Mutable Array in Swift

Question

How can I use a Mutable Strongly Type array in Swift? I am adding ShoppingList object to an Array like this:

 func getAllShoppingLists() -> Array<ShoppingList> {

        let shoppingLists = Array<ShoppingList>()

        db.open()

        let results = try! db.executeQuery("SELECT * from ShoppingLists", values: nil)

        defer {

            db.close()
        }

        while(results.next()) {

            let shoppingList = ShoppingList()
            shoppingList.title = results.stringForColumn("title")

            shoppingLists.append(shoppingList)
        }

        return shoppingLists
    }

The problem comes that the shoppingLists is declared as "let". If I change to "var" it works fine. The reason of course is that I am changing the number of items in the array. Is this the best way?

score 2 · Answer 1 · answered Nov 04 '15 at 19:39

2

You can create this code,

var shoppingArray = [ShoppingList]()
shoppingArray.append(yourInstance)

answered Nov 04 '15 at 19:39

Anıl Sözeri

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6

score 1 · Answer 2 · edited May 23 '17 at 12:14

1

That is the only way to make an array mutable, to understand the difference between let and var, see this post, as the answer explains it in detail.

What is the difference between `let` and `var` in swift?

edited May 23 '17 at 12:14

Community

1
1

answered Nov 04 '15 at 18:57

Knight0fDragon

16,609
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score -1 · Answer 3 · answered Jan 16 '22 at 18:22

-1

That's because let represents a constant.

You have to use var if you want to be able to change the shoppingLists content.

answered Jan 16 '22 at 18:22

da Rocha Pires

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You're just repeating what the other answers already say. – Eric Aya Jan 16 '22 at 18:52

Mutable Array in Swift

3 Answers3