You're getting ahead of me again. Michael --- On Sun, 4/12/09, Jake McArthur wrote: From: Jake McArthur Subject: Re: [Haskell-cafe] Functions that return functions To: "michael rice" Cc: haskell-cafe@haskell.org Date: Sunday, April 12, 2009, 5:45 PM michael rice wrote:

Admittedly, functions that return functions are Lispy, but perhaps there a Haskelly way to accomplish the same thing?

Actually, I think you will come to find that this way of thinking is more Haskelly than it is Lispy!     import Control.Applicative ((<$), (<*>))     import Control.Arrow       ((&&&))     import Control.Monad       (guard)     import Data.List           (unfoldr)     makeVerifier f m = (==0) . (`mod` m) . sum . zipWith f [1..] . unfoldr nextDigit         where nextDigit = (<$) . (snd &&& fst) . (`divMod` 10) <*> guard . (/= 0) - Jake