来年の素数日を列挙してみた

import Data.Time.Calendar
isPrime n=not $ or $ map (\a->n `mod` a==0)
            $ takeWhile (\i->i*i<=n) [2..]
days=map (\a->filter (/= '-') $ show a) $ takeWhile (< fromGregorian 2013 1 1) 
      $ iterate (\d->addDays 1 d) $ fromGregorian 2012 1 1
main=mapM_ (\a->print a) $ filter (isPrime.read) days