " ") }

answered Jul 25, 2022 at 0:48

workingdog support Ukraine

38.9k5 gold badges47 silver badges52 bronze badges

1 Comment

user652038 Over a year ago

There is no reason to use an Array for this. AnyIterator { }.prefix(3)

Collectives™ on Stack Overflow

Swift initialize array of repeated values with variable IDs

2 Answers 2

Comments

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related