[Dn_Ab]

Up top http://news.ycombinator.com/item?id=3444688 I gave working code that comes close. To be fair the reason why it gets closer (works with both F# and C# lists,arrays, sequences,dictionaries,maps,strings etc) is clerical. From this thread, I understand Scala and Java arrays are divorced.

But the problem is: put in a string and it gives back a list of characters. So I use the term it is "topologically correct" heh. To be honest I do not think there is anything functional about what he is attempting but perhaps the idioms in Scala are different? My knowledge of scala is mostly horizontal (from Ocaml,F#, haskell).

[soc88]

Returning the most precise result types (both collection _and_ element type) is a requirement. If this wouldn't be required, the problem would be much easier.