[Haskell] implementing pointers-based data structure

[Jared Updike]

You could check out the data structures in Edison, a library of myriad
functional data structures. It may already have implemented a sequence
data structure with the desired features:
   http://www.eecs.tufts.edu/~rdocki01/docs/edison/index.html
homepage:
  http://www.eecs.tufts.edu/~rdocki01/edison.html

Cheers
  Jared.
--
http://www.updike.org/~jared/
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