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iOS Build a Vending Machine App in Swift Displaying Additional Views Comparing Answers

Johnny Nguyen
Johnny Nguyen
3,875 Points
Posted by Johnny Nguyen
Johnny Nguyen
3,875 Points

Pasan's mistake

if you put the code:

catch VendingMachineError.invalidSelection

then it doesn't work. You have to put into the else clause

Tagging: Pasan Premaratne

1 Answer

rickkettner
rickkettner
8,061 Points
rickkettner
rickkettner
8,061 Points

This isn't a mistake. Here Pasan is using invalidSelection to guard against a non valid selection being passed in to the Vend function. In other words, it's not being used to guard against "no selection".

However, you are correct in that you may also want to add a similar alert in the else clause for when nothing has been selected. Note: This would NOT be triggered by a catch statement though, so I assume he will be addressing this later.