Array not being seen in scope Im not sure why SwiftUI - arrays

Question

Code:
extension Array {
// Total Together An Array
func FindTotal(_ arrayName: [Int]) -> Int {
var currentValue: Int = 0
for i in 0...Int(arrayName.count - 1) {
currentValue = currentValue + Int(arrayName[i])
}
return currentValue
}
// Number Grabber for Calculating the values
func calcItemsD(_ TargetArray: [String]) {
var placeholder: String? = nil
for i in 0...Int(TargetArray.count - 1) {
placeholder = String((TargetArray[i]).character(at: 0)!)
if (placeholder == "1") {
dealerNums.append("")
}
}
}
}
class DeckSetup : ObservableObject {
#Published public var deckOCards: [String] = []
#Published public var yourhand: [String] = []
#Published public var dealerHand: [String] = []
#Published public var dealerNums: [Int] = [7, 2]
#Published public var playerNums: [Int] = []
}
The dealerNums.append("") is throwing the error of out of scope and I am not sure why Heres the all the code that should be relevant.

Answer 1

dealerNums is an array encapsulated in your DeckSetup class. You can't access that from an Array extension.
What you can do, is pass in dealerNums into the function, like so:
func calcItemsD(_ targetArray: [String], dealerNums: inout [Int]) {
var placeholder: String? = nil
for i in 0 ..< targetArray.count {
placeholder = String(targetArray[i].first!)
if placeholder == "1" {
dealerNums.append("")
}
}
}
And called like so from inside your DeckSetup class:
calcItemsD(["1", "K", "A"], dealerNums: &dealerNums)
dealerNums is marked inout, since you are mutating it within the function.
I cleaned up the function a tiny bit, but I don't know if you have more to it. For example, these are more things you could change to improve it:
Iterate with for target in targetArray instead of using the index.
placeholder is not needed to be stored outside the loop as it isn't used. You can have a local let placeholder = ... if needed.
Don't force unwrap (!) the first character. Provide a suitable alternative or fallback.