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Practice Paths Tracks Cheatsheets Playground Glossary AI era

Practice Paths Tracks Cheatsheets Playground Glossary AI era

Practice / Quiz / JavaScript / JavaScript

What is the value of `[1, 2, 3].map(n => n * 2)`?

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beginner 1 min

What is the value of `[1, 2, 3].map(n => n * 2)`?

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previous kata Name the error class thrown when `[].reduce(callback)` has no initial value Fill in next kata Which expression uses `fallback` only when `count` is `null` or `undefined`, while preser… Quiz

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