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iOS Build a Vending Machine App in Swift Using the Vending Machine Modeling the Vending Machine

Huseyn Guliyev
Huseyn Guliyev
2,603 Points
Posted by Huseyn Guliyev
Huseyn Guliyev
2,603 Points

Error in vend function

Cannot subscript a value of type '[VendingSelection : VendingItem]' with an argument of type '[VendingSelection]'

Here is my code:

class FoodVendingMachine: VendingMachine { 

let selection: [VendingSelection] = [.soda, .dietSoda, .chips, .cookie, .sandwich, .wrap, .candyBar, .popTart, .water, .fruitJuice, .sportsDrink, .gum]

var inventory: [VendingSelection : VendingItem] 

var amountDeposited: Double = 10.0

required init(inventory: [VendingSelection : VendingItem]) {
    self.inventory = inventory
}

func vend( _ quantity: Int, _ slection: VendingSelection) throws {
    guard var item = inventory[selection] else {
        throw VendingMachineError.invalidSelection
    }
}

func deposit(_ amount: Double) {
}

}

1 Answer

Johnny Nguyen
Johnny Nguyen
3,875 Points
Johnny Nguyen
Johnny Nguyen
3,875 Points

Look at your function vend():

Do you name your local argument correctly? It should be "selection" instead of "slection".

Huseyn Guliyev
Huseyn Guliyev
2,603 Points
Huseyn Guliyev
Huseyn Guliyev
2,603 Points

I already found my mistake but thanks anyways!