No. 240 · August 23, 2026 · Moderate
Filter
Implement `FilterTuple<T, U>` so it keeps only the elements assignable to `U`, preserving order and staying a tuple.
01
Puzzle
Par 3Puzzle
filter-tuple.tsStroke 1 of 3Not run yet
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Checks
4FilterTuple<[1, 'a', 2, 'b'], number>—→ [1, 2]FilterTuple<[], string>—→ []FilterTuple<['x'], number>—→ []FilterTuple<[1, 2, 3], number>—→ [1, 2, 3]
How a check is judged Exact type equality, not assignability — an intersection is not the same as the flattened object.
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Short game
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02
Annotated solution
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