This is one with functional lists: diag = foldr1 (zipWith (.) $. id ~> (id:) ~> id) $. map (++ repeat id) ~> takeWhile (not.null.($[])) $. (map.map) (:) ~> ($[]) . mconcat On Apr 20, 2009, at 1:48 PM, Sebastian Fischer wrote:
On Apr 18, 2009, at 2:48 AM, Sjoerd Visscher wrote:
using Matt Hellige's pointless fun http://matt.immute.net/content/pointless-fun
diag = foldr1 (zipWith (++) $. id ~> ([]:) ~> id) $. map (++ repeat []) ~> takeWhile (not.null) $. (map.map) (:[]) ~> concat
pretty! Those seem to be exactly the combinators that I was looking for.
Unfortunately, I still don't manage to mimic my version that uses functional lists and continuations (but no ++) mainly because I'm lacking an equivalent of the second line of the above solution which allows for the simpler 'zipWith (++)' instead of the merge function.
Anyway, once you know what they mean, Matt's combinators are quite useful. Thanks for pointing that out!
Cheers, Sebastian _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
-- Sjoerd Visscher sjoerd@w3future.com