enumerator-0.4.3: Examples/skip.hs

module Main where
import Prelude hiding (head)
import Data.Enumerator
import Control.Monad.Trans.Class

skip :: Monad m => Enumeratee a a m b
skip (Continue k) = do
    x <- head
    _ <- head -- the one we're skipping
    case x of
        Nothing -> return $ Continue k
        Just y -> do
            newStep <- lift $ runIteratee $ k $ Chunks [y]
            skip newStep
skip step = return step