packed-mapMaybe.scp (312B)
1 -- Experiment only: mapper travels alongside the list in the input envelope. 2 consumer packedMapMaybe 3 ([], mapper) @ _ => [] 4 ([x | xs], mapper) @ _ => call mapper x as optional in 5 match optional of ( 6 leaf => recur (xs, mapper) @ leaf 7 | stem value => [value | recur (xs, mapper) @ leaf])