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iOS Swift Enums and Structs Enums Review Enums

Posted by huiu7
huiu7
1,508 Points

I don't understand this correct quiz question (regarding data type)

Hello, when doing the quiz, the question is, "What is the data type of the constant today?"

let today = Day(rawValue: 1)

The correct answer is "an Optional". Can somebody please explain to me why this is the correct answer? I'd say it is a Day ...

2 Answers

Pavel Fomchenkov
Pavel Fomchenkov
20,897 Points
Pavel Fomchenkov
Pavel Fomchenkov
20,897 Points

Not all possible Int values will have a matching Day. Because of this, the rawValue initializer always returns an optional enumeration member, an Optional Day.

ayushagarwal2
ayushagarwal2
982 Points

I don't quite follow. What do you mean by an "Optional" day?

huiu7
huiu7
1,508 Points
huiu7
huiu7
1,508 Points

OK, now I think I get it. Thanks a lot, Pavel!