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iOS Build a Vending Machine App in Swift 2.0 Using the Vending Machine Modeling the Vending Machine

Mahdi Pedramrazi
Mahdi Pedramrazi
2,505 Points
Posted by Mahdi Pedramrazi
Mahdi Pedramrazi
2,505 Points

Item quantity update is misplaced.

shouldn't we decrease the item quantity after we are sure that the user has enough money to purchase ? this line of code can go at the end.

item.quantity -= quantity

3 Answers

Stefan Cimander
Stefan Cimander
37,115 Points
Stefan Cimander
Stefan Cimander
37,115 Points

Yes absolutely, I think so, too. Both lines should be placed after the guard statements at the end of the function:

item.quantity -= quantity
inventory.updateValue(item, forKey: selection)
Drew Carver
Drew Carver
5,189 Points
Drew Carver
Drew Carver
5,189 Points

I agree. I think these two lines:

item.quantity -= quantity
inventory.updateValue(item, forKey: selection)

should go in the if block, right after this statement:

amountDeposited -= totalPrice