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4 Cards in this Set
- Front
- Back
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What is an optional type? |
An optional is an enum with two cases. One contains a nil, the other a value. |
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How do we show that a type is optional |
Place a ? after the type declaration. |
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How would we declare a variable named 'number' as an optional Int? |
var number:Int? |
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What does the var number:Int contain? |
nil |
