Chain Selection Before Ordering
Chain Selection Before Ordering
A chain can express a small reporting pipeline: choose the records that matter, order that subset, and transform it into the final shape. The source array should remain stable unless the task specifically asks for mutation.
sort is the risky step because it mutates the array it runs on. Filtering first creates a new array, but later readers should still be able to trust the original member order. A copied sort keeps the pipeline result separate from source state.
Your task: Complete recentActiveEmails so it returns the emails of active members ordered by lastSeen from newest to oldest. Do not mutate the original member array.
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Chain Selection Before Ordering
A chain can express a small reporting pipeline: choose the records that matter, order that subset, and transform it into the final shape. The source array should remain stable unless the task specifically asks for mutation.
sort is the risky step because it mutates the array it runs on. Filtering first creates a new array, but later readers should still be able to trust the original member order. A copied sort keeps the pipeline result separate from source state.
Your task: Complete recentActiveEmails so it returns the emails of active members ordered by lastSeen from newest to oldest. Do not mutate the original member array.