On Thu, Aug 19, 2010 at 9:57 PM, Felipe Lessa <felipe.lessa at gmail.com> wrote: > However, I haven't thought about how operations such as 'cons' and > 'tail' would be implemented =). OP just asked about indexing ;-). Well if all you need is indexing, then an integer trie does it, right? http://hackage.haskell.org/package/data-inttrie Luke