[Haskell-cafe] Iteratee performance

[Thomas Schilling]

As a general style tip, since you're using language extensions anyway

> {-# LANGUAGE RankNTypes, ScopedTypeVariables #-}

you might want to add "BangPatterns", so you can put the strictness
annotation directly on the argument.  Either by doing this:

   go !n = ...

or later on:

  let !n' = ...
  return I.Cont ...


> cnt = go 0
>  where
>   go n = I.IterateeG $ \ch ->
>       case ch of
>         (I.EOF Nothing)        -> return $ I.Done n ch
>         (I.EOF (Just e))       -> return $ I.Cont cnt (Just e)
>         (I.Chunk (I.WrapBS s)) -> do
>             let n' = n + S.count '\n' s
>             return $ n' `seq` I.Cont (go n') Nothing
>