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Test: Swift - Introduction to Optionals 3. var score: Int? - which of the following values can score contain?
Results Congratulations! Correct Answer. You Answered: None. If you took the test, your answer will show up here. Correct Answer: 0; nil; 100; Explanation Type of the variable score is Optional, which means, it can hold either a nil value or an Integer value. 0 and 100 are integers, so, they are ok. But 3.4 is either a Float or a Double. It is not an Int. If you assign score = 3.4, Swift will give an error, since there is no automatic conversion between types in Swift.Take the Test Take the complete test on this topic. You will be able to review answers to questions and get a test score.
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This article talks about the purpose of Optionals in Swift and how to declare them in your code.
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This is a test on basic concepts of Optionals in Swift.
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