Maybe has a Monad instance, so you can write this as follows (untested):
exists str wmap = boolFromMaybe exists'
where exists' =
do x <- Map.lookup (sort str) wmap
find (== str) (snd x)
boolFromMaybe (Just _) = True
boolFromMaybe Nothing = False
/g
On 2/4/07, Martin DeMello
I have a Data.Map.Map String -> (Layout, [String]) as follows:
type Anagrams = [String] type Cell = (Layout, Anagrams) type WordMap = Map.Map String Cell
exists str wmap = let a = Map.lookup (sort str) wmap in case a of Nothing -> False Just x -> case (find (== str) (snd x)) of Nothing -> False _ -> True
the existence test looks ugly - any more compact way to write it?
martin _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
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