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Data Types · easy

8. Optionals (some, none)

Handling values that may be missing.

1 min read2 questionsup to 50 XPtopic 8/50

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An `optional` is either `(some value)` or `none`. Map lookups and optional trait parameters return optionals.

clarity
(some u10)
none

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Check your understanding

  1. 1. What type does map-get? return?

  2. 2. Which expression checks if an optional contains a value?

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